City versus country-a comparison of two types of standardised SVC for the National Grid in England

The authors discuss the design and operational differences of static VAr compensators located in Exeter and St. John´s Wood, London. Perhaps the most obvious and significant difference is the smaller site area available, which requires a more compact design of SVC. The concept of a walk-around site and independent maintainability of each main component with other equipment still live and in service was retained in the city by adopting a different design of SVC system. The second contrast is in respect of the rating and duty of the SVCs. In each case the capability for emergency operation to support the system against undervoltage or to control overvoltages is required, but for the application within the heavy load area of the city, the float condition is used much less and the enhanced induction rating of 100 MVAr is expected to be used for prolonged periods on a daily basis