Reactive Power Dispatching Among Generating Units Connected to Point of Common Coupling

When more than one source, same or different type, are connected to same point of common in the power plant, it is necessary to determine that only in-service sources with automatic voltage regulation capabilities share reactive load equally as a percentage of their dynamic reactive capability. By doing this, for any system voltage disturbance, equalized responses and maximum reactive power support from power plant units and plant as a whole is achieved. In this paper the methods for determination of dynamic reactive capability according to different criteria of different sources connected to electrically same point are given. The advantages and disadvantages are analysed and the most advantageous method is suggested. This method maximizes dynamic reactive power support from more sources by securing simultaneous exhaustion of the control reserves and provides the basis for further optimizations and equal opportunities for fair participation in voltage service market.