Static and dynamic VAR planning to support widespread penetration of distributed generation in distribution system

Integration of small distributed generation (DG) units to weak distribution system is a major concern for power system engineers. Recent grid standards demand small DG operation with power factor control mode. Lack of sufficient reactive power support brings the problem of slow voltage recovery under post-fault condition. This paper presents a comprehensive VAR planning with a mixture of both static and dynamic compensators. In a system with number of DG units, a suitable location has been sorted out for minimum number of STATic COMpensator (STATCOM) to keep DG units remain interconnected. With help of cost analysis, STATCOM rating has been minimized to ensure economic voltage restoration, which eventually increase DG intake in distribution system. An IEEE industrial test system with various motor loads has been used for simulation and analysis.