CN-121979051-A - Nuclear power plant closed-loop control system and method based on FPGA edge calculation

CN121979051ACN 121979051 ACN121979051 ACN 121979051ACN-121979051-A

Abstract

A nuclear power plant closed-loop control system and method based on FPGA edge calculation comprises a field physical layer, a sensing sampling layer, an FPGA edge calculation unit, a distributed control system and a high-voltage frequency converter, wherein the field physical layer comprises a circulating water pump and a driving motor, the sensing sampling layer comprises a high-frequency current transformer and an inlet pressure transmitter, the FPGA edge calculation unit comprises a high-speed ADC interface, a PS end and a PL end, the high-frequency current transformer and the inlet pressure transmitter are connected to the high-speed ADC interface in the FPGA edge calculation unit, the PL end comprises a preprocessing IP core, a PINN accelerating engine, a cavitation evaluation and MPC control decision module and a safety guard logic module, the early sensing of cavitation is realized by utilizing a physical mechanism, and microsecond closed-loop control is realized by acceleration of FPGA hardware.

Inventors

HUANG XINLEI
LI BIAO
JI CHENG
LIU CUILING
LIN CHENYU
HUANG YINHUA

Assignees

福建福清核电有限公司

Dates

Publication Date: 20260505
Application Date: 20260129

Claims (10)

1. A nuclear power plant closed-loop control system based on FPGA edge calculation is characterized by comprising a field physical layer, a sensing sampling layer, an FPGA edge calculation unit (10), a distributed control system (30) and a high-voltage frequency converter (20), wherein the field physical layer comprises a circulating water pump (1) and a driving motor (2), the sensing sampling layer comprises a high-frequency current transformer (4) and an inlet pressure transmitter (5), the FPGA edge calculation unit (10) comprises a high-speed ADC interface (11), a PS end (12) and a PL end (13), the high-frequency current transformer (4) and the inlet pressure transmitter (5) are connected to the high-speed ADC interface (11) in the FPGA edge calculation unit (10), the PL end (13) comprises a preprocessing IP core (131), a PINN acceleration engine (132), a cavitation evaluation and MPC control decision module (134) and a safety gate logic module (133), the preprocessing IP core (131), the PINN acceleration engine (132), the cavitation evaluation and the MPC control decision module (134) and the safety gate logic module (133) are sequentially connected, the safety gate logic module (133) is connected to the high-voltage frequency converter (20), the PS end (12) is connected to the distributed control system (20), and the distributed control system (30) is connected to the field physical layer (1) And a drive motor (2).
2. The closed loop control system of a nuclear power plant based on FPGA edge computation of claim 1, wherein the high-speed ADC interface (11) is connected with the preprocessing IP core (131) through an AXI Stream high-speed bus.
3. The closed-loop control system of the nuclear power plant based on FPGA edge calculation is characterized in that a high-frequency current transformer (4) is installed on a power cable side of a driving motor (2) in a non-invasive mode, high-frequency analog current signals reflecting the running load and cavitation characteristics of the driving motor (2) are collected in real time, an inlet pressure transmitter (5) is installed on an inlet pipeline of a circulating water pump (1), and analog pressure signals of a pump inlet are collected in real time.
4. The closed-loop control method of the nuclear power plant based on FPGA edge calculation, which is applied to the system of claim 3, is characterized by comprising the following steps: S100, sensing a physical state change of a sampling layer to acquire a physical state change of a field physical layer, wherein a high-frequency current transformer (4) acquires a high-frequency analog current signal reflecting the running load and cavitation characteristics of a driving motor (2) in real time, and an inlet pressure transmitter (5) acquires an analog pressure signal of an inlet of a circulating water pump (1) in real time; S200, uniformly accessing two paths of analog signals into a high-speed ADC interface (11) at the front end of an FPGA edge computing unit (10), and synchronously sampling and quantizing the two paths of analog signals by the high-speed ADC interface (11) to convert continuous time domain analog signals into discrete digital signals; S300, the signal digitized by the S200 enters a PL terminal (13); S400, the high-voltage frequency converter (20) receives a control instruction output by the PL end (13) and adjusts the rotating speed of the driving motor (2) to enable the system to be separated from a cavitation area.
5. The method for closed loop control of a nuclear power plant based on FPGA edge calculation of claim 4, wherein S300 comprises the following steps: S301, a digital signal flow firstly enters a preprocessing IP core (131) of a PL end (13), the preprocessing IP core (131) executes denoising processing on the signal, and a fast Fourier transform algorithm is adopted to extract the high-frequency torque pulsation frequency characteristic of the circulating water pump (1) when cavitation occurs, and the characteristic tensor data is constructed by normalizing the high-frequency torque pulsation frequency characteristic; S302, inputting the preprocessed characteristic tensor data into PINN acceleration engine (132), inverting PINN acceleration engine (132) in real time to calculate the local pressure field distribution and bubble radius evolution trend of the impeller surface of the circulating water pump (1), and transmitting inversion parameters to cavitation evaluation module (134); S303, judging cavitation risk by a cavitation evaluation and MPC control decision module (134), and generating a command to be transmitted to a security guard logic module (133); S304, the security guard logic module (133) performs verification, if the verification is passed, a final security control instruction is output to the high-voltage frequency converter 20, and if the verification is not passed, the security guard logic module is forcedly switched to a preset security operation mode.
6. The method for closed loop control of a nuclear power plant based on FPGA edge computation of claim 5, wherein in S302, PINN is used for accelerating physical constraints of a hydrodynamic Navier-Stokes equation and a bubble dynamics Rayleigh-plaset equation in real-time inversion of an engine (132) through a loss function.
7. The method for closed-loop control of a nuclear power plant based on FPGA edge calculation as set forth in claim 5, wherein in S303, the cavitation evaluation and MPC control decision module (134) extracts the minimum pressure pmin on the impeller surface in the S302 reaction, and calculates the effective cavitation margin NPSHa in combination with the current saturated vapor pressure pv of the fluid, Pin is the actual measurement value of the pressure transmitter (5) in the step S100, and the internal flow velocity v and the pressure distribution p v are obtained by inverting the PINN acceleration engine (132) of the step S302 through a physical equation; The NPSHr is an inherently necessary cavitation allowance of the circulating water pump (1), is a safety zone of cavitation risk when NPSHa/NPSHr is more than 1.3, is a warning zone of cavitation risk when the NPSHa/NPSHr is more than 1.08 and is used for generating a rotating speed fine adjustment control command of the driving motor (2), is a danger zone of cavitation risk when the NPSHa/NPSHr is more than 1.08, is used for generating a rotating speed rapid inhibition command of the driving motor (2), and is transmitted to the safety guard logic module (133).
8. The method for closed loop control of a nuclear power plant based on FPGA edge calculation of claim 5, wherein in S304, a rotating speed instruction of a driving motor (2) in a generated instruction is confirmed to be 85-100% of a rated rotating speed of the motor, and PINN acceleration engine (132) inverts calculated local pressure field distribution and bubble radius evolution trend confidence of the impeller surface of the circulating water pump (1) in real time to be higher than 90%.
9. The method for closed loop control of a nuclear power plant based on FPGA edge calculation of claim 8, wherein in S304, the safe operation mode is to keep the current rotation speed of the driving motor (2).
10. The method for closed-loop control of a nuclear power plant based on FPGA edge computation of claim 5, further comprising S500, wherein the verification result of the security gate logic module (133) is sent to the PS terminal (12), and the PS terminal (12) interacts data with the distributed control system (30).

Description

Nuclear power plant closed-loop control system and method based on FPGA edge calculation Technical Field The invention relates to the technical field of intelligent operation and maintenance and industrial control of nuclear power plant equipment, in particular to a closed-loop control system and method based on FPGA (field programmable gate array) edge calculation. Background The nuclear power plant circulating water pump (CRF) is a key device of a power plant cold source system, and the operation stability of the CRF directly influences the vacuum degree of a condenser and the thermal efficiency of a unit. Due to the influence of factors such as tidal water level change, blockage of a rotary filter screen and the like, the circulating pump is extremely easy to deviate from an optimal working condition point to cause cavitation (Cavitation). Cavitation can lead to impeller erosion and vibration aggravation, and the serious case can cause broken shaft accident, causes the unplanned shut down. The prior art mainly has the following defects: (1) The monitoring means is lagged, and the traditional monitoring method mainly relies on an acceleration sensor to collect mechanical vibration signals. However, when the vibration signal is obviously abnormal, cavitation is often developed to a certain extent, and physical damage is caused to the impeller, so that the early warning capability is lacking, and the early warning capability is realized. (2) The unreliability of the pure data driven AI model is that the existing deep learning fault diagnosis method relies on massive fault samples for training. However, the reliability of the nuclear-level equipment is extremely high, and the lack of sufficient cavitation fault data (i.e. the problem of "zero sample" or "small sample") results in a pure data driven model with poor generalization capability under unknown conditions and lack of physical interpretability, which is difficult to pass nuclear security inspection. (3) And (3) the time delay and the potential safety hazard of cloud computing are that massive high-frequency data are transmitted to the cloud for processing, and network time delay (Latency) and data security risks exist. For cavitation, which is a transient fluid phenomenon, millisecond-level control response is crucial, and hard real-time control requirements are difficult to meet by using an industrial control computer or a cloud architecture. Disclosure of Invention The invention aims to provide a closed-loop control system and method based on FPGA edge calculation, which solve the problems of monitoring lag, lack of interpretability of an AI model and slow control response in the prior art. The data loss is compensated by utilizing a physical mechanism, early perception of cavitation is realized, and microsecond closed-loop control is realized through acceleration of FPGA hardware. The technical scheme is that the nuclear power plant closed-loop control system based on FPGA edge calculation comprises a field physical layer, a sensing sampling layer, an FPGA edge calculation unit, a distributed control system and a high-voltage frequency converter, wherein the field physical layer comprises a circulating water pump and a driving motor, the sensing sampling layer comprises a high-frequency current transformer and an inlet pressure transmitter, the FPGA edge calculation unit comprises a high-speed ADC interface, a PS end and a PL end, the high-frequency current transformer and the inlet pressure transmitter are connected to the high-speed ADC interface in the FPGA edge calculation unit, the PL end comprises a preprocessing IP core, a PINN acceleration engine, a cavitation evaluation and MPC control decision module and a safety gate logic module, the preprocessing IP core, the PINN acceleration engine, the cavitation evaluation and MPC control decision module and the safety gate logic module are sequentially connected, the safety gate logic module is connected with the high-voltage frequency converter and the PS end, the PS end is connected with the distributed control system, and the circulating water pump and the driving motor in the field physical layer are controlled by the high-voltage frequency converter. The high-speed ADC interface is connected with the preprocessing IP core through an AXI Stream high-speed bus. The high-frequency current transformer is non-invasively arranged on the power cable side of the driving motor, and is used for collecting high-frequency analog current signals reflecting the running load and cavitation characteristics of the driving motor 2 in real time, and the inlet pressure transmitter is arranged on an inlet pipeline of the circulating water pump and is used for collecting analog pressure signals of the inlet of the pump in real time. A nuclear power plant closed-loop control method based on FPGA edge calculation comprises the following steps: S100, sensing a physical state change of a sampling layer to acquire a p