A Scheme for Coordinated Secondary Voltage Control for Systems with Multiple VAr Reserves

This paper presents a voltage control scheme for coordinating reactive power reserves, inspired by the concept of multi-agent system. Similar to an agent, the proposed controller takes on assigned tasks itself and contacts neighbors for support when needed. The control structure incorporates not only controllable VAr sources but also switched capacitor banks, resulting in increased online reactive reserves for critical contingencies. The approach is suitable for areas with penetration of FACTS devices, distributed generation connected to power systems by voltage source converter (VSC), or SVC-HVDC systems. The control structure is simple and very flexible in terms of coordination, implementation and expansion.