Double-machine redundant water turbine speed regulating system

Abstract

The invention relates to the field of water turbine sets, and discloses a double-machine redundant water turbine speed regulating system which comprises a signal acquisition module used for acquiring set state signals and double sets of control units including a main machine and a standby machine, the double sets of control units are connected with the signal acquisition module and used for generating control signals according to the set state signals, and the main machine is connected with the standby machine. The switching control circuit is connected with the double sets of control units and used for switching the control right to the standby machine when the main machine breaks down and transmitting a control signal, the electro-hydraulic conversion and execution mechanism is connected with the switching control circuit and used for driving a water turbine guide vane to act according to the control signal, a guide vane action result forms a part of a unit state signal, and the unit state signal is transmitted to the standby machine. The signal is acquired by the signal acquisition module; by arranging the double sets of control units and the switching control circuit, a redundancy control system is formed, so that the effects of realizing undisturbed switching when the main control unit fails, eliminating a single-point fault and greatly improving the operation reliability and stability of the system are achieved.

Description

Technical Field

[0001] This invention relates to the field of hydro turbine units, and in particular to a dual-redundant hydro turbine speed control system. Background Technology

[0002] The turbine governor is the core control equipment that ensures the stable operation of the turbine generator unit. It controls the unit speed and power by adjusting the guide vane opening through an electro-hydraulic system.

[0003] Currently, this type of equipment has revealed many technical defects during long-term operation. The existing technology generally uses a single-set control system with a lack of redundancy and backup, which poses a risk of single point of failure. Once the control unit fails, it will directly lead to the loss of control of the unit and seriously affect the safety of the power station. In addition, a small number of systems have the function of switching between the main and backup control units. However, when the existing system switches between the main and backup control units or changes the operating mode, it is easy to cause a sudden change in the guide vane opening, which will generate significant disturbances and make it impossible to achieve a smooth and disturbance-free switching, affecting the stability of the power grid. These technical problems restrict the further improvement of the reliability of the turbine speed regulation system. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is that the existing turbine speed control system cannot achieve high reliability and uninterrupted stable operation due to the lack of redundancy in the control unit and the disturbance generated during the switching between main and backup.

[0005] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a dual-redundant turbine speed control system, which includes, The signal acquisition module is used to acquire unit status signals; The system includes a main unit and a standby unit, which are connected to the signal acquisition module and are used to generate control signals based on the unit status signals. A switching control circuit is connected to the dual control units, used to switch control to the backup unit when the primary unit fails, and to transmit control signals. An electro-hydraulic conversion and actuator, connected to the switching control circuit, is used to drive the turbine guide vanes to move according to the control signal; The guide vane movement results constitute part of the unit status signal and are acquired by the signal acquisition module.

[0006] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the main turbine and the standby turbine have the same hardware and software configuration and communicate data in real time to maintain state synchronization; The primary or backup unit with control authority is the current control unit, and the control signals are generated and issued by the current control unit.

[0007] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the switching control circuit is composed of a contactless relay, specifically an optically isolated relay, and the switching time is in the microsecond range.

[0008] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the unit status signals acquired by the signal acquisition module include speed signal, guide vane opening signal and grid frequency signal; The rotational speed signal is obtained in parallel through two methods: speed measurement of the gear disc and speed measurement of the residual voltage of the voltage transformer.

[0009] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention, a human-machine interface is also included. The human-machine interface is connected to the dual control units. The human-machine interface is configured to display the system operating status, set control parameters, provide fault alarm information, and support the testing and waveform recording functions of the speed controller.

[0010] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the dual control units are programmable logic controllers and are equipped with a frequency measurement module for processing the speed signal.

[0011] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the electro-hydraulic conversion and actuation mechanism includes a proportional valve as an electro-hydraulic conversion element and a hydraulic relay for driving the guide vanes.

[0012] In a preferred embodiment of the dual-redundant turbine speed control system of the present invention: the switching control circuit is configured such that when the control authority is switched from the primary turbine to the standby turbine, the resulting change in the stroke of the hydraulic relay is no greater than one percent of its total stroke.

[0013] The beneficial effects of the present invention are as follows: by setting up two sets of control units and switching control circuits, the present invention constitutes a redundant control system, thereby achieving the effects of seamless switching when the main control unit fails, eliminating single point of failure, and greatly improving the reliability and stability of system operation. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention.

[0015] Figure 1 A schematic diagram of the overall process of the present invention is shown; Figure 2 A schematic diagram illustrating the control switching of the present invention is shown. Detailed Implementation

[0016] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0017] The terminology used in this invention refers to those general terms currently widely used in the art in consideration of the functionality of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new techniques. Furthermore, specific terms may be chosen independently, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terminology used in this specification should not be construed as simple names, but rather based on the meaning of the terms and the overall description of the invention.

[0018] Reference Figure 1 and Figure 2 This embodiment provides a dual-redundant turbine speed control system, including: Signal acquisition module 4 is used to acquire unit status signals; The dual control unit 1 includes a main unit 11 and a standby unit 12. The dual control unit 1 is connected to the signal acquisition module 4, which is used to generate control signals based on the unit status signals. Switching control circuit 2 connects to dual control units 1, used to switch control to standby unit 12 when the main unit 11 fails, and to transmit control signals; The electro-hydraulic conversion and actuator 3 is connected to the switching control circuit 2 and is used to drive the turbine guide vanes to move according to the control signal. The guide vane movement results constitute part of the unit status signal, which is acquired by signal acquisition module 4; Among them, the acquisition module 4 is equipped with a displacement sensor.

[0019] During operation, the signal acquisition module 4 continuously acquires the unit status signal and sends it to the dual control unit 1. The dual control unit 1 receives the signal and performs calculations to generate corresponding control signals. The control signals are transmitted to the electro-hydraulic conversion and actuator 3 via the switching control circuit 2, thereby driving the turbine guide vanes to move. The movement of the guide vanes causes a change in their opening. This change is detected and fed back by the displacement sensor in the signal acquisition module 4, thus forming a closed-loop control circuit to ensure that the control system can correct deviations in real time and maintain stable operation.

[0020] As one embodiment provided in this application, such as Figure 1 and Figure 2 The primary machine 11 and the backup machine 12 have the same hardware and software configuration and communicate with each other in real time to keep their states synchronized. The primary unit 11 or the backup unit 12 with control authority is the current control unit, and the control signals are generated and issued by the current control unit.

[0021] The switching control circuit 2 is composed of a contactless relay, specifically an optically isolated relay.

[0022] In addition, real-time data synchronization between the primary unit 11 and the hot standby unit 12 includes synchronization of operating status, adjustment parameters and output commands, to ensure that the output control signal of the standby unit 12 and the output control signal of the primary unit 11 are continuous and without sudden changes at the moment of switching.

[0023] During normal operation, the primary unit 11 and the backup unit 12 communicate in real time and synchronize their operating status. The switching control circuit 2 continuously monitors the operating status of the primary unit 11. When a fault occurs that affects the basic operation of the primary unit 11, the switching control circuit 2 automatically and seamlessly switches to the backup unit 12.

[0024] Optically isolated relays are contactless electronic switches with switching times in the microsecond range and high isolation voltage, thereby ensuring the reliability and speed of switching.

[0025] As one embodiment provided in this application, such as Figure 1 The unit status signals acquired by the signal acquisition module 4 include speed signal, guide vane opening signal and grid frequency signal; The rotational speed signal is obtained in parallel through two methods: speed measurement of the gear disc and speed measurement of the residual voltage of the voltage transformer.

[0026] It also includes the human-computer interaction interface 5; The human-machine interface 5 is connected to the dual control units 1. The human-machine interface 5 is configured to display the system operating status, set control parameters, provide fault alarm information, and support the speed controller's testing and waveform recording functions.

[0027] The dual control unit 1 is a programmable logic controller and is equipped with a frequency measurement module for processing speed signals.

[0028] By employing two different speed measurement methods—tooth disc speed measurement and voltage transformer residual voltage speed measurement—redundancy is created, greatly improving the reliability and continuity of speed signal acquisition, thereby ensuring the stability and safety of the entire speed control system.

[0029] The human-machine interface 5 uses a touch screen display for online switching of various operating modes of the speed controller, switching of control modes, increase or decrease of setpoint, modification of parameters, and fault reset. It also has the functions of speed controller fault recording and recall, as well as various tests and test waveform recording functions of the speed controller.

[0030] The dual control unit 1 has an online fault self-diagnosis function, which can diagnose CPU module faults, power supply faults, communication module faults and speed measurement system faults, and display the faults through the human-machine interface 5. At the same time, the fault information is provided to the power station computer monitoring system through the communication interface.

[0031] As one embodiment provided in this application, such as Figure 1 and Figure 2 The electro-hydraulic conversion and actuator 3 includes a proportional valve as an electro-hydraulic conversion element and a hydraulic relay for driving the guide vane.

[0032] The switching control circuit 2 is configured such that when control is switched from the master unit 11 to the standby unit 12, the resulting change in the stroke of the hydraulic relay is no more than one percent of its full stroke.

[0033] During operation, the control signal from the switching control circuit 2 drives the proportional valve. As an electro-hydraulic conversion element, the proportional valve converts the electrical signal into a hydraulic signal, controls the direction and flow of pressurized oil into the hydraulic servo, thereby driving the piston of the servo to move, and ultimately controlling the opening of the turbine guide vanes.

[0034] The performance of this invention is ultimately quantified into a key indicator: the change in the stroke of the hydraulic relay caused when the control is switched from the primary unit 11 to the standby unit 12. This invention controls this change to be strictly limited to no more than one percent of the full stroke of the relay, so that the unit power and speed are almost without fluctuation, thereby ensuring the ability of the redundant system to guarantee the stability of the power grid in practical applications.

[0035] In summary, by setting up two sets of control units 1 and switching control circuits 2, the present invention constitutes a redundant control system, thereby achieving the effects of seamless switching when the main control unit fails, eliminating single points of failure, and significantly improving the reliability and stability of system operation.

[0036] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A dual-redundant turbine speed control system, characterized in that: include, The signal acquisition module (4) is used to acquire unit status signals; The dual control unit (1) includes a main unit (11) and a standby unit (12). The dual control unit (1) is connected to the signal acquisition module (4) and is used to generate control signals according to the unit status signal. The switching control circuit (2) is connected to the dual control unit (1) and is used to switch control to the standby unit (12) when the main unit (11) fails, and to transmit control signals. An electro-hydraulic conversion and actuator (3) is connected to the switching control circuit (2) and is used to drive the turbine guide vanes to move according to the control signal. The guide vane action results constitute part of the unit status signal and are collected by the signal acquisition module (4).

2. The dual-redundant turbine speed control system according to claim 1, characterized in that: The main machine (11) and the backup machine (12) have the same hardware and software configuration and communicate data in real time to keep their states synchronized. The primary unit (11) or the backup unit (12) with control authority is the current control unit, and the control signal is generated and issued by the current control unit.

3. The dual-redundant turbine speed control system according to claim 2, characterized in that: The switching control circuit (2) is composed of a contactless relay, specifically an optically isolated relay.

4. The dual-redundant turbine speed control system according to claim 3, characterized in that: The unit status signals acquired by the signal acquisition module (4) include speed signal, guide vane opening signal and grid frequency signal; The rotational speed signal is obtained in parallel through two methods: speed measurement of the gear disc and speed measurement of the residual voltage of the voltage transformer.

5. The dual-redundant turbine speed control system according to claim 4, characterized in that: It also includes the human-computer interaction interface (5); The human-machine interface (5) is connected to the dual control unit (1). The human-machine interface (5) is configured to display the system operating status, set control parameters, provide fault alarm information, and support the test and recording functions of the speed controller.

6. The dual-redundant turbine speed control system according to claim 4 or 5, characterized in that: The dual control unit (1) is a programmable logic controller and is equipped with a frequency measurement module for processing the rotation speed signal.

7. The dual-redundant turbine speed control system according to claim 6, characterized in that: The electro-hydraulic conversion and actuator (3) includes a proportional valve as an electro-hydraulic conversion element and a hydraulic relay for driving the guide vane.

8. The dual-redundant turbine speed control system according to claim 7, characterized in that: The switching control circuit (2) is configured such that when control is switched from the master unit (11) to the standby unit (12), the resulting change in the stroke of the hydraulic relay is no more than one percent of its full stroke.

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