Regulating stage pressure measuring point fault prevention system

Abstract

The utility model discloses a regulating-stage pressure measuring point fault prevention system, which is characterized in that: by optimizing logic, when a regulating-stage pressure measuring point fails, regulating-stage pressure after electric load conversion is selected in main steam flow arithmetic logic to replace the regulating-stage pressure to participate in logical arithmetic logic, and a button is added after electric load conversion, so that the failure of the regulating-stage pressure measuring point is prevented. When a regulating stage pressure measuring point has a fault, regulating stage pressure after electric load conversion is automatically selected to participate in feed-forward logic, regulating stage pressure fault conditions in water supply automation and boiler main control logic are shielded, and unit load sudden change jump automation is selected. According to the scheme, after the main steam flow logic is optimized and electrical load conversion is added, button related logic is input, it can be guaranteed that when a regulating stage pressure measuring point breaks down, unit water supply automation and CCS coordination control are normally input, and safe operation of a unit is guaranteed.

Description

Technical Field

[0001] The utility model relates to the field of steam turbine failure, in particular to a system for preventing regulation stage pressure measuring point failure. Background Art

[0002] In modern thermal power plants, the distributed control system (DCS) of the unit plays a crucial role, particularly in the monitoring and control of regulating stage pressure measurement points. These pressure measurement points not only contribute to the calculation of main steam flow but are also crucial for the automatic feedwater control of the unit and the activation logic of the CCS (Centralized Control System) coordinated control. These measurement points provide real-time data, enabling the control system to make precise adjustments based on the actual operating conditions of the boiler and turbine, maintaining efficient and stable operation of the unit.

[0003] Failure of a regulating-stage pressure measurement point directly impacts the accurate calculation of main steam flow, further impacting the activation logic of the automatic feedwater control and CCS coordinated control. Since these control systems rely on accurate pressure data to adjust boiler firing rates and turbine throttles in response to grid load fluctuations and maintain stable main steam pressure, any inaccurate data could lead to control errors. This not only reduces the unit's response speed and regulation quality, but also may cause abnormal fluctuations in main steam pressure, increasing operational risks. Failure of these measurement points could result in the failure of high-pressure main steam pressure control, compromising turbine startup and safe operation.

[0004] Therefore, in order to ensure the safety and efficiency of the unit, the regulating stage pressure measuring points must be regularly maintained and calibrated to ensure their reliability and accuracy. At the same time, a corresponding backup system is also required so that when a measuring point fails, it can be quickly switched to reduce the impact on the unit operation. Utility Model Content

[0005] The purpose of the utility model is to provide a system for preventing regulating stage pressure measuring point failure, which can select the regulating stage pressure after electric load conversion in the main steam flow calculation logic to replace the regulating stage pressure in the logic calculation logic, and when the regulating stage pressure measuring point fails, the regulating stage pressure after electric load conversion is automatically selected to participate in the feedforward logic.

[0006] In order to achieve the above-mentioned purpose, the present invention is implemented through the following technical solutions.

[0007] A system for preventing regulation-stage pressure measurement point failures, comprising a converted pressure circuit and a switching circuit, wherein the converted pressure circuit comprises a broken line function module HSCHARC and a first selection module SEL, and the switching circuit comprises a second selection module SEL;

[0008] The input terminal I1 of the broken line function module HSCHARC is connected to the actual load value signal of the unit, and the output terminal AV outputs the steam pressure value signal after the regulating stage after the electric load is converted;

[0009] The first input end of the first selection module SEL is connected to the regulation stage pressure quality bad signal, the second input end is connected to the steam pressure value signal after the generator side regulation stage, and the third input end is connected to the steam pressure value signal after the regulation stage after the electric load conversion;

[0010] The first input end of the second selection module SEL is connected to the input button after the electric load is converted, the second input end is connected to the output end of the first selection module SEL, the third input end is connected to the steam pressure value signal after the regulating stage after the electric load is converted, and the output end outputs the steam pressure value after the steam turbine regulating stage.

[0011] Furthermore, in the main steam flow operation logic circuit, the steam pressure value signal after the regulating stage after the electric load conversion is used to replace the steam pressure value signal after the machine side regulating stage, and the output end of the second selection module SEL is connected to the input end of the main steam flow operation logic circuit.

[0012] Furthermore, a third selection module SEL is added to the feedforward logic circuit, the first input end of the third selection module SEL is connected to the input button after the electric load is converted, the second input end is connected to the steam pressure value signal after the machine side regulation stage, the third input end is connected to the steam pressure value signal after the regulation stage after the electric load is converted, and the output end is connected to the input end of the feedforward logic circuit.

[0013] Furthermore, it also includes a pressure fault condition circuit, which includes a signal quality check module DQ and a fourth selection module SEL. The input terminal IN of the signal quality check module DQ is connected to the actual load value signal of the unit, and the output RLA terminal is connected to the third input terminal of the fourth selection module SEL. The first input terminal of the fourth selection module SEL is connected to the electric load conversion input button, and the second input terminal is connected to the regulation stage pressure quality bad signal.

[0014] Furthermore, the pressure fault condition circuit is added to the small steam turbine feed water logic circuit and the boiler main control logic circuit.

[0015] The advantages of the present utility model are: by optimizing the logic, when the regulating stage pressure measuring point fails, the regulating stage pressure after electric load conversion is selected in the main steam flow calculation logic, instead of the regulating stage pressure participating in the logic calculation logic, and an electric load conversion input button is added. When the regulating stage pressure measuring point fails, the regulating stage pressure after electric load conversion is automatically selected to participate in the feedforward logic, and at the same time, the regulating stage pressure failure conditions in the water supply automatic and boiler main control logic are shielded, and the unit load sudden change jump is selected automatically.

[0016] This solution optimizes the main steam flow logic and adds related logic for the button after electrical load conversion, which can ensure that the unit water supply is automatically put into operation and CCS coordinated control is normally put into operation when the regulating stage pressure measuring point fails, thereby ensuring the safe operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is the main steam flow calculation logic circuit diagram of the prior art;

[0018] Figure 2 It is a feedforward logic circuit diagram of the prior art;

[0019] Figure 3 This is a logic circuit diagram of a small steam turbine water supply in the prior art;

[0020] Figure 4 This is a boiler main control logic circuit diagram of the prior art;

[0021] Figure 5 This is a new type of system for preventing regulation level pressure measurement point failures;

[0022] Figure 6 This is the improved main steam flow calculation logic circuit diagram of the utility model;

[0023] Figure 7 This is the improved feedforward logic circuit diagram of the utility model;

[0024] Figure 8 This is the improved logic circuit diagram of small steam turbine water supply in this utility model;

[0025] Figure 9 This is the improved boiler main control logic circuit diagram of the utility model. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] This embodiment discloses a system for preventing regulation level pressure measurement point failure, including a pressure conversion circuit, a switching input circuit, and a pressure failure condition circuit. Figure 1 The converted pressure circuit includes a broken line function module HSCHARC and a first selection module SEL. The input end I1 of the broken line function module HSCHARC is connected to the actual load value signal of the unit, and the output end AV outputs the steam pressure value signal after the regulating stage after the electric load is converted. The first input end of the first selection module SEL is connected to the regulating stage pressure quality bad signal, the second input end is connected to the steam pressure value signal after the regulating stage on the machine side, and the third input end is connected to the steam pressure value signal after the regulating stage after the electric load is converted.

[0028] The switching circuit includes a second selection module SEL, the first input end of the second selection module SEL is connected to the input button after the electric load is converted, the second input end is connected to the output end of the first selection module SEL, the third input end is connected to the steam pressure value signal after the regulating stage after the electric load is converted, and the output end outputs the steam pressure value after the steam turbine regulating stage.

[0029] Please refer to Figure 1 and Figure 6 In the main steam flow arithmetic logic circuit, the steam pressure value signal after the regulating stage on the turbine side is replaced by the steam pressure value signal after the regulating stage after the electric load is converted. In the prior art, the steam pressure value signal after the regulating stage on the turbine side is connected to the input ends of two multipliers MUL as an input signal. After the improvement of this solution, the steam pressure value after the regulating stage of the steam turbine at the output end of the second selection module SEL is connected to the input ends of the two multipliers MUL of the main steam flow arithmetic logic circuit.

[0030] Please refer to Figure 2 and Figure 7 A third selection module SEL is added to the feedforward logic circuit. The first input end of the third selection module SEL is connected to the input button after the electric load is converted, the second input end is connected to the steam pressure value signal after the machine side regulating stage, the third input end is connected to the steam pressure value signal after the regulating stage after the electric load is converted, and the output end is connected to the input end of the feedforward logic circuit.

[0031] Please refer to Figure 3 、 Figure 8 、 Figure 9 The pressure fault condition circuit includes a signal quality check module DQ and a fourth selection module SEL. The input terminal IN of the signal quality check module DQ is connected to the actual load value signal of the unit, and the output terminal RLA is connected to the third input terminal of the fourth selection module SEL. The first input terminal of the fourth selection module SEL is connected to the electric load conversion start-up button, and the second input terminal is connected to the regulation stage pressure quality bad signal.

[0032] The pressure fault condition circuit is added to the small steam turbine feed water logic circuit and the boiler master control logic circuit, replacing the original regulating stage pressure quality bad signal of the existing technology, as one input of the logic and module. The other inputs of the logic and module of the two logic circuits are the RUNBACK signal and the steam turbine master control automatic mode signal.

[0033] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A system for preventing regulation level pressure measurement point failure, characterized in that: It includes a converted pressure circuit and a switching input circuit, wherein the converted pressure circuit includes a broken line function module HSCHARC and a first selection module SEL, and the switching input circuit includes a second selection module SEL; The input terminal I1 of the broken line function module HSCHARC is connected to the actual load value signal of the unit, and the output terminal AV outputs the steam pressure value signal after the regulating stage after the electric load is converted; The first input end of the first selection module SEL is connected to the regulation stage pressure quality bad signal, the second input end is connected to the steam pressure value signal after the generator side regulation stage, and the third input end is connected to the steam pressure value signal after the regulation stage after the electric load conversion; The first input end of the second selection module SEL is connected to the input button after the electric load is converted, the second input end is connected to the output end of the first selection module SEL, the third input end is connected to the steam pressure value signal after the regulating stage after the electric load is converted, and the output end outputs the steam pressure value after the steam turbine regulating stage.

2. The system for preventing regulation-level pressure measurement point failure according to claim 1, characterized in that: In the main steam flow operation logic circuit, the steam pressure value signal after the regulating stage after the electric load conversion is used to replace the steam pressure value signal after the regulating stage on the machine side, and the output end of the second selection module SEL is connected to the input end of the main steam flow operation logic circuit.

3. The system for preventing regulation-level pressure measurement point failure according to claim 1, characterized in that: A third selection module SEL is added to the feedforward logic circuit. The first input end of the third selection module SEL is connected to the input button after the electric load conversion, the second input end is connected to the steam pressure value signal after the machine-side regulating stage, the third input end is connected to the steam pressure value signal after the regulating stage after the electric load conversion, and the output end is connected to the input end of the feedforward logic circuit.

4. The system for preventing regulation-level pressure measurement point failure according to claim 1, characterized in that: It also includes a pressure fault condition circuit, which includes a signal quality check module DQ and a fourth selection module SEL. The input end IN of the signal quality check module DQ is connected to the actual load value signal of the unit, and the output RLA end is connected to the third input end of the fourth selection module SEL. The first input end of the fourth selection module SEL is connected to the electric load conversion input button, and the second input end is connected to the regulation stage pressure quality bad signal.

5. The system for preventing regulation-level pressure measurement point failure according to claim 4, characterized in that: The pressure fault condition circuit is added to the small steam turbine feed water logic circuit and the boiler main control logic circuit.

Images