Abstract: A modular power flow control system is described for optimizing power flow control in a multi-phase power transmission system. Identical impedance injection modules are arranged in an m×n matrix, where m is the number of series-connected modules inserted into each phase (forming a leg of the installed bank of modules), and n is the number of parallel-connected legs per phase. Each impedance injection module in a phase is configurable to collectively insert a pre-determined (controllable) power control waveform into the phase to which it is attached. The modular flow control system is agile with respect to configurability, reconfigurability, maintenance, size, weight, and cost.

Abstract: A system architecture and method for enabling hierarchical intelligent control with appropriate-speed communication and coordination of control using intelligent distributed impedance/voltage injection modules, local intelligence centers, other actuator devices and miscellaneous FACTS coupled actuator devices is disclosed. Information transfer to a supervisory utility control is enabled for responding to integral power system disturbances, system modelling and optimization. By extending the control and communication capability to the edge of the HV power grid, control of the distribution network through FACTS based Demand response units is also enabled.

Abstract: This patent discloses an active impedance-injection module for dynamic line balancing of a high-voltage (HV) transmission line. The impedance-injection module comprises a plurality of transformers each having a primary winding in series with a HV transmission line. Each transformer also has secondary windings, each connected to an individual electronic converter. The plurality of secondary windings are electrically isolated from the associated primary winding and extract power from the HV transmission line for operation of the converters and other circuits connected to the secondary windings. The active impedance-injection module is enabled to generate a controlled impedance, inductive or capacitive, to be impressed on the HV transmission line.

Abstract: A system architecture and method for enabling hierarchical intelligent control with appropriate-speed communication and coordination of control using intelligent distributed impedance/voltage injection modules, local intelligence centers, other actuator devices and miscellaneous FACTS coupled actuator devices is disclosed. Information transfer to a supervisory utility control is enabled for responding to integral power system disturbances, system modelling and optimization. By extending the control and communication capability to the edge of the HV power grid, control of the distribution network through FACTS based Demand response units is also enabled.

Abstract: The power transmission tower mounted series injection transformer (TMIT) injects impedance and/or voltage on a transmission tower power line. A tension bearing tower uses vertical and horizontal insulators to support and stabilize the TMIT. The TMIT can be much heavier than a transformer device clamped to the high-voltage transmission line. The TMIT is connected in series with the tension bearing tower's jumper allowing it to use a multi-turn transformer. By operating at the line voltage potential, the TMIT does not require the large bushings and oil drums used by sub-station injection transformers.

Abstract: Disclosed is a method for reducing the variation in voltage, due to Ferranti effect, using the impedance injection capability of distributed impedance injection modules. The Ferranti effect is an increase in voltage occurring at the receiving end of a long transmission line in comparison to the voltage at the sending end. This effect is more pronounced on longer lies and underground lines when the high-voltage power lines are energized with a very low load, when there is a change from a high load to a very light load, or the load is disconnected from the high-voltage power lines of the power grid. This effect creates a problem for voltage control at the distribution end of the power grid.

Abstract: Flexible AC transmission system (FACTS) enabling distributed controls is a requirement for power transmission and distribution, to improve line balancing and distribution efficiency. These FACTS devices are electronic circuits that vary in the type of services they provide. All FACTS devices have internal circuitry to handle fault currents. Most of these circuits are unique in design for each manufacturer, which make these FACTS devices non-modular, non-interchangeable, expensive and heavy. One of the most versatile FACTS device is the static synchronous series compensator (SSSC), which is used to inject impedance into the transmission lines to change the power flow characteristics. The addition of integrated fault current handling circuitry makes the SSSC and similar FACTS devices unwieldy, heavy, and not a viable solution for distributed control. What is disclosed are modifications to FACTS devices that move the fault current protection external to the FACTS device and make them modular and re-usable.

Abstract: Distributed series reactance modules and active impedance injection modules that are adapted to operating with electric power transmission lines over a wide range of transmission voltages are disclosed. Key elements include a virtual ground, an enclosure that acts as a Faraday shield, radio frequency or microwave control methods and the use of corona rings.

Abstract: Distributed static synchronous series compensators (DSSSCs) which may also be designated tower routers capable of injecting series inductive or capacitive impedances to enable distributed power-flow control. When a large number of these (a fleet of) DSSSCs are distributed over the grid for power-flow control, it is necessary to ensure that coordinated communication and control capabilities are also established, enabling fast reaction to changes that can exist across the grid. A system architecture and method for enabling localized high-speed low-latency intelligent control with communications between subsections (local network) of the grid along with communication to the central Grid operations center at the utility for supervisory control is disclosed herein.

Abstract: Distributed static synchronous series compensators (DSSSCs) which may also be designated tower routers capable of injecting series inductive or capacitive impedances to enable distributed power-flow control. When a large number of these (a fleet of) DSSSCs are distributed over the grid for power-flow control, it is necessary to ensure that coordinated communication and control capabilities are also established, enabling fast reaction to changes that can exist across the grid. A system architecture and method for enabling localized high-speed low-latency intelligent control with communications between subsections (local network) of the grid along with communication to the central Grid operations center at the utility for supervisory control is disclosed herein.

Abstract: Active impedance-injection module enabled for distributed power flow control of high-voltage (HV) transmission lines is disclosed. The module uses transformers with multi-turn primary windings, series-connected to high-voltage power lines, to dynamically control power flow on those power lines. The insertion of the transformer multi-turn primary is by cutting the line and splicing the two ends of the winding to the ends of the cut high-voltage transmission line. The secondary winding of the transformer is connected to a control circuit and a converter/inverter circuit that is able to generate inductive and capacitive impedance based on the status of the transmission line. The module operates by extracting power from the HV transmission line with the module floating at the HV transmission-line potential. High-voltage insulators are typically used to suspend the module from transmission towers, or intermediate support structures. It may also be directly suspended from the HV transmission line.

Abstract: This patent discloses an active impedance-injection module for dynamic line balancing of a high-voltage (HV) transmission line. The impedance-injection module comprises a plurality of transformers each having a primary winding in series with a HV transmission line. Each transformer also has secondary windings, each connected to an individual electronic converter. The plurality of secondary windings are electrically isolated from the associated primary winding and extract power from the HV transmission line for operation of the converters and other circuits connected to the secondary windings. The active impedance-injection module is enabled to generate a controlled impedance, inductive or capacitive, to be impressed on the HV transmission line.

Abstract: A series injection device includes a power splitter coupled to two or more lines of an AC power system. The power splitter includes a coupling transformer for each phase of a single phase or polyphase AC circuit that includes the two or more lines. Each of the coupling transformers couples one of the phases of the two or more lines. The power splitter is configured to inject a first voltage of a first polarity into one or more of the two or more lines and inject a second voltage of a second polarity opposite the first polarity into at least one of the two or more lines via the same coupling transformers used to inject the first voltage. The first and the second voltages are controllable, and may or may not be independently variable.

Abstract: This patent discloses an active impedance-injection module for dynamic line balancing of a high-voltage (HV) transmission line. The impedance-injection module comprises a plurality of transformers each having a primary winding in series with a HV transmission line. Each transformer also has secondary windings, each connected to an individual electronic converter. The plurality of secondary windings are electrically isolated from the associated primary winding and extract power from the HV transmission line for operation of the converters and other circuits connected to the secondary windings. The active impedance-injection module is enabled to generate a controlled impedance, inductive or capacitive, to be impressed on the HV transmission line.

Abstract: A wind turbine is disclosed having a generator and rectifier and structured to provide direct current power that in one form is medium voltage direct current (MVDC). The wind turbine includes a crowbar circuit arranged to protect from a condition such as an overvoltage. The crowbar can be activated based on a voltage measurement or rate of change of voltage. A resistor can be coupled to the crowbar to absorb excess power provided by the generator during the overvoltage condition. Individual wind turbines in a wind farm can each have individual crow bars that can be activated based on local measurement of a voltage condition. In some forms the crowbar can be coupled with a transformer, for example coupled with a tertiary winding of a three winding transformer.

Abstract: According to one aspect of the teachings herein, a system for obtaining electricity from wind turbines provides advantageous operation with respect to offshore wind turbines where the size and weight of electricity generation and collection equipment are key considerations. The contemplated system includes an apparatus that is configured for collecting wind-generated electricity at a fixed low frequency and at a desired collection voltage, based on the advantageous configuration and use of a modular multilevel converter or MMC.

Abstract: Distributed static synchronous series compensators (DSSSCs) which may also be designated tower routers capable of injecting series inductive or capacitive impedances to enable distributed power-flow control. When a large number of these (a fleet of) DSSSCs are distributed over the grid for power-flow control, it is necessary to ensure that coordinated communication and control capabilities are also established, enabling fast reaction to changes that can exist across the grid. A system architecture and method for enabling localized high-speed low-latency intelligent control with communications between subsections (local network) of the grid along with communication to the central Grid operations center at the utility for supervisory control is disclosed herein.

Abstract: A system architecture and method for enabling hierarchical intelligent control with appropriate-speed communication and coordination of control using intelligent distributed impedance/voltage injection modules, local intelligence centers, other actuator devices and miscellaneous FACTS coupled actuator devices is disclosed. Information transfer to a supervisory utility control is enabled for responding to integral power system disturbances, system modelling and optimization. By extending the control and communication capability to the edge of the HV power grid, control of the distribution network through FACTS based Demand response units is also enabled.

Abstract: According to one aspect of the teachings herein, various feeder connection arrangements and architectures are disclosed, for collecting electricity from wind turbines in an offshore collection grid that operates at a fixed low frequency, e.g., at one third of the targeted utility grid frequency. Embodiments herein detail various feeder arrangements, such as the use of parallel feeder connections and cluster-based feeder arrangements where a centralized substation includes a common step-up transformer for outputting electricity at a stepped-up voltage, for low-frequency transmission to onshore equipment. Further aspects relate to advantageous generation arrangements, e.g., tower-based arrangements, for converting wind power into electrical power using, for example, medium-speed or high-speed gearboxes driving generators having a rated electrical frequency for full-power output in a range from about 50 Hz to about 150 Hz, with subsequent conversion to the fixed low frequency for off-shore collection.

Abstract: The power transmission tower mounted series injection transformer (TMIT) injects impedance and/or voltage on a transmission tower power line. A tension bearing tower uses vertical and horizontal insulators to support and stabilize the TMIT. The TMIT can be much heavier than a transformer device clamped to the high-voltage transmission line. The TMIT is connected in series with the tension bearing tower's jumper allowing it to use a multi-turn transformer. By operating at the line voltage potential, the TMIT does not require the large bushings and oil drums used by sub-station injection transformers.