A robust and stable PLC based control system for 40kJ/25kV EMM system

This paper describes the PLC based control system developed for a 40kJ/25kV Electro-magnetic machining (EMM) system. In EMM system large capacitor banks is charged with high voltage to store large energy and the banks is made to discharge into a coil within few milli-seconds using a triggered spark gaps. During discharge of the capacitor large surges and transients are generated in the system. The control system monitors/controls and interlocks all the units of the system for proper operation. The control system is the only subsystem which is eclectically connected to all the low and high voltage subsystems. Care should be taken at the signal interfacing with the control system to protect the control system.