Reactor coolant pump rotation speed measuring method based on FPGA

Abstract

The invention belongs to the nuclear power technical field and specially discloses a reactor coolant pump rotation speed measuring method based on an FPGA. The method is characterized by carrying out transient voltage suppression and electrostatic protection on a rotation speed sensor signal of a coolant pump; then, shaping the obtained rotation speed sensor signal into a single-polarity square wave signal; after carrying out lowpass filtering, carrying out optoelectronic isolation on the signal; determining a pulse count value of a high-speed clock pulse signal with high-speed clock pulse frequency in the FPGA being a reference; obtaining a reactor coolant pump rotation speed value; after carrying out value limitation processing, converting the rotation speed value into a digital signal; and outputting the digital signal to a current-type DAC device through a high-speed figure isolation chip. Preliminary calculation of the coolant pump rotation speed is carried out through high-speed clock pulses in the FPGA, so that, compared with that of the existing method, measurement accuracy is improved greatly; and meanwhile, pure hardware characteristics of the FPGA are utilized, and the method has higher reliability, compared with the conventional software processing.

Description

technical field [0001] The invention belongs to the technical field of nuclear power, and in particular relates to a method for measuring the rotational speed of a coolant pump. Background technique [0002] Among the existing speed measurement methods, at present, the domestic second-generation nuclear power plant reactor coolant pump speed measurement adopts the products of the French Ansaldo company, with the 8051 series microcontroller as the core, supplemented by the PLD expansion circuit, and the fixed value comparison adopts the dial set up. Years of operation have shown that Ansalodo’s products have the following problems: 8051-type microcontrollers are used as the core, and there is a potential for software to run away; the setting of the fixed value is set by a mechanical dial, which has poor reliability and is easy to be changed by mistake; The rotational speed output adopts analog quantity isolation, which has low precision and large time drift; the present inve...

AI Technical Summary

Problems solved by technology

Years of operation have shown that Ansalodo’s products have the following problems: 8051-type microcontrollers are used as the core, and there is a potential for software to run away; the setting of the fixed value is set by a mechanical dial, which has poor reliability and is easy to be changed by mistake; The rotational speed output adopts analog isolation, which has low precision and large time drift; this invention is a rotational speed measurement method designed to improve the reliability and accuracy of the reactor cooling pump rotational speed measurement

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