Hosting Capacity Enhancement Using Open UPQC in LV Distribution Networks

The deviation of the demand levels of the modern LV distribution systems due to the more loads and distributed generations connected in the same grid leads to the loss of acceptable quality of voltage. These voltage quality problems occur in case of the high difference between the power of the loads and distributed generations in the same area. Accordingly, the high loading conditions lead to the bus voltage decrease while the bus voltage increment occurs in scenarios with the excess of generation. In this condition, the successful voltage stabilization in MV/LV substation can effectively suppress the deviations of the grid voltage values. Hence, by the effective enhancement of the grid voltage quality, the higher penetration of loads will be applicable as well as the integration of more PV units towards the implementation of green energy policies. There are different custom power devices introduced in the literature which can provide the stabilization of voltage in the grids. In this paper, among the available tools, the application of Open UPQC is examined in hosting capacity improvement maintaining a desired power quality level; this capability is provided through the successful voltage regulation in the different probable high/low loading scenarios in the grid. According to the results, while the uncoordinated operation of the series and shunt devices does not have the capability of stabilization of the base grid, the Open UPQC has successfully maintained the voltage profile inside the limits in both the base case and in the presence of high load and PV penetration levels. It should be emphasized that the services of the Open UPQC are provided in an economic and effective way making the solution strategy applicable in real-world cases.