Abstract: Provided is a series capacitor for controlling a flow of power on a transmission line, and includes a filter circuit, and a thyristor-controlled circuit, wherein an interconnection and operation of the filter circuit and the thyristor-controlled circuit are performed based on a coordination of control thereof, to connect to a series capacitor bank on a transmission line.

Abstract: Provided is a series capacitor for controlling a flow of power on a transmission line, and includes a filter circuit, and a thyristor-controlled circuit, wherein an interconnection and operation of the filter circuit and the thyristor-controlled circuit are performed based on a coordination of control thereof, to connect to a series capacitor bank on a transmission line.

Abstract: A system is disclosed including a plurality of metal oxide varistors (MOVs) columns connected in parallel, and at least one fuse connected to an MOV column. The fuse(s) are configured to isolate the MOV column in the case that the fuse is activated.

Abstract: Systems and methods for protecting a series capacitor bank are provided. According to one exemplary embodiment of the invention, there is disclosed a capacitor protection circuit. The capacitor protection circuit may include a capacitor bank, a pilot circuit and a main commutation gap. The pilot circuit and the main commutation gap may be provided in parallel electrical communication with the capacitor bank. Additionally, one or more plasma injectors may be provided in series electrical communication with the pilot circuit. The plasma injectors may be operable to provide partially or completely ionized plasma across the main commutation gap to make conductive the main commutation gap.

Abstract: Systems and methods for protecting a series capacitor bank are provided. According to one exemplary embodiment of the invention, there is disclosed a capacitor protection circuit. The capacitor protection circuit may include a capacitor bank, a pilot circuit and a main commutation gap. The pilot circuit and the main commutation gap may be provided in parallel electrical communication with the capacitor bank. Additionally, one or more plasma injectors may be provided in series electrical communication with the pilot circuit. The plasma injectors may be operable to provide partially or completely ionized plasma across the main commutation gap to make conductive the main commutation gap.

Abstract: Systems and methods of dynamic reactive power support for a power transmission system are provided. In one embodiment, a method of dynamic reactive power support for a power transmission system includes at least one circuit breaker connecting a shunt capacitor bank containing at least one shunt capacitor with a metal oxide varistor (MOV) connected in parallel. A controller is used to detect a voltage drop at the power transmission system (e.g., substation bus). In response to detecting the voltage drop, the controller closes the circuit breaker(s) connecting the shunt capacitors to the power transmission system. The controller then monitors at least one MOV to detect a current flow. Upon detection of a current flow in the MOV, the controller disconnects one or more shunt capacitors from the power transmission system by opening one or more circuit breakers. The shunt capacitors may be disconnected simultaneously, sequentially, in groups, or otherwise.

Abstract: Systems and methods of dynamic reactive power support for a power transmission system are provided. In one embodiment, a method of dynamic reactive power support for a power transmission system includes at least one circuit breaker connecting a shunt capacitor bank containing at least one shunt capacitor with a metal oxide varistor (MOV) connected in parallel. A controller is used to detect a voltage drop at the power transmission system (e.g., substation bus). In response to detecting the voltage drop, the controller closes the circuit breaker(s) connecting the shunt capacitors to the power transmission system. The controller then monitors at least one MOV to detect a current flow. Upon detection of a current flow in the MOV, the controller disconnects one or more shunt capacitors from the power transmission system by opening one or more circuit breakers. The shunt capacitors may be disconnected simultaneously, sequentially, in groups, or otherwise.

Abstract: An apparatus for detecting currents in a three-phase power transmission system includes a first detection circuit electrically coupled to a first phase of the three-phase transmission system, a second detection circuit electrically coupled to a second phase of the three-phase transmission system different than the first phase, and an event output switch electrically coupled to the first detection circuit and the second detection circuit and configured to actuate when a subsynchronous current at least one of the first phase and the second phase exceeds a pre-selected subsynchronous current setpoint.

Abstract: An apparatus for detecting currents in a three-phase power transmission system includes a first detection circuit electrically coupled to a first the three-phase transmission system, a second detection circuit electrically coupled to a second phase of the three-phase transmission system different than the first phase, and an event output switch electrically coupled to the first detection circuit and the second detection circuit and configured to actuate when a subsynchronous current at least one of the first phase and the second phase exceeds a pre-selected subsynchronous current setpoint.