Abstract: In prior art grid systems, power-line control is done by substation based large systems that use high-voltage (HV) circuits to get injectable impedance waveforms that can create oscillations on the HV power lines. Intelligent impedance injection modules (IIMs) are currently being proposed for interactive power line control and line balancing. These IIMs distributed over the high-voltage lines or installed on mobile platforms and connected to the HV power lines locally generate and inject waveforms in an intelligent fashion to provide interactive response capability to commands from utility for power line control.

Abstract: A clamping circuit employs a filter comprising two series branches of surge arresting circuits to clamp voltage spikes on equipment in series with a power transmission line. Clamping of these voltage spikes protects insulators, semiconductors, and other sensitive components within the series equipment from transient grid events. By using a predetermined frequency to control the response, the filter does not interfere with normal operation of the power system nor the operation of a power flow control module series-coupled to the transmission line through the filter. The clamping circuit employs hysteresis and imposes a shared voltage ratio between the two circuit branches, the ratio depending on frequency and voltage of the transient asserted on the transmission line, in order to provide a very sharp protection response to events within the target frequency range.

Abstract: A capacitor bank assembly has a conductive mount tray and capacitors. The capacitors are vertically mounted and held by the conductive mount tray. All positive terminals of the capacitors are connected to a first conductive plate. All negative terminals of the capacitors are connected to a second conductive plate. An insulating material separates the first conductive plate and the second conductive plate.

Abstract: A system and method for bi-directional direct current (DC) charging in electric vehicle supply equipment (EVSE) is disclosed. The system receives from power source managing subsystem, via plurality of power sources, electricity inputs corresponding to at least one of variable DC electricity input and relatively fixed DC input voltage comprising plurality of wide DC input voltage ranges. The system displays, via user interface associated with EVSE, selectable options to user. Further, system determines at least one of charging schema for charging operation, appropriate charging mode in plurality of charging modes, and discharging schema for the discharging operation using at least one of artificial intelligence (AI) techniques and machine learning (ML) techniques, based on power source information, and power demands. Further, the system executes, upon receiving the generated DC electricity, at least one of charging operation, appropriate charging mode, and discharging operation, based on power demands.

Abstract: An impedance injection unit (IIU) system is coupled to a high-voltage (HV) transmission line. The IIUs are activated in sequences of activation in successive time periods. This injects an impedance waveform onto the HV transmission line. The ordering of IIUs in the sequences of activation is repeatedly changed in successive time periods. This equalizes electrical stress across the IIUs used, leading to overall improvement in IIU system lifetimes.

Abstract: A control module controls impedance injection units (IIUs) to form multiple connection configurations in sequence. Each connection configuration has one IIU, or multiple IIUs in series, parallel or combination of series and parallel. The connection configurations of IIUs are coupled to a high-voltage transmission line. The control module and the IIUs generate rectangular impedance injection waveforms. When the waveforms are combined and injected to the high-voltage transmission line, this produces a pseudo-sinusoidal waveform.

Abstract: A voltage source converter has a first inverter valve unit that has a first terminal and a second terminal, and a second inverter valve unit that has a first terminal and a second terminal. The first inverter valve unit and the second inverter valve unit are connectedly arranged in parallel. The first inverter valve unit and the second inverter valve unit are self-balancing through equal capacitance and parallel connection of the first inverter valve unit and the second valve unit.

Abstract: A method and an apparatus for starting single-phase induction motors (SPIM) is disclosed. The apparatus use a rectifier and a DC-AC power converter, to replace the capacitor required in the startup of SPIM, providing high starting torque and eliminating stator overcurrents. The system uses a contactor to connect the SPIM directly to the AC voltage source once the nominal speed is reached. The disclosed method uses synchronization techniques to assure seamless transition of the SPIM from the power converter to the AC voltage source.

Abstract: The presence of injected DC has harmful consequences for a power grid system. A piecewise sinusoidal ripple voltage wave at the line-frequency that rides on the main capacitor bank of the power converter is observed. This observation leads to a new detection method and mitigation method. A two-stage control circuit is added to the operation of a power converter that controls power line impedance in order to mitigate the injected DC and to block DC circulation. This control computes a correction angle to adjust the timing of generated pulsed square waves to counter-balance the ripple. A functional solution and the results of experiments are presented. Furthermore, an extraction method and three elimination methods for this ripple component are presented to allow dissipation of DC energy through heat and/or electronic magnetic wave, or to allow transformation of this energy into usable power that is fed back into the power grid.

Abstract: Systems and methods of detecting non-uniform aging and degradation of power assembly units are disclosed. The system may include a first power assembly unit and a second power assembly unit adjacent to the first power assembly unit. Each of the first and second power assembly units has a coupling capacitor and a number of electrical components. The system may further include a current sensor in between the coupling capacitors of the first and second power assembly units to detect a current spike in the coupling capacitors and the electrical components.

Abstract: A control module controls impedance injection units (IIUs) to form multiple connection configurations in sequence. Each connection configuration has one IIU, or multiple IIUs in series, parallel or combination of series and parallel. The connection configurations of IIUs are coupled to a high-voltage transmission line. The control module and the IIUs generate rectangular impedance injection waveforms. When the waveforms are combined and injected to the high-voltage transmission line, this produces a pseudo-sinusoidal waveform.

Abstract: A control module controls impedance injection units (IIUs) to form multiple connection configurations in sequence. Each connection configuration has one IIU, or multiple IIUs in series, parallel or combination of series and parallel. The connection configurations of IIUs are coupled to a high-voltage transmission line. The control module and the IIUs generate rectangular impedance injection waveforms. When the waveforms are combined and injected to the high-voltage transmission line, this produces a pseudo-sinusoidal waveform.

Abstract: A method for synchronized injection of impedance into high voltage (HV) transmission line is disclosed. The method includes generating, by a plurality of impedance injection units (IIUs) coupled to the HV transmission line, impedance injection waves that cumulatively form a pseudo-sinusoidal wave. The method further includes optimizing, by the plurality of IIUs, the pseudo-sinusoidal wave to represent a pure sinusoidal wave. The method further includes injecting, by the plurality of IIUs, the pseudo-sinusoidal wave, as impedance, into the HV transmission line. The plurality of IIUs form multiple connection configurations in sequence, each connection configuration comprising one IIU or multiple IIUs in series, parallel or combination thereof, coupled to the HV transmission line.

Abstract: A power flow control unit has one or more impedance injection units. The impedance injection unit has high current drivers and capacitors forming a capacitor bank, and a cooling plate. The cooling plate is thermally coupled to the high current drivers and thermally decoupled from the capacitor bank. Bus bars connect the impedance injection units in series with a power transmission line. The power flow control unit is configurable to inject into the power transmission line a reactive power of at least one MVAr (mega volt-ampere reactive).

Abstract: A method for synchronized injection of impedance into high voltage (HV) transmission line is disclosed. The method includes generating, by a plurality of impedance injection units (IIUs) coupled to the HV transmission line, impedance injection waves that cumulatively form a pseudo-sinusoidal wave. The method further includes optimizing, by the plurality of IIUs, the pseudo-sinusoidal wave to represent a pure sinusoidal wave. The method further includes injecting, by the plurality of IIUs, the pseudo-sinusoidal wave, as impedance, into the HV transmission line. The plurality of IIUs form multiple connection configurations in sequence, each connection configuration comprising one IIU or multiple IIUs in series, parallel or combination thereof, coupled to the HV transmission line.

Abstract: A system and method using thyristors to protect a series-connected Flexible AC Transmission Systems (FACTS) device from surge currents are disclosed. According to some embodiments, the system includes a thyristor connected in shunt with the FACTS device to be protected. The system further includes control circuitry coupled to the thyristor to drive a gate of the thyristor with a direct current (DC) signal and turn on the thyristor in a time span on order of microseconds. The system and method can be used to protect any series-connected FACTS device that is in danger of being exposed to surge current such as a reclose after a deadline.

Abstract: The presence of injected DC has harmful consequences for a power grid system. A piecewise sinusoidal ripple voltage wave at the line-frequency that rides on the main capacitor bank of the power converter is observed. This observation leads to a new DC detection elimination method. Three DC elimination methods for this ripple component are disclosed to allow dissipation of DC energy through heat and/or electromagnetic wave, or to allow transformation of this energy into usable power that is fed back into the power grid.

Abstract: A system and method using four switches connected in an H-bridge (full bridge) topology within a series-connected FACTS device is disclosed. System and method can be used to bypass a FACTS device. The switches in H-bridge are connected to an alternating current (AC) source allowing for various switching states, and enabling non-monitoring mode, local bypass monitoring mode, low-loss monitoring mode, and diagnostic mode of operation.

Abstract: An impedance injection unit (IIU) system is coupled to a high-voltage (HV) transmission line. The IIUs are activated in sequences of activation in successive time periods. This injects an impedance waveform onto the HV transmission line. The ordering of IIUs in the sequences of activation is repeatedly changed in successive time periods. This equalizes electrical stress across the IIUs used, leading to overall improvement in IIU system lifetimes.

Abstract: In prior art grid systems, power-line control is done by substation based large systems that use high-voltage (HV) circuits to get injectable impedance waveforms that can create oscillations on the HV power lines. Intelligent impedance injection modules (IIMs) are currently being proposed for interactive power line control and line balancing. These IIMs distributed over the high-voltage lines or installed on mobile platforms and connected to the HV power lines locally generate and inject waveforms in an intelligent fashion to provide interactive response capability to commands from utility for power line control.