JP2016092873A - Thyristor excitation system power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve responsiveness of voltage startup at a thyristor excitation system power generator.SOLUTION: A thyristor excitation system power generator includes: a power generator; an excitation transformer; an automatic voltage regulation device; an excitation device; a voltage setting unit for outputting a control signal when an output voltage of the power generator has reached a set value; a first proportional gain calculation unit for calculating a first proportional gain from a field voltage of the excitation device; a second proportional gain calculation unit for calculating a second proportional gain from a deviation between the output voltage of the power generator and a secondary voltage of the excitation transformer; an adder that obtains a deviation between a sum of the first proportional gain and the second proportional gain and the control signal; and a firing control unit for calculating a firing signal from an output of the adder and outputting the firing signal to the excitation device.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a thyristor excitation type generator, and more particularly to an improvement in response speed at startup of a thyristor excitation type generator.

  The generator generates electricity by rotating an electromagnet. Changing the strength of the electromagnet changes the output voltage of the generator. The output voltage of the generator is adjusted to match the fluctuation of electricity used in factories and the like. The thyristor excitation method is one of the methods for changing the strength of the electromagnet, and since the switch function of the thyristor that is a semiconductor element is used, the excitation current of the electromagnet can be changed at high speed (for example, Patent Documents 1 to 5). . An excitation transformer is connected to the main circuit of the generator, and the secondary output of the excitation transformer is converted into direct current by a thyristor rectifier. Excitation power is supplied to the field winding of the generator via a field breaker and a slip ring.

  In the thyristor excitation method, 70E mode for performing feedback control of the field voltage and 90R mode for performing feedback control of the output voltage are known as methods for controlling the output voltage of the generator. The thyristor excitation type automatic voltage adjustment device adopts the 70E mode when starting the generator, and adjusts the output voltage of the generator by feedback control of the field voltage. This mode format is displayed using the basic equipment number (70: R / C resistor, 90: automatic voltage regulator) and auxiliary symbols (E: excitation, R: adjustment) according to the control equipment number of JEM1090 of the Japan Electrical Manufacturers' Association. Has been.

JP 58-123400 A JP 7-245999 A Japanese Patent Laid-Open No. 4-14500 JP 7-227100 A JP-A 63-283500

  In an actual generator, environmental conditions such as the rotor temperature of the generator and the impedance of the DC power source are changing. In the thyristor excitation type automatic voltage regulator, initial excitation congestion occurs due to a slow response speed or changes in environmental conditions. If the output voltage of the generator does not rise to the target value, it will take time for the on-site adjustment test. The present invention has been made to solve such a problem, and it is intended to improve the responsiveness of the voltage startup in the thyristor excitation generator by compensating the initial forcing in the feedback control of the field voltage. It is aimed.

  A thyristor excitation generator according to the present invention includes a generator that generates a voltage when a field current flows through a field winding, and an excitation transformer that is connected to the generator and outputs a voltage to a secondary side. An automatic voltage regulator having a voltage setting unit, an adder, a firing control unit, a first proportional gain computing unit and a second proportional gain computing unit, and a thyristor whose gate is opened and closed according to a firing signal output from the automatic voltage regulating device The voltage setting unit outputs a control signal when the output voltage of the generator reaches a set value, and the first proportional gain calculation unit The first proportional gain is calculated from the field voltage of the excitation device, the second proportional gain calculation unit calculates the second proportional gain from the deviation between the output voltage of the generator and the secondary voltage of the excitation transformer, Sum of first proportional gain and second proportional gain and control signal A deviation between, ignition control unit calculates the firing signal from the output of the adder, and outputs the excitation device.

  According to the said structure, the output voltage of a thyristor excitation system generator is started by the feedback control of a field voltage. In the thyristor start-up type automatic voltage regulator, by compensating the constant field voltage control block, the response speed at start-up is improved, and the supply accuracy of excitation power is further improved.

It is a principle figure showing the system configuration of the thyristor excitation system generator concerning the present invention. It is a control block diagram which shows the automatic voltage regulator concerning Embodiment 1 of this invention. It is a figure which shows the response of the output voltage of the generator in the basic block of an automatic voltage regulator. It is a figure which shows the structure of the basic block in an automatic voltage regulator. It is a figure which shows the response of the output voltage of the generator in Embodiment 1 of this invention. It is a control block diagram which shows the automatic voltage regulator concerning Embodiment 2 of this invention. It is a figure which shows the response of the output voltage of the generator in Embodiment 2 of this invention. It is a control block diagram which shows the automatic voltage regulator concerning Embodiment 3 of this invention. It is a figure which shows the response of the output voltage of the generator in Embodiment 3 of this invention.

  A thyristor excitation type generator and an automatic voltage regulator according to an embodiment of the present invention will be described below with reference to the drawings. In each figure, the same or similar components are denoted by the same reference numerals, and the sizes and scales of the corresponding components are independent. For example, when the same components that are not changed are illustrated in cross-sectional views in which a part of the configuration is changed, the sizes and scales of the same components may be different. In addition, the configuration of the thyristor excitation type generator and the automatic voltage regulator is actually provided with a plurality of members, but for the sake of simplicity, only the parts necessary for the description are described, and the other parts are described. Is omitted.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 shows a system configuration of a thyristor excitation type generator 100. An excitation transformer 5 is connected to the generator 1. The field winding 2 of the generator 1 is connected to the initial excitation circuit 3 and the excitation device 9 via a slip ring 20 (brush-collector ring). When the generator 1 is started, a field current is passed through the field winding 2. When power generation is performed by the field current, an output voltage is generated in the generator 1. A stepped down voltage is generated on the secondary side of the excitation transformer 5. The field breaker 3 a is installed between the initial excitation circuit 3 and the field winding 2. The field breaker 4 a is installed between the excitation device 9 and the field winding 2. The secondary voltage (Vac) of the excitation transformer, the output voltage (Vg) of the generator, the field voltage (V1) of the excitation device, and the like are input to the automatic voltage regulator 30 (AVR: Automatic Voltage Regulator).

  The thyristor 4 of the exciter 9 opens and closes according to the ignition signal output from the automatic voltage regulator 30. The system control device 40 is related to the system control of the thyristor excitation type generator 100 and controls the initial excitation circuit 3, the automatic voltage adjustment device 30, and the like. When the generator 1 is started, a field current is supplied to the field winding 2. If the output voltage (V0) of the initial excitation circuit is larger than the field voltage (V1) of the excitation device, a field current is supplied from the initial excitation circuit 3 to the field winding 2. If the output voltage (V0) of the initial excitation circuit is smaller than the field voltage (V1) of the excitation device, the field current is supplied from the excitation device 9 (thyristor 4) to the field winding 2.

  FIG. 2 shows a control block diagram of the automatic voltage regulator 30. The automatic voltage adjustment device 30 according to the present embodiment includes a voltage setting unit 6, an adder 7a, an adder 7b, an ignition control unit 8, a gain calculation unit 10, a proportional gain calculation unit 13, and the like. When the output voltage (Vg) of the generator reaches the first set value, the voltage setting unit 6 outputs a control signal (70E) to the adder 7a. The adder 7a receives outputs from the voltage setting unit 6 (70E: excitation adjusting resistor), the gain calculation unit 10 (first proportional gain calculation unit), and the proportional gain calculation unit 13 (second proportional gain calculation unit). ing. The output of the adder 7a is input to the ignition control unit 8. The ignition signal generated by the ignition control unit 8 is input to the excitation device 9 to control the opening / closing degree of the thyristor 4. The output voltage 11 (Vg) of the generator and the secondary voltage 12 (Vac) of the exciting transformer are input to the adder 7b. The output of the adder 7 b is input to the proportional gain calculation unit 13.

  That is, the adder 7a obtains the deviation between the sum of the first proportional gain output from the gain calculation unit 10 and the second proportional gain output from the proportional gain calculation unit 13 and the control signal (70E). The gain calculation unit 10 calculates a proportional gain (first proportional gain) from the field voltage (V1) of the excitation device. The proportional gain calculation unit 13 calculates a proportional gain (second proportional gain) from the deviation between the output voltage 11 (Vg) of the generator and the secondary voltage 12 (Vac) of the excitation transformer. The output of the exciter 9 is input to the generator 1 and is also input to the gain calculator 10 for feeding back the field voltage. The field voltage (V1) of the exciter is fed back, the deviation from the set value of the voltage setting unit 6 is calculated, and the field current of the exciter 9 is controlled.

  Next, the operation at the time of initial excitation of the automatic voltage regulator 30 will be described. First, the voltage response at start-up in the basic control block of the automatic voltage regulator 30 will be described with reference to FIG. As shown in FIG. 4, the basic control block includes a voltage setting unit 6, an adder 7a, an ignition control unit 8, a gain calculation unit 10, and the like. The automatic voltage adjustment device 30 feeds back the field voltage of the excitation device 9 to the ignition control unit 8 and controls the field current of the excitation device 9 with the ignition pulse. The adder 7a calculates a deviation between the set value of the voltage setting unit 6 and the field voltage of the excitation device 9, and the ignition control unit 8 calculates an ignition signal from this deviation. Since the output voltage (V 0) of the initial excitation circuit is higher than the field voltage (V 1) of the exciter at the start-up, the field current is supplied from the initial excitation circuit 3 to the field winding 2. When the field breaker 4a is turned on, the initial excitation circuit 3 is turned on, and a field current corresponding to about 15% of the initial value (target value) of 70E is supplied from the initial excitation circuit 3 to the field winding 2.

  At the same time, the initial excitation congestion timer starts counting in the automatic voltage regulator 30. When the output voltage (Vg) of the generator reaches about 10% (first set value) of the target value, the voltage setting unit 6 starts to operate, and the output voltage (Vg) of the generator increases. When detecting that the output voltage (Vg) of the generator is 0.6 p.u. (second set value) or more, the system control device 40 turns off the initial excitation circuit 3 and resets the initial excitation congestion timer. If the output voltage (Vg) of the generator does not reach 0.6 p.u. within the default value of the initial excitation congestion timer, an initial excitation congestion occurs. The timer value is normally set to 30 seconds. In the control by the basic control block, when the generator is started, the output voltage (Vg) of the generator is almost 0, and the output of the excitation device 9 is small, so the response of the start voltage is slow.

  Next, the role of the proportional gain calculation unit 13 will be described. FIG. 5 shows a voltage response when the generator according to the present embodiment is started. The adder 7b of the automatic voltage regulator 30 outputs a deviation between the output voltage (Vg) of the generator and the secondary voltage (Vac) of the exciting transformer. The proportional gain calculation unit 13 calculates a proportional gain from this deviation. The proportional gain output from the proportional gain calculator 13 is input to the adder 7a. In the automatic voltage regulator 30, the voltage setting unit 6 performs control in the 70E mode, and outputs a predetermined set value. When the output voltage (Vg) of the generator reaches about 10% (first set value) of the target value, the voltage setting unit 6 starts to operate, and the output voltage (Vg) of the generator increases. When detecting that the output voltage (Vg) of the generator is 0.6 p.u. (second set value) or more, the system control device 40 turns off the initial excitation circuit 3 and resets the initial excitation congestion timer. The field voltage (V1) of the exciter is fed back to the adder 7a, the deviation from the set value of 70E is calculated, and the field current of the exciter 9 is controlled by the firing pulse.

  According to the thyristor excitation generator according to the present embodiment, a proportional gain proportional to the deviation between the output voltage (Vg) of the generator and the secondary voltage (Vac) of the excitation transformer is added. Can greatly compensate for the output of the exciter. That is, initial forcing is performed by adding a proportional gain corresponding to the deviation between the output voltage (Vg) of the generator and the secondary voltage (Vac) of the excitation transformer to the basic control block of the 70E mode. Improves voltage response at startup. As a result, the output voltage (Vg) of the generator is almost 0 at the time of startup, and the output of the exciter is small, but the response of the startup voltage is fast.

Embodiment 2. FIG.
Since the resistance of the generator rotor (and the field winding 2) changes due to a change in ambient temperature, the magnitude of the field current also changes in the excitation device 9 when the environmental temperature changes. As a result, a deviation occurs between the output voltage (Vg) of the generator and the target value (70E initial value). The automatic voltage regulator according to the second embodiment adds an integral gain proportional to the deviation between the design temperature of the field winding and the measured temperature of the field winding to the basic control block, so that the voltage at the start-up of the generator To compensate for deviations. FIG. 6 shows a control block diagram of the automatic voltage regulator 30 according to the present embodiment. The measured temperature 15 of the field winding and the design temperature 16 of the field winding are input to the adder 7c, and the integral gain calculator 14 outputs the integral gain from the difference between the two. The integral gain is input to the adder 7a. That is, the adder 7a obtains the deviation between the sum of the proportional gain output from the gain calculation unit 10 and the integration gain output from the integral gain calculation unit 14 and the control signal (70E).

  Next, the operation of the present embodiment will be described. FIG. 7 shows the voltage response when the generator according to this embodiment is started. When the resistance of the field winding 2 changes due to a change in the ambient temperature, the field current changes in the excitation device 9, and a deviation occurs between the output voltage (Vg) of the generator and the target value (70E initial value). According to the present invention, the deviation of the generator output voltage (Vg) is controlled to be zero by compensating the integral gain corresponding to the deviation between the design temperature of the field winding and the measured temperature of the field winding. . As a result, it is not necessary to restart each time the setting value of the voltage setting unit is changed. Further, the adjustment time at the site is not required, and the deviation of the output voltage (Vg) response of the generator is improved.

Embodiment 3 FIG.
FIG. 8 is a control block diagram of the automatic voltage regulator according to the third embodiment. The automatic voltage regulator 30 according to the present embodiment is a combination of the control block of the first embodiment and the control block of the second embodiment. The output voltage 11 of the generator and the secondary voltage 12 of the excitation transformer are input to the adder 7b, and the proportional gain calculation unit 13 calculates a proportional gain (second proportional gain) from the difference between the two. The measured temperature 15 of the field winding and the design temperature 16 of the field winding are input to the adder 7c, and the integral gain calculation unit 14 calculates the integral gain from the difference between the two. The proportional gain output from the proportional gain calculator 13 and the integral gain output from the integral gain calculator 14 are input to the adder 7d. The output of the adder 7d is input to the adder 7a. That is, the adder 7a and the adder 7d include a proportional gain (first proportional gain) output from the gain calculating unit 10, a proportional gain (second proportional gain) output from the proportional gain calculating unit 13, and an integral gain calculating unit 14, respectively. The deviation between the sum of output integral gains and the control signal (70E) is obtained.

  Next, the operation of the present embodiment will be described. FIG. 9 shows the voltage response when the generator according to this embodiment is started. According to the present embodiment, a proportional gain proportional to the deviation between the generator output voltage (Vg) and the excitation transformer secondary voltage (Vac) is added to the basic control block. Voltage responsiveness can be improved. Further, by adding an integral gain proportional to the deviation between the design temperature of the field winding and the measured temperature of the field winding, the deviation of the output voltage of the generator can be compensated to zero.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  1 generator, 2 field winding, 3 initial excitation circuit, 3a field breaker, 4 thyristor, 4a field breaker, 5 excitation transformer, 6 voltage setting unit, 7a adder, 7b adder, 7c addition 7d adder 8 firing control unit 9 excitation device 10 gain computation unit 11 generator output voltage 12 excitation transformer secondary voltage 13 proportional gain computation unit 14 integral gain computation unit 15 Measurement temperature of field winding, 16 Design temperature of field winding, 20 Slip ring, 30 Automatic voltage regulator, 40 system controller, 100 Thyristor excitation generator

Claims (3)

A generator that generates a voltage when a field current flows through the field winding;
An excitation transformer connected to the generator and outputting a voltage to the secondary side;
An automatic voltage regulator having a voltage setting unit, an adder, an ignition control unit, a first proportional gain calculation unit, and a second proportional gain calculation unit;
An excitation device having a thyristor whose gate opens and closes in accordance with an ignition signal output from the automatic voltage regulator, and supplies a field current to the field winding;
The voltage setting unit outputs a control signal when the output voltage of the generator reaches a set value,
The first proportional gain calculation unit calculates a first proportional gain from a field voltage of the exciter,
The second proportional gain calculator calculates a second proportional gain from the deviation between the output voltage of the generator and the secondary voltage of the excitation transformer,
The adder obtains a deviation between the control signal and the sum of the first proportional gain and the second proportional gain,
The ignition control unit calculates the ignition signal from the output of the adder and outputs the calculated ignition signal to the excitation device. A generator that generates a voltage when a field current flows through the field winding;
An excitation transformer connected to the generator and outputting a voltage to the secondary side;
An automatic voltage regulator having a voltage setting unit, an adder, an ignition control unit, a gain calculation unit, and an integral gain calculation unit;
An excitation device having a thyristor whose gate opens and closes in accordance with an ignition signal output from the automatic voltage regulator, and supplies a field current to the field winding;
The voltage setting unit outputs a control signal when the output voltage of the generator reaches a set value,
The gain calculator calculates a proportional gain from the field voltage of the exciter,
The integral gain calculation unit calculates an integral gain from a deviation between a temperature design value of the field winding and a temperature measurement value of the field winding,
The adder obtains a deviation between the control signal and the sum of the proportional gain and the integral gain,
The ignition control unit calculates the ignition signal from the output of the adder and outputs the calculated ignition signal to the excitation device. A generator that generates a voltage when a field current flows through the field winding;
An excitation transformer connected to the generator and outputting a voltage to the secondary side;
An automatic voltage regulator having a voltage setting unit, an adder, an ignition control unit, a first proportional gain calculation unit, a second proportional gain calculation unit, and an integral gain calculation unit;
An excitation device having a thyristor whose gate opens and closes in accordance with an ignition signal output from the automatic voltage regulator, and supplies a field current to the field winding;
The voltage setting unit outputs a control signal when the output voltage of the generator reaches a set value,
The first proportional gain calculation unit calculates a first proportional gain from a field voltage of the exciter,
The second proportional gain calculator calculates a second proportional gain from the deviation between the output voltage of the generator and the secondary voltage of the excitation transformer,
The integral gain calculation unit calculates an integral gain from a deviation between a temperature design value of the field winding and a temperature measurement value of the field winding,
The adder calculates a deviation between the control signal and the sum of the first proportional gain, the second proportional gain and the integral gain;
The ignition control unit calculates the ignition signal from the output of the adder and outputs the calculated ignition signal to the excitation device.

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