Voltage Control using demand side resources in active distribution networks

A test feeder for an off-line simulation platform was developed. MATLAB® was selected to perform the power simulation based on its wide of application in the engineering and academic fields. Phasor models for the loads, solar PV and Wind energy was developed. The phasor solution with a variable step solver was selected as the study was concerned with the changes in current and voltage magnitudes only. For the first part of the simulation, the impact on the substation and other bus voltage profiles were examined based on conventional reactive power controlling devices. The results showed that voltage control can be achieved by OLTC transformers and shunt capacitors at the substation thereby regulating the voltage at a central point. Feeder-level control can be achieved by shunt capacitors and step voltage regulators on long distribution lines. The disadvantage of these devices is their slow response time to load fluctuations. In the second part of the simulation, the impact of inverter-based DER was used to control the voltage at the substation and local buses. The study was limited to PF control. The results show that DER cause the feeder voltage to rise during peak generation. It showed that PF control can be used to inject or absorb reactive power thereby controlling the voltage within the network. The final part showed that by controlling the PF, the number of taps of the substation OLTC transformers can be reduced.