Dynamic system load control through use of optimal voltage and VAr control

A distribution automation pilot project demonstrating optimal voltage and VAr control was recently installed at George Tripp Substation near Victoria, BC. By utilizing permissible voltage ranges defined by the CSA Standard, optimal voltage and VAr control is a powerful new distribution automation function which can be used by utilities to control demand in accordance with planning and operating objectives. The pilot system utilizes real-time data from multiple points on the 138 kV subtransmission and 25 kV distribution systems to implement optimum set points for PLC controlled load tap-changers on substation transformers and to change the status of capacitor banks located on the distribution feeders through a closed loop computer control scheme. The results of the 1997/98 winter system tests are summarized.