Grading capacitors for high-voltage alternating current circuit-breakers – Part 1: General
|Publication Date:||1 June 2016|
|ICS Code (Power capacitors):||31.060.70|
|ICS Code (Capacitors in general):||31.060.01|
This part of the IEC 62146 series is applicable to grading capacitors used on circuit-breakers. Their function is to control the voltage distribution across the individual interrupter units of a multi-break circuit-breaker.
Grading capacitors can also be used in parallel to the interrupter unit on single break circuitbreakers to modify the Transient Recovery Voltage (TRV).
The grading capacitor is a sub-component for the circuit-breaker and shall be specified in accordance with the circuit-breaker specifications.
This standard applies to grading capacitors falling into one or both of the following categories for:
− mounting on air-insulated circuit-breakers;
− mounting on enclosed circuit-breakers (for example immersed in SF6, in oil, etc.).
The testing for each of the above applications is in some cases different.
The object of this standard is:
− to define uniform rules regarding performances, testing and rating;
− to define specific safety rules;
− to provide a guidance for installation and operation.
NOTE CIGRE Technical Brochure 368  presents a study about the operating environment of voltage grading capacitors applied to high-voltage circuit-breakers.
This standard does not apply to phase-to-earth capacitors installed on the circuit-breaker to modify the Transient Recovery Voltage.