Research on Voltage and Current Acquisition from and Feedback Protection of Steam Recycling System of Power Plant Cooling Towers

Abstract The author introduces a technical method that combines dual-loop acquisition of voltage and current in the high voltage circuit and CPU automatic regulation of frequency duty ratio with high-precision voltage-to-frequency conversion chips. It is proposed to improve the accuracy of voltage and current acquisition from the steam recycling system of power plant cooling towers as well as the real-time performance, and to achieve long-term stable operation of the steam recycling system. Firstly, full wave bridge rectifiers and high voltage resistors are used to rectify high voltage into low voltage and current, which helps solve the problems involving insulation of high-voltage acquisition. Secondly, the overall circuit for voltage and current acquisition and feedback protection is designed according to the control system of the steam recycling system and the pulse frequency counting method. Finally, experimental data of output voltage, current and frequency are obtained through experiments and testing to analyze the accuracy and real-time performance of the overall circuit. The experimental results show that this method can effectively improve the accuracy of voltage and current acquisition and the real-time performance of overvoltage and overcurrent protection in the steam recycling system.