Research On The Synchronous Generator Excitation Control System Of The Spare Power System Based On Dsp

As the energy conversion centre of the spare power system, the synchronous generator shall convert the kinetic energy of diesel engine into electric energy, input stable voltage ac power supply into the power electronics devices, and provide excitation power supply for the high-voltage generator. Just because of this ,the synchronous generator is one of most important device in the spare power system and it is extremely significant for stable operation of the whole spare power system to keep the synchronous generator stable. According to the special operation requirements of the synchronous generator , the paper has designed the excitation control system of the synchronous generator based on the TMS320LF2407.According to the operation performance requirements of the synchronous generator by the spare power system, the paper firstly has designed the excitation mode, basic configuration, main circuit and control strategy. PID control strategy is adopted which can fast and accurately regulate the stator voltage in a relatively large range, effectively restrain overshoot, ensure voltage regulating precision, and satisfy the request of the most application situations. Self-parallel excitation mode is adopted which is of simple connection, high reliability, maintenance convenience, cheap cost and inherent high initiative rapid response characteristic. The main circuit is made up of three-phase uncontrolled rectifier, BUCK chopping circuit, single-phase inverter, high-frequency transformer, single-phase uncontrolled rectifier and filter. The main circuit is of original configuration, simpleness, stabilization and reliability. The control system can easily regulate the exciting voltage and current by adjusting the width of trigger pulse of IGBT in the second-level BUCK circuit. So the control characteristic is very convenient and reliable.The paper has particularly designed the control signal interface circuit among the TMS320LF2407, excitation main circuit and the synchronous generator upon fully analyzing the excitation control system input-output signal.The paper has calculated and selected the type of the main components of the excitation main circuit. The precise math model of the synchronous generator excitation control system has been established. The simulation research of the excitation system when the synchronous generator is 4000rpm and 8000rpm no-load has been done by Matlab/Simulink. The results indicate that the synchronous generator excitation main circuit can completely satisfy the basic characteristic requirements of the spare power system.