Abstract: An electrical power system including: an electrical power source, a power electronics converter, an electrical network, a current limiting diode and a controllable circuit interruption device, wherein: the current limiting diode is configured to limit a fault current passing between the electrical power source and the electrical network in a fault condition; and the controllable circuit interruption device is configured to interrupt the fault current in response to a determination that the electrical power system is in the fault condition.

Abstract: A current detection circuit capable of compensating for detection accuracy of a switching current through switching of a connection state of a resistor even when the switching current has a component in a direction opposite to a predetermined direction is provided. A current detection circuit for detecting a value of a component in a predetermined direction of a switching current using a current transformer, wherein, when the switching current flowing in a primary side of the current transformer has a component in a direction opposite to the predetermined direction, a connection state of reset elements on a secondary side of the current transformer is switched such that an impedance of a magnetic reset on the secondary side of the current transformer is decreased.

Abstract: The invention relates to a battery (100) that works by regulating the power source (112) to provide a suitable voltage output so that the user's devices/products using the battery will have a high performance among several other advantages. The battery (100) comprises a positive terminal (102); a negative terminal (112); a power source (114); and a voltage regulation device (110). The voltage regulation device (110) is operatively connected to the positive terminal (102), the negative terminal (112) and the power source (114). The voltage regulation device (110) includes electronic components that are operatively connected to each other in order to regulate an output voltage in a programmed variable level.

Abstract: A semiconductor circuit has a primary circuit that causes the light emitting element to emit light in accordance with a current flowing through a control target, and that causes the light emitting element to emit light brighter when an overcurrent flows through the control target; and a secondary circuit that is electrically insulated from the primary circuit, outputs a voltage according to a light emission amount of the light emitting element, and outputs an overcurrent detection signal indicating the brighter light emission in the light emitting element.

Abstract: A re-configurable bank of DC-DC converters has many channels, each with a DC-DC converter and a controller that senses the channel's output voltage and current to adjust a duty cycle of switch signals to the DC-DC converter. A serial bus connects to all controllers and writes digital voltage and current control targets into each controller. The controller has Digital-to-Analog Converters (DACs) that convert the targets to analog voltages that are compared to sensed output voltage and current. The comparison results are compared to a sawtooth wave to generate pulses of the switch signals that have a duty cycle adjusted for the target comparisons. In combined mode, a primary channel's controller generates switch signals for secondary channels having outputs shorted to the primary channel. Secondary channels have a mux to select switch signals from the primary controller during combined mode, and from the secondary controller during separated mode.

Abstract: A control unit of an electrical system is described. The control unit causes some of the switches in a power converter of the electrical system to not be shut down and not conducting upon detection of a fault current caused by a line-to-line fault. Instead, the control unit causes at least one of the switches to be switched-on and conducting to allow the some of the fault current to flow through the at least one switch, before activating a protection device that creates an open circuit and breaks the fault.

Abstract: A system and method for detection of a fault in a component of an Alternate Current Motor (ACM) based on current samples of the ACM. The system includes a current sensor for sampling a current of the ACM. The sampling is performed a plurality of times within a half-wave form of an Alternate Current (AC) of the ACM and over several cycles of half-waves. The system also includes a computing device for receiving the plurality of current samples. The computing device is configured to analyze a plurality of current samples of the AC of the ACM, the plurality of current samples taken for at least several periods of half-waves of the AC, determine, based on the analysis of the plurality of current samples, whether the ACM is a Variable Frequency Drive (VFD) or a non-VFD, and report that fault detection cannot be made if the ACM is a VFD.

Abstract: A power module includes a plurality of power semiconductor devices. The plurality of power semiconductor devices includes an insulated gate bipolar transistor (IGBT) and a metal-oxide-semiconductor field-effect transistor (MOSFET) coupled in parallel between a first power switching terminal and a second power switching terminal. The IGBT and the MOSFET are silicon carbide devices. By providing the IGBT and the MOSFET together, a tradeoff between forward conduction current and reverse conduction current of the power module, the efficiency, and the specific current rating of the power module may be improved. Further, providing the IGBT and the MOSFET as silicon carbide devices may significantly improve the performance of the power module.

Abstract: Disclosed is a power conversion device having an AC conversion unit and a control unit that controls the AC conversion unit. The power conversion device also has: a temperature detection unit that outputs temperature data of the power conversion device; a current detection unit that outputs current data of an output of the AC conversion unit; a storage unit that stores specification data indicating a relationship between a rated current and a temperature specification and temperature data output by the detection unit; an overload protection unit that outputs a shutdown command to the control unit on the basis of the rated current and the current data output by the current detection unit; and a rating determination unit that acquires specification data and temperature data from the storage unit, determines a rated current corresponding to the acquired temperature data on the basis of the acquired specification data, and outputs the determined rated current to the overload protection unit.

Abstract: Provided is an electric control unit which is configured to switch the functions of an LCC, an HSD, and an LSD depending on a load to be connected. A power-supply-side switching element 102 is provided in a path L1 between a power supply 401 and a connector terminal 301. A ground-side switching element 106 is provided in a path L2 between a ground 402 and a connector terminal 302. A freewheeling diode 105 is provided in a path L3 connected to a connection point P1 between the power-supply-side switching element 102 and the connector terminal 301 and a connection point P2 between the ground-side switching element 106 and the connector terminal 302. A switching element 104 is provided in the path L3.

Abstract: A motor drive apparatus includes an inverter configured to convert an input DC voltage into an AC voltage for driving a motor, by ON/OFF driving of an internal power element, and outputs the AC voltage, a high-frequency current detection unit configured to detect a high-frequency current from a current flowing through a motor power line upon application of the AC voltage output from the inverter to the motor via the motor power line, and a stray capacitance estimation unit configured to estimate a stray capacitance occurring in the motor power line and the motor, based on the high-frequency current detected by the high-frequency current detection unit.

Abstract: A modular multilevel converter (MMC) converter including an auxiliary sub-module provided between an upper converter arm and a lower converter arm of the MMC converter is provided. An MMC converter includes an auxiliary sub-module including: an energy storage unit storing a DC voltage in the sub-module; a first semiconductor switch connected to the energy storage unit; a second semiconductor switch connected to the first semiconductor switch; a third semiconductor switch connected to the second semiconductor switch; and a switching controller turning ON/OFF the first to third semiconductor switches, wherein a mid-point between the first and second semiconductor switches is connected to the sub-module of the upper converter arm, a mid-point between the second and third semiconductor switches is connected to a load connection terminal, and a mid-point between the third semiconductor switch and the energy storage unit is connected to the sub-module of the lower converter arm.

Abstract: A power control apparatus according to the present disclosure includes a first interconnection relay and a second interconnection relay configured to interconnect or parallel off an inverter to or from a power grid, a reference potential relay configured to set a neutral phase of an independent operation output system to a reference potential, voltage sensors respectively installed between the first interconnection relay and the inverter and between the first interconnection relay and the power grid, voltage sensors respectively installed between the second interconnection relay and the inverter and between the second interconnection relay and the power grid, and a controller configured to turn the reference potential relay on to set the neutral phase to the reference potential and then to judge whether a state of each interconnection relay is normal on the basis of voltage values measured by the voltage sensors.

Abstract: An inverter apparatus with overcurrent protection control includes a first terminal of a DC input terminal connected to an AC output terminal through a first switch element and a second switch element, and a second terminal of the DC input terminal connected to the AC output terminal through a fourth switch element and a third switch element. An intermediate potential terminal is connected to a fifth switch element and a sixth switch element, and connected to the AC output terminal through the fifth switch element and the second switch element, and connected to the AC output terminal through the sixth switch element and the third switch element. When the control unit determines that the inverter apparatus is in an overcurrent state, the control unit controls a sequence of turning off the inverter apparatus to be the second switch element, the first switch element, and the sixth switch element.

Abstract: A voltage source converter based DC deicer and its control method are provided. The voltage source converter based DC deicer includes a connecting reactor, a modular multilevel voltage source converter based on a full H-bridge submodule, smoothing reactors, deicing disconnectors, a deicing bus, and a deicing AC line. The AC side of the modular multilevel voltage source converter is connected to an AC side bus through the connecting reactor, an isolation disconnector and a breaker. The DC side of the modular multilevel voltage source converter is connected to the deicing AC line through the smoothing reactors, the deicing disconnectors, and the deicing bus.

Abstract: A current sensorless control system and a control method thereof for single stage isolated PFC converters based on DAB. By coordinating three control variables of the DAB converter, that is, the inside phase-shifting ratio of the primary side full-bridge, the inside phase-shifting ratio of the secondary side full-bridge, and the phase-shifting ratio between the primary and the secondary sides, the present invention does not need to design additional current controller for the control of the input current, and may make the input current sinusoidal by directly coordinating the output voltage controller, the input voltage and the current modulation step, thereby reducing system cost and the difficulty of controller design, enhancing the stability of the control system, and improving the dynamic performance.

Abstract: One feature pertains to an apparatus that includes a first stage track and hold circuit that subsamples a receive equalizer output of a receive equalizer, and a second stage track and hold circuit that generates a first signal representative of an average voltage value of a logical value at the receive equalizer output when a high frequency bit pattern is detected, and a second signal representative of an average voltage value of the logical value at the receive equalizer output when a steady state bit pattern is detected. The apparatus further includes a comparator circuit that generates a comparator output signal that indicates which of the first signal and the second signal has a greater magnitude, and a processing circuit that generates equalizer tuning signals based on the comparator output signal to adjust parameters of an equalizer that affects the receive equalizer output.

Abstract: Various methods and devices that involve snubber circuits for switching power converters are disclosed. An example power converter has a snubbing circuit. The snubber circuit comprises a bypass capacitor connecting an input node of the power converter to a ground node of the power converter, a decoupling capacitor that connects the input node of the power converter to a snubber node, and a snubbing resistor that connects the snubber node to the ground node. The snubbing resistor connects the decoupling capacitor to the ground node of the power converter. The snubbing resistor is greater than 1 ohm. The decoupling capacitor is greater than 5 nanofarads and less than 0.5 microfarads. The bypass capacitor is greater than 1 microfarads.

Abstract: An electronic device has a power semiconductor device, a first semiconductor integrated circuit device, and a second semiconductor integrated circuit device. The power semiconductor device has a terminal outputting sense current. The first semiconductor integrated circuit device has an overcurrent detection circuit detecting overcurrent on the basis of the sense current, and a temperature detection circuit detecting temperature of the power semiconductor device. The second semiconductor integrated circuit device has a storage device storing a temperature characteristic of a current mirror ratio of the power semiconductor device, a temperature detecting unit calculating temperature on the basis of an output of the temperature detection circuit, and an overcurrent detection control unit controlling the overcurrent detection circuit on the basis of the temperature detected by the temperature detecting unit and the temperature characteristic of the current mirror ratio stored in the storage device.

Abstract: A method for operating an inverter, the DC voltage input of which is connected to a positive pole (PV+) and to a negative pole (PV?) of a PV generator and the AC voltage output of which is connected to an AC grid via a transformer, is disclosed. The method includes determining a potential of the positive pole and/or the negative pole (UPV+, UPV?) of the PV generator with respect to a ground potential by a monitoring circuit, and selecting a modulation method for controlling power switches of the inverter from a number of modulation methods stored in a storage device of the inverter based on the determined potential (UPV+, UPV?) such that a voltage stress on components of the PV system arranged on the AC side, with respect to ground, is reduced. The method further includes using the selected modulation method to control the power switches for the purpose of converting a DC input voltage into an AC output voltage.

Abstract: In the field of high voltage direct current power transmission networks, a voltage source converter comprises first and second DC terminals for connection to a DC electrical network, and a plurality of single-phase limbs. Each single-phase limb includes a phase element, and each phase element includes at least one switching element configured to interconnect a DC voltage and an AC voltage. An AC side of each phase element is connectable to a respective phase of a multi-phase AC electrical network, and each single-phase limb is connected between the first and second DC terminals. The voltage source converter further comprises a controller configured to determine independently of one another an amount of active power (Pref) that the voltage source converter should exchange with the AC electrical network and an amount of reactive power (Qref) that the voltage source converter should exchange with the AC electrical network.

Abstract: A chiller system (200) includes a motor (212), a motor controller (214) connected to the motor (212), the motor controller (214) operative to send a control signal to the motor (212), a rectifier (206) connected to an alternating current (AC) power source (204), the rectifier (206) operative to receive AC power and output direct current (DC) power, a DC bus (208) connected to the rectifier (206), a first inverter (210) connected to the DC bus (208) and the motor (212), the first inverter (210) operative to receive DC power from the DC bus (208) and output AC power to the motor (212), and a second inverter (213) connected to the DC bus (208) operative to receive DC power and output AC power to the motor controller (214).

Abstract: A circuit assembly for discharging an electrical energy store includes a first discharge current path for uncontrolled, passive discharging of the energy store and for keeping a defined charge voltage of the energy store, and a second discharge current path for controlled, active discharging of the energy store. A semiconductor switch electrically connects to a positive current connection of the energy store and to a negative current connection of the energy store. A voltage limiter includes a first current connection for electrically connecting to the positive current connection of the energy store and a second current connection for electrically connecting to the negative current connection of the energy store. The circuit assembly further includes a first control path for providing a first control signal from the first current connection of the voltage limiter to the control connection of the semiconductor switch in order to control the semiconductor switch.

Abstract: The invention relates to a control device (12) for actuating a pulse-controlled converter of an electric drive system, having: an open-loop/closed-loop control circuit (12a) which is configured to generate pulse-width-modulated actuation signals for switching devices of the pulse-controlled converter; a fault logic circuit (12b) which can detect fault states in the drive system and which is configured to select a switching state or a sequence of switching states for the switching devices of the pulse-controlled converter which are assigned to the corresponding fault state; and a protection circuit (12c) which is embodied in hardware and which comprises a signal delay device (15), which is configured to delay the actuation signals in order to implement a minimum protection time, and a locking device (16a, 16b) which is configured to lock two complementary switching devices of a bridge branch of the pulse-controlled converter with respect to one another.

Abstract: An inverter for driving a motor generator has series connection units, each of which has two switching elements, connected in series, in high and low voltage sides, respectively. A drive unit is arranged for each switching element. A gate of the switching element is connected to an emitter thereof through a first cutoff resistance and a first cutoff switching element in the drive unit. The gate of the switching element is also connected to the emitter thereof through a second cutoff resistance and a second cutoff switching element in the drive unit. A resistance value of the first cutoff resistance is higher than a resistance value of the second cutoff resistance. A software cutoff process is performed when the switching element is in a completely turned-on state so that the first cutoff switching element is turned on and the second cutoff switching element is turned off.

Abstract: The invention refers to a method for controlling a brushless, electronically commutated electric motor, a main AC voltage being rectified into an intermediate circuit direct voltage and this direct voltage being fed by an intermediate circuit containing an intermediate circuit capacitor to an inverter which is controlled by a motor control means for feeding and commutating the electric motor whereby the intermediate circuit direct voltage is monitored in respect of its voltage level and is compared with a predetermined limiting value and, on reaching or exceeding the limiting value, the intermediate circuit direct voltage is limited to the predetermined limiting value by clocked disconnection and reconnection.

Abstract: A converter valve unit including a plurality of parallel connected controllable semiconducting elements. A free-wheeling diode is connected in anti-parallel with each semiconducting element. A control unit is configured to control each semiconducting element. A current sensor is connected to each of the parallel connected semiconducting elements. The current sensor is configured to sense a current of each semiconducting element by measuring a voltage over the current sensor. A differentiator is configured to compare the currents of the semiconducting elements by comparing the voltages. Upon detecting an unbalance in the currents the differentiator sends a turn-on signal to all control units to control all the semiconducting elements of the valve unit into a conducting stage.

Abstract: The invention relates to an LED converter for operating a load comprising at least one LED series that includes at least one LED, preferably multiple LEDs. On the primary side, the LED converter comprises a resonant converter supplied with a direct current voltage. The resonant converter has a half-bridge that is constructed of two reciprocally clocked switches and that provides a supply voltage for the LED series through a serial/parallel resonance circuit connected to the midpoint of said half-bridge. To regulate the power transferred by the LED converter to the LED series as a feedback factor in each switch-on cycle, a control unit is designed to directly or indirectly determine a peak value of the feedback factor through the lower-potential switch of the half-bridge and to adjust the clocking of the half-bridge, i.e. the frequency and/or the duty factor, as a control factor.

Abstract: A method for operating an electrical power rectifier. The power rectifier comprises at least two branches that are connected in parallel to each other, each of the branches comprising at least two power semiconductor elements that are connected in series. The collector-emitter voltage Vce(t) and/or the collector current Ic(t) of one of the power semiconductor elements is detected by means of the method. Furthermore, it is determined whether at least one of the following conditions is met: dVce(t)/dt<(dVce/dt)crit, and/or dIc(t)/dt<(dIc/dt)crit, and or Ic(t_ent)<Iccrit. If at least one of the aforementioned conditions has been met, the gate-emitter voltage of at least one of the power semiconductor elements is increased.

Abstract: The invention relates to a method for operating an inverter (1), in particular a pulse-controlled inverter, comprising multiple phase systems (2, 3, 4), each of which has an outer conductor (7, 8, 9) and at least one semiconductor component (12, 13), and a temperature monitoring device (15) that has multiple temperature sensors (16, 17, 18) which sense the temperature of at least one part of at least one of the phase systems (2, 3, 4). In said method, a temperature gradient is determined from each of the sensed temperatures, the difference of the determined temperature gradients from each other is ascertained, and if the difference exceeds at least one threshold value, a fault of a cooling device of the inverter (1) is identified. The invention further relates to an inverter (1).

Abstract: A three-level power conversion circuit includes a plurality of one-phase switch circuits which receive power from direct current power supplies that are connected in series. Each of the one-phase switch circuits includes a semiconductor switch series circuit that is connected in parallel to the direct current power supplies, and also a bidirectional switch and a circuit-opening device that are connected in series between a series connection point of the semiconductor switch series circuit and a series connection point of the direct current power supplies. If a semiconductor element in a bidirectional switch fails, the circuit opening device opens a path along which the main current of the semiconductor element flows, and operation of the inverter is continued as a two-level inverter with the remaining bidirectional switches in a constant off-state.

Abstract: A semiconductor device includes a control section, a first arm, and a second arm; and has an H-bridge circuit to supply an input current supplied from a power source to an output terminal as a reversible electric current on the basis of a control signal outputted from the control section and a reverse-connection-time backflow prevention circuit to prevent an electric current in a direction opposite to the direction of the input current from being supplied to the H-bridge circuit. The first arm is formed over a first island. The second arm is formed over a second island. The control section and the reverse-connection-time backflow prevention circuit are formed over a third island.

Abstract: A current resonance power supply includes a current detecting unit detecting a current flowing through a primary side of a transformer and a current compensating unit compensating the current detected by the current detecting unit in accordance with a variation in voltage input into the primary side of the transformer. The current resonance power supply detects overcurrent on the basis of an output from the current compensating unit.

Abstract: A no load detection and shutdown circuit in an isolated driver is provided. A no load condition is detected by primary side evaluation of a reflected voltage. If a determination is made that a no load condition is present, the no load detection circuit signals a half bridge driver of the driver to cease oscillations, shutting down the driver.

Abstract: A power converter control device includes an alarm signal generation circuit which detects information necessary for a protection operation of a semiconductor element configuring a power converter, and generates and externally outputs an alarm signal with a pulse width responding to a protection factor; a temperature signal generation circuit which detects a temperature of the semiconductor element, and generates a PWM signal, correlated with the temperature, the cycle of which is different from the pulse width of the alarm signal; and an output control circuit which selects the PWM signal in normal time, and selects and externally outputs the alarm signal in place of the PWM signal when the alarm signal is generated.

Abstract: An apparatus and method for controlling an operation of an inverter are provided. In the inverter control apparatus, an operation signal input unit detects a current of each phase output from an inverter. An error detecting unit detects whether there is a fault of the inverter on the basis of the current detected by the operation signal input unit. A controller controls driving of the inverter according to a type of the fault detected by the error detecting unit. A storage unit stores a kind of fault of the inverter and a corresponding fault type on the basis of the current detected in the operation signal detecting unit.

Abstract: The control of an inductive load is implemented by a control strategy to generate a control signal for a switching element on the basis of a setpoint datum, with a mechanism defining a maximum permitted value (Imax) of the current in the load as a function of the temperature at the level of the switching element. The mechanism exhibits a temperature threshold (Tshd). The maximum permitted value (Imax) of the current is held constant, equal to an upper limit value (Isup), during a temperature climb phase for all the temperatures which are lower than the threshold. The maximum permitted value of the current is abruptly rendered equal to a lower limit value (Iinf) as soon as the temperature reaches the threshold. Finally, during a temperature descent phase, the maximum permitted value of the current gradually climbs back to the upper limit value as the temperature decreases.

Abstract: A protection circuit of a DC-DC converter is disclosed. An input terminal of the DC-DC converter receives an input voltage and an output terminal of the DC-DC converter provides an output voltage. The DC-DC converter includes an output stage between the input terminal and the output terminal. The protection circuit includes a current sensor, a comparator, a determining circuit, and a protection control circuit. The current sensor provides a sensing signal. The comparator compares a default over-voltage with the sensing signal to provide an over-current control signal. The determining circuit provides a determining control signal. The protection control circuit determines whether to enable a short protection according to the over-current control signal and the determining control signal.

Abstract: A control circuit performs at least one of detecting whether the resonance current detected by the current detection unit is beyond a first detection level over a predetermined time period, and detecting, when detecting that the resonance current is beyond the first detection level over the predetermined time period, that the resonance current falls below a second detection level, and detecting whether the resonance current detected by the current detection unit is below a first detection level over a predetermined time period, and detecting, when detecting that the resonance current is below the first detection level over the predetermined time period, that the resonance current exceeds a second detection level, and inverts, when detecting that the resonance current falls below or exceeds the second detection level, the levels of the drive control signal at which the first switching element and the second switching element are turned on or off.

Abstract: Example embodiments disclose a drive system including a machine including a plurality of phases and configured to generate power based on a plurality of phase currents, each respectively associated with the plurality of phases and a direct current (DC) bus, operatively connected to the machine. The DC bus includes a high-side line, a low-side line, and an inverter including a plurality of switching systems, operatively connected between the high-side line and the low-side line, the plurality of switching systems, each configured to output a respective one of the plurality of phase currents. The drive system also includes a controller, operatively connected to the DC bus and the machine, the controller configured to determine if a failure exists in the drive system based on the plurality of phase currents and a DC bus voltage, the DC bus voltage being a voltage across the high-side line and the low-side line.

Abstract: A power distribution system (that can detect an unsafe fault condition where an individual or object has come in contact with the power conductors) regulates the transfer of energy from a source to a load. Periodically, the source controller opens an S1 disconnect switch, a and load controller opens an S2 disconnect switch. A capacitor represents the capacitance across the load terminals. If the capacitor discharges at a rate higher or lower than predetermined values after the S1 and S2 disconnect switches are opened, then a fault condition is registered, and the S1 and S2 switches will not be commanded to return to a closed position, thus isolating the fault from both the source and the load.

Abstract: A semiconductor element drive device which individually drives semiconductor elements configuring a power converter includes plural protection circuits which detect information necessary for carrying out a protection operation for the semiconductor elements, an alarm signal output circuit which, having set therein pulse signals with pulse widths differing from one of the plural protection circuits to another, continuously outputs a pulse signal corresponding to a protection circuit, among the plural protection circuits, which has first detected that a protection operation is necessary, as an alarm signal during a period in which it is detected that the protection operation is necessary, and a notification signal output circuit which, when the alarm signal is output from the alarm signal output circuit, outputs one pulse thereof equivalent to the set pulse width as a protection operation notification signal.

Abstract: A power supply controller includes an input voltage sense input and an output voltage sense input coupled to sense an input voltage and an output voltage of a power supply. A current limit circuit includes a first variable resistance coupled in parallel with a second variable resistance. The first variable resistance responsive the input voltage of the power supply and the second variable resistance is responsive to the output voltage of the power supply. The current limit circuit is coupled to generate a current limit signal in response to an equivalent resistance of the first variable resistance coupled in parallel with the second variable resistance. A drive signal generator is coupled to generate a drive signal in response to the current limit signal to drive a power switch of the power supply to limit an output power of the power supply in response to the input voltage.

Abstract: This device protects at least one electronic switching branch of an electrical conversion system against an overcurrent, each branch comprising two switching half-branches serially connected at an intermediate terminal, at least one half-branch including a switching member, each switching member comprising a first controllable switch and a diode connected in antiparallel to said first switch. The protection device includes, for each switching branch, at least one second controllable switch, each second switch being connected to the intermediate terminal or to an electrode of said diode in antiparallel to the first switch, each second switch being able to switch, under action of a controller, from an on state to an off state to protect said diode from the overcurrent, means for measuring a magnitude relative to a current able to circulate in each diode, and means for controlling each second switch, based on the measured magnitude.

Abstract: In controlling switching elements of a current source inverter, a switching loss in the switching element is prevented according to a normal switching operation for a commutation operation, without requiring any particular control. In the commutation operation of the current source inverter, a timing for driving the switching elements is controlled in such a manner that an overlap period is generated, during when both a switching element at the commutation source and a switching element at the commutation target are set to be the ON state, a resonant circuit is controlled based on the control of the switching elements having this overlap period, and resonant current of the resonant circuit reduces the switching loss upon commutation operation of the switching elements.

Abstract: A wireless communication system base station (20) includes a base station transceiver (26) that has at least one operative component (32) for facilitating wireless communications. A current limiting device (36) includes at least one field effect transistor for selectively controlling current flow to a capacitive stability device (34) associated with at least one of the operative components (32). In the disclosed example, the current limiting device (36) is in series with the capacitive stability device (34) but in parallel with the operative component (32).

Abstract: A power converter includes an inverter unit that includes a plurality of semiconductor switching elements constituting upper and lower arms and converts DC power into AC power; a gate driving unit that outputs, to the inverter unit, a gate signal used to drive gates of the plurality of semiconductor switching elements; a driving control unit that supplies the gate driving unit with a switching control signal used for the gate driving unit to output the gate signal; a first abnormality detection unit that performs over voltage detection of the DC power and over current detection of the AC power and temperature detection of the upper and lower arms; and a second abnormality detection unit that detects abnormality of the plurality of semiconductor switching elements of the upper arm and lower arms, wherein the driving control unit includes a first protection circuit and a second protection circuit.

Abstract: An inverter has a current sensor that senses a low side current before a high side of the inverter is permitted to power up. If an over-current situation is detected on the low side, powering up is prevented in order to avoid damage to the rectifier.

Abstract: A switching device includes a flowing restriction element, a conductor and a snubber resistor. The flowing restriction element has an opening and closing function to open and close a flowing path of an electric current. The conductor is connected to the flowing restriction element. The snubber resistor is connected to the flowing restriction element and constitutes a snubber circuit. The snubber resistor is disposed along the conductor.

Abstract: A current detection circuit for a power semiconductor device utilizes a sense function of the power semiconductor device. The magnitude of current flowing in power semiconductor devices 1, 11 is detected by a current-voltage conversion circuit 24 connected to sense terminals S, S of the power semiconductor devices. The detected signal is delivered to a current direction detection circuit 27, which detects the direction of the current and delivers the detected current direction signal to an external CPU 3, which in turn gives gain-setting and offset-setting signals corresponding to the current direction signal. An output gain adjuster 221 adjusts the magnitude of gain and an output offset adjuster 231 adjusts the magnitude of offset to correct for differences between the characteristics of the sense regions and the main regions of the power semiconductor devices.