CN-121984214-A - Load adjusting method for nuclear turbine control system

CN121984214ACN 121984214 ACN121984214 ACN 121984214ACN-121984214-A

Abstract

The application belongs to the technical field of control of a nuclear power plant turbine, aims to solve the problems of complex load setting operation and insufficient safety verification in the existing nuclear turbine control system of the existing turbine, and discloses a load adjusting method of the nuclear turbine control system, which is used for receiving a load adjusting instruction, capturing a pulse signal based on the load adjusting instruction and locking by a trigger, after locking the pulse signal, the method comprises the steps of delaying input of a program controller, latching a current load effective value of a unit, calculating a target load value according to an instruction type, switching a load set value to the target load value, obtaining the load effective value by a load change rate generated in real time, comparing the smoothly-changed load effective value with actual load feedback, outputting an opening adjustment instruction, carrying out multiple safety verification on the opening adjustment instruction, and issuing a control instruction after verification is passed. The application can accurately adjust the load of the control system of the nuclear turbine, and obviously improves the performance of the control system of the nuclear power station.

Inventors

ZHANG ZHIQIANG
GOU JIANHUA
CAO XIWEI
CAI HONGWEI
LIU XIU
LIU JUAN
YANG NENG

Assignees

福建福清核电有限公司

Dates

Publication Date: 20260505
Application Date: 20260109

Claims (10)

1. A method for regulating load of a control system of a nuclear turbine, comprising: s101, receiving a load adjustment instruction through a preset man-machine interaction interface; S102, capturing pulse signals through a communication interface based on a load adjustment instruction and locking by a trigger; s103, after the pulse signal is locked, the program controller is put into delay; S104, latching a current load effective value of the unit, and calculating a target load value according to the instruction type; S105, switching a load set value to a target load value, and obtaining a load effective value according to a load change rate generated in real time by an online self-adaptive algorithm so as to realize smooth transition to the target load value; S106, comparing the smoothly-changed load effective value with actual load feedback through a PID controller, and outputting an opening adjusting instruction; And S107, carrying out multiple safety checks on the opening degree adjusting instruction, and issuing a control instruction after the verification is passed.
2. The method for load adjustment of a control system of a nuclear turbine according to claim 1, wherein in S101, four independent virtual buttons are provided by a preset man-machine interface.
3. The load adjustment method of a control system of a nuclear turbine according to claim 1, wherein in S103, latching a current load effective value of the unit and calculating a target load value according to a command type, comprises: s31, taking a unit thermodynamic parameter as input, and obtaining a current allowable power increment through a convex optimization framework; s32, sequentially superposing power grid frequency feedforward compensation, equipment aging self-adaptive compensation and data driving deviation suppression quantity; And S33, taking a smaller absolute value of the superposition result and the allowable increment as a target load value.
4. The load adjustment method of a control system of a nuclear turbine according to claim 3, wherein S31 includes: Constructing a main steam pressure deviation, a reheat steam temperature deviation and a high-pressure cylinder exhaust steam pressure deviation as linear matrix inequality constraint, and solving a convex optimization problem on line by taking a unit power-thermal sensitivity model as an equality constraint; and outputting the maximum unidirectional allowable power increment which does not trigger thermal protection under the current working condition.
5. A method for regulating load of a control system of a nuclear turbine according to claim 3, wherein in S32, the grid frequency feedforward compensation includes: collecting the frequency deviation and the change rate of the power grid in real time, and generating the power grid demand compensation quantity through fuzzy reasoning or linear weighting; The grid demand offset is allowed to overlap when the maximum unidirectional allowed power increment is the same number, the different numbers are discarded to avoid reverse cancellation of the primary frequency modulation of the power grid.
6. The load adjusting method of a control system of a nuclear turbine according to claim 5, wherein the input domain of fuzzy reasoning is power grid frequency deviation and change rate thereof, the output domain is power grid demand compensation amount, the membership function and the reasoning rule table are stored in a factory template form, and the unit corrects the rule weight through self-learning iteration in a debugging stage.
7. A load adjustment method for a control system of a nuclear turbine according to claim 3, wherein in S32, the equipment aging adaptive compensation includes: Maintaining an on-line throttle flow characteristic drift index updated by an exponentially weighted moving average of the most recently adjusted steady state deviation; and generating an ageing compensation quantity by a monotonically non-decreasing function, wherein the sign of the ageing compensation quantity is consistent with the direction of the command.
8. The method for load adjustment of a control system of a nuclear turbine according to claim 3, wherein the data driving bias suppression amount in S32 includes creating a first-order autoregressive model for the historical steady-state bias sequence using recursive least squares or exponentially weighted moving averages, outputting a self-learning compensation amount in a direction opposite to the historical average bias for eliminating systematic bias in advance.
9. The method for regulating load of a control system of a nuclear turbine according to claim 1, wherein in S105, the validating process of the load set value comprises inputting the load set value switched to the target load value to a load rate control module, and smoothly changing the current real-time load validating value of the unit to the target load value at a slope with a rate K at a load change rate under the condition that the program controller is triggered.
10. The load adjustment method of a control system of a nuclear turbine according to claim 1, wherein before S106 outputs an opening adjustment command, the load adjustment process to be executed is simulated in advance by using an embedded digital twin model, and if the predicted quality index exceeds the allowable range, the execution of the current adjustment is refused.

Description

Load adjusting method for nuclear turbine control system Technical Field The application belongs to the technical field of control of a steam turbine of a nuclear power plant, and particularly relates to a load adjusting method of a control system of a nuclear power steam turbine. Background The turbine control system (such as ALSTOM P320) of the nuclear power plant is mostly a special instrument control system independent of the non-security level DCS platform, and is usually connected to the non-security level DCS system of the nuclear power plant in a third party communication mode, and is designed with two control modes, namely remote control mode and local control mode. In the traditional design scheme, the nuclear turbine control system has the automatic regulation control function of the turbine rotating speed and load, after the turbine is connected into a load mode to operate, an operator can modify the regulation parameters such as a target load set value, a load rate and the like in a human-computer interface and execute a regulation control command button, so that the manual/automatic regulation control of the turbine load can be realized, and the load control precision is within +/-5 MW. However, with the gradual increase of the load control requirements of the nuclear power plant on the steam turbine, operators often need to finely adjust the load of the unit accurately so as to meet the requirements of frequency adjustment or economic distribution. At present, the main mode for realizing load fine adjustment (such as increasing or decreasing 1 MW) is manual operation of an operator, and the general flow is that the operator inputs a target load value on a human-computer interface manually, then adjusts the set load rate, clicks an execution command after confirming no error, closely focuses on the load change condition of a unit in real time, and rapidly exits after reaching the target value. This traditional approach has the following significant drawbacks: (1) The operation is complicated, namely the operator needs to perform multiple operations to finish load adjustment, and the operation is complicated by modifying multiple parameters; (2) The operation efficiency is low, namely, one-time load fine adjustment needs to be clicked, modified and continuously monitored on a human-computer interface for multiple times, so that the energy of operators is consumed, and the speed of responding to a scheduling instruction is low; (3) The risk of human error is that the operator is likely to have misoperation in the operation process, which easily causes the setting error of important adjustment control parameters (such as a target load set value of the steam turbine) and seriously affects the operation safety of a steam turbine control system; (4) The lack of standardized flow, which is different habits of different operators, results in different adjusting effects and is inconvenient for standardized management. Disclosure of Invention The application aims to provide a load adjusting method for a control system of a nuclear turbine, which solves the problems of complex load setting operation and insufficient safety verification in the control system of the conventional nuclear turbine of the conventional turbine. In order to achieve the above object, the present application provides the following technical solutions: a load adjusting method of a control system of a nuclear turbine comprises the following steps: s101, receiving a load adjustment instruction through a preset man-machine interaction interface; S102, capturing pulse signals through a communication interface based on a load adjustment instruction and locking by a trigger; s103, after the pulse signal is locked, the program controller is put into delay; S104, latching a current load effective value of the unit, and calculating a target load value according to the instruction type; S105, switching a load set value to a target load value, and obtaining a load effective value according to a load change rate generated in real time by an online self-adaptive algorithm so as to realize smooth transition to the target load value; S106, comparing the smoothly-changed load effective value with actual load feedback through a PID controller, and outputting an opening adjusting instruction; And S107, carrying out multiple safety checks on the opening degree adjusting instruction, and issuing a control instruction after the verification is passed. As an implementation manner, in S101, four independent virtual buttons are provided by the preset human-computer interaction interface. As an implementation manner, in S103, latching the current load effective value of the unit, and calculating the target load value according to the instruction type includes: s31, taking a unit thermodynamic parameter as input, and obtaining a current allowable power increment through a convex optimization framework; s32, sequentially superposing power grid frequency feed