Design Of Excitation Controller Of Diesel Generator

Diesel generator are widely used in important departments and occasions without electrical nets such as open country, acted as standby power supply or movable power supply. It plays a key role for generator running safely and steadily, and assuring power supply quality. But the existing former digital excitation voltage regulator of this generator can't meet the demand for automatically regulating voltage, because it has many defects such as the strict demand of electro circuit technics, the phenomenon of temperature excursion, a few of functions, the discommodiousness of maintenance and so on. This paper based on the company's demand, studied the excitation control system, and with respect to characteristic of harmonious wave excitation brushless generator, a new type of diesel generator excitation controller based on DSP(TMS320F2812) is designed.We use TMS320F2812 DSP chip as a core to design the hardware and software of excitation controller, which is 32 bit pointing chip produced by TI Company, and give a detailed presentation of every module,hardware schematic diagraim,software flowchart and a part of key subprogram. This newly designed excitation controller has three characteristics as below:It combines exterior AD with interior AD to AC sampling.This dissertation choose a 16 bit exterior parallel ADC. ADS8364 to synchronous sampling to six electrical signal: Ua,Ub,Uc,Ia,Ib and Ic. With this, it can limit the quantitative and nonlinear error effectively, improve the sampling precision, and ensure the electrical parameters which be calculated be more close to real numerical value.Fuzzy PID control algorithm has been choosen as the excitation control algorithm. This can be obtained by programming inside the DSP. In order to regulate excitation current, controller calculates high voltage level proportionment which output by PWM, to control the communication and close of IGBT. Comparing with tradidional PID, fuzzy PID control algorithm can overcome complicated system's localization, such as: nonlinear,time changing etc., and have a better effect on excitation control of generator. Bases on excitation control, it extends a lot of modules, such as: LCD display,keyboard,SCI interface,alarming,closedown modules, etc. These can check and measure,give an alarm to malfunction,shutdown to diesel generator, and also can exchange parameter via a series of communicate interfaces .With these, carry out the remote control and remote survey to the diesel generator.At last, from a practical experiment to excitation controlling, this controller exhibit a good result of voltage regulate characteristic and every module exhibit works well.