JPH0783624B2 - Rotating electric machine starting device and starting method thereof - Google Patents

Description

The present invention relates to a starting device for a rotating electric machine and a starting method thereof.

[Conventional technology]

Conventionally, as a method for starting a synchronous motor, the Electric Cooperative Research Vol. 30 No. 1 issued by the Japan Electric Cooperative Research Group on July 10, 1974
The thyristor starting method described on pages 14 to 16 of the issue is well known as a pumping starting method for large capacity synchronous generators for pumped storage power plants.

A variable speed pumped storage power generation system using an AC excitation synchronous power generator is described in JP-A-61-170300.

That is, FIG. 5 shows a conventional example of a starter of a variable speed pumped storage hydropower system using an AC excitation synchronous power generator. As shown in the figure, the variable speed pumped storage power generation system is an AC excitation synchronous generator / generator 1, a pump turbine 2, and an exciter connected to the rotor winding of the AC excitation synchronous generator / generator 1 for excitation. Power supply, for example, cycloconverter 3, control of pump turbine governor 2a and gate control of cycloconverter 3 based on information such as active power command, head or head, system voltage, rotation speed, slip phase, etc. For detecting the difference between the voltage frequency of the electric power system 5 and the rotational frequency obtained by the product of the number of magnetic pole pairs and the rotational speed of the AC excitation synchronous generator / motor 1, for example, a slip phase detector. It is composed of 6.

Further, a power source for starting, for example, a thyristor starting device is a thyristor converter including a converter and an inverter.
7, Gate control of the thyristor converter 7 by the ignition signal from the distributor 8, the distributor 8 which detects the position of the magnetic pole of the AC excitation synchronous generator / motor 1, or the terminal voltage of the AC excitation synchronous generator / motor 1. It is composed of a starting control device 9 for performing.

In the figure, 10 is a first circuit breaker, 11 is a second circuit breaker, and 12 is a speed detector.

[Problems to be Solved by the Invention]

When starting with the above device, it is necessary to excite in the stopped state, but since the slip phase detector is in the stopped state, the slip is 1.0 and the same frequency as the power system voltage frequency (50 or 60 Hz) Is output.

The control device controls the gate of the cycloconverter so that an exciting current with the same frequency as the slip frequency detected by the slip phase detector is passed, so the rotor winding of the AC excitation synchronous generator is the same as the voltage frequency of the power system. Frequency current flows. Since the AC excitation synchronous generator is stopped, a voltage having the same frequency as the voltage frequency of the power system is induced in the stator winding. In this state, the thyristor converter which is about to start at a low frequency and the AC excitation synchronous generator-motor cannot synchronize with each other and cannot be started. Therefore, generally, the stator winding of the AC excitation synchronous generator-generator 1 does not start. One side was short-circuited, AC power was applied to the rotor side, and the rotor was started as an induction motor.

However, in this starting method, the AC excitation synchronous generator-motor 1 is operated synchronously to operate as a synchronous machine when it reaches a predetermined speed. In the case where the rotational speed was reduced to a speed lower than the synchronous speed during the synchronous insertion into 5, the synchronous insertion was sometimes difficult.

The present invention has been made in view of the above, and it is an object of the present invention that the AC excitation synchronous power generator is easily started, and even if the AC excitation synchronous generator is synchronized with the power system. It is an object of the present invention to provide a starting device and a starting method for a rotary electric machine of this kind, which can be easily put in synchronously even if the rotational speed is reduced to a rotational speed lower than the synchronous speed during input.

[Means for Solving the Problems]

That is, the present invention, in the output circuit of the slip phase frequency detection device used to determine the frequency of the excitation power supply,
An oscillator that can output a voltage with an arbitrarily settable frequency is provided, and the output signal of this oscillator is output to the controller of the excitation power supply at the time of starting the rotating electric machine, and the rotating electric machine has a predetermined rotation speed. In this case, a switching switch for switching the output of the slip phase frequency detecting device to the output of the exciting power source control device is provided to achieve the intended purpose.

[Action]

That is, with the starter formed in this way, even if the AC excitation synchronous generator-motor is decelerated during synchronous insertion into the power system and the rotation speed becomes lower than the synchronous speed, the output of the slip phase frequency detection device Since it is excited by, the stator voltage of the AC-excited synchronous generator-motor is always in agreement with the voltage frequency of the electric power system, and synchronization can be easily incorporated.

〔Example〕

Hereinafter, the present invention will be described based on the illustrated embodiments. FIG. 1 shows an embodiment of the present invention. Since the same parts as those of the prior art are designated by the same reference numerals, the description thereof will be omitted. In this embodiment, a first switching switch 13a is provided between the control device 4 and the slip phase detector 6, and this first switching switch 1a is provided.
An oscillator capable of outputting a voltage of a desired frequency, such as an excitation pattern generator 14, is provided between the control device 4 and the control device 3a in parallel with the control device 4a. At the start of starting the AC excitation synchronous generator / motor 1, the first switching switch 13a and the first circuit breaker 10 are opened, and the second switching switch 13b and the second circuit breaker 11 are closed to generate an excitation pattern generator. DC voltage is generated at 14.

Due to the generation of the DC voltage in the excitation pattern generator 14, the control device 4 controls the cycloconverter 3 so that the DC current flows.
Since the gate control is performed, the AC excitation synchronous generator / motor 1 is excited by the DC current, and the thyristor converter 7 can start the thyristor like the normal synchronous generator / generator. In this way, the starting control device 9 that controls the gate of the thyristor converter 7 can start the thyristor of the AC excitation synchronous power generator 1 by the same control as the thyristor start control of the synchronous power generator.

After this start-up, the operation shifts to the normal operation, and the procedure for closing and opening the changeover switch and the circuit breaker when transitioning to the normal operation is shown in FIG. This procedure will be described with reference to FIG. In the state shown in FIG. 1, acceleration is performed in the state of direct current excitation based on the direct current signal of the excitation pattern generator 14, and the slip phase frequency also decreases when approaching the synchronous speed,
At the synchronous speed, the output of the slip phase detector 6 is also DC.
In this state, the first switching switch 13a is turned on and the second switching switch 13b is released. At this time, excitation pattern generator 1
The output of 4 and the output of the slip phase detector 6 are direct current, and when viewed from the control device 4, there is no change in the input signal,
Switching from the excitation pattern generator 14 to the slip phase detector 6 can be performed smoothly. After that, the output of the thyristor converter 7 is stopped and the second circuit breaker 11 is released, and at the same time, the first circuit breaker 10 is turned on to enter the power system 5 in parallel and the normal pumping operation is performed. The state during this normal operation is shown in FIG. As shown in the figure, in the normal operation, the first switching switch 13a and the first circuit breaker 10 are closed, and the second switching switch 13b and the second circuit breaker 11 are released. By doing so, even if the output of the thyristor converter 7 is stopped and the rotational speed is lower than the synchronous speed by decelerating while the AC excitation synchronous generator-motor 1 is inserted into the power system 5, the slip phase detection is performed. Since it is excited by the output of the electric machine 6, the stator voltage of the AC excitation synchronous generator / motor 1 always matches the voltage frequency of the electric power system 5, and synchronous insertion is possible.

As described above, according to this embodiment, since DC excitation is performed in the initial stage of starting, the thyristor start control can be performed in the same manner as the start of a normal synchronous generator-motor, and at the time of synchronous insertion, excitation based on the slip phase is performed. Since the control is performed, it is possible to surely perform the synchronization and the simultaneous insertion.

FIG. 4 shows changes in frequency and rotation speed with time when the output frequency of the excitation pattern is changed in the course of starting in another embodiment of the present invention. As shown in the figure, the output of the excitation pattern generator is set to DC in the initial stage of starting, and is continuously changed from DC to 5 Hz in the course of starting.
At this time, the frequency of the stator voltage of the AC excitation synchronous generator is also 5 Hz higher than the rotation frequency. Acceleration is performed in this state, and when the frequency of the stator voltage coincides with the voltage frequency of the electric power system, the synchronous insertion becomes possible based on the procedure shown in FIG. At this time, the actual rotation speed may be lower than the synchronous speed by 5 Hz, so when the rotational speed is accelerated to the synchronous speed, it will be synchronized with the power system in a shorter time than the broken line in the figure as shown by the solid line. You will be able to join together. That is, it is possible to shorten the time until the synchronization is included as compared with the above case.

In the above embodiment, the stator winding of the AC excitation synchronous generator is connected to the starting thyristor converter and the rotor winding is connected to the exciting cycloconverter, but the stator winding is connected to the cycloconverter. It is possible to obtain the same effect by connecting and exciting and connecting a thyristor converter for starting to the rotor winding.

Further, in the above embodiments, the thyristor converter is used as the power supply for starting, but this may be any power supply device whose output frequency can be controlled and which has a capacity necessary and sufficient for starting.
Typical examples include transistor inverters, GTO inverters, and synchronous generators.

Furthermore, in the above embodiment, an example in which a slip phase detector that detects slip by mechanical rotation is adopted has been described.
This may be a slip phase detector that derives a slip signal by analog or digital processing.

〔The invention's effect〕

As described above, according to the present invention, it is of course possible to easily start the AC excitation synchronous generator, and even if the AC excitation synchronous generator is decelerated and synchronized during synchronous insertion into the power system. Even if the rotation speed becomes lower than the rotation speed, it is possible to easily perform the synchronous insertion.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a starting state of an embodiment of a rotating electric machine starting device of the present invention, FIG. 2 is a block diagram diagram of the same embodiment at the time of synchronous insertion, and FIG. FIG. 4 is an explanatory view showing a state during normal operation of the embodiment, and FIG. 4 is a frequency when the output frequency of the excitation pattern generator of another embodiment of the rotating electric machine starting device of the present invention is changed during starting,
FIG. 5 is a characteristic diagram showing the relationship between rotation speed and time, and FIG. 5 is an explanatory diagram showing a conventional starting device for a rotary electric machine. 1 ... AC excitation synchronous power generator (rotating electric machine), 3 ... Cycloconverter (excitation power supply), 4 ... Control device,
5 ... Power system, 6 ... Slip phase detector (device for detecting slip phase frequency), 7 ... Thyristor converter (power supply for starting), 10 ... First breaker, 11 ... Second Circuit breaker, 13a ... first switching switch, 13b ... second switching switch, 14 ... excitation pattern generator (oscillator).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiro Yasaka 3-1-1, Saiwaicho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi factory (72) Inventor Hiroto Nakagawa 3 Nakanoshima, Kita-ku, Osaka-shi, Osaka 3-22 No. 22 Kansai Electric Power Co., Inc. (56) Reference JP-A-62-77885 (JP, A) JP-A-61-170300 (JP, A)

Claims (5)

[Claims] 1. A starting power source, which is connected to a stator winding of a rotating electric machine having multi-phase windings on a stator and a rotor, and includes a device for frequency-converting electric power of a power system, and the starting power source. And a controller for controlling the frequency of the starting power supply, a controller for controlling the output frequency of the device, and an exciting power supply connected to the rotor winding of the rotating electric machine and for converting the frequency. And provided in the excitation power supply,
A control device that controls the output frequency of the excitation power supply, and a slip phase frequency detection device that detects a slip phase frequency corresponding to the difference between the frequency of the power system and the rotation frequency of the rotating electric machine, and the slip phase frequency detection In a starting device for a rotating electric machine, which controls the frequency of the excitation power source so that the frequency is the same as the slip phase frequency detected by the device, a slip used to determine the frequency of the excitation power source. An oscillator capable of outputting a voltage having an arbitrarily settable frequency to the output circuit of the phase frequency detection device, and an output signal of the oscillator is output to the control device of the excitation power supply when the rotating electric machine is started, and A switching switch for switching the output of the slip phase frequency detection device to the control device of the excitation power supply when the rotating electric machine reaches a predetermined rotation speed. A starting device for a rotating electric machine, characterized in that the switch is provided. 2. A device for converting the frequency of the starting power source,
The starting device for a rotary electric machine according to claim 1, which is one of a thyristor converter, a transistor inverter, a GTO inverter, and a synchronous generator. 3. The starting device for a rotating electric machine according to claim 1, wherein the device for converting the frequency of the excitation power supply is a cycloconverter. 4. A device for detecting the slip phase frequency,
The starting device for a rotary electric machine according to claim 1, which is a slip phase detector. 5. A starting power source, which is connected to a stator winding of a rotating electric machine having a stator and a rotor having multi-phase windings, and includes a device for frequency-converting electric power of a power system, and the starting power source. A controller for controlling the output frequency of a device for converting the frequency of the starting power supply, an excitation power supply system connected to the rotor winding of the rotating electric machine, and an excitation power supply provided for the excitation power supply. A control device that controls the output frequency of the power supply, and a device that detects a slip phase frequency corresponding to the difference between the frequency of the power system and the rotation frequency of the rotating electric machine, and a detection value of the device that detects the slip phase frequency. In the method for starting a rotating electric machine that controls the control device for the excitation power supply based on the above, in the starting power supply, an oscillator capable of outputting a voltage having a desired frequency is provided, and the oscillator is At startup In the control of the control device for the excitation power supply, the output of the slip phase frequency detection device is used for control of the control device when the rotating electric machine reaches a predetermined rotation speed. How to start.