Abstract: Primary protection relays and an integrator disclosed for providing primary protection and secondary applications for an electric power delivery system. The primary protection relays obtain signals from, and provide primary protection operations for the power system, and may operate independently from the integrator. An integrator receives signals and status communications from the primary protection relays to perform secondary applications for the electric power delivery system. The secondary applications may include backup protection, system protection, interconnected protection, and automation functions.

Abstract: A method for controlling a power distribution network includes receiving, by an electronic processor, a fault indication associated with a fault in the power distribution network from a first isolation device of a plurality of isolation devices. The processor identifies a first subset of a plurality of phases associated with the fault indication and a second subset of the plurality of phases not associated with the fault indication. The first and second subsets each include at least one member. The processor identifies an upstream isolation device upstream of the fault. The processor identifies a downstream isolation device downstream of the fault. The processor sends an open command to the downstream isolation device for each phase in the first subset. Responsive to the first isolation device not being the upstream isolation device, the processor sends a close command to the first isolation device for each phase in the first subset.

Abstract: A load drive circuit includes a power source terminal (“PST”), a power source and a load terminal connecting a load to the power source. A semiconductor switch connects the PST to the load terminal. A control circuit includes an output terminal for opening/closing the semiconductor switch. A freewheeling circuit includes a freewheeling diode and a protection switch blocks a current from the power source to the semiconductor switch when the power source is connected in a reverse manner. A first terminal connects the control circuit to a first fixed potential and a second terminal connects an anode of the freewheeling diode to a second fixed potential. A connection circuit includes a connection switch connecting the output terminal and the first terminal. The connection circuit connects the output terminal to the first terminal when a rise in a potential difference between the first terminal and the second terminal is detected.

Abstract: A display system is disclosed. The display system includes an electronic device including first and second interfaces and a display apparatus. The electronic device is configured to: rectify external alternating current (AC) power by direct current (DC) power based on a first ground, convert the DC power into power based on a second ground, provide the converted power to the display apparatus through a first interface connected to the second ground, and provide a signal received from an external device through a second interface connected to an earth ground to the display apparatus through the first interface, wherein a ground of the display apparatus is the same as the second ground and the second ground is different from the earth ground.

Abstract: A DI-circuit breaker device includes a summation current converter for detecting fault currents in a phase conductor and a neutral conductor, and a detection device for detecting fault states of a protective ground conductor. The detection device detects the presence of a phase voltage on the protective ground conductor as a fault state. The detection device has a capacitive sensor which, when touched by a user, forms an electric capacitor with an impedance relative to ground potential. The detection device further has evaluating electronics adapted to determine a phase position by connecting the sensor to the phase conductor and, separately therefrom, to the neutral conductor. The evaluating electronics determine the absence of a phase voltage on the protective ground conductor when there is no voltage between the neutral conductor and the protective ground conductor when phase is present at the phase conductor. Further, a corresponding operating method is described.

Abstract: A DC-DC converter includes an input voltage source in series with a parasitic capacitance. The voltage changes and causes resonant ringing, wherein the input voltage source is connected to a rectifier means which is connected to an output circuit. A passive clamp circuit across the rectifier means includes a clamp diode, a clamp capacitor, and an auxiliary circuit. The auxiliary circuit includes first and second rectifiers in series with an electronic component having first and second terminals. The first rectifier has an anode connected with the passive clamp circuit, and a cathode connected to the second terminal of the electronic component. The second rectifier has a cathode connected with the anode of the first rectifier, and an anode connected with the first terminal of the electronic component. Some of the leakage inductance transfers to an auxiliary energy storage and damps the resonant ringing.

Abstract: A thermal hazard protection circuit for a transportation vehicle comprises an interruptible power circuit connected between a power source and load, and a failsafe circuit operative to permanently interrupt current flow under an overcurrent condition. The interruptible power circuit comprises a Positive Temperature Coefficient (PTC) component in series with bi-stable relay configured as a SPST switch. The failsafe circuit comprises a failsafe relay energized by current in the interruptible power circuit. An input of the failsafe relay is connected to the power source, and a normally closed (NC) output (not connected to the input so long as the failsafe relay is energized) is connected to a control input of the bi-stable relay that opens the SPST switch. In an overcurrent condition, the PTC component limits current flow, switching the failsafe relay input to its NC outputs, providing a control signal to open the SPST switch, rendering the interruptible power circuit non-conductive and isolating the load.

Abstract: A DC voltage coordination control method is applied to a multi-terminal VSC-HVDC power transmission system or a VSC-HVDC power grid system. When a lower-level control is used in the active power control mode, the active power reference value of the converter is generated according to the converter DC voltage and the converter DC voltage active power curve; it also includes an upper-level control to adjust the control mode and active power setting value of the lower-level control to ensure the steady-state performance of the system. This method has low dependence on communication, avoids the problem that the fixed slope and margin cannot meet all operating conditions, and is suitable for large-scale VSC-HVDC systems, and has scalability.

Abstract: Provided is a method of supplying at least one component of a wind turbine with energy. The energy during operation of the wind turbine is taken from energy generated using a generator of the wind turbine and provided for supply to the at least one component of the wind turbine. Provided is an energy supply device for performing the method and a wind turbine having the energy supply device.

Abstract: A voltage monitoring circuit portion is arranged to monitor a negative supply voltage (Vneg) and comprises a negative voltage generator arranged to generate the negative supply voltage (Vneg) and to output the negative supply voltage (Vneg) at an output terminal. A capacitor is arranged so that a first capacitor plate is connected to the output terminal of the generator and to a reference node via a potential divider. The potential divider is arranged to produce a monitor voltage (Vmonitor) between the resistors, where the reference node is supplied with a positive predetermined reference voltage (Vref). A comparator compares the monitor voltage (Vmonitor) to a threshold voltage (Vref_low) and to produce an output signal having a first value when the monitor voltage (Vmonitor) is below the threshold voltage (Vref_low) and having a second value otherwise. The negative voltage generator is enabled only when the output signal has its second value.

Abstract: A method of controlling an isolated switching converter having an output voltage that is adjustable, can include: generating an output voltage setting signal characterizing an expected output voltage of a load; increasing a time period when an output voltage reference signal changes from a current value to the output voltage setting signal; and making overvoltage protection not trigger due to a change of the output setting signal.

Abstract: An in-vehicle power control system includes a first load control unit and a power control device. In the power control device, switch units respectively switch the second conductive paths between an electrically connected state and a not-electrically connected state. A second load control unit predetermines types of switch units, and, if the second load control unit has received, from the first load control unit, a power reduction instruction in which a control method is designated by type, controls the switch units for each type thereof based on the control methods designated by type by the power reduction instruction.

Abstract: A device for detecting a drop in voltage of an AC supply delivering electrical energy to an energy converter in order to supply electrical equipment, the device being connected to an electrical energy reserve for supplying the energy converter. The device includes a full-wave rectifier for rectifying the AC supply, a comparator that compares a first predetermined voltage with a full-wave rectified voltage, a circuit for charging a capacitor in order to charge the capacitor when the rectified voltage is below the predetermined threshold, a circuit for discharging the capacitor in order to discharge the capacitor when the rectified voltage is above the predetermined threshold, a comparator for comparing the voltage at the terminals of the capacitor with a second predetermined voltage, and a circuit for controlling the reserve of electrical energy.

Abstract: A method for identifying type of a grid automatically and an inverter device thereof are provided. The inverter device comprises a power line L1, a power line L2, a neutral line N and a ground line electrically connectable to a first power line, a second power line, a neutral line and a ground line of the grid, respectively. The method comprises: sampling at least two of voltages between L1 and L2, between L1 to N and between L2 to N when the two neutral lines are connected, and identifying the type of the grid based on the sampling result; and sampling the voltage between L1 and L2 when the two neutral lines are not connected, sampling at least one of a voltage between L1 and GND and between L2 and GND with cooperation of a grid-connected switching unit, and identifying the type of the grid based on the sampling results.

Abstract: A drive module for use in a switching power supply generating output voltage from input voltage by turning on/off an output transistor and a synchronous rectification transistor includes: a zero-cross detection circuit detecting zero-cross of inductor current flowing when the synchronous rectification transistor is turned on; a drive logic circuit turning on the output transistor and turning off the synchronous rectification transistor when control signal is at first logic level, turning off the output transistor and turning on the synchronous rectification transistor when the control signal is at second logic level, and turning off both the output transistor and the synchronous rectification transistor when the zero-cross is detected; and a logic level switching circuit switching the control signal to third logic level when the zero-cross is detected, wherein the zero-cross detection circuit, the drive logic circuit, and the logic level switching circuit are integrated in a single package.

Abstract: A method includes providing a transformer with primary and current injection windings, a primary switch connected to the primary winding, a parasitic capacitance reflected across the primary switch, a secondary rectifier means, and a current injection circuit including a current injection switch connected to the current injection winding, and a unidirectional current injection switch connected to the current injection winding. The method includes switching on the current injection switch to start a current injection flowing from a controlled voltage source, through the unidirectional current injection switch and further through the current injection winding. The current injection reflects into the primary winding, thereby discharging the parasitic capacitance reflected across the primary switch. The method includes turning on the primary switch with a delay time after the current injection switch turns on and turning off the current injection switch after the current injection reaches zero amplitude.

Abstract: A method and a device for detecting faults and for protection of electrical networks, the electrical networks being fed from a transformer station through a first three-phase switching device with circuit breaker, a distribution network and feeders. A second three-phase switching device with circuit breaker is connected before the feeders. The circuit breaker of the second switching device, has parallel-coupled damping impedances and is connected in series between the first three-phase switching device and the feeders when a short circuit current is detected. At least one of the damping impedances has deviating properties compared to the others, so as to create a negative sequence current detectable in the electrical networks. The damping impedances are bypassed by the circuit breaker of the second switching device after a predetermined period of time.

Abstract: A power supply system includes: a semiconductor switch (1) that is turned on at the time of normal supply from a commercial AC power supply (5); a first current detector (CT1) including a transformer (10) and configured to detect an AC input current (I1); a second current detector (CT2) including a Hall effect sensor (20) and configured to detect an AC output current (I2); and a failure detector (30) that determines that one of a pair of thyristors (1a, 1b) included in the semiconductor switch (1) has misfired when the detection values from the first and second current detectors (CT1, CT2) are not equal at the time of normal supply from the commercial AC power supply (5).

Abstract: A wall for an electrical equipment enclosure includes an outer panel, an inner panel having a first side facing a chamber of the enclosure and a second side facing the outer panel, and at least one flange spaced apart from the outer panel and facing at least one peripheral portion of the inner panel and configured to prevent movement of the at least one peripheral portion of the inner panel towards the outer panel. The first panel is configured to press the at least one peripheral portion against the at least one flange responsive to pressure generated by an arc flash to form a seal between a periphery of the inner panel and the at least one flange that impedes passage of arc flash gases.

Abstract: An arrangement for reactive power compensation at an electric energy transmission line includes at least one first reactive power compensation device including a first type of power electronic switches, at least one second reactive power compensation device including a second type of power electronic switches and a transformer having a first secondary coil connected to the first device, a second secondary coil connected to the second device and a primary coil connectable to the electric energy transmission line. The primary coil has more windings than any of the first and second secondary coils.