JP6773591B2 - Tap changer - Google Patents

Description

The present invention relates to a tap changer for switching an energizing tap of an adjusting transformer used in an automatic voltage regulator.

Conventionally, in a distribution system, an automatic voltage regulator (SVR: Step Voltage Regulator) for distribution has been installed in order to keep the system voltage within a set range. The automatic voltage regulator automatically adjusts the voltage by, for example, switching the energizing tap of the adjusting transformer according to the voltage on the secondary side (see, for example, Patent Document 1).

In the automatic voltage regulator, the tap changer was used to switch the energizing tap of the adjusting transformer. FIG. 5 is a diagram showing an example of the conventional tap changer 100. The tap changer 100 includes a single-phase reversible motor 123, a switch, a relay, a relay switch operated by the relay, and the like. The single-phase reversible motor 123 has a capacitor 123a and windings 123b and 123c.

The operation of the tap changer 100 will be described with reference to FIG. When the tap changer 100 is automatically controlled, the switch 103 is turned on. When the single-phase reversible motor 123 is rotated in the first direction, the switch 111 is temporarily turned on in response to a command from the CPU or the like. Then, the single-phase AC power supply 101 is supplied to the relay 115 via the b-contact relay switch 113 (88L). When the current flows through the relay 115 in this way, the a-contact relay switches 119 (88R), 121 (88R), and 129 (88R) are closed, and the b-contact relay switch 112 (88R) is opened. As a result, the supply of power to the relay 114 is blocked, and it is possible to prevent the power from being supplied to both terminals of the single-phase reversible motor 123. Further, when the relay switch 121 (88R) is closed, the single-phase reversible motor 123 rotates in the first direction. The switch 127, which is turned on only during the rotation period of one tap of the single-phase reversible motor 123, is closed in response to the rotation of the single-phase reversible motor 123 in the first direction, and a current flows through the relay 130. As a result, the relay switch 120 (22) is closed, and a current flows through the relay 115 via the relay switch 120 (22) and the relay switch 119 (88R), so that the supply of the current to the relay 88R is maintained. Will be done. After that, the switch 111 may be opened. When the rotation of the single-phase reversible motor 123 for one tap is completed, the switch 127 is opened, no current flows through the relay 130, and the relay switch 120 (22) is opened. As a result, no current is supplied to the relay 115, and the relay switch 121 (88R) is opened, so that the rotation of the single-phase reversible motor 123 in the first direction is stopped. When the single-phase reversible motor 123 is rotated in the second direction, the single-phase reversible motor 123 is similarly rotated in the second direction by one tap by temporarily turning on the switch 110. It will be. However, when a current flows through the relay 114, the relay switch whose code includes (88L) operates.

When the tap changer 100 is manually controlled, the switch 103 is opened. Then, when the single-phase reversible motor 123 is rotated in the boosting direction, the boosting switch 105 is manually temporarily turned on. Then, a current is supplied to the relay 115 via the b-contact relay switches 108 (67X) and 113 (88L), and the single-phase reversible motor 123 rotates in the first direction in the same manner as described above. In the case of forward power transmission in the automatic voltage regulator, it is assumed that the rotation in the first direction is the rotation in the boosting direction on the secondary side. Further, when the power transmission direction of the automatic voltage regulator is reverse power transmission, the switch 125 is turned on. Then, a current flows through the relay 126, the relay switches 107 (67X) and 109 (67X) of the a contact are closed, and the relay switches 106 (67X) and 108 (67X) of the b contact are opened. As a result, the rotation direction of the single-phase reversible motor 123 when the step-down switch 104 or the step-up switch 105 is operated is reversed.

Further, when the single-phase reversible motor 123 rotating in the first direction rotates beyond the tap at the end, the rotation is stopped by opening the limit switch 117 of the b contact. On the contrary, when the single-phase reversible motor 123 rotating in the second direction rotates beyond the tap at the end, the rotation is stopped by opening the limit switch 116 of the b contact.

Japanese Unexamined Patent Publication No. 2001-190025

In the tap changer 100 shown in FIG. 5, a mechanical relay is used to control the single-phase reversible motor 123. The mechanical relay has a limited life because the contacts wear each time the switch is opened and closed. Further, in recent years, the frequency of voltage adjustment in an automatic voltage regulator tends to increase in response to reverse power flow from a distributed power source such as photovoltaic power generation. Therefore, there is a problem that the life of the tap changer 100 is shortened. Further, when a mechanical relay is used, there is a problem that it is vulnerable to vibration and shock.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a tap changer having a longer life and being resistant to vibration and shock.

In order to achieve the above object, the tap switching device according to the present invention is a motor for switching the energizing tap of the adjusting transformer used in the automatic voltage regulator, has first and second terminals, and has a single-phase AC power supply. From a single-phase reversible motor, which is a motor that rotates in the first direction when supplied to one terminal and rotates in the second direction when a single-phase AC power supply is supplied to the second terminal, and a single-phase AC power supply. The first rectifier circuit, which is a circuit that rectifies the AC signal and outputs the first instruction signal when the single-phase reversible motor is rotated in the first direction, and the AC signal from the single-phase AC power supply are rectified. A second rectifier circuit, which is a circuit that outputs a second instruction signal when the single-phase reversible motor is rotated in the second direction, and a single-phase AC power supply to the first terminal in response to the first instruction signal. It is a circuit that controls the supply of the single-phase AC power supply to the second terminal in response to the first switching circuit and the second instruction signal, which is a circuit configured by using semiconductor elements. , A second opening / closing circuit, which is a circuit configured by using a semiconductor element, is provided.
With such a configuration, since the first and second switching circuits can be configured by semiconductor elements, the life can be extended as compared with the case where a mechanical relay is used, and the life is also strong against vibration and shock.

Further, in the tap switching device according to the present invention, the first opening / closing circuit includes a first triac arranged between the single-phase AC power supply and the first terminal, a first light emitting element that emits light by a first instruction signal, and a first light emitting element. It is equipped with a first phototriac that supplies an AC signal from the single-phase AC power supply to the gate of the first triac when receiving light from the first light emitting element, and the second switching circuit is a single-phase AC power supply and a first. When the second triac arranged between the two terminals, the second light emitting element that emits light by the second instruction signal, and the light from the second light emitting element are received, the AC signal from the single-phase AC power supply is the second. A second photo triac supplied to the gate of the two triacs may be provided.
With such a configuration, it is possible to realize the first and second switching circuits capable of controlling the high current alternating current used for driving the single-phase reversible motor.

Further, in the tap switching device according to the present invention, the first and second rectifier circuits have the first and second constant current diodes, respectively, and the first instruction signal is the first rectifier circuit via the first constant current diode. The second indicator signal may be output from the second rectifier circuit via the second constant current diode.
With such a configuration, the first and second instruction signals output from the first and second rectifier circuits can be made to have a predetermined current. As a result, the light emission of the light emitting element can be stabilized in the semiconductor relay or the like to which the first and second instruction signals are input, and the semiconductor relay or the like can be operated appropriately.

Further, in the tap switching device according to the present invention, when the single-phase reversible motor is rotated in the first direction by automatic control, a semiconductor relay that temporarily supplies the AC signal of the single-phase AC power supply to the first rectifying circuit and an automatic one. When the single-phase reversible motor is rotated in the second direction by control, a semiconductor relay that temporarily supplies the AC signal of the single-phase AC power supply to the second rectifier circuit and a single-phase reversible motor connected to the single-phase AC power supply. A switch that is turned on at the time of rotation, a semiconductor relay that supplies an AC signal from a single-phase AC power supply connected to the switch and supplied via the switch to the first rectifying circuit according to the first instruction signal, and a switch. A semiconductor relay that supplies an AC signal from a single-phase AC power supply connected to and supplied via a switch to a second rectifying circuit in response to a second instruction signal, and a varistor arranged in parallel with each semiconductor relay. And may be further provided.
With such a configuration, even when an overvoltage occurs, the possibility that the semiconductor relay is destroyed by the varistor arranged in parallel with the semiconductor relay can be reduced.

Further, in the tap switching device according to the present invention, in the case of forward transmission in the automatic voltage regulator, the rotations of the single-phase reversible motor in the first and second directions are the rotations of the step-up side and the step-down side, respectively, and are manually controlled. When rotating the single-phase reversible motor to the step-up side, a boost switch that temporarily supplies the AC signal of the single-phase AC power supply, and when rotating the single-phase reversible motor to the step-down side by manual control, single-phase AC A b-contact semiconductor relay that is placed between the step-down switch that temporarily supplies the AC signal of the power supply and the step-up switch and the first rectifying circuit, and operates in response to the first reverse power transmission signal input during reverse power transmission. Is placed between the step-down switch and the second rectifying circuit and operates in response to the first reverse transmission signal, and is placed between the step-up switch and the second rectifying circuit during reverse power transmission. An a-contact semiconductor relay that operates in response to the second reverse transmission signal input to, and an a-contact semiconductor relay that is arranged between the step-down switch and the first rectifying circuit and operates in response to the second reverse transmission signal. The automatic voltage regulator further includes a signal output unit that outputs the first and second reverse transmission signals when the transmission direction is reverse transmission, and the signal output unit includes an a-contact semiconductor relay and a b-contact semiconductor relay. The first and second reverse transmission signals may be output so that there is no period in which both are closed at the same time.
With such a configuration, the operation timings of the a-contact semiconductor relay and the b-contact semiconductor relay may differ, but it is possible to prevent both semiconductor relays from being closed at the same time, and as a result, the single-phase reversible motor. Can be prevented from breaking down. Further, with the above configuration, for example, even if the AC / DC converter that converts the AC power from the single-phase AC power source into DC power fails, the tap switching device can be operated manually. Become.

Further, in the tap switching device according to the present invention, the signal output unit outputs the first reverse power transmission signal first when the forward power transmission is changed to the reverse power transmission, and then outputs the second reverse power transmission signal, from the reverse power transmission. The output of the second reverse power transmission signal may be stopped first when the forward power transmission is performed, and then the output of the first reverse power transmission signal may be stopped.
With such a configuration, it is possible to prevent the a-contact semiconductor relay and the b-contact semiconductor relay from being closed at the same time regardless of which of the a-contact semiconductor relay and the b-contact semiconductor relay operates earlier. Can be done.

According to the tap changer according to the present invention, by forming at least a part of the structure with a semiconductor element, the life can be extended as compared with the case where a mechanical relay is used, and the life is made stronger against vibration and shock.

A circuit diagram showing a circuit configuration of a tap changer according to an embodiment of the present invention. A circuit diagram showing a circuit configuration of a third switching circuit according to the same embodiment. A circuit diagram showing a circuit configuration of a fourth switching circuit according to the same embodiment. The figure which shows an example of the 1st and 2nd reverse power transmission signals, etc. in the same embodiment Circuit diagram showing the configuration of a conventional tap changer

Hereinafter, the tap changer according to the present invention will be described with reference to embodiments. In the following embodiments, the components with the same reference numerals are the same or correspond to each other, and the description thereof may be omitted again. In the tap changer according to the present embodiment, the motor for switching the energizing tap is controlled by using a semiconductor element without using a mechanical relay.

FIG. 1 is a circuit diagram showing a circuit configuration of the tap changer 1 according to the present embodiment. The tap switching device 1 according to the present embodiment switches the energizing tap of the adjusting transformer (not shown) used in the automatic voltage regulator (SVR) for power distribution, and is the single-phase reversible motor 11 and the first. The switching circuit 12, the second switching circuit 13, the first rectifying circuit 14, the second rectifying circuit 15, the switches 16, 17, 19, the third switching circuit 18, the step-up switch 20, and the step-down switch 21. The fourth open / close circuit 22, semiconductor relays 31 to 34, and limit switches 35 and 36 are provided. The tap changer 1 may, for example, switch the SVR energizing tap used in the three-phase distribution line. The single-phase AC power supply 10 may be, for example, one in which the AC voltage of a certain phase (for example, about 6600V) of the three-phase distribution lines is stepped down to about 110V.

The single-phase reversible motor 11 is a motor for switching the energizing tap of the adjusting transformer of the SVR, and is a capacitor motor having a capacitor 11a and windings 11b and 11c. Further, the single-phase reversible motor 11 has a first terminal 11d and a second terminal 11e, and when the single-phase AC power supply 10 is supplied to the first terminal 11d, that is, the single-phase AC power supply 10 is connected to the winding 11b. When the AC power from the above is supplied and the AC power whose phase is changed by the capacitor 11a is supplied to the winding 11c, it rotates in the first direction and the single-phase AC power supply 10 is supplied to the second terminal 11e. That is, the motor rotates in the second direction when the AC power from the single-phase AC power source 10 is supplied to the winding 11c and the AC power whose phase is changed by the capacitor 11a is supplied to the winding 11b. For example, the rotation of the single-phase reversible motor 11 in the first direction may be considered to be forward rotation, and the rotation in the second direction may be considered to be reverse rotation, or vice versa. Further, when the single-phase reversible motor 11 rotates in the first direction, whether the voltage to be controlled is stepped up or stepped down in the SVR depends on the power transmission direction, but in the present embodiment, in the SVR. In the case of forward power transmission, the rotation of the single-phase reversible motor 11 in the first direction is the rotation of the step-up side on the secondary side, and the rotation in the second direction is the rotation of the step-down side on the secondary side. Therefore, in the present embodiment, in the case of reverse power transmission in SVR, the rotation of the single-phase reversible motor 11 in the second direction is the rotation of the boost side on the primary side, and the rotation in the first direction is the rotation of the step-down side on the primary side. It becomes the rotation of. The single-phase reversible motor 11 may have a configuration other than that shown in FIG. 1 as long as it operates in the same manner according to the supply of the single-phase AC power supply.

The first switching circuit 12 is a circuit that controls the supply of the single-phase AC power supply 10 to the first terminal 11d in response to a first instruction signal described later, and is a circuit configured by using a semiconductor element. The first switching circuit 12 includes a first triac 12a, a first light emitting element 12b, a first photo triac 12c, and a first current limiting resistor 12d.

The first triac 12a is a triac arranged between the single-phase AC power supply 10 and the first terminal 11d. The first triac 12a may be provided with, for example, a snubber circuit having a resistor and a capacitor as a protection circuit for high voltage absorption. The first light emitting element 12b emits light by the first instruction signal output from the first rectifier circuit 14. The first light emitting element 12b may be, for example, an LED (Light Emitting Diode). The first photo triac 12c is a photo triac arranged between the single-phase AC power supply 10 and the gate of the first triac 12a, and is a single-phase AC power supply 10 when receiving light from the first light emitting element 12b. The AC signal from is supplied to the gate of the first triac 12a. It is preferable that the wiring length from the first photo triac 12c to the gate of the first triac 12a is short. The wiring length may be, for example, 15 cm or less. The first current limiting resistor 12d is a resistor for limiting the current input to the first phototriac 12c. When the first instruction signal is input in the first switching circuit 12, the first light emitting element 12b emits light, an AC signal flows through the first phototriac 12c, and the AC signal is supplied to the gate of the first triac 12a. As a result, the first triac 12a is turned on and the single-phase AC power supply 10 is supplied to the first terminal 11d of the single-phase reversible motor 11. On the other hand, when the first instruction signal is no longer input, the first light emitting element 12b stops emitting light, and the supply of the AC signal from the first photo triac 12c to the gate of the first triac 12a is stopped, so that the first triac 12a When it is turned off, the single-phase AC power supply 10 is not supplied to the first terminal 11d. By using a triac as a switch for controlling the supply of the single-phase AC power supply 10, it is possible to control a large current as compared with a semiconductor relay such as a photoMOS relay. Since the first current limiting resistor 12d is provided to protect the first phototriac 12c from the surge current, for example, when the first phototriac 12c can be protected from the surge current by another method or the like. The first switching circuit 12 does not have to have the first current limiting resistor 12d. Further, the first switching circuit 12 provides varistor (not shown) arranged in parallel with the first triac 12a and the first photo triac 12c in order to protect the first triac 12a and the first photo triac 12c from overvoltage. You may have.

The second switching circuit 13 is a circuit that controls the supply of the single-phase AC power supply 10 to the second terminal 11e in response to a second instruction signal described later, and is a circuit configured by using a semiconductor element. The second switching circuit 13 includes a second triac 13a, a second light emitting element 13b, a second photo triac 13c, and a second current limiting resistor 13d.

The second triac 13a is a triac arranged between the single-phase AC power supply 10 and the second terminal 11e. The second light emitting element 13b emits light by the second instruction signal output from the second rectifier circuit 15. The second phototriac 13c is a phototriac arranged between the single-phase AC power supply 10 and the gate of the second triac 13a, and is a single-phase AC power supply 10 when receiving light from the second light emitting element 13b. The AC signal from is supplied to the gate of the second triac 13a. The second current limiting resistor 13d is a resistor for limiting the current input to the second phototriac 13c. The second instruction signal, the second triac 13a, the second light emitting element 13b, the second photo triac 13c, and the second current limiting resistor 13d are the first instruction signal, the first triac 12a, the first light emitting element 12b, and the second, respectively. It corresponds to 1 photo triac 12c and 1st current limiting resistor 12d, and detailed description thereof will be omitted.

The first rectifier circuit 14 is a circuit that rectifies an AC signal from the single-phase AC power supply 10. Further, the first rectifier circuit 14 outputs a first instruction signal when the single-phase reversible motor 11 is rotated in the first direction. As shown in FIG. 1, the first rectifier circuit 14 includes a diode bridge 14a, a step-down resistor 14b, a constant voltage diode 14c, a capacitor 14d, and a first constant current diode 14e.

The AC signal input to the first rectifier circuit 14 is full-wave rectified by the diode bridge 14a composed of four diodes. The voltage after rectification is divided by the step-down resistor 14b and the constant voltage diode 14c. By using the constant voltage diode 14c for the partial pressure, heat generation at the time of partial pressure can be suppressed. The capacitor 14d arranged in parallel with the constant voltage diode 14c is a smoothing capacitor. The anode side of the first constant current diode 14e is connected to the anode side of the constant voltage diode 14c, and the first instruction signal is output from the first rectifier circuit 14 via the first constant current diode 14e. By outputting the first indicator signal via the first constant current diode 14e, the current of the first indicator signal can be set to a predetermined value. As a result, the light emission of the light emitting element according to the first instruction signal can be stabilized, and the operation of the semiconductor relay or the like that operates in response to the light emission can also be stabilized. That is, it is possible to avoid a situation in which the light emitting element does not emit light even if the first instruction signal is output. The method of connecting the light emitting elements that emit light by the first instruction signal is not limited, but it is preferable that the light emitting elements are connected in series. For example, in FIG. 1, the light emitting element of the semiconductor relay 34, the light emitting element of the semiconductor relay 31, and the first light emitting element 12b, which emit light by the first instruction signal, are connected in series. The order of series connection does not matter. Further, since the first instruction signal is output from the first constant current diode 14e only when the AC signal is full-wave rectified by the diode bridge 14a, the first rectifier circuit 14 is a single-phase AC power supply 10. The first instruction signal is output only during the period when the AC signal from is input. Further, the cathode side of the last-stage light emitting element (first light emitting element 12b in FIG. 1) that emits light by the first instruction signal is connected to the negative electrode side of the first rectifier circuit 14.

The second rectifier circuit 15 is a circuit that rectifies an AC signal from the single-phase AC power supply 10. Further, the second rectifier circuit 15 outputs a second instruction signal when the single-phase reversible motor 11 is rotated in the second direction. As shown in FIG. 1, the second rectifier circuit 15 includes a diode bridge 15a, a step-down resistor 15b, a constant voltage diode 15c, a capacitor 15d, and a second constant current diode 15e. The second instruction signal is output from the second rectifier circuit 15 via the second constant current diode 15e. The method of connecting the light emitting elements that emit light by the second instruction signal is not limited, but it is preferable that the light emitting elements are connected in series. For example, in FIG. 1, the light emitting element of the semiconductor relay 32 that emits light by the second instruction signal, the light emitting element of the semiconductor relay 33, and the second light emitting element 13b are connected in series. The order of series connection does not matter. Further, the cathode side of the last-stage light emitting element (second light emitting element 13b in FIG. 1) that emits light by the second instruction signal is connected to the negative electrode side of the second rectifier circuit 15. The diode bridge 15a, step-down resistance 15b, constant voltage diode 15c, capacitor 15d, and second constant current diode 15e are used in the diode bridge 14a, step-down resistance 14b, constant voltage diode 14c, capacitor 14d, and first constant current diode 14e, respectively. Corresponding ones, detailed description thereof will be omitted.

The first rectifier circuit 14 may return the state of the first instruction signal to a control means such as a CPU. In that case, the first rectifier circuit 14 may include an a-contact semiconductor relay that operates by the first instruction signal. The output of the semiconductor relay will be returned to the control means. Further, a DC signal obtained by converting an AC signal from the single-phase AC power supply 10 into a DC by an AC / DC converter is input to the semiconductor relay, and when the DC signal is closed by the first instruction signal, the DC signal is used as a control means. It may be output to. From the output of the semiconductor relay, the control means can know the state of the first instruction signal, and as a result, can also know the open / closed state of the first open / close circuit 12. The same applies to the second rectifier circuit 15.

The switch 16 is connected to the single-phase AC power supply 10 and the semiconductor relays 31 and 33, and is turned on when the single-phase reversible motor 11 rotates. Therefore, when the single-phase reversible motor 11 is rotating, AC power is supplied to the semiconductor relays 31 and 33 via the switch 16, and when the single-phase reversible motor 11 is stopped, the semiconductor relay 31 , 33, the supply of AC power to 33 will be cut off by the switch 16. The switch 16 may be turned on only during the period from the start of rotation of the single-phase reversible motor 11 to the end of rotation for one tap.

The switch 17 is arranged between the single-phase AC power supply 10 and the third switching circuit 18, is turned on when the tap changer 1 is automatically controlled, and is opened when the tap changer 1 is not automatically controlled. Therefore, in the case of automatic control, the single-phase AC power supply 10 is supplied to the third switching circuit 18.

The third switching circuit 18 is a circuit shown in FIG. 2, and includes NOT elements 18a to 18c and a-contact semiconductor relays 18d and 18e. The cathode side of each light emitting element included in the semiconductor relays 18d and 18e is connected to an insulating ground.

The 90_1 / 2 signal is a signal that becomes a high level (H) when the single-phase reversible motor 11 is rotated in the first direction and becomes a low level (L) when it is rotated in the second direction. Which direction the single-phase reversible motor 11 is rotated depends on the power transmission direction in the SVR. For example, in the case of forward power transmission in SVR, the single-phase reversible motor 11 is rotated in the first direction when the voltage on the secondary side is boosted, and the single-phase reversible motor 11 is rotated in the second direction when the voltage is stepped down. In the case of reverse power transmission, the single-phase reversible motor 11 may be rotated in the second direction when the voltage on the primary side is boosted, and the single-phase reversible motor 11 may be rotated in the first direction when the voltage is stepped down. Good. The 90_1 / 2 signal is input to the NOT elements 18a and 18c, respectively. The 90ENB signal is usually H, and is a signal that becomes L when tap switching is performed. The 90ENB signal is an enable signal used to control whether or not the NOT elements 18a to 18c are operated. When the 90ENB signal is H, the NOT elements 18a to 18c do not operate and the 90ENB signal is L. In that case, the NOT elements 18a to 18c will operate. The 90_1 / 2 signal and the 90ENB signal may be input from, for example, the control means controlling the tap changer 1. When the control is performed by using software, the control means may be configured by, for example, a CPU or the like.

The semiconductor relay 18d is arranged between the switch 17 and the semiconductor relay 32, and a signal from the NOT element 18b is input to the light emitting element of the semiconductor relay 18d. Therefore, the semiconductor relay 18d is closed when the signal from the NOT element 18b becomes H, and opens when the signal becomes L. The semiconductor relay 18d temporarily supplies the AC signal of the single-phase AC power supply 10 to the first rectifier circuit 14 when the single-phase reversible motor 11 is rotated in the first direction by automatic control. "Temporarily" means at least until the supply of the AC signal by the self-holding circuit described later starts. Further, the semiconductor relay 18e is arranged between the switch 17 and the semiconductor relay 34, and a signal from the NOT element 18c is input to the light emitting element of the semiconductor relay 18e. Therefore, the semiconductor relay 18e is closed when the signal from the NOT element 18c becomes H, and opens when the signal becomes L. The semiconductor relay 18e temporarily supplies the AC signal of the single-phase AC power supply 10 to the second rectifier circuit 15 when the single-phase reversible motor 11 is rotated in the second direction by automatic control. Therefore, when rotating the single-phase reversible motor 11 in the first direction, the 90_1 / 2 signal is first set to H, and then the 90ENB signal is changed from H to L. As a result, each of the NOT elements 18a to 18c operates, and a high level signal is input to the light emitting element of the semiconductor relay 18d, but a low level signal is input to the light emitting element of the semiconductor relay 18e. , Only the semiconductor relay 18d is closed, and the AC signal is supplied to the semiconductor relay 32. As will be described later, after the AC signal is supplied to the first rectifier circuit 14 via the semiconductor relay 18d, the supply of the AC current to the first rectifier circuit 14 is self-held, so that self-holding is performed. After, the 90ENB signal may be returned to H. Further, after the self-holding, the 90_1 / 2 signal may also become L. When rotating the single-phase reversible motor 11 in the second direction, the 90_1 / 2 signal is first set to L, and then the 90ENB signal is changed from H to L. As a result, each of the NOT elements 18a to 18c operates, and a high level signal is input to the light emitting element of the semiconductor relay 18e, but a low level signal is input to the light emitting element of the semiconductor relay 18d. , Only the semiconductor relay 18e is closed, and the AC signal is supplied to the semiconductor relay 34. As will be described later, after the AC signal is supplied to the second rectifier circuit 15 via the semiconductor relay 18e, the supply of the AC current to the second rectifier circuit 15 is self-held, so that self-holding is performed. After, the 90ENB signal may be returned to L.

The open / closed state of the semiconductor relays 18d and 18e may be returned to a control means such as a CPU. In that case, the third switching circuit 18 may include an a-contact semiconductor relay operated by the output of the NOT element 18b and an a-contact semiconductor relay operated by the output of the NOT element 18c. The output of those semiconductor relays will be returned to the control means. Further, when a DC signal from an AC / DC converter that converts an AC signal into a DC signal is input to these semiconductor relays and closed by an output from the NOT elements 18b and 18c, the DC signal is used as a control means. It may be output to. The output of the semiconductor relay enables the control means to know the open / closed state of the semiconductor relays 18d and 18e.

The switch 19 is arranged between the single-phase AC power supply 10 and the step-up switch 20 and the step-down switch 21, is turned on when the tap changer 1 is manually controlled, and is opened when the tap changer 1 is not manually controlled. Therefore, in the case of manual control, the single-phase AC power supply 10 is supplied to the step-up switch 20 and the step-down switch 21.

The boost switch 20 is arranged between the switch 19 and the fourth switching circuit 22, and when the single-phase reversible motor 11 is rotated to the boost side by manual control, the AC signal of the single-phase AC power supply 10 is temporarily set. 4 Supply to the opening / closing circuit 22. Therefore, the step-up switch 20 is temporarily turned on when the step-up is performed by manual control, and is opened in other cases.

The step-down switch 21 is arranged between the switch 19 and the fourth open / close circuit 22, and when the single-phase reversible motor 11 is rotated to the step-down side by manual control, the AC signal of the single-phase AC power supply 10 is temporarily set. 4 Supply to the opening / closing circuit 22. Therefore, the step-down switch 21 is temporarily turned on when the step-down is performed by manual control, and is opened in other cases.

The fourth switching circuit 22 is, for example, the circuit shown in FIG. 3, and is a signal output unit 22a, an a-contact semiconductor relay 22b, a b-contact semiconductor relay 22c, an a-contact semiconductor relay 22d, and a b-contact semiconductor relay 22e. And. The cathode side of each light emitting element included in the semiconductor relays 22b to 22e is connected to an insulating ground.

The signal output unit 22a outputs the first and second reverse power transmission signals when the power transmission direction in the SVR is reverse power transmission, and does not output the first and second reverse power transmission signals when the power transmission direction is forward power transmission. The first reverse power transmission signal is input to the light emitting elements of the b-contact semiconductor relays 22c and 22e, and the second reverse power transmission signal is input to the light emitting elements of the a-contact semiconductor relays 22b and 22d. The first and second reverse power transmission signals are signals for causing each light emitting element included in the semiconductor relays 22b to 22e to emit light.

The a-contact semiconductor relay 22b is arranged between the boost switch 20 and the second rectifier circuit 15, and operates in response to the second reverse power transmission signal input at the time of reverse power transmission. That is, the a-contact semiconductor relay 22b is closed when the second reverse power transmission signal is input, and is opened when the second reverse power transmission signal is not input.

The b-contact semiconductor relay 22c is arranged between the boost switch 20 and the first rectifier circuit 14, and operates in response to the first reverse power transmission signal input at the time of reverse power transmission. That is, the b-contact semiconductor relay 22c is opened when the first reverse power transmission signal is input, and closed when the first reverse power transmission signal is not input.

The a-contact semiconductor relay 22d is arranged between the step-down switch 21 and the first rectifier circuit 14, and operates in response to a second reverse power transmission signal input during reverse power transmission. That is, the a-contact semiconductor relay 22d is closed when the second reverse power transmission signal is input, and is opened when the second reverse power transmission signal is not input.

The b-contact semiconductor relay 22e is arranged between the step-down switch 21 and the second rectifier circuit 15, and operates in response to the first reverse power transmission signal input at the time of reverse power transmission. That is, the b-contact semiconductor relay 22e is opened when the first reverse power transmission signal is input, and closed when the first reverse power transmission signal is not input.

When the first and second reverse power transmission signals are not output from the signal output unit 22a, that is, in the case of forward power transmission, the a-contact semiconductor relays 22b and 22d are opened, and the b-contact semiconductor relays 22c and 22e are closed. Will be there. Therefore, when the step-up switch 20 is turned on, an AC signal is supplied to the first rectifier circuit 14, the single-phase reversible motor 11 is rotated in the first direction, and when the step-down switch 21 is turned on, the second rectification is performed. An AC signal is supplied to the circuit 15, and the single-phase reversible motor 11 is rotated in the second direction. On the other hand, when the first and second reverse power transmission signals are output from the signal output unit 22a, that is, in the case of reverse power transmission, the a-contact semiconductor relays 22b and 22d are closed and the b-contact semiconductor relays 22c and 22e are opened. Will be. Therefore, when the step-up switch 20 is turned on, an AC signal is supplied to the second rectifier circuit 15, the single-phase reversible motor 11 is rotated in the second direction, and when the step-down switch 21 is turned on, the first rectification is performed. An AC signal is supplied to the circuit 14, and the single-phase reversible motor 11 is rotated in the first direction.

Here, the operation timings of the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e may be different. For example, it is conceivable that the a-contact semiconductor relays 22b and 22d have earlier operation timings than the b-contact semiconductor relays 22c and 22e, and the b-contact semiconductor relays 22c and 22e are more than the a-contact semiconductor relays 22b and 22d. It is also possible that the operation timing is early. Therefore, when both are controlled by the same signal, all the semiconductor relays 22b to 22e are temporarily closed, and when the step-up switch 20 or the step-down switch 21 is turned on, the first of the single-phase reversible motor 11 The single-phase AC power supply 10 is supplied to both the first and second terminals 11d and 11e, which may cause the single-phase reversible motor 11 to fail. Therefore, it is preferable that the first and second reverse power transmission signals are output so that both the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e are not closed at the same time. Therefore, the signal output unit 22a outputs the first reverse power transmission signal first when the forward power transmission is changed to the reverse power transmission in the SVR, then outputs the second reverse power transmission signal, and the reverse power transmission is changed to the forward power transmission. At this time, the output of the second reverse power transmission signal may be stopped first, and then the output of the first reverse power transmission signal may be stopped. Assuming that the time difference between the operation timings of the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e is TD, the signal output unit 22a is the first after TD or more has elapsed after outputting the first reverse power transmission signal. 2 The output of the reverse power transmission signal may be output, and the output of the first reverse power transmission signal may be stopped after TD or more has elapsed after the output of the second reverse power transmission signal is stopped. Further, for example, the period from the output of the first reverse power transmission signal to the output of the second reverse power transmission signal and the period from the stop of the output of the second reverse power transmission signal to the stop of the output of the first reverse power transmission signal are defined as TD + ε. In some cases, ε is preferably a small positive value. This is because it is preferable that the operation timings of the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e do not deviate too much. When the signal output unit 22a outputs the first and second reverse transmission signals as described above, the operation timing of the a-contact semiconductor relays 22b and 22d and the operation timing of the b-contact semiconductor relays 22c and 22e are earlier. Even if there is, it is possible to prevent both semiconductor relays from being closed at the same time.

FIG. 4 is a timing chart showing an example of the first and second reverse power transmission signals and the states of the semiconductor relays 22b to 22e. In FIG. 4, it is assumed that the b-contact semiconductor relay has a later operation timing than the a-contact semiconductor relay. In FIGS. 4A and 4B, the rising edge of the second reverse power transmission signal shown by the solid line, that is, the output timing of the second reverse power transmission signal is the rising edge of the first reverse power transmission signal, that is, the first reverse power transmission signal. It is later than the output timing of. Therefore, in FIGS. 4 (c) and 4 (d), the timing at which the a-contact semiconductor relays 22b and 22d shown by the solid line are turned on is later than the timing at which the b-contact semiconductor relays 22c and 22e are opened. Therefore, it is possible to prevent both semiconductor relays from being turned on at the same time. On the other hand, if such timing adjustment is not performed, the second reverse power transmission signal is output as shown by the broken line in FIG. 4B, and the a-contact semiconductor relays 22b and 22d are turned on. As shown by the broken line in FIG. 4D, the timing is earlier than the timing at which the b-contact semiconductor relays 22c and 22e are opened. As a result, there is a period in which both semiconductor relays are temporarily turned on at the same time, and when the step-up switch 20 or the step-down switch 21 is turned on during that period, the first single-phase reversible motor 11 and AC power will be supplied to both the second terminals 11d and 11e, and the single-phase reversible motor 11 will fail. By appropriately controlling the first and second reverse power transmission signals in this way, it becomes possible to prevent such a failure of the single-phase reversible motor 11.

In the above description, the case where the output timings of the first and second reverse power transmission signals are changed both when the forward power transmission is changed to the reverse power transmission and when the reverse power transmission is changed to the forward power transmission has been described. , It doesn't have to be. For example, when it is known which of the operation timing of the a-contact semiconductor relay and the operation timing of the b-contact semiconductor relay is earlier, when the forward power transmission is changed to the reverse power transmission and when the reverse power transmission is changed to the forward power transmission. Only one of them may be used to change the timing of the first and second reverse power transmission signals. Specifically, when the operation timing of the b-contact semiconductor relay is later than that of the a-contact semiconductor relay, the signal output unit 22a precedes the first reverse power transmission signal when the forward power transmission is changed to the reverse power transmission. Then, the second reverse power transmission signal may be output to, and when the reverse power transmission is changed to the forward power transmission, the output of the first and second reverse power transmission signals may be stopped at the same time. Further, when the operation timing of the a-contact semiconductor relay is later than that of the b-contact semiconductor relay, the signal output unit 22a transmits the first and second reverse power transmission signals when the forward power transmission is changed to the reverse power transmission. When the power is output at the same time and the reverse power transmission is changed to the forward power transmission, the output of the second reverse power transmission signal may be stopped first, and then the output of the first reverse power transmission signal may be stopped.

The semiconductor relay 31 is an a-contact semiconductor relay that is connected to the switch 16 and supplies an AC signal from the single-phase AC power supply 10 supplied via the switch 16 to the first rectifier circuit 14 in response to the first instruction signal. Is. That is, the semiconductor relay 31 is closed when the first instruction signal is input, and is opened otherwise. In FIG. 1, the positive electrode side of the first rectifier circuit 14 is connected to the anode side of the light emitting element of the semiconductor relay 31 via the light emitting element of the semiconductor relay 34. When an AC signal is supplied to the first rectifier circuit 14 even temporarily, the single-phase reversible motor 11 starts rotating accordingly, the switch 16 is turned on, and the semiconductor relay 31 is closed. It will be. As a result, even if the AC signal is not supplied from the third switching circuit 18 or the fourth switching circuit 22 to the first rectifying circuit 14, the AC signal is supplied to the first rectifying circuit 14 via the semiconductor relay 31. Become. Therefore, the semiconductor relay 31 is a circuit that self-holds the supply of the AC signal to the first rectifier circuit 14.

The semiconductor relay 32 is a b-contact semiconductor relay arranged between the third switching circuit 18, the fourth switching circuit 22, and the semiconductor relay 31 and the first rectifying circuit 14. The semiconductor relay 32 supplies an AC signal to the first rectifier circuit 14 in response to the second instruction signal. That is, the semiconductor relay 32 is opened when the second instruction signal is input, and closed otherwise. In FIG. 1, the positive electrode side of the second rectifier circuit 15 is connected to the anode side of the light emitting element of the semiconductor relay 32. When the second instruction signal is output from the second rectifier circuit 15, the single-phase AC power supply 10 is supplied to the second terminal 11e of the single-phase reversible motor 11, so that the second instruction signal causes the semiconductor relay 32 to operate. By opening the rectifier circuit 14 and preventing the first rectifier circuit 14 from operating, it is possible to prevent the single-phase AC power supply 10 from being supplied to the first terminal 11d and prevent the single-phase reversible motor 11 from failing. Can be done.

The semiconductor relay 33 is an a-contact semiconductor relay that is connected to the switch 16 and supplies an AC signal from the single-phase AC power supply 10 supplied via the switch 16 to the second rectifier circuit 15 in response to the second instruction signal. Is. That is, the semiconductor relay 33 is closed when the second instruction signal is input, and is opened otherwise. In FIG. 1, the positive electrode side of the second rectifier circuit 15 is connected to the anode side of the light emitting element of the semiconductor relay 33 via the light emitting element of the semiconductor relay 32. The semiconductor relay 33 corresponds to the semiconductor relay 31 provided on the second rectifier circuit 15 side, and detailed description thereof will be omitted.

The semiconductor relay 34 is a b-contact semiconductor relay arranged between the third switching circuit 18, the fourth switching circuit 22, the semiconductor relay 33, and the second rectifier circuit 15. The semiconductor relay 34 supplies an AC signal to the second rectifier circuit 15 in response to the first instruction signal. That is, the semiconductor relay 34 is opened when the first instruction signal is input, and closed otherwise. In FIG. 1, the positive electrode side of the first rectifier circuit 14 is connected to the anode side of the light emitting element of the semiconductor relay 34. The semiconductor relay 34 corresponds to the semiconductor relay 32 provided on the second rectifier circuit 15 side, and detailed description thereof will be omitted.

Each of the semiconductor relays 18d, 18e, 22b to 22e, and 31 to 34 has an input side circuit having a light emitting element and an output side circuit having a semiconductor switch that turns on or off when the light emitting element emits light. It may be a photoMOS relay, for example, and is configured by using a triac, a light emitting element, and a phototriac as in the first switching circuit 12 and the second switching circuit 13. It may be a semiconductor relay, or it may be a semiconductor relay having other configurations. Since a large current does not flow through these semiconductor relays 18d, 18e, 22b to 22e, 31 to 34, a low-capacity semiconductor relay such as a photoMOS relay can be used. Further, the tap changer 1 is a varistor (1) arranged in parallel with the semiconductor relays 18d, 18e, 22b to 22e, 31 to 34 in order to protect the semiconductor relays 18d, 18e, 22b to 22e, 31 to 34 from overvoltage. (Not shown) may have. Providing a varistor in parallel with the semiconductor relay may mean providing a varistor in parallel with the output side circuit of the semiconductor relay. By connecting a varistor that operates between the working voltage of the semiconductor element and the absolute rated voltage in parallel with the semiconductor element, the varistor operates before reaching the absolute rated voltage when an overvoltage is applied, and a current flows. Will protect the semiconductor element. Therefore, it is preferable that the varistor connected in parallel with the semiconductor relay operates between the working voltage of the semiconductor relay and the absolute rated voltage. Further, the light emitting element included in the input side circuit of the semiconductor relay may be an LED. Further, the semiconductor relay may be other than those described above as long as it is composed of semiconductor elements.

The limit switch 35 is a b-contact switch that is opened when the single-phase reversible motor 11 rotating in the first direction rotates beyond the tap at the end. By this limit switch 35, it is possible to prevent the single-phase reversible motor 11 from rotating in the first direction beyond the tap at the end.

The limit switch 36 is a b-contact switch that is opened when the single-phase reversible motor 11 rotating in the second direction rotates beyond the terminal tap. The limit switch 36 can prevent the single-phase reversible motor 11 from rotating in the second direction beyond the terminal tap.

It should be noted that the light emitting elements of the semiconductor relays 18d, 18e, 22b to 22e, 31 to 34, and the first and second light emitting elements 12b, 13b of the first and second switching circuits 12, 13 have resistors for preventing erroneous lighting. May be provided in parallel, or a noise removing capacitor may be provided in parallel.

Next, the operation of the tap changer 1 according to the present embodiment will be described. First, a case where automatic control is performed will be described. In this case, it is assumed that the switch 17 is turned on and the switch 19 is opened. It is assumed that the SVR having the tap changer 1 has forward power transmission, and it is necessary to boost the secondary side for voltage adjustment. Then, it is assumed that the control means (not shown) sets the 90_1 / 2 signal to H and then changes the 90ENB signal from H to L. Then, the semiconductor relay 18d is closed, but the semiconductor relay 18e remains open. As a result, the AC signal is supplied to the first rectifier circuit 14 via the semiconductor relay 18d, and the first instruction signal is output from the first rectifier circuit 14 to the first switching circuit 12 and the semiconductor relays 31 and 34. In response to the output of the first instruction signal, the a-contact semiconductor relay 31 is turned on, and the b-contact semiconductor relay 34 is opened, so that the supply of the AC signal to the second rectifier circuit 15 is reliably blocked. It will be. Further, the first light emitting element 12b emits light in response to the output of the first instruction signal, and the AC signal flows in the first triac 12a in response to the AC signal flowing in the first photo triac 12c. As a result, the single-phase AC power supply 10 is supplied to the first terminal 11d, and the single-phase reversible motor 11 rotates in the first direction. The switch 16 is turned on according to the rotation. Further, since the semiconductor relay 31 is turned on in response to the output of the first instruction signal, the AC signal is supplied to the first rectifier circuit 14 via the switch 16 and the semiconductor relays 31 and 32. As described above, after the AC signal is supplied to the first rectifier circuit 14 by the self-holding circuit, the control means sets the 90_1 / 2 signal and the 90ENB signal as the initial state signals L and H, respectively. Return to. As a result, both the semiconductor relays 18d and 18e are opened, but the supply of the AC signal to the first rectifier circuit 14 is continued via the self-holding circuit.

When the single-phase reversible motor 11 rotates in the first direction by one tap, the switch 16 is opened. When the switch 16 is opened, the supply of the AC signal to the first rectifier circuit 14 is cut off, and the output of the first instruction signal is stopped. As a result, the supply of the AC power supply via the first switching circuit 12 is cut off, so that the single-phase reversible motor 11 stops. In addition, the semiconductor relays 31 and 34 will return to their initial states, respectively.

When adjusting the step-down voltage in SVR, a control means (not shown) sets the 90_1 / 2 signal to L, and then changes the 90ENB signal from H to L. Then, the semiconductor relay 18d remains open, but the semiconductor relay 18e is closed. Then, an AC signal is supplied to the second rectifier circuit 15 via the semiconductor relay 18e, and the second instruction signal is output from the second rectifier circuit 15 to the second opening / closing circuit 13 and the semiconductor relays 32 and 33. In response to the output of the second instruction signal, the a-contact semiconductor relay 33 is turned on, and the b-contact semiconductor relay 32 is opened, so that the supply of the AC signal to the first rectifier circuit 14 is reliably blocked. It will be. Further, the second light emitting element 13b emits light in response to the output of the second instruction signal, and the AC signal flows in the second triac 13a in response to the AC signal flowing in the second photo triac 13c. As a result, the single-phase AC power supply 10 is supplied to the second terminal 11e, and the single-phase reversible motor 11 rotates in the second direction. The switch 16 is turned on in response to the rotation, and the AC signal is supplied to the second rectifier circuit 15 via the self-holding circuit. After that, the control means returns the 90_1 / 2 signal and the 90ENB signal to L and H, which are the signals in the initial state, respectively.

When the single-phase reversible motor 11 rotates in the second direction by one tap, the switch 16 is opened. When the switch 16 is opened, the supply of the AC signal to the second rectifier circuit 15 is cut off, and the output of the second instruction signal is stopped. As a result, the supply of the AC power supply via the second switching circuit 13 is cut off, so that the single-phase reversible motor 11 stops. Further, the semiconductor relays 32 and 33 each return to the initial state.

Next, a case where manual control is performed will be described. In this case, it is assumed that the switch 19 is turned on and the switch 17 is opened. Further, it is assumed that the SVR having the tap changer 1 is forward power transmission. Then, since the first and second reverse power transmission signals are not output from the signal output unit 22a, the a-contact semiconductor relays 22b and 22d are open, and the b-contact semiconductor relays 22c and 22e are turned on. In such a state, it is assumed that it becomes necessary to boost the secondary side of the SVR. Then, it is assumed that the operator or the like turns on the step-up switch 20 manually or remotely. When the step-up switch 20 is turned on, an AC signal is supplied to the semiconductor relay 32 via the b-contact semiconductor relay 22c. Subsequent operations are the same as when the semiconductor relay 18d is closed during automatic control, and the description thereof will be omitted. The boost switch 20 may be opened after the single-phase reversible motor 11 starts rotating in the first direction. This is because the self-holding circuit continues to supply the AC signal to the first rectifier circuit 14. The single-phase reversible motor 11 stops when it rotates in the first direction by one tap. Further, it is assumed that it becomes necessary to step down the secondary side of the SVR, and the operator or the like turns on the step-down switch 21 manually or remotely. When the step-down switch 21 is turned on, an AC signal is supplied to the semiconductor relay 34 via the b-contact semiconductor relay 22e. Subsequent operations are the same as when the semiconductor relay 18e is closed during automatic control, and the description thereof will be omitted. The single-phase reversible motor 11 stops when it rotates in the second direction by one tap. Further, it is assumed that the SVR having the tap changer 1 has changed from forward power transmission to reverse power transmission. Then, in response to the detection of the change in the power transmission direction, the signal output unit 22a first outputs the first reverse power transmission signal to the b-contact semiconductor relays 22c and 22e, and then outputs the second reverse power transmission signal to the a-contact semiconductor relay. Output to 22b and 22d. As a result, the b-contact semiconductor relays 22c and 22e are opened, and then the a-contact semiconductor relays 22b and 22d are turned on. In the case of reverse power transmission, since the substation exists on the secondary side, the target of voltage adjustment in SVR is the primary side. In such a state, it is assumed that it becomes necessary to boost the primary side of the SVR. Then, when the operator or the like manually or remotely controls the boost switch 20, an AC signal is supplied to the semiconductor relay 34 via the a-contact semiconductor relay 22b accordingly. Subsequent operations are the same as when the semiconductor relay 18e is closed during automatic control, and the description thereof will be omitted. Further, it is assumed that it is necessary to step down the primary side of the SVR at the time of reverse power transmission, and the operator or the like turns on the step-down switch 21 manually or remotely. When the step-down switch 21 is turned on, an AC signal is supplied to the semiconductor relay 32 via the a-contact semiconductor relay 22d. Subsequent operations are the same as when the semiconductor relay 18d is closed during automatic control, and the description thereof will be omitted.

As described above, according to the tap changer 1 according to the present embodiment, by using a semiconductor relay or the like instead of the mechanical relay, the mechanical moving parts are reduced and the life is extended. In addition, it is more resistant to vibration and shock than when a mechanical relay is used. Further, since the tap changer 1 composed of semiconductor elements operates in the same manner as the tap changer using the conventional mechanical relay, the conventional tap changer can be easily converted into the tap changer 1 according to the present embodiment. It can also be replaced. Further, since the first and second switching circuits 12 and 13 are configured by using the first and second triacs 12a and 13a and the first and second phototriacs 12c and 13c, they are used in the single-phase reversible motor 11. It becomes possible to control the opening and closing of high-current alternating current. Further, conventionally, there is no semiconductor relay in which both the input side and the output side are alternating current, but the first and second rectifier circuits 14 and 15 for outputting the first and second instruction signals are provided on the input side, and the first By controlling the first and second switching circuits 12 and 13 by the second instruction signal, the output of the AC power supply can be controlled as a whole according to the input of the AC signal. Further, since the tap changer 1 is provided with the first and second rectifier circuits 14 and 15, even if the AC / DC converter in the SVR fails, at least the tap changer 1 can be operated by manual control. Will be able to. When the AC / DC converter of the SVR fails, the DC power is not supplied to the control means or the like, so that the AC signal is not output from the third switching circuit 18, and the first and second signals output units 22a do not output the AC signal. The reverse power transmission signal is no longer output. On the other hand, since the AC signal can be supplied via the b-contact semiconductor relays 22c and 22e in the fourth switching circuit 22, the single-phase reversible motor 11 can be first operated by operating the step-up switch 20 and the step-down switch 21. It can be rotated in a direction or a second direction. Therefore, as described above, even if the AC / DC converter used as the DC power supply fails, at least the step-up or step-down can be performed by manual control. Further, by providing the first and second constant current diodes 14e and 15e on the output sides of the first and second rectifier circuits 14 and 15, respectively, the first and second instruction signals have a predetermined current. Can be. As a result, the light emission of the light emitting element in the semiconductor relay or the like by the first and second instruction signals can be stabilized, and the semiconductor relay or the like can be operated stably. Further, in the fourth switching circuit 22, the first and second reverse power transmission signals are output so that both the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e are not closed at the same time. , It is possible to avoid the failure of the single-phase reversible motor 11 due to the simultaneous supply of AC signals to both the first and second rectifier circuits 14 and 15.

In the present embodiment, the configuration in which the tap changer 1 does not include the mechanical relay has been described, but it may not be the case. Also in the tap changer 1, a mechanical relay may be used for a relay that is used infrequently. This is because the life of the device can be extended by configuring the relay, which is frequently used, with semiconductor elements. For example, when the direction of the substation does not change so much, the a-contact mechanical relay may be used instead of the a-contact semiconductor relays 22b and 22d in the fourth switching circuit 22, and the b-contact semiconductor relays 22c and 22e may be used. A b-contact mechanical relay may be used instead of. Even in that case, as described above, it is preferable that the first and second reverse power transmission signals are output so that both the a-contact mechanical relay and the b-contact mechanical relay are not closed at the same time.

Further, in the present embodiment, the case where the timings of the first and second reverse power transmission signals input to the respective semiconductor relays 22b to 22e are changed in the fourth switching circuit 22 has been described, but even if it is not the case. Good. For example, when the operation timings of the a-contact semiconductor relays 22b and 22d and the b-contact semiconductor relays 22c and 22e are the same, all the semiconductor relays 22b to 22e may be controlled by one reverse power transmission signal. ..

Further, in the present embodiment, the case where the first and second rectifier circuits 14 and 15 output the first and second instruction signals via the first and second constant current diodes 14e and 15e, respectively, has been described. But it doesn't have to be. When the semiconductor relay or the like can be operated stably even if the first and second instruction signals are not output via the constant current diode, the first and second rectifier circuits 14 and 15 are the first. And the second constant current diodes 14e and 15e may not be provided.

Further, in the present embodiment, the case where the first and second rectifier circuits 14 and 15 have the configuration shown in FIG. 1 has been described, but it is not necessary. For example, rectification may be performed by a configuration other than the diode bridges 14a and 15a, and the DC voltage may be divided by a configuration other than the step-down resistors 14b and 15b and the constant voltage diodes 14c and 15c. For example, a resistor may be used instead of the zener diodes 14c and 15c.

Further, in the present embodiment, the case where the first and second switching circuits 12 and 13 have the triac, the light emitting element, and the photo triac has been described, but it is not necessary. If the supply of AC power required for the operation of the single-phase reversible motor 11 can be controlled, the first and second terminals of the single-phase reversible motor 11 are provided by other first and second switching circuits composed of semiconductor elements. The supply of AC power to 11d and 11e may be controlled.

Further, in the above embodiment, each process or each function may be realized by centralized processing by a single device or a single system, or distributed processing by a plurality of devices or a plurality of systems. It may be realized by.

Further, it goes without saying that the present invention is not limited to the above embodiments, and various modifications can be made, and these are also included in the scope of the present invention.

From the above, the tap changer according to the present invention has the effect of having a longer life and being resistant to vibration and shock, and is useful as a tap changer for switching taps of an adjustment transformer of an automatic voltage regulator. ..

1 Tap switching device 11 Single-phase reversible motor 12 1st switching circuit 12a 1st triac 12b 1st light emitting element 12c 1st photo triac 13 2nd opening / closing circuit 13a 2nd triac 13b 2nd light emitting element 13c 2nd photo triac 14 1st Rectifier circuit 14e 1st constant current diode 15 2nd rectifier circuit 15e 2nd constant current diode 16, 17, 19 switches 18d, 18e, 31, 32, 33, 34 Semiconductor relay 20 Boost switch 21 Step-down switch 22a Signal output unit 22b, 22d a contact semiconductor relay 22c, 22eb contact semiconductor relay

Claims (6)

It is a motor that switches the energizing tap of the adjusting transformer used in the automatic voltage regulator, has first and second terminals, and rotates in the first direction when a single-phase AC power supply is supplied to the first terminal. A single-phase reversible motor, which is a motor that rotates in the second direction when a single-phase AC power supply is supplied to the second terminal.
A first rectifier circuit that rectifies an AC signal from the single-phase AC power supply and outputs a first instruction signal when the single-phase reversible motor is rotated in the first direction.
A second rectifier circuit that rectifies an AC signal from the single-phase AC power supply and outputs a second instruction signal when the single-phase reversible motor is rotated in the second direction.
A first switching circuit, which is a circuit that controls the supply of the single-phase AC power supply to the first terminal in response to the first instruction signal, and is a circuit configured by using a semiconductor element.
Tap switching including a second switching circuit, which is a circuit that controls the supply of the single-phase AC power supply to the second terminal in response to the second instruction signal and is a circuit configured by using a semiconductor element. apparatus. The first switching circuit
A first triac arranged between the single-phase AC power supply and the first terminal,
The first light emitting element that emits light by the first instruction signal and
A first photo triac that supplies an AC signal from the single-phase AC power supply to the gate of the first triac when receiving light from the first light emitting element is provided.
The second opening / closing circuit
A second triac arranged between the single-phase AC power supply and the second terminal,
A second light emitting element that emits light by the second instruction signal and
The tap switching according to claim 1, further comprising a second phototriac that supplies an AC signal from the single-phase AC power source to the gate of the second triac when receiving light from the second light emitting element. apparatus. The first and second rectifier circuits have first and second constant current diodes, respectively.
The first instruction signal is output from the first rectifier circuit via the first constant current diode.
The tap switching device according to claim 1 or 2, wherein the second instruction signal is output from the second rectifier circuit via the second constant current diode. A semiconductor relay that temporarily supplies an AC signal of the single-phase AC power supply to the first rectifier circuit when the single-phase reversible motor is rotated in the first direction by automatic control.
A semiconductor relay that temporarily supplies an AC signal of the single-phase AC power supply to the second rectifier circuit when the single-phase reversible motor is rotated in the second direction by automatic control.
A switch that is connected to the single-phase AC power supply and is turned on when the single-phase reversible motor rotates.
A semiconductor relay connected to the switch and supplying an AC signal from the single-phase AC power supply supplied via the switch to the first rectifier circuit in response to the first instruction signal.
A semiconductor relay connected to the switch and supplying an AC signal from the single-phase AC power supply supplied via the switch to the second rectifier circuit in response to the second instruction signal.
The tap changer according to any one of claims 1 to 3, further comprising a varistor arranged in parallel with each of the semiconductor relays. In the case of forward power transmission in the automatic voltage regulator, the rotations of the single-phase reversible motor in the first and second directions are the rotations of the step-up side and the step-down side, respectively.
A boost switch that temporarily supplies the AC signal of the single-phase AC power supply when the single-phase reversible motor is rotated to the boost side by manual control.
A step-down switch that temporarily supplies the AC signal of the single-phase AC power supply when the single-phase reversible motor is rotated to the step-down side by manual control.
A b-contact semiconductor relay that is arranged between the boost switch and the first rectifier circuit and operates in response to a first reverse power transmission signal input during reverse power transmission.
A b-contact semiconductor relay that is arranged between the step-down switch and the second rectifier circuit and operates in response to the first reverse power transmission signal.
An a-contact semiconductor relay that is arranged between the boost switch and the second rectifier circuit and operates in response to a second reverse power transmission signal input during reverse power transmission.
An a-contact semiconductor relay that is arranged between the step-down switch and the first rectifier circuit and operates in response to the second reverse power transmission signal.
A signal output unit that outputs the first and second reverse power transmission signals when the power transmission direction in the automatic voltage regulator is reverse power transmission is further provided.
Claims 1 to 4, wherein the signal output unit outputs the first and second reverse transmission signals so that both the a-contact semiconductor relay and the b-contact semiconductor relay are not closed at the same time. One of the tap switching devices described. The signal output unit outputs the first reverse power transmission signal first when the forward power transmission is changed to the reverse power transmission, then outputs the second reverse power transmission signal, and when the reverse power transmission is changed to the forward power transmission. The tap switching device according to claim 5, wherein the output of the second reverse power transmission signal is stopped first, and then the output of the first reverse power transmission signal is stopped.

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