Automatic Voltage Regulator
Automatic Voltage Regulator (AVR) stabilize voltages as loads change. Generators ship electrical power production, or standby power systems, will have automatic voltage regulators (AVR) to stabilize their voltages as the load on the generators changes. Where a generator is connected in parallel with other sources such as an electrical transmission grid, changing the excitation has more of an effect on the reactive power produced by the generator than on its terminal voltage, which is mostly set by the connected power system. Where multiple generators are connected in parallel, the AVR system will have circuits to ensure all generators operate at the same power factor. AVRs on grid-connected power station generators may have additional control features to help stabilize the electrical grid against upsets due to sudden load loss or faults.