Design And Implementation Of High Voltage Electrostatic Precipitation Controller

Based on the characteristics of high voltage electrostatic precipitating power supply, a precipitation controller using "two-stage-control "Algorithm is designed, which resolves the two main problems in scintillation control: scintillation detect and scintillation tracking.Studying the scintillation phenomenon, three criterions in estimating scintillation are put forward, which realizes the accurate detection of scintillation. A two-stage control algorithm is adopted, in which the SCR's conducting angle is the direct control output, scintillation frequency is the input variable. This algorithm resolves the problem of tracking scintillation effectively.This high voltage electrostatic precipitation controller has 7 channels of analog input,2 channels of analog output, 12 digital inputs and 16 digital outputs. The analog input includes primary current, secondary current, primary voltage, secondary voltage, etc. Controller uses MAX 187 as the A/D converter, which ensure the sampling speed and the conversion precision in the same time. The processor unit is RCM2250 module. Rabit 2000 processor, a 128K SRAM and a 256K Flash Rom are integrated in RCM2250, which improves the performance of pricipitation controller. MAX504 is used to produce the 4~20mA current output. Based on the algorithm, the module outputs trigger pulse to SCR..This high voltage electrostatic precipitation controller has a 10Base-T Ethernet module and 3 asynchronous serial communication modules; Both RS485 and RS232 are integrated in the asynchronous serial communication modules.Experimental result indicates that the electro-scintillation rate can be controlled from 0 to 200 per minute.