Control of prosumer voltage sources in distribution grids

Power flow in three-phase distribution grids containing single-phase prosumer voltage sources strongly depend on the RMS value of the voltage of these sources and their phase shifts in relation to the grid voltage. The ideal way to control single-phase prosumer sources should guarantee no return active power to the MV grid through a distribution transformer and no additional reactive power flows in the LV grid. This means that the active power of one-phase voltage source is consumed by other single-phase customers (in the same phase or in others phases) and the reactive power of this source is equal zero. The paper presents the results of the investigations of the dynamic control system a single-phase voltage source which allows meeting these conditions. On the basis of steady states calculations, static characteristics of the above mentioned control, needed to determine of the proper working point of a prosumer source were also obtained. Control process is as control of the RMS value and phase angle of the voltage source against the phase voltage of the LV grid, to which the source is connected, with simultaneous control of the current phase angle issued by the power source against voltage. The obtained results of dynamic simulations and static calculations would help to develop an area-wide uniform algorithm to control prosumer sources.