JPH0550201B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to an AC voltage generation circuit for an electric vehicle, and in particular to an electric vehicle that can control the DC current flowing through a DC motor for driving and charge a storage battery while driving. The present invention relates to an AC voltage generation circuit for use.

BACKGROUND OF THE INVENTION Conventionally, electric vehicles have been equipped with a storage battery and a DC motor, and are driven by supplying power from the storage battery to the DC motor to rotate it. Hybrid cars are known.
Such electric or hybrid vehicles are
When a DC motor is driven by a storage battery, the running speed is controlled by intermittent current flowing through the DC motor using a chopper circuit. However, if the electric power stored in the storage battery is lost, the vehicle will no longer be able to run using the DC motor, so it is necessary to charge the storage battery before that happens. For this reason, when an electric vehicle or a hybrid vehicle is stopped, AC power is supplied from the outside, and
The voltage is regulated and rectified to obtain DC voltage to charge the storage battery, and while driving, when braking or going down a slope, the rotation of the wheels is transmitted to the DC motor, and this DC motor is operated as a generator. The storage battery is charged by the output of the generator.

By the way, in the current situation where various home appliances have become widespread, there often arises a demand for using electric appliances such as work lights and vacuum cleaners in electric vehicles or hybrid vehicles. However, electrical appliances generally use AC power
Requires AC100V. Such electrical appliances cannot normally be used in electric or hybrid vehicles because there is often no AC power source nearby.

OBJECTIVES OF THE INVENTION Therefore, the main object of the present invention is to provide an AC voltage generation circuit for an electric vehicle that can generate an AC voltage using a chopper circuit and a charging circuit installed in a conventional electric vehicle or hybrid vehicle. That's true.

SUMMARY OF THE INVENTION To summarize this invention, a storage battery, an armature winding of a DC motor, and an intermediate tap of a primary winding of a transformer are connected in series, and first taps are connected on both sides of the primary winding of the transformer.
and a second switching element are connected, the first and second switching elements are switched alternately to operate as a chopper circuit, and the first and second diodes are operated as a freewheel circuit to supply power to the DC motor. The driving speed of the electric vehicle is controlled by intermittent direct current.

In addition, first and second rectifying diodes are connected between both ends of the primary winding of the transformer and the storage battery, and an AC voltage is applied to the secondary winding of the transformer, so that the voltage is stepped down to the primary winding. The alternating current voltage that appears is rectified, and the resulting direct current voltage is used to charge the storage battery.

Further, diodes are connected in parallel to each of the first and second switching elements, and the first and second switching elements are alternately switched to operate as an inverter circuit to generate alternating current voltage from the secondary winding of the transformer. .

The above objects and other objects and features of the present invention will become more apparent from the detailed description given below with reference to the drawings.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 is an electrical circuit diagram of an embodiment of the present invention. First, the configuration will be explained with reference to FIG. A storage battery 1 serving as a power DC power source includes a fuse 2, a first main switch 3, an armature winding 41 of a DC motor 4, a shunt resistor 5, and a transformer 6.
The intermediate taps of the next windings 61 are connected in series.

Further, the intermediate tap of the primary winding 61, the thyristor 7 for charging control (a diode may be used if the charging current is not controlled), the shunt resistor 8, and the storage battery 1 are connected in series. A first rectifying diode 14 is connected between one end of the primary winding 61 and the fuse 2 for passing charging current and freewheeling current to the storage battery 1, and a first rectifying diode 14 is connected between the other end of the primary winding 61 and the fuse 2. Similarly, a second rectifying diode 15 for flowing a freewheeling current and a charging current is connected between the two. Furthermore, the primary winding 61
are connected to transistors 9 and 10, respectively.
, and the cathodes of diodes 11 and 12 are connected to each other. transistors 9 and 10
and each anode of the diodes 11 and 12 are connected to one end of the shunt resistor 8 via the second main switch 13. diode 15
and one end of the shunt resistor 8.
A series circuit consisting of a coil 16 and a capacitor 17 is connected to absorb the surge voltage generated in the next winding 61.

The transformer 6 is provided with a secondary winding 62 . This secondary winding 62 is supplied with an AC voltage from the outside when charging the storage battery 1 . In addition, the secondary winding 6
When the control circuit is operated as an inverter circuit without applying an external AC voltage to the secondary winding 62, an AC voltage is generated across the secondary winding 62. The turns ratio between the primary winding 61 and the secondary winding 62 of the transformer 6 is such that the DC voltage obtained by full-wave rectification of the AC voltage appearing across the primary winding 61 is the DC voltage of the storage battery 1. The voltage is selected to be slightly higher than the voltage.

Next, the operation will be explained. First, an explanation will be given of the operation when the electric vehicle is powered to run by rotationally driving the running DC motor 4. The respective bases of transistors 9 and 10 are alternately correlated to the accelerator pedal position in order to close the main switches 3 and 13, respectively, and supply the DC motor 4 with the power necessary to rotate the DC motor 4 at a specified speed. A high-level pulse signal with an appropriate width is given. First, when a high level pulse is applied to the base of transistor 9, transistor 9 is turned on. Then, a direct current flows from the storage battery 1 through the fuse 2, the main switch 3, the armature winding 41, the shunt resistor 5, the intermediate tap of the primary winding 61, the transistor 9, the main switch 13, and the shunt resistor 8. flows. At this time, the DC motor 4
When a field voltage is supplied to the field winding 42 of the DC motor 4, the DC motor 4 rotates. Next, a high level pulse is applied to the base of transistor 10 and a low level pulse is applied to the base of transistor 9. Then, transistor 9 is turned off and transistor 10 is turned on. For this purpose, we will use storage battery 1,
Fuse 2, main switch 3, armature winding 41, shunt resistor 5, intermediate tap of primary winding 61, transistor 10, main switch 13, shunt resistor 8
Direct current flows through the path. transistor 9
1 due to the above-mentioned transistor 9 being turned on between turning off and turning on transistor 10.
A current due to the magnetic energy stored in the secondary winding 61 flows as a freewheeling current through the rectifying diode 14, the main switch 3, the armature winding 41, the shunt resistor 5, and the primary winding 61. Similarly, when the transistor 10 is turned off, the freewheeling current flows to the diode 15 side. Note that the surge voltage generated by turning on and off the transistors 9 and 10 is charged and absorbed by the capacitor 17 via the rectifying diode 14 or 15 and the inductance 16.

Thereafter, transistor 9 or 10 is connected in the same manner.
Each time a high-level pulse is alternately applied to each base of the transistor 9 or 10, the transistor 9 or 10 is turned on and off, thereby supplying power to the armature winding 41 in proportion to the duty of the pulse signal.
By controlling the power supplied to the armature winding 41 in this way, the rotational speed of the DC motor 4, that is, the running speed of the electric vehicle is controlled.

Next, the operation when performing regeneration control will be explained. When performing regeneration control, main switches 3 and 1
This is done by deactivating transistors 9 and 10 and increasing the current in field winding 42 with transistors 9 and 10 closed. That is, during regenerative running of an electric vehicle, the induced voltage of the armature winding 41 is controlled to be higher than the voltage of the storage battery 1 by increasing the field current, and the DC motor 4 is operated as a generator. operate as The current of this power generation output flows through the main switch 3, fuse 2, storage battery 1, shunt resistor 8, switch 13, and diodes 11 and 1.
2, through the primary winding 61, the intermediate tap and the shunt resistor 5, thereby charging the storage battery 1. At this time, by turning on the thyristor 7, the diodes 11, 12 and the primary winding 6
1 may be bypassed.

Next, the storage battery 1 is
We will explain the operation when charging. When charging the storage battery 1 with an AC power source, the main switches 3 and 13 are opened and both ends of the secondary winding 62 of the transformer 6 are connected to the AC power source. When the AC power supply has the indicated polarity (this case is called a positive half cycle),
An induced voltage of the polarity shown is generated between the intermediate tap of the primary winding 61 of the transformer 6 and the terminal on the diode 14 side. This induced voltage causes a rectifier diode 14, a fuse 2, a storage battery 1, a shunt resistor 8,
A charging current flows through the path of the thyristor 7 and charges the storage battery 1. On the other hand, when the AC power supply has a polarity opposite to that shown in the figure (that is, during a negative half cycle), the intermediate tap of the primary winding 61 and the diode 15
An induced voltage is also generated between the side terminal and the intermediate tap side. This induced voltage causes a charging current to flow through the path of the rectifier diode 15, fuse 2, storage battery 1, shunt resistor 8, and thyristor 7, and charges the storage battery 1. In this way, the storage battery 1 is charged with the DC voltage obtained by full-wave rectifying the AC power source with the rectifying diodes 14 and 15.

Next, the operation in a mode in which the control circuit operates as an inverter circuit and generates an alternating current voltage will be described. In this case, the main switches 3 and 13 are closed to cut off the field voltage of the field winding 42. Then, transistors 9 and 10 are alternately connected to each other, for example.
Give a pulse with a frequency of 60Hz. First, when a pulse is applied to the base of the transistor 9, the transistor 9 becomes conductive, and an excitation current flows from the intermediate tap of the primary winding 61 of the transformer 6 to one end thereof, similar to the chopper circuit described above. At this time,
Due to the action of the transformer 6, a voltage equal to the turns ratio a×the voltage E of the storage battery 1 appears at both ends of the 2 o'clock winding 62. Next, when a low level pulse is applied to the base of the transistor 9 and a high level pulse is applied to the base of the transistor 10, the transistor 10 becomes conductive, and the connection is made between the middle tap and the other end of the primary winding 61. An excitation current flows through the transistor 10 through the transistor 10 . At this time, a voltage of -aE appears across the secondary winding 62. When transistors 9 and 10 are alternately switched in this manner, an alternating current voltage is generated in the secondary winding 62 of the transformer 6. Therefore, an AC electric device can be connected to the secondary winding 62 for use. Note that the diodes 11 and 12 function to feed back the reactive power of the load to the storage battery 1.

As described above, according to this embodiment, one control circuit is operated as a chopper circuit to control the rotation speed of the DC motor 4, and the DC motor 4 is operated as a generator during driving to perform regeneration control. It is possible to charge the storage battery 1 by applying AC power from the outside to the secondary winding 62, or to generate AC voltage from the secondary winding 62 by operating the control circuit as an inverter circuit. can.

FIG. 2 is an electrical circuit diagram of another embodiment of the invention. In the embodiment shown in FIG. 2, rectification during charging by an external power source is performed using diodes 11, 12, 14,
15, the number of turns of the primary winding 61 can be halved compared to that in FIG. 1, and the voltage obtained in the inverter mode can be doubled. In this way, 1 of transformer 6
By using a transformer in which the number of turns of the secondary winding 61 is small, when the transistors 9 and 10 are turned on and off with low frequency pulses, the excitation current increases because the inductance is small, resulting in a slight increase in loss.
Therefore, this embodiment is advantageous when the frequency of the pulses applied from the oscillation circuit to the bases of transistors 9 and 10 can be set relatively high, and the control device is smaller than the one in FIG. can get.

FIG. 3 is an electrical circuit diagram of another embodiment of the invention. In the embodiment shown in FIG. 3, contacts 231 and 23 are used instead of the main switch 3 shown in FIG.
2 and a common contact 233, the contact 232 is connected to one end of the armature winding 41, the contact 231 is connected to one end of the primary winding 61 via the thyristor 19, and the main switch 23 includes a common contact 233.
0 to the other end of the primary winding 61. Further, an inductance 21 and a capacitor 22 are connected to both ends of the primary winding 61 for turning off the thyristors 19 and 20. Further, a diode 24 is connected between the contact 232 of the main switch 23 and the common contact 233. When the control circuit operates as a chopper circuit, pulses are applied alternately to transistors 9 and 10 from the oscillation circuit, and when the control circuit operates as an inverter circuit, pulses are applied to the base of transistor 9 and the thyristor 20.
A synchronized pulse is applied to the gate of the transistor 10, and a synchronized pulse is also applied to the base of the transistor 10 and the gate of the thyristor 19.

Next, the operation of the embodiment shown in FIG. 3 will be explained. First, when driving, connect the main switch 23 to contact 2.
32 side to alternately switch transistors 9 and 10, respectively. Then, a DC current flows from the storage battery 1 through the fuse 2, the main switch 23, the armature winding 41, the shunt resistor 5, the primary winding 61, the transistor 9 or 10, and the shunt resistor 8. The supplied current is controlled intermittently. Note that the freewheeling current flows through the diodes 14 and 15.

Next, in the case of regenerative control, when the field current of the field winding 42 is increased, the voltage is increased from the armature winding 41 to the diode 24 or the switch 23, the fuse 2, the storage battery 1, the shunt resistor 8, the diode 11.
Alternatively, a direct current flows through the primary winding 61 and the shunt resistor 5, and the storage battery 1 is charged.

When charging the storage battery 1 by applying AC voltage to the secondary winding 62, the main switch 23 is switched to the contact 231 side. The alternating current voltage induced in the primary winding 61 is full-wave rectified by a bridge circuit including diodes 11, 12, 14, and 15, and a direct current voltage is applied to the storage battery 1.

Next, when operating the control circuit as an inverter circuit, with the main switch 23 switched to the contact 231 side, pulses are applied from the oscillation circuit to the gate of the thyristor 20 and the base of the transistor 9, and these pulses are alternately A pulse is applied to the gate of thyristor 19 and the base of transistor 10. That is, when a pulse is applied to the gate of the thyristor 20 and the base of the transistor 9, an excitation current flows from the storage battery 1 through the path of the thyristor 20, the primary winding 61, and the transistor 9. At this time, the capacitor 22 is charged to the illustrated polarity. Next, if a pulse is applied to the gate of thyristor 19 and the base of transistor 10 without applying a pulse to thyristor 20 and transistor 9,
Thyristor 19 and transistor 10 are turned on, a reverse voltage is applied from capacitor 22 to thyristor 20, and thyristor 20 is turned off, while an excitation current flows through primary winding 61 in the opposite direction. By repeating this operation, 2
An alternating current voltage can be extracted from the secondary winding 62.
Note that the AC voltage generated from the secondary winding 62 is 2
The next winding 62 can be freely selected by providing a suitable intermediate tap.

FIG. 4 is an electrical circuit diagram showing another embodiment of the present invention. The embodiment shown in FIG. 4 differs from the impedance 21 of the embodiment shown in FIG.
A transistor 27 is provided in place of the capacitor 22, and the contact 231 of the main switch 23 and the thyristor 1
The collector and emitter of a transistor 27 are connected between the anodes 9 and 20, respectively. And to operate it as an inverter circuit. When applying a pulse to transistor 9 and thyristor 20 or transistor 10 and thyristor 19, a pulse is also applied to the base of transistor 27. That is, when a pulse is applied to the base of transistor 9, the gate of thyristor 20, and the base of transistor 27, transistors 9 and 2
7 and thyristor 20 become conductive, and an excitation current flows through the path of storage battery 1, fuse 2, main switch 23, transistor 27, thyristor 20, primary winding 61, and transistor 9. After that, when the base pulse of the transistor 27 disappears and the transistor 27 turns off, the thyristor 20 also turns off.
Turn off. Furthermore, when a pulse is applied to the base of the transistor 10 and the base of the transistor 27, the transistors 10 and 27 and the thyristor 1
9 are conductive, respectively, storage battery 1, fuse 2, main switch 23, transistor 27, thyristor 1
9, an excitation current flows through a path between the primary winding 61 and the transistor 10. In this way, transistor 9 or 10 is turned on while transistor 27 is turned on.
An alternating current voltage can also be generated from the secondary winding 62 of the transformer 6 by turning on the transformer 6 alternately.

FIG. 5 is an electrical circuit diagram showing another embodiment of the present invention. The embodiment shown in FIG. 5 is the same as the embodiment shown in FIG. 3 above, except for the following points. That is, the thyristor 1 shown in FIG.
Transistors 25 and 26 are provided in place of transistors 9 and 20, and inductance 21 and capacitor 22 are omitted. When operating as a chopper circuit, pulses are applied alternately to the bases of transistors 9 and 10. In addition, when operating as an inverter circuit, the transistor 9
A pulse is commonly applied to the base of the transistor 10 and the base of the transistor 26, and a pulse is also commonly applied to the base of the transistor 10 and the base of the transistor 25. Therefore, when operating as an inverter circuit, the respective combinations of transistors 9 and 26 and transistors 10 and 25 are turned on alternately, so that an alternating current voltage can be generated from the secondary winding 62 of the transformer 6.

FIG. 6 is an electrical circuit diagram of another embodiment of the invention. The embodiment shown in FIG. 6 is the same as the embodiment shown in FIG. 5 described above except for the following points. That is, the primary winding 61 of the transformer 6 is divided into two to provide a first winding 611 and a second winding 612. One end of the first winding 611 is connected to the collector of the transistor 9 via the shunt resistor 33, and the other end of the first winding 611 is connected to the switch 3.
0 common contact 303. Second winding 61
One end of 2 is connected to switch 3 via shunt resistor 34.
0 contact 302, the cathode of the diode 12, the contact 311 of the switch 31, the emitter of the transistor 26, and one end of the armature winding 41. The other end of the second winding 612 is connected to the contact 3 of the switch 30.
01 and switch 31 contact 312 and diode 3
Connect to the anode of No. 2. The cathode of diode 32 is connected to one end of fuse 2 .

Next, the operation of the embodiment shown in FIG. 6 will be explained. During power running, the main switch 23 is connected to the contact point 232.
switch 30 to contact 30.
2 side and the switch 31 to the contact 312 side. Then, a common pulse is applied to the bases of transistors 9 and 10 to turn them on simultaneously. Then, storage battery 1, fuse 2, switch 2
3. Armature winding 41, contact 30 of switch 30
2,303, first winding 611, shunt resistor 3
3. Direct current flows through the transistor 9, and the storage battery 1, fuse 2, and switch 2
3. DC current flows through the armature winding 41, the shunt resistor 34, the second winding 612, the contact 301 of the switch 30, the contact 312 of the switch 31, and the transistor 10. And transistor 9
The rotational speed of the DC motor 4 can be controlled by controlling the on-periods of and 10.

Next, the operation in the case of regeneration control will be explained. When each switch 23, 30, and 31 is switched during power running, when the current flowing through the field winding 42 is increased, the current flows from the armature winding 41 to the main switch 23, the fuse 2, and the storage battery 1 to the diode 12 and the armature. Winding 41 and diode 1
2. Direct current flows through the path of the armature winding 41, and the storage battery 1 is charged.

Next, when charging the storage battery 1 using an AC power source, switch the main switch 23 to the contact 231 side, switch 30 to the contact 301 side, and switch 30 to the contact 301 side.
1 to the contact 311 side. When AC power is applied to the secondary winding 62, since the common contact 303 of the switch 30 is switched to the contact 301 side, the first winding 611 and the second winding 612
are connected in series, and a stepped-down AC voltage is generated across the primary winding 61, and this AC voltage is full-wave rectified by the diodes 11, 12, 14, and 15. Then, the rectified DC voltage is applied to the storage battery 1 via the fuse 2, and the storage battery 1 is charged.

Next, the operation as an inverter circuit will be explained. Turn each switch 23, 3 in the same way as when charging.
0 and 31 to alternately apply pulses to the bases of transistors 9 and 26 and transistors 10 and 25. Thereby, transistors 9 and 2
6 and the combination of transistors 10 and 25 alternately switch the secondary winding 62 of the transformer 6.
AC voltage can be generated from

FIG. 7 is an electrical circuit diagram of another embodiment of the invention. In the embodiment shown in FIG. 7, one end of the main switch 3 of the embodiment shown in FIG. 61, one end of the armature winding 41 is connected to the negative electrode side of the storage battery 1, and a parallel circuit of transistor 9 and diode 11 and a parallel circuit of transistor 10 and diode 12 are connected to both ends of primary winding 61. and is connected to the positive electrode side of the storage battery 1.

During power running, when pulses are applied alternately to the bases of transistors 9 and 10 with main switch 3 closed, they operate as a chopper circuit, and armature winding 41
The rotational speed of the DC motor 4 in which the current flowing through the DC motor 4 is intermittent is controlled. During regeneration control, armature winding 4
1 is applied to the storage battery 1 from the intermediate tap of the primary winding 61 through both ends of the primary winding and diodes 11 and 12, so that it can be charged. When charging the storage battery 1 with an external AC power source, when the main switch 3 is opened, the AC voltage appearing across the primary winding 61 is transferred to the diodes 11 and 1.
2, 14 and 15, and the rectified DC voltage is applied to the storage battery 1. Also,
When operating as an inverter circuit, a sinusoidal AC voltage is applied to the bases of transistors 9 and 10 with main switch 3 open. Then,
A sinusoidal voltage appears at each emitter of transistors 9 and 10, and this sinusoidal voltage is applied to both ends of the primary winding 61, so that a sinusoidal AC voltage can be generated in the secondary winding 62. can.

Effects of the Invention As described above, according to the present invention, during running, the first and second switching elements and the primary winding of the transformer operate as a chopper circuit to reduce the current flowing to the armature winding of the DC motor. The rotation speed is controlled intermittently, and when charging the storage battery, AC voltage is applied from the secondary winding of the transformer, and the AC voltage appearing in the primary winding is rectified by first and second rectifying diodes to create DC voltage. Voltage is applied to the storage battery, and when stopped, the first and second switching elements, the primary and secondary windings of the transformer, and the first and second diodes are operated as an inverter circuit, and AC is output from the secondary winding. Since voltage is generated, common electric appliances such as work lights and vacuum cleaners can be easily used in electric vehicles using this alternating current voltage.

[Brief explanation of the drawing]

FIG. 1 is an electrical circuit diagram of an embodiment of the present invention. FIG. 2 is an electrical circuit diagram of another embodiment of the invention. 3, 4, 5, 6 and 7 are electrical circuit diagrams of other embodiments of the invention. In the figure, 1 is a storage battery, 3 and 13 are main switches, 4 is a DC motor, 41 is an armature winding, 42 is a field winding, 6 is a transformer, 61 is a primary winding, 62 is a
is a secondary winding; 7, 18, 19, and 20 are thyristors; 9, 10, 25, 26, and 27 are transistors; 11, 12, 14, 15, 24, and 32 are diodes; and 30 and 31 are switches.

Claims (1)

[Claims] 1. A storage battery 1, a running DC motor 4 including an armature winding, a primary winding and a secondary winding including an intermediate tap, and the intermediate tap is connected to the armature winding. A transformer 6 is connected to the transformer 6, and an alternating current voltage is applied to the secondary winding when the storage battery is charged. Each transformer 6 is connected to both ends of the primary winding of the transformer, and operates as a chopper circuit together with the primary winding during running. The first and second switching elements 9, 10 are connected in antiparallel to the first and second switching elements, respectively, and operate as a freewheeling device when the vehicle is running, and operate as a freewheeling device when the vehicle is stopped.
first and second diodes 11 and 12 that operate as an inverter circuit together with a switching element and a primary winding and a secondary winding of the transformer, each of which is connected between both ends of the primary winding of the transformer and the storage battery. first and second rectifying diodes 14, 15 connected to the storage battery for rectifying the alternating current voltage generated in the primary winding of the transformer when charging the storage battery to charge the storage battery; An AC voltage generation circuit for an electric vehicle, comprising an oscillation means for generating an oscillation voltage for switching two switching elements, respectively, and generating an AC voltage from a secondary winding of the transformer.