VARIABLE INDUCTANCE CURRENT LIMITING REACTOR CONTROL SYSTEM FOR ELECTROSTATIC PRECIPITATOR

摘要

A method and apparatus for varying an electrically variable current limiting reactor (VICLR)(16) are provided in cooperation with an electrostatic precipitator automatic voltage control system. The inductance of VICLR (16) is varied by altering the DC current in control winding (66) of VICLR (16). A power source (10) connects serially to an inverse parallel SCR1 and SCR2, to VICLR (16), and to a TR set comprising a transformer (18) and rectifier (20) which supply power to precipitator (22). System electrical characteristics on both sides of the TR set are monitored. Computer (40) uses these monitored values to continuously calculate form factor and fractional conduction values. Step-down transformer (60) is connected to solid state relay (62) which is in turn connected to full wave bridge rectifier (64). Rectifier (64) is connected to control winding (66) of VICLR (16). Solid state relay (62) is also connected to computer (40). Solid state relay (62) can be triggered on each half cycle thereby providing DC current pulses to VICLR (16). The number of pulses supplied to said control winding within a predetermined time span can be altered thereby changing the net current in control winding (67) of VICLR (16), and hence, altering the inductance. The number of half cycles applied may be manually altered by an operator or responsive to system operating conditions, including but not limited to, form factor and fractional conduction.