Voltage control by small hydro power plants integrated into a virtual power plant

A high penetration of distributed energy resources results in an increasing network voltage in times of high feed-in. Therefore, an efficient voltage control is required. Small run-off-river hydro power plants offer the opportunity to control the network voltage by reactive and active power. Thus, these units have to be connected to a virtual power plant. Within a virtual power plant, the units can be controlled by an energy management system, which is able to communicate with the several hydro power plants. By considering four scenarios, the efficiency of the various voltage control measures is investigated. Thereby, the active and reactive power feed-in by small hydro power plants is varied to control the voltage in the electrical network in times of high feed-in by photovoltaic systems. The various control measures are examined and evaluated. Besides considering voltage control by reactive and active power, also a combination of both measures is investigated.