64results about "Reversal of power transmission direction" patented technology

A system having input terminals including line and neutral terminals for receiving AC power from a first AC source and having output terminals including output line and neutral terminals for receiving AC power from output terminals of a second AC source and for supplying AC power to a load, has a transfer switch configurable to connect the input terminals to the output terminals or to isolate the input terminals from the output terminals. When the transfer switch is configured to isolate the output terminals from the input terminals, the second AC source is caused to cease supplying power to the output terminals when after phase shifting the voltage produced by the second source the voltage at the input terminals is in-phase with that voltage.

The invention discloses a parallel connection protection circuit for a solar module, which comprises a field effect transistor, a driving module and a protection module, wherein the field effect transistor is used for reverse current limiting; the driving module is used for driving the field effect transistor; the protection module is used for preventing the gate of the field effect transistor from high-voltage breakdown; the driving module is connected with the protection module to form a control module of the parallel connection protection circuit which is connected in parallel with the anode and cathode of the output of the solar module; the gate of the field effect transistor is connected between the driving module and the protection module, the source of the field effect transistor is connected with the cathode of the solar module, and the drain of the field effect transistor is forms the anode and cathode of the output of the protected solar module with the anode of the solar module; and the protection module may be a resistor, a diode string, a voltage stabilizing diode or the like. The novel parallel connection protection circuit provided by the invention greatly reduces the loss of a solar module protection circuit, improves the power generating capacity of a solar cell in the morning, in the evening and in cloudy and rainy days, is simply structured, highly universaland low in cost, and can promote the popularization of solar energy application.

An embodiment high efficiency power regulator comprises a three-terminal converter and a protection device. The three-terminal converter comprises a first terminal coupled to a positive terminal of an input voltage bus, a second terminal coupled to a positive terminal of an output voltage bus and a third terminal coupled to the protection device. The protection device comprises an inrush current limiting element connected in series with a reverse polarity protection device.

A protection circuit includes a power supply terminal, a ground terminal, a control unit connected to the power supply terminal and the ground terminal, and a supply unit connected to the power supply terminal and the ground terminal, for preventing application of voltage in a reverse direction to a circuit unit having a predetermined function. In this case, the control unit generates a control potential, which controls the control unit and the supply unit in accordance with a potential supplied from the power supply terminal and a potential supplied from the ground terminal. The supply unit is configured to be capable of supplying current to a circuit unit connected to a subsequent stage on the basis of a potential supplied from the power supply terminal, a potential supplied from the ground terminal, and the control potential generated by the control unit.

A control system and method for sectionalizing switches and pulse-testing interrupter / reclosers in a distribution grid feeder which enables fault location, isolation and service restoration without requiring an external communications infrastructure to pass information between the switches. The method includes switches entering an armed state when they experience a high fault current during an initial fault event. Then, when the interrupter / recloser runs its test pulse sequence, any armed switch counts all test pulses as fault pulses, while non-armed switches count the test pulses as load pulses. Switches open to isolate the fault based on threshold values of fault pulse count and load pulse count. When an initially active interrupter / recloser completes its test pulse sequence, another interrupter / recloser begins its sequence, and all switches reconfigure their threshold values based on the new interrupter / recloser. Interrupter / reclosers after the initial device use a fast close-open event if necessary to arm some switches for proper fault-count opening.

An overvoltage clipping device for clipping an overvoltage occurring at a main transformer of a wind turbine is provided. The overvoltage clipping device includes a detection unit for detecting an actual voltage level at the main transformer. The determination unit which is operatively connected to the detection unit determines whether the actual voltage level is above a predetermined reference voltage level. At least one switching unit is provided which is operatively connected to the determination unit for electrically coupling at least two transformer terminals of the main transformer. The control unit drives the switching unit if the detected actual voltage level is above the predetermined reference voltage level such that the at least two transformer terminals are electrically coupled to each other by the switching unit.

A device includes a first thyristor element configured to be coupled to a first voltage line and a second voltage line, wherein the first voltage line is configured to transmit power in a first phase and the second voltage line is configured to transmit power in a second phase. The device includes a second thyristor element configured to be coupled to the second voltage line and a third voltage line, wherein the third voltage line is configured to transmit power in a third phase. The device includes a third thyristor element configured to be coupled to the first voltage line and the third voltage line.