CN219499250U - Turbogenerator excitation system - Google Patents

Abstract

The utility model discloses a turbo generator excitation system, which comprises a generator, an excitation transformer, an excitation regulator, a rectifying unit and a de-excitation unit, wherein the output end of the generator is connected with the input end of the excitation transformer, the output end of the excitation transformer is respectively connected with the input ends of the rectifying unit and the excitation regulator, one line of the output end of the excitation regulator is connected with the rectifying unit, the other line is supplied to a factory power supply, the output end of the rectifying unit is connected with the de-excitation unit, the de-excitation unit is connected with a generator rotor, and a synchronous transformer is arranged between the excitation transformer and the excitation regulator. The utility model monitors the performance parameters of the excitation regulator in real time through the monitoring system, if faults occur, the excitation regulator can be timely regulated.

Description

Turbogenerator excitation system

Technical Field

The utility model relates to the technical field of excitation systems, in particular to a steam turbine generator excitation system.

Background

The excitation system is an important component of the generator and is used for providing adjustable excitation current for the generator so as to meet the requirements of normal power generation of the generator and safe operation of a power system. Therefore, the excitation of the generator is regulated and controlled, so that the running reliability, safety and stability of the generator and the power system can be ensured, and the technical and economic indexes of the generator and the power system can be improved. And part of the power grid puts higher requirements on the excitation system of the small-capacity unit in the system due to the requirement on the higher stability level of the power grid. If the multi-target control requires more efficient calculation performance of the excitation controller; the rapid control requires that the control performance of the excitation controller is more real-time and accurate; the automation of the power plant information requires the communication performance of the microcomputer excitation controller to be more convenient and quicker; meanwhile, users also put more strict requirements on cost control of manufacturer products.

The control function of the existing excitation system is single, a better control effect cannot be achieved, meanwhile, due to the complexity of the excitation system, the whole system fails, whether an excitation regulator, an excitation transformer or a rectifying unit is problematic cannot be detected timely, or when the excitation current is required to be stopped due to the fact that the generator fails, if the excitation current in operation is directly cut off, high voltage is generated at two ends of an excitation winding, insulation of the winding is broken, even a switch contact is possibly burnt out, and therefore the risk of the excitation system failure is increased.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provide the excitation system of the steam turbine generator, which has the advantages of simple structure and high reliability and reduces the risk of faults of the excitation system.

The aim of the utility model is realized by the following technical scheme:

the utility model provides a turbo generator excitation system, includes generator, excitation transformer, excitation regulator, rectifier unit and field-eliminating unit, the output of generator is connected with excitation transformer's input, and excitation transformer's output is connected with rectifier unit and excitation regulator's input respectively, and excitation regulator's output one line is connected with rectifier unit, another line is in the power supply connection of factory, rectifier unit's output with the field-eliminating unit is connected, and the field-eliminating unit is connected with the generator rotor, still is equipped with synchronous transformer between excitation transformer and the excitation regulator.

In the above summary of the utility model, further, the excitation system of the turbo generator is a double-excitation system, including excitation regulator a and excitation regulator B, the rectifying unit includes a rectifying bridge a and a rectifying bridge B, the excitation regulator a and the excitation regulator B are electrically connected through a CAN interface, the excitation regulator a and the excitation regulator B are connected with the rectifying bridge a, and the excitation regulator a and the excitation regulator B are connected with the rectifying bridge B.

In the above summary, further, alarm fuses are disposed in the rectifier bridge a and the rectifier bridge B.

In the above summary, further, the excitation regulator a and the excitation regulator B are connected to the monitoring system through MODBUS interfaces.

In the above summary, further, the output end of the generator provides stator current and stator voltage to the excitation regulator a and the excitation regulator B through wires, and voltage transformers and current transformers for measuring line voltage, current and power are arranged on the wires.

In the above summary, the de-excitation unit further includes an MK normally open contact, an MK normally closed contact, a de-excitation resistor, a voltage limiting protector, a plurality of transducers, and a de-excitation switch, where the MK normally open contact and the MK normally closed contact are arranged in parallel, and the voltage limiting protector, the plurality of transducers, and the de-excitation switch are connected in series with the MK normally open contact.

In the above summary, further, an output end of the rectifying unit is connected to a downstream end of the magnetic extinction switch.

The beneficial effects of the utility model are as follows:

in order to improve the reliability of the excitation system, the utility model is provided with the de-excitation unit, when the generator is in fault and the excitation current is required to be cut off rapidly, the de-excitation unit can absorb the magnetic field energy generated by the excitation winding, so as to slow down the change speed of the current and achieve the purpose of rapid de-excitation, thereby avoiding the expansion of accidents; and secondly, the utility model monitors the performance parameters of the excitation regulator in real time through a monitoring system, if faults occur, the excitation regulator can be timely regulated, and voltage and current transformers are arranged at a plurality of nodes of the excitation regulating system, so that the voltage, the current and the power of a circuit are monitored in real time, and problems can be timely found and maintained through the data of the voltage, the current and the power.

Drawings

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

in the figure, the power generator comprises a 1-generator, a 2-excitation transformer, a 3-excitation regulator, a 31-excitation regulator A, a 32-excitation regulator B, a 4-rectifying unit, a 41-rectifying bridge A, a 42-rectifying bridge B, a 5-demagnetizing unit, a 51-MK normally closed contact, a 52-MK normally open contact, a 53-voltage limiting protector, a 54-transmitter, a 55-demagnetizing switch, a 6-synchronous transformer, a 7-factory power supply, an 8-monitoring system and a 9-alarm type fuse.

Detailed Description

Other advantages and effects of the present utility model will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present utility model with reference to specific examples. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict.

Examples:

in the description of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or element in question must be provided with a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Referring to fig. 1, a turbo generator excitation system includes a generator 1, an excitation transformer 2, an excitation regulator 3, a rectifying unit 4 and a de-excitation unit 5, wherein an output end of the generator 1 is connected with an input end of the excitation transformer 2, an output end of the excitation transformer 2 is respectively connected with the rectifying unit 4 and an input end of the excitation regulator 3, an output end of the excitation regulator 3 is connected with the rectifying unit 4 in a line manner and is connected with a factory power supply 7 in another line manner, the factory power supply 7 here comprises a power supply unit for supplying Alternating Current (AC)/Direct Current (DC) power to the excitation controller, an output end of the rectifying unit 4 is connected with the de-excitation unit 5, the de-excitation unit 5 is connected with a rotor of the generator 1, and further exciting current is supplied to the rotor of the generator 1, and a synchronous transformer 6 is further arranged between the excitation transformer 2 and the excitation regulator 3. Specifically, the exciting transformer 2 supplies exciting power to the exciting system through the output terminal of the generator 1, but since the voltage of the output terminal of the generator 1 is high and the voltage of the input terminal of the exciting system is low, it is necessary to reduce the voltage output from the generator 1 to the input voltage of the thyristor through the exciting transformer 2.

In the foregoing embodiment, preferably, the turbo generator excitation system is a dual excitation system, including an excitation regulator a31 and an excitation regulator B32, the rectifying unit 4 includes a rectifying bridge a41 and a rectifying bridge B42, the excitation regulator a31 and the excitation regulator B32 are electrically connected through a CAN interface, the excitation regulator a31 and the excitation regulator B32 are connected with the rectifying bridge a41, and the excitation regulator a31 and the excitation regulator B32 are connected with the rectifying bridge B42. Specifically, when the excitation system works, the system can be in a single-machine working mode or a double-machine working mode. If the excitation system is a single machine, the excitation regulator A31 is used as a main component, the excitation regulator B32 is used as a standby component, and the excitation regulator A31 is monitored through the monitoring system 8, at the moment, the rectifier bridge A41 is used as the main component, the rectifier bridge B42 is used as the standby component, and when the excitation regulator A31 serving as the main component fails, the system is switched to the excitation regulator B32 through a CAN interface to work; if excitation regulator B32 fails, operation of excitation regulator a31 is switched to be performed similarly.

Alarm fuses 9 are arranged in the rectifier bridge A41 and the rectifier bridge B42. Specifically, the rectifier bridge comprises a single-phase full-control rectifier bridge formed by four thyristors and an alarm fuse 9, and is used for rectifying an alternating current power supply from a rectifier switch into a direct current power supply, connecting the direct current power supply to the rectifier unit 4 according to a pulse signal output from the excitation regulator 3, triggering the thyristors in the rectifier unit 4, and regulating the output direct current according to the change of a trigger signal of the thyristors. The rectifier bridge is provided with an alarm type fuse 9 for overcurrent protection, and when the alarm type fuse 9 is fused, a signal generator sends out a signal for realizing overvoltage protection of the rectifier bridge. The output of the rectifier bridge is connected to the rotor of the generator 1, providing the generator 1 with excitation current.

In the above embodiment, the excitation regulator a31 and the excitation regulator B32 are preferably connected to the monitoring system 8 through a MODBUS (MODBUS is a serial communication protocol, which has become an industry standard of industrial communication protocols, and is now a common connection manner between industrial electronic devices). Specifically, the monitoring system 8 is mainly connected to the DSC control cabinet and is used for monitoring excitation parameters of the excitation regulator a31 and the excitation regulator B32 during operation, so that whether the excitation regulator a31 and the excitation regulator B32 have faults or not can be rapidly found, and timely maintenance is facilitated.

The output end of the generator 1 provides stator current and stator voltage for the excitation regulator A31 and the excitation regulator B32 through wires, and voltage transformers and current transformers for measuring line voltage, current and power are arranged on the wires. Specifically, after receiving the current and voltage signals, the excitation regulator a31 and the excitation regulator B32 transform and isolate the current and voltage signals to enable the excitation regulator 3 to provide a working power supply, and then, according to different operation conditions, four paths of silicon controlled trigger signals are output to four silicon controlled rectifiers of a rectifier bridge in the excitation regulator a31 and the excitation regulator B32, so that the excitation current (voltage) is regulated.

The de-excitation unit 5 comprises an MK normally-open contact 52, an MK normally-closed contact 51, a de-excitation resistor, a voltage limiting protector 53, a plurality of transducers 54 and a de-excitation switch 55, wherein the MK normally-open contact 52 and the MK normally-closed contact 51 are arranged in parallel, the voltage limiting protector 53, the plurality of transducers 54 and the de-excitation switch 55 are connected with the MK normally-open contact 52 in series, and the output end of the rectifying unit 4 is connected with the downstream end of the de-excitation switch 55. Specifically, the magnetic deactivation switch 55 is used to switch on and off the exciting current of the main circuit of the exciting system in a loaded state. When the generator 1 fails, and when the excitation current needs to be rapidly cut off due to the failure of the generator 1, the field energy generated by the excitation winding can be absorbed by the field-eliminating unit 5, so that the change speed of the current is slowed down, and the purpose of rapid demagnetization is achieved. And the de-excitation resistor is used for consuming the residual electromagnetic energy of the rotor coil and the exciter coil of the generator 1 when the excitation system is switched from the power generation excitation operation state to the de-excitation switch 55 to be opened. The transmitters 54 can sense process parameters and transmit the measured values in a particular signal form for display and adjustment, with one of the plurality of transmitters 54 acting as a primary working machine and the remaining transmitters 54 acting as backup machines. The voltage limiting protector 53 is used for placing the voltage at the two ends of the generator to be too high.

The foregoing examples merely illustrate specific embodiments of the utility model, which are described in greater detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model.

Claims (7)

1. The utility model provides a turbo generator excitation system, its characterized in that, including generator (1), excitation transformer (2), excitation regulator (3), rectifier unit (4) and field-eliminating unit (5), the output of generator (1) is connected with the input of excitation transformer (2), and the output of excitation transformer (2) is connected with the input of rectifier unit (4) and excitation regulator (3) respectively, and the output of excitation regulator (3) is connected with rectifier unit (4) one circuit, and another circuit is connected with power supply (7) for the plant, and the output of rectifier unit (4) with field-eliminating unit (5) are connected, and field-eliminating unit (5) are connected with generator (1) rotor, still are equipped with synchronous transformer (6) between excitation transformer (2) and excitation regulator (3).

2. The excitation system of the turbo generator according to claim 1, wherein the excitation system of the turbo generator (1) is a double-machine excitation system, the double-machine excitation system comprises an excitation regulator A (31) and an excitation regulator B (32), the rectification unit (4) comprises a rectification bridge A (41) and a rectification bridge B (42), the excitation regulator A (31) and the excitation regulator B (32) are electrically connected through a CAN interface, the excitation regulator A (31) and the excitation regulator B (32) are connected with the rectification bridge A (41), and the excitation regulator A (31) and the excitation regulator B (32) are connected with the rectification bridge B (42).

3. A turbo generator excitation system according to claim 2, characterized in that alarm fuses (9) are arranged in the rectifier bridge a (41) and the rectifier bridge B (42).

4. A turbo generator excitation system according to claim 2, characterized in that excitation regulator a (31) and excitation regulator B (32) are connected to the monitoring system (8) via a MODBUS interface.

5. A turbo generator excitation system according to claim 2, characterized in that the output of the generator (1) provides stator current and stator voltage to excitation regulator a (31) and excitation regulator B (32) via wires provided with voltage and current transformers for measuring line voltage, current and power.

6. The excitation system of the turbo generator according to claim 1, wherein the de-excitation unit (5) comprises an MK normally-open contact (52), an MK normally-closed contact (51), a de-excitation resistor, a voltage limiting protector (53), a plurality of transducers (54) and a de-excitation switch (55), the MK normally-open contact (52) is arranged in parallel with the MK normally-closed contact (51), and the voltage limiting protector (53), the plurality of transducers (54) and the de-excitation switch (55) are connected in series with the MK normally-open contact (52).

7. A turbo generator excitation system according to claim 6, characterized in that the output of the rectifying unit (4) is connected to the downstream end of a magnetic extinction switch (55).