Microprocessor based controllers for point-on-wave switching of ABB circuit breakers, for transient reduction and improved power quality.

Controlled switching is used for elimination of harmful electrical transients upon planned switching of mainly capacitor banks, shunt reactors and power transformers. The method is also gaining acceptance for reenergizing of EHV transmission lines, and replacing traditional pre-insertion resistors. Since 1986, thousands of SwitchsyncTM controllers have been delivered all over the world.

The live tank circuit breakers supplied by ABB are particularly well suited for controlled switching due to their good stability in regards to mechanical operating time and dynamic dielectric behavior. In addition, SwitchsyncTM controllers are equipped with a special adaptive control, which compensates for any systematic variations in operating time. Necessary signals for the function are received from existing instrument transformers.

The family of SwitchsyncTM Controllers consists of

All controllers have provisions for adaptive input to compensate for systematic variations in operating time of the circuit breaker. In addition, SwitchsyncTM F236, T183 and L183 have provisions for two external, predictive inputs (e.g. temperature variation, control voltage). These functions make it possible to achieve added precision in the timing of the controlled circuit breaker. They also have data memory that stores information on switching times, thus permitting condition monitoring of the circuit breaker.

Courtesy of  ABB