CN215932890U - Practical training device for water turbine speed regulator - Google Patents

Practical training device for water turbine speed regulator Download PDF

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Publication number
CN215932890U
CN215932890U CN202121202703.4U CN202121202703U CN215932890U CN 215932890 U CN215932890 U CN 215932890U CN 202121202703 U CN202121202703 U CN 202121202703U CN 215932890 U CN215932890 U CN 215932890U
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China
Prior art keywords
speed regulator
valve
oil
servomotor
oil pressure
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Expired - Fee Related
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CN202121202703.4U
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Chinese (zh)
Inventor
曾云军
岳建锋
罗志明
赵新朝
曲岩
李江
闫明
樊锦
冷天先
文磊
荣红
陈阳
陈一鸣
陈明艳
钟新元
吴永智
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nari Technology Co Ltd
Huaneng Lancang River Hydropower Co Ltd
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Nari Technology Co Ltd
Huaneng Lancang River Hydropower Co Ltd
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Priority to CN202121202703.4U priority Critical patent/CN215932890U/en
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Publication of CN215932890U publication Critical patent/CN215932890U/en
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Abstract

The utility model provides a practical training device for a water turbine speed regulator, which comprises a speed regulator electrical control system, a speed regulator mechanical hydraulic system and a hydroelectric generating set simulation device, wherein the speed regulator electrical control system comprises a speed regulator control circuit, a speed regulator mechanical hydraulic system and a hydroelectric generating set simulation device; the speed regulator electrical control system is connected with the speed regulator mechanical hydraulic system, the speed regulator system is composed of an oil pressure device, an oil pressure device control unit, a servomotor position feedback device, an overspeed limiter, an accident pressure distributing valve, a subsection closing device and a water guide mechanism, the oil pressure device control unit is connected with the oil pressure device, the oil pressure device is connected with the servomotor, and the servomotor position feedback device are in signal connection with the water turbine generator set simulation device and the speed regulator electrical control system respectively. The utility model is convenient for operation and maintenance personnel to carry out professional skill training and simulate fault treatment, thereby really achieving the purposes of training the professional personnel and improving the professional skill.

Description

Practical training device for water turbine speed regulator
Technical Field
The utility model relates to the technical field of speed governor fault diagnosis practical training devices, in particular to a practical training device for a water turbine speed governor.
Background
The governor of the hydraulic turbine is a very important auxiliary control device of the hydroelectric generating set, and is one of the frequent devices of accidents, faults and defects of the hydroelectric generating set, and the safe and stable operation of the hydroelectric generating set is directly influenced by the quality of the operation of the governor. In order to ensure the reliable operation of the water turbine governor, the capability of the practitioner in analyzing and judging the accidents and the faults of the water turbine governor must be improved, preventive measures can be taken in time, and the defect handling capability is enhanced. However, in actual work, it is difficult to have an opportunity to learn the accidents, faults and defects of the hydraulic turbine governor system comprehensively, and there is no opportunity to perform actual drilling of running, overhauling, installing and debugging of the hydraulic turbine governor on actual equipment, or actual operation, which affects the improvement of professional skills of practitioners.
In order to improve professional skills of practitioners of the hydraulic turbine governor and enhance the analysis and processing capacity of equipment accidents, faults and defects, a practical training device for the hydraulic turbine governor is urgently needed.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a water turbine speed regulator device practical training device integrating an electrical control system of a water turbine speed regulator, a mechanical hydraulic system of the speed regulator, a servomotor and a water distributor into a whole, which can simulate the running condition of the water turbine speed regulator, can be used for teaching the maintenance and installation actual operation of the water turbine speed regulator, can also be used for debugging and experimental demonstration of the water turbine speed regulator, and can be used for carrying out actual operation training on the device by staff.
The embodiment of the utility model is realized by the following technical scheme: the utility model provides a real device of instructing for hydraulic turbine speed regulator, includes speed regulator electrical control system and speed regulator machinery hydraulic system, still includes: the system comprises a hydroelectric generating set simulation device and a monitoring control center used for controlling an electrical control system of the speed regulator through a switching value, wherein the monitoring control center is in signal connection with an upper computer;
the speed regulator electric control system is connected with a speed regulator mechanical hydraulic system, the speed regulator system consists of an oil pressure device, an oil pressure device control unit, a servomotor position feedback device, an overspeed limiter, an accident pressure distributing valve, a subsection closing device and a water guide mechanism, wherein the oil pressure device control unit is connected with the oil pressure device, the oil pressure device is connected with the servomotor, the servomotor is connected with a water-turbine generator set simulation device, and the servomotor position feedback device is in signal connection with the speed regulator electric control system;
therefore, the oil pressure device control unit comprises an oil filter, the output end of the oil filter is respectively connected with the accident pressure distribution valve, the subsection closing device and the overspeed limiter, the subsection closing device is connected between the accident pressure distribution valve and the servomotor, and the servomotor is connected to the water distributor.
According to a preferred embodiment, the oil pressure device control unit further comprises a main pressure distribution valve, a reversing valve, a servo proportional valve and an emergency stop solenoid valve;
the oil pressure device comprises an oil return tank, and the oil return tank is respectively connected with the main pressure distribution valve, the accident pressure distribution valve and the oil filter through a reversing valve;
the speed regulator electric control system is connected with the servomotor through the servo proportional valve.
According to a preferred embodiment, two servo proportional valves and two emergency stop solenoid valves are provided.
According to a preferred embodiment, the oil pressure device is connected with an oil pump, a safety valve, an oil hose, an accumulator and an unloading valve.
According to a preferred embodiment, the safety valve adopts a direct-acting overflow valve and is arranged at the outlet of the oil pump.
According to a preferred embodiment, the main distributing valve is a horizontally-mounted main distributing valve with the diameter DN 50.
According to a preferred embodiment, the emergency distribution valve is a cartridge valve type, and is provided with a function of mechanical overspeed and electrical overspeed actions and an emergency distribution valve of an interface electromagnetic valve.
According to a preferred embodiment, the section closing device is of the slide valve type, with time adjustment and inflection point modification.
The technical scheme of the embodiment of the utility model at least has the following advantages and beneficial effects: the simulation device is compact in structural arrangement of all components, convenient to install, provided with the high-performance hydroelectric generating set simulation device, capable of performing routine tests such as start-up and shut-down, load carrying and load shedding of the unit according to national standards, and also capable of performing various grid-related tests such as primary frequency modulation and power closed loop, and is convenient for operation and maintenance personnel to perform professional skill training such as speed regulator equipment operation, daily maintenance defect elimination and maintenance, dynamic/static tests and the like, and simulating fault treatment. The hydraulic power station water turbine speed regulator is designed according to the actual function of the hydraulic power station water turbine speed regulator, is tightly attached to actual equipment, and really achieves the purposes of training professionals and improving professional skills.
Drawings
Fig. 1 is a schematic structural diagram of a practical training device provided in embodiment 1 of the present invention;
fig. 2 is a schematic block diagram of a practical training device provided in embodiment 1 of the present invention;
icon: 100-oil pressure device control unit, 200-servomotor, 300-accident pressure distributing valve, 400-sectional closing device, 500-energy accumulator, 600-oil return tank, 700-water guide mechanism, and 800-oil pressure device.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Example 1
Referring to fig. 1, fig. 1 is a schematic structural diagram illustrating a practical training device for a hydro governor according to an embodiment of the present invention.
The embodiment of the utility model provides a practical training device for a hydraulic turbine speed regulator, which comprises a speed regulator electrical control system and a speed regulator mechanical hydraulic system, and further comprises: the hydraulic generator set simulation device and the monitoring control center are used for controlling the speed regulator electrical control system through the switching value, and the monitoring control center is in signal connection with an upper computer.
Further, the speed governor mechanical hydraulic system of the present embodiment is described below, in which the speed governor electrical control system is connected to the speed governor mechanical hydraulic system, and the speed governor system is composed of an oil pressure device 800, an oil pressure device control unit 100, a relay 200, a relay position feedback device, an overspeed limiter, an emergency pressure distribution valve 300, a section closing device 400, and a water guide 700.
The hydraulic device control unit 100 is connected with the hydraulic device 800, the hydraulic device 800 is connected with the servomotor 200, the servomotor 200 is connected with the water-turbine generator set simulation device, and the servomotor position feedback device is in signal connection with the speed regulator electrical control system. And two sections of slopes are arranged by sectional closing, the first section is mainly used for inhibiting the rotation speed from rising, and the second section is used for reducing the water pressure rising rate of the pressure steel pipe and weakening the tail water hammer effect.
The oil hydraulic device control unit 100 includes an oil filter, the output end of which is connected to the emergency relief valve 300, the sectionalizing closing means 400, and the overspeed limiter, respectively, the sectionalizing closing means 400 being connected between the emergency relief valve 300 and the relay 200, the relay 200 being connected to the water guide 700.
Further, the oil pressure device control unit 100 further includes a main pressure distribution valve, a reversing valve, a servo proportional valve, and an emergency stop solenoid valve; the oil pressure device 800 comprises an oil return tank 600, and the oil return tank 600 is respectively connected with a main pressure distribution valve, an accident pressure distribution valve 300 and an oil filter through reversing valves; the speed regulator electric control system is connected with the servomotor 200 through the servo proportional valve. The oil return tank 600 is used for storing hydraulic oil and serves as an installation body of the governor according to the embodiment of the present invention.
Furthermore, the servo proportional valve and the emergency stop electromagnetic valve are both provided with two valves, and the functions of automatic, manual and emergency stop can be realized by matching with 1 reversing valve.
Further, the oil pressure device 800 is connected to an oil pump, a safety valve, an oil hose, an accumulator 500, and an unloading valve. In this embodiment, a three-phase asynchronous motor is used to drive the oil pump. The oil pump adopts a high-pressure gear pump, and has small volume, high efficiency and flexible installation. The safety valve adopts a direct-acting overflow valve with an adjusting handle and is arranged at the outlet of the oil pump. The function of the oil pump is that when the system oil pressure is higher than the rated oil pressure and the oil pump is still working, the safety valve is opened to discharge the pressure oil output by the oil pump into the oil return tank 600 directly. The prepressing quantity of the spring in the regulating valve can adjust the opening pressure value. The accumulator 500 adopts a bag type accumulator 500, the bag type accumulator 500 is a pressure container with oil and gas isolation, and a bag in a steel cylinder is pre-filled with nitrogen. When the oil pump delivers hydraulic oil into the accumulator 500, the volume of gas in the bladder decreases as the pressure increases, thereby storing energy. Typically, the oil-to-gas ratio within accumulator 500 is 1: 1.
in the embodiment of the utility model, the oil pump further comprises an oil suction port oil filter which is arranged on the oil suction port of the oil pump and is used for blocking flocculent and granular mechanical impurities so as to protect the oil pump. The high-precision oil filter is arranged on a pressure pipeline, adopts an inlet glass fiber filter material, has the characteristics of high filtering precision, strong oil passing capacity and the like, and is convenient to disassemble. The oil filter is installed on a pressure pipeline and used for further blocking impurities and improving the cleanliness of pressure oil, so that the normal and reliable work of a system is ensured. Further, the accumulator 500 oil drain valve is further included, so that when the accumulator 500 fails, the oil drain valve is opened, the pressure oil in the accumulator 500 is put into the oil return tank 600, and the accumulator 500 can be repaired or replaced. The oil pump further comprises a pressure transmitter and a pressure switch, wherein when the oil pressure is reduced or increased to a setting value, the contact is closed, a signal is sent to the oil pump motor control cabinet, and the oil pump is started or closed. The pressure gauge is German WIKA.
Further, the main pressure distribution valve of the embodiment adopts a horizontally-mounted main pressure distribution valve with the drift diameter of DN 50.
Further, the emergency pressure distribution valve 300 of the present embodiment is a cartridge valve type, and the emergency pressure distribution valve 300 has a function of mechanical overspeed and electrical overspeed operations and an interface solenoid valve.
Further, the section closing device 400 of the present embodiment adopts a slide valve type, and the section closing device 400 has a time adjustment and inflection point modification function.
Referring to fig. 2, fig. 2 is a schematic block diagram of a practical training device according to an embodiment of the present invention.
The monitoring control center controls an electric control system of the speed regulator through switching values (instructions such as starting, stopping, increasing and decreasing and the like), the electric control system of the speed regulator outputs an electric signal, the servomotor 200, namely the guide vane servomotor 200, is controlled (provided with an electric amplification plate) through a proportional servo valve, and the servomotor position feedback device respectively sends collected displacement information of the guide vane servomotor 200 to the electric control system of the speed regulator and the simulation device of the water-turbine generator set; the water-turbine generator set simulation device outputs a generator set rotating speed signal to the speed regulator electrical control system.
When the circuit breakers of the water turbine generator set simulation device are separated, the simulation device converts a guide vane opening signal into a generator set frequency and outputs the generator set frequency to an electric regulator, and the electric regulator carries out no-load regulation; when the position of the circuit breaker is closed, the simulation device simulates power generation, the electric speed regulator carries out power generation regulation, the electric control system of the speed regulator sends a unit active power signal input by the simulation device to the monitoring control center, and the monitoring control center receives the signal, so that power closed-loop regulation can be realized on the simulation device. It should be noted that, according to the practical training device, when a primary frequency modulation command is input, the speed regulator can perform a primary frequency modulation test; when the active closed-loop instruction is put into use, the speed regulator can perform a power closed-loop test, wherein a power set value is received by an MODBUS protocol through a serial port. The speed regulator electrical control system is connected with a frequency signal generator.
Further, the following describes the electric control system of the governor of the present embodiment, which employs an electric adjusting device of a SAFR-2000H series hydro governor. The device comprises a dual power supply module, a frequency measurement signal processing module, a redundantly configured X20 PCC controller, a touch screen and the like, wherein a novel X20 PCC controller adopts a modular plug structure and comprises a CPU module, a power module, an input module, an output module, a frequency measurement module, a time synchronization module and a communication module.
The PU module is responsible for controlling the whole process and finishing unit regulation calculation and control output; the high-speed counting module of the communication modules such as Ethernet communication, man-machine interface communication and the like completes the simulation measurement of the frequency of the unit and the power grid; the analog quantity input module is used for measuring the stroke of the guide vane servomotor 200, the unit power and the water head, and the analog output module is used for controlling and outputting the 2-path electro-hydraulic converter; the switching value input module can collect external switching value commands of starting, stopping, generating, increasing, reducing and the like; the switching value output module can output state signals such as manual frequency modulation and primary frequency modulation and some fault signals. The frequency measurement signal and the power signal are simulated through the hydroelectric generating set simulation device, and other signals are subjected to real-time feedback and switching value tia artificial intervention to realize closed-loop regulation of the system.
It should be noted that, in the A, B dual-computer redundancy switching system formed by the above modules, all PCC modules are configured redundantly, which can ensure the information redundancy between two regulators and the stable operation during the mutual switching. The two regulators have independent power supplies and independent feedback sampling channels. Two sets of CPUs respectively process the acquired signals, one set is in a master control mode, and the other set is in a hot standby mode. When one set of the intelligent switching units fails or needs to be overhauled, the other set of the intelligent switching units is immediately put into operation. Master-slave switching between two sets of PCC is controlled by an intelligent switching device, and the intelligent switching device selects ZeN programmable PLC of Onglong company. When the PCC of the host fails and the other PCC of the host works normally, the PLC can automatically switch the PCC which works normally to the host. A human-computer interface of the electric control system of the speed regulator adopts a 15-inch high-brightness liquid crystal touch display screen of B & R company. As a monitoring display and operation interface of the whole control system of the speed regulator, the touch screen and the PCC controller have the same software development platform, the touch screen and the PCC controller are communicated without programming, the compatibility is good, the sampling speed is high, the memory is large, the real-time performance is good, the real-time communication and the real-time wave recording can be realized, and the like.
The embodiment of the utility model also provides a practical training method for the hydro governor, which is applied to the practical training device and comprises the following steps:
s1, connecting a monitoring control center with an upper computer in a communication manner;
s2, carrying out operation of setting faults;
s3, inputting a signal to an electrical control system of the speed regulator through a monitoring control center to control the speed regulator to be started;
s4, inputting a primary frequency modulation instruction or a power closed loop instruction;
s5, controlling the circuit breaker of the water turbine generator set simulation device to open and close, and carrying out no-load adjustment or realizing power closed-loop adjustment;
and S6, implementing feedback and monitoring of information such as alarm, fault and state of the speed regulator through the upper computer. In conclusion, the simulation device for the high-performance hydroelectric generating set is compact in structural arrangement and convenient to install, is provided with the high-performance hydroelectric generating set simulation device, can be used for carrying out conventional tests such as start-up and shut-down, load carrying and load shedding of the hydroelectric generating set according to national standards, can also be used for carrying out various networking tests such as primary frequency modulation and power closed loop, is convenient for operation and maintenance personnel to carry out professional skill training such as speed regulator equipment operation, daily maintenance defect elimination and maintenance, dynamic/static tests and the like, and can be used for simulating fault treatment. The hydraulic power station water turbine speed regulator is designed according to the actual function of the hydraulic power station water turbine speed regulator, is tightly attached to actual equipment, and really achieves the purposes of training professionals and improving professional skills.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. The utility model provides a real device of instructing for hydraulic turbine speed regulator, includes speed regulator electrical control system and speed regulator machinery hydraulic system, its characterized in that still includes: the system comprises a hydroelectric generating set simulation device and a monitoring control center used for controlling an electrical control system of the speed regulator through a switching value, wherein the monitoring control center is in signal connection with an upper computer;
the speed regulator electric control system is connected with a speed regulator mechanical hydraulic system, the speed regulator system consists of an oil pressure device (800), an oil pressure device control unit (100), a servomotor (200) position feedback device, an overspeed limiter, an accident pressure distributing valve (300), a sectional closing device (400) and a water guide mechanism (700), wherein the oil pressure device control unit (100) is connected with the oil pressure device (800), the oil pressure device (800) is connected with the servomotor (200), the servomotor (200) is connected with a water turbine generator set simulation device, and the servomotor (200) position feedback device is in signal connection with the speed regulator electric control system;
therefore, the oil pressure device control unit (100) comprises an oil filter, the output end of the oil filter is respectively connected with the accident pressure distributing valve (300), the subsection closing device (400) and the overspeed limiter, the subsection closing device (400) is connected between the accident pressure distributing valve (300) and the servomotor (200), and the servomotor (200) is connected to the water distributor (700).
2. The practical training device for hydro turbine governor according to claim 1, characterized in that the hydro plant control unit (100) further comprises a main distributing valve, a reversing valve, a servo proportional valve, and an emergency stop solenoid valve;
the oil pressure device (800) comprises an oil return tank (600), and the oil return tank (600) is respectively connected with a main pressure distribution valve, an accident pressure distribution valve (300) and an oil filter through a reversing valve;
the speed regulator electric control system is connected with the servomotor (200) through the servo proportional valve.
3. The practical training device for the hydro governor according to claim 2, wherein there are two servo proportional valves and two emergency stop solenoid valves.
4. The practical training device for the hydro governor according to claim 3, wherein the oil pressure device (800) is connected with an oil pump, a relief valve, an oil hose, an accumulator (500), and an unloading valve.
5. The practical training device for the hydro governor according to claim 4, wherein the relief valve is a direct-acting relief valve and is installed at an outlet of the oil pump.
6. The practical training device for the hydro governor according to claim 5, wherein the main distributing valve is a horizontally mounted main distributing valve with a drift diameter of DN 50.
7. The practical training device for the hydro governor according to claim 6, wherein the emergency distributing valve (300) is a cartridge valve type emergency distributing valve (300) with mechanical and electrical overspeed action function and interface solenoid valve.
8. The practical training device for a hydro governor according to claim 7, wherein the sectionalizing closing device (400) employs a slide valve type sectionalizing closing device (400) with time adjustment and inflection point modification functions.
CN202121202703.4U 2021-06-01 2021-06-01 Practical training device for water turbine speed regulator Expired - Fee Related CN215932890U (en)

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Application Number Priority Date Filing Date Title
CN202121202703.4U CN215932890U (en) 2021-06-01 2021-06-01 Practical training device for water turbine speed regulator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202121202703.4U CN215932890U (en) 2021-06-01 2021-06-01 Practical training device for water turbine speed regulator

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Publication Number Publication Date
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115938185A (en) * 2023-02-03 2023-04-07 华能济南黄台发电有限公司 State overhaul training device for EH control system of power plant

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115938185A (en) * 2023-02-03 2023-04-07 华能济南黄台发电有限公司 State overhaul training device for EH control system of power plant
CN115938185B (en) * 2023-02-03 2023-07-25 华能济南黄台发电有限公司 Power plant EH control system state overhauls training set

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Granted publication date: 20220301