Application of cost-effective solution to ageing 11kV withdrawable switchboard

With a view to providing a safe working environment and upholding a reliable distribution network, CLP Power undertook an 11kV Ageing Switchgear Refurbishment Program (for a specific switchboard type) in 2008. The refurbishment program includes the replacement of the vacuum circuit breaker trolleys with age of 25 years or more, installation of humidity sensor controller and enhancement of internal-arc protection of the switchboard. In summary, the retrofit program on the 11kV switchboard delivers the Operation and Maintenance benefits through: 1. reinforcing the system security and integrity by replacing ageing vacuum circuit breaker trolleys. 2. achieving a higher degree of operational safety with enhanced internal arc protection implementation. 3. encouraging recycling of parts as one of the environmental initiatives. This paper discusses CLP Power´s experience on the 11kV switchboard refurbishment program. The benefits brought by the program as well as challenges experienced are also highlighted.