IMPLEMENTATION OF ACTIVE AND REACTIVE POWER FLOW CONTROL IN A SINGLE PHASE MICROGRID

Abstract

A microgrid is a miniature version of a large power grid, and its purpose is to operate autonomously and to increase the reliability of the power system in a naval installation. It is a local area power system, which is able to operate either as a subset of a main grid or in an autonomous mode (islanded). The power flowing from a utility to a microgrid and vice-versa has two components: 1) active power, which is the real power that can be transformed from electric to non-electric by the loads; and 2) reactive power, which is generated by inductive loads, such as electric motors. The presence of the latter category lessens the energy efficiency of an installation, reduces the real energy, and increases the cost of the electricity for the consumer. The compensation for the reactive power and simultaneously the control of the active power is obtained by a highly developed electronic system, called the Energy Management System (EMS). It manages the distributed energy resources in a microgrid, such as batteries, and renewable energy sources to ensure that electricity is available to an installation when the main grid is off. In our research, four different methods of EMS control have been examined in order to regulate the electricity delivered to the consumer for maximum available power and to reduce the cost of the electricity. Simulated plots are presented and validated by experimental waveforms measured on a laboratory prototype.