Hybrid Power Filter to Enhance Power Quality in a Medium-Voltage Distribution Network

This paper deals with the problem of reactive power and harmonics in a standard medium-voltage (MV) distribution network. It proposes a simple and inexpensive solution to enhance power quality when a particular connection to the high-voltage transmission network is required. It presents the design of a hybrid active filter topology connected to the MV level of a power distribution system. Its main task is to regulate a 132-kV voltage level. Reconfiguration of the power delivery network imposes new constraints in a distribution substation so that the reactive compensation should be increased. The topology of a shunt hybrid active filter is analyzed. It is built with the series connection of a passive filter and a low-rated active filter. The proposed filter is directly connected to a 13.8-kV level with no need of a step-down transformer. The possibility of different levels of reactive power compensation is implemented. The proposal shows very good performance for different load demands.