Research On Primary Frequency Modulation Transmission Device And Control Strategy Of Power System

Electric energy is the foundation of the development of modern society,and China is a large country of electricity consumption,so the safe and stable operation of electric energy is essential.In recent years,thermal power plants have successively switched over large loads or the peripheral circuits have failed,resulting in instantaneous inrush current,resulting in overshoot of the analog transmitter output signal,which caused the AGC to withdraw and seriously endanger the stable operation of the power grid.The root cause of the failure is that the traditional transmitter cannot overcome the reverse overshoot caused by the time division multiplier in one frequency modulation.At the same time,with the rapid development of new energy in China,the proportion of the power grid is increasing,and new energy has become a factor affecting the stability of the power grid one of the important factors of operation.In 2018,the country released a document that the new energy system participated in a frequency modulation.Therefore,it is of great significance to study and improve the primary frequency modulation of the power system.According to the actual demand of the power grid,this paper develops a primary frequency modulation transmission device,and studies the control strategy that conforms to the primary frequency regulation.First,the paper introduces the power system and related concepts of primary frequency modulation,builds models of thermal power plants and new energy stations,and explains the topology of this paper.Secondly,the hardware circuit of a frequency modulation transmission device is designed,including frequency signal conditioning circuit,mold-in and mold-out circuit,CPU core circuit,analog wind power plant platform,etc.In terms of software and data processing,each subroutine is implemented under the framework of the FreeRTOS operating system;the adaptive Kalman filter algorithm is improved,the BP neural network algorithm is transplanted,and the frequency prediction accuracy of the transmission device is realized;the related control strategy of one frequency modulation.And an auxiliary analysis system is designed for grid evaluation,which communicates with the transmission device to display real-time data and curves,and intelligently calculates the number of effective over-limits and integrated power.In the end,this paper has conducted experimental tests on the power,frequency accuracy,mold input,mold output accuracy,new energy background system,auxiliary analysis system,etc.The results show that the device can accurately measure the secondary value of the generator and achieve corresponding output and control at the same time;it has strong robustness and is of great significance for the primary frequency modulation of thermal power,wind power and photovoltaic power system.