Abstract: In accordance with at least one aspect of this disclosure, a system includes a generator controller configured to receive input from an AC power source, an exciter, and a generator, and output one or more signals to an exciter to control generation of generator output. The system also includes a rectifier controller configured to receive input from the generator controller, the exciter, and a rectifier, and output one or more control signals to the generator controller and the rectifier to control active rectification of the generator output.

Abstract: A power supply with lightning protection includes a surge voltage suppression apparatus, an electromagnetic interference control circuit, a surge current bypass apparatus, an active bridge rectifier circuit, a power factor correction circuit, and a DC-to-DC conversion circuit. The surge voltage suppression apparatus is used to increase a tolerance of a surge voltage for the power supply. The electromagnetic interference control circuit is coupled to the surge voltage suppression apparatus. The surge current bypass apparatus is used to increase a tolerance of a surge current for the power supply. The active bridge rectifier circuit is used to rectify an input voltage. The power factor correction circuit is used to adjust the rectified input voltage to provide an adjusted input voltage on a bulk capacitor. The DC-to-DC conversion circuit is used to convert the adjusted input voltage into a DC output voltage.

Abstract: A power electronic device comprising a grid side (L1, L2, L3) connected to a capacitor bank (2) is described, the capacitor bank (2) being connected to ground via a switch. Such power electronic device should be used in different types of grid with low costs. To this end a varistor (5) is connected in parallel to the switch.

Abstract: An electrical power distribution network includes: a plurality of electrical power control apparatuses, each of which include one or more signal conversion components receiving electrical power in the form of a first signal and generating a corresponding second signal, a controller that controls operation of the signal conversion components, electrical power generation components acting as sources of electrical power to at least some of the electrical power control apparatuses, and electrical power consumption components acting as sinks of electrical power from at least some of the electrical power control apparatuses. The electrical power control apparatuses operate autonomously but are interconnected so that the electrical power control apparatuses collectively maintain the voltages and frequencies of electrical power signals flowing through the electrical power distribution network at target values to compensate for variations in the sinks and/or sources of electrical power.

Abstract: A circuit arrangement includes a plurality of switch assemblies connected in series, each provided with a parallel circuit of three assembly components, in which a first assembly component is a semiconductor switch, a second assembly component is a freewheeling diode, and a third assembly component is a surge arrester. The assembly components are disposed one above the other or next to one another as an assembly component stack, the three assembly components of each switch assembly are disposed in the assembly component stack in a consecutive manner. Each two adjacent assembly components are electrically connected to one another by a direct connection. A power converter module and a method for operating a power converter module are also provided.

Abstract: Methods, non-transitory computer readable mediums, and power conversion systems with a controller configured to provide modulated inverter switching control signals at a first switching frequency in response to an inverter current being greater than a first threshold and less than a second threshold, the second threshold being greater than the first threshold. The controller is further configured to provide the inverter switching control signals at a second switching frequency in response to the inverter current being greater than the second threshold, and to provide the inverter switching control signals at a third switching frequency in response to the inverter current being less than the first threshold, where the second switching frequency is less than the first switching frequency and the third switching frequency is greater than the first switching frequency.

Abstract: An AC-DC converter can include: a rectifying circuit configured to convert an AC input voltage into a DC voltage, where at least one active switching device is included in one conductive rectifying loop of the rectifying circuit; a control circuit configured to control switching states of the active switching devices according to an output voltage of the AC-DC converter and the AC input voltage, in order to decrease an error between the DC voltage and the output voltage of the AC-DC converter; and a DC-DC converter configured to convert the DC voltage into the output voltage of the AC-DC converter.

Abstract: A circuit interrupter including a current sensor having a normal sensor output and an over current detection output, a solid state switch module structured to have a closed state to allow current to flow through the circuit interrupter and an open state to interrupt current flowing through the circuit interrupter, a gate driver structured to control the solid state switch module including a desaturation function output, wherein the gate driver is structured to cause the solid state switch module to interrupt current flowing through the circuit interrupter when the DESAT function output changes to the on state, and an electronic trip circuit structured to output a trip signal to the gate driver when the normal sensor output reaches a first threshold level or the overcurrent detection output changes to the on state.

Abstract: The invention relates to the protection of an electric drive system. If a voltage spike occurs on the input of a current converter of the electric drive system via the intermediate circuit, then in order to dissipate said voltage spike in the electric drive system, a change is made to and fro between a motor operating mode and a generator operating mode in order to dissipate the electrical energy from the intermediate circuit capacitor. For the motor operating mode and the generator operating mode, in each case suitable space phasor vectors can be predefined. This permits particularly simple and rapid activation in order to dissipate the electrical energy in the electric drive system.

Abstract: An AC-DC converting apparatus includes: a boost circuit including a reactor supplied with power supply voltage output from an alternating-current power supply, a first leg including a first upper-arm element and a first lower-arm element connected in series, and a second leg connected in parallel with the first leg and including a second upper-arm element and a second lower-arm element connected in series, and boosting the power supply voltage; and a first voltage detecting unit detecting the power supply voltage. When the power supply voltage is positive, the AC-DC converting apparatus causes the first lower-arm element and the second upper-arm element to perform boosting operation alternately every power supply cycle that is cycle of the power supply voltage, and when the power supply voltage is negative, the AC-DC converting apparatus causes the first upper-arm element and the second lower-arm element to perform boosting operation alternately every power supply cycle.

Abstract: According to the invention, a current measurement circuit for providing a measurement signal for a controller for controlling a switching of power switches of a power converter comprises a first current sensing circuit for sensing a first bidirectional current representative of a current through a first power switch of the power converter. The first current sensing circuit is being adapted to provide a first sensing signal indicative of the first bidirectional current. The current measurement circuit further comprises a second current sensing circuit for sensing a second bidirectional current representative of a current through a second power switch of the power converter. The second current sensing circuit is adapted to provide a second sensing signal indicative of the second bidirectional current.

Abstract: An electrical power distribution network is disclosed, the network can include: a plurality of electrical power control apparatuses, each of the electrical power control apparatuses including: one or more signal conversion components receiving electrical power in the form of a corresponding first signal having a corresponding first fundamental frequency and a corresponding first characteristic voltage, and generating a corresponding second signal having a corresponding second fundamental frequency and a corresponding second characteristic voltage; and a controller that controls operation of the signal conversion components to determine an output voltage and an output frequency of an output signal of the electrical power control apparatus; electrical power generation components acting as sources of electrical power to at least some of the electrical power control apparatuses; and electrical power consumption components acting as sinks of electrical power from at least some of the electrical power control

Abstract: An apparatus includes an interruption circuit in a power delivery path, and a fault detection circuit configured to provide a fault signal to selectively cause the interruption circuit to interrupt power delivery, wherein the fault detection circuit includes a fault detection integrated circuit and a sensing coil configured to sense a differential current between a phase conductive path and a neutral conductive path in the power delivery path. A processor is configured to selectively control a fault simulation circuit to simulate a fault in the power delivery path, detect a response of the fault detection circuit to the simulated fault, and determine if the response of the fault detection circuit is an expected response. The processor provides an override signal to the interruption circuit to prevent the interruption circuit from receiving a fault signal from the fault detection circuit during, and for a predetermined time after, the simulated fault.

Abstract: A dynamic bleeder-current circuit for use in a voltage regulator is provided. The dynamic bleeder-current circuit includes a first bleeder-current circuit and a second bleeder-current circuit. The first bleeder-current circuit includes an input stage, a current comparator, and a bleeder-current output stage. The input stage maps a bias current in an operational amplifier in the voltage regulator with a predetermined ratio to generate a mapped current. The current comparator compares a pull current and a sink current generated by the mapped current. The bleeder-current output stage determines whether to use a first current to discharge the load capacitor of the voltage regulator according to a comparison result from the current comparator. The second bleeder-current circuit is configured to provide a second bleeder current to discharge the load capacitor. The first current is greater than the second current, and the pull current is equal to the second current.

Abstract: An apparatus includes an interruption circuit in a power delivery path, and a fault detection circuit configured to provide a fault signal to selectively cause the interruption circuit to interrupt power delivery, wherein the fault detection circuit includes a fault detection integrated circuit and a sensing coil configured to sense a differential current between a phase conductive path and a neutral conductive path in the power delivery path. A processor is configured to selectively control a fault simulation circuit to simulate a fault in the power delivery path, detect a response of the fault detection circuit to the simulated fault, and determine if the response of the fault detection circuit is an expected response. The processor provides an override signal to the interruption circuit to prevent the interruption circuit from receiving a fault signal from the fault detection circuit during, and for a predetermined time after, the simulated fault.

Abstract: A converter module for power converter stations includes a first terminal for input/output of an electrical current to the converter module via a first connection line, a second terminal for output/input of the current from the converter module via a second connection line, and a by-pass switch connected between the first terminal and the second terminal. The converter module further includes a first switching module and a second switching module connected in series via a first node connected to either one of the first terminal and the second terminal and at least two capacitor units. The first switching module includes two switching devices and the second switching module is connected between the first node and a second node.

Abstract: A rectifier module for an active bridge rectifier having two switching elements, connected in series between two end terminals, and between which a center tap is formed, and a control circuit including a monitoring unit, a synchronization unit, and a control unit, the monitoring unit detecting a measuring voltage and outputting a request signal when the measuring voltage exceeds an upper threshold value. The synchronization unit outputs a synchronization signal to a synchronization terminal as long as the monitoring unit outputs the request signal, and otherwise to monitor the synchronization terminal for a synchronization signal. The control unit switches one of the two switching elements into a conductive state at least in sections during an activation period of time, when the monitoring unit outputs the request signal and/or when the synchronization signal is detected and is optionally recognized as valid by the monitoring.

Abstract: An optical phase detector circuit is provided that is suitable for use in an optical phase lock loop. The optical phase detector includes a first optical flip-flop circuit configured to produce a first digital output based on ON/OFF state of a first digital optical input and a digital electrical control signal. A second optical flip-flop circuit is configured to produce a second digital output based on ON/OFF state of a second digital optical input and the digital electrical control signal. An AND gate is operably coupled to both the first and second optical flip-flops. The AND gate produces the digital electrical control signal for supply to the first and second optical flip-flop circuits according to an AND function of the first and second digital outputs produced by the first and second optical flip-flop circuits.

Abstract: A voltage source converter for high voltage DC power transmission is disclosed. According to one aspect, the voltage source converter is connectable between a DC network and another electrical network to interconnect the DC network and the other electrical network. The voltage source converter includes a converter unit configured to convert power flowing between the DC network and the other electrical network and at least one fault unit. One or more of the fault units includes at least one fault module having a voltage source that is operable, in the event of a short circuit in a DC network connected to the voltage source converter, to produce a voltage that acts to reduce current flowing through the voltage source converter and the short circuit.

Abstract: A voltage controlling circuit with power sharing components is provided. The circuit includes a voltage regulator for controlling an output voltage for a load and a device in communication with the voltage regulator for power sharing.

Abstract: A method for functionally checking a vacuum switch of a traction inverter having a grid-side four-quadrant chopper and a load-side pulse inverter electrically connected in parallel on the DC side by a DC intermediate circuit. The AC side of the chopper is connected to a secondary winding of a traction transformer, with the primary winding of the traction transformer connectable to an AC grid voltage by a vacuum switch. When the vacuum switch is open, the chopper is actuated precisely when the AC grid voltage is temporally located relative to the chopper input voltage, such that the amplitude of a voltage difference between the AC grid voltage and the chopper input voltage corresponds to a predetermined test voltage. It is then checked whether current flows from the AC supply grid to the chopper. The functionality of the vacuum switch can thus be checked at any time without a test device.

Abstract: An overvoltage protection unit includes a power circuit module and a controller module. The power circuit module receives power from a power source on an AC input and includes a rectifier that converts voltage on the AC input into a DC Link output voltage, and an AC input current sensor that senses a current on the AC input. The controller module provides an output to terminate power from the power source based upon the DC Link output voltage and a sensed current from the AC input current sensor.

Abstract: The LED lighting tube compatible with an electronic ballast has two snubber circuits, a waveform conversion circuit, and at least one LED light string. The snubber circuits are connected to terminals of the LED lighting tube, and input terminals of each snubber circuit are connected to electrode pins of a corresponding terminal. Each snubber circuit has at least one resistor connected in series between the electrode pins of the corresponding terminal. The waveform conversion circuit has multiple rectifier diodes, and input terminals of the waveform conversion circuit are respectively connected to output terminals of the snubber circuits, with a recovery time of each rectifier diode being under 2.5 us. Two ends of the at least one LED light string are respectively connected to output terminals of the waveform conversion circuit, and each one of the at least one LED light string includes multiple LED units connected in series.

Abstract: Short circuit safe rectifier stage for a subsea power grid It is described a rectifier stage (251) for converting an input AC voltage to an output voltage, the rectifier stage comprising: a first AC input terminal (255); a second AC input terminal (257), wherein the input AC voltage is applicable between the first input terminal and the second input terminal; a first DC output terminal (267); a second DC output terminal (268); a first thyristor (261) connected between the first DC output terminal (267) and the first AC input terminal (255); a second thyristor (263) connected between the first DC output terminal (267) and the second AC input terminal (257); a gate control circuit (272) adapted and connected to control a first conductance state of the first thyristor (261) and to control a second conductance state of the second thyristor (263) such that the first thyristor and the second thyristor provide a rectified AC voltage between the first DC output terminal (267) and the second DC output terminal (268) a

Abstract: A converter valve unit including a plurality of parallel connected semiconducting elements, a free-wheeling diode and a control unit.

Abstract: A converter includes a converter bridge (101) adapted to transfer electrical energy between the AC terminal (102) and the DC terminal (103) of the converter. The converter also includes electrical paths bypassing the converter bridge for conducting overvoltage transients occurring in the AC terminal around the converter bridge to the DC terminal. Each electrical path includes a unidirectionally conductive semiconductor component (104a, 104b, 104c), such as a diode, and a voltage-limiting component (105) for which the ratio of voltage change to current change is small when the voltage of the voltage-limiting component is greater than a predetermined threshold voltage. Because of the overvoltage protection thus achieved, AC chokes can be omitted from the AC terminal or at least they can be designed smaller, reducing the load-dependent voltage drop of the DC terminal.

Abstract: The present invention relates to a basic function unit of voltage source converter, which is characterized in that the basic function unit includes a switching device function module, a by-pass function module, a switch protection function module, a secondary control and protection function module, and a energy storage unit. The secondary control and protection function module, the energy storage unit and the by-pass function module are all fixed on the motherboard, there is a slide rail at the bottom of the motherboard, the motherboard can move back and forth on the slide rail. The voltage source converter based on that unit is highly modular, insensitive to switch device parameters, lower output voltage change rate, and smaller dv/dt stress of equipment, smaller noise, without filter, convenient installation and maintenance.

Abstract: An electric power transmission system includes at each end of a high voltage direct current transmission line including three conductors, a converter station for conversion of an alternating voltage into a direct voltage for transmitting direct current between the stations in all three conductors. Each station has a voltage source converter and an extra phase leg connected between the two pole conductors of the direct voltage side of the converter. A third of the conductors is connected to a midpoint between current valves of the extra phase leg. An arrangement is adapted to control the current valves of the extra phase leg to switch for connecting the third conductor either to the first pole conductor or the second pole conductor for utilizing the third conductor for conducting current between the stations.

Abstract: A power converter circuit for generating a supply voltage for a power semiconductor switch. A series circuit formed of a diode unit having diodes connected in reverse and a protection circuit is connected in parallel with the power semiconductor switch. The diode voltage generates a feed voltage that is transformed, rectified, and provided as a supply voltage.

Abstract: A device has a converter which is connected to a direct voltage circuit through a short-circuit protection unit. The short-circuit protection unit is arranged at least partially in the direct voltage circuit and is provided in the direct voltage circuit to suppress short-circuit current flowing through the converter. The device contains one or more controllable power semiconductors, wherein a protection element is arranged in parallel to at least one of the controllable power semiconductors. The device prevents the negative effects of a short circuit occurring in the direct voltage network in a particularly reliable manner. For this purpose, the protection element is an energy store.

Abstract: A method and an arrangement are provided for controlling phase-specific thyristors of a half-controlled network bridge. The method includes identifying continuously a thyristor to be controlled on the basis of magnitudes of supplying phase voltages, controlling the thyristor by enabling a current flow to its gate current circuit through an inductive component of a constant current regulator, which is common to all the gate current circuits. The thyristor control includes determining a magnitude of the gate current at the potential of the gate conductor in the constant current regulator, alternately switching off the voltage producing the gate current from the gate current circuit when the gate current is higher than a first predetermined limit, and switching on the voltage producing the gate current in the gate current circuit when the gate current is lower than a second predetermined limit.

Abstract: A protection scheme to protect pulse width modulated drives is described. The scheme is implantable in both hardware and software and combinations thereof. The semiconductor devices of the drive are protected from transient signals such as power line spikes and loss of line. The present scheme uses an adaptive technique to determine the normal or steady state distortion (transients and harmonics) value in an unfiltered power signal. The present distortion value is compared to the normal distortion. If the present distortion exceeds the steady state value by a given amount, then the drive is placed in freewheel mode to protect the semiconductor devices in the drive.

Abstract: A device for converting an electric current has a phase module, which in turn has an alternating current connection and at least one direct current connection connected to an intermediate direct current circuit. The device further has an energy accumulator. A phase modulation path is formed between each direct current connection and each alternating current connection. Each phase modulation path has a series connection of submodules, which each have a power semiconductor. A semiconductor protective device is provided in parallel connection to power semiconductors of each submodule. A control unit actuates the semiconductor protective device, and energy accumulator(s) are equipped for supplying energy to the control unit. The device safely prevents damage from a short circuit on the direct-current side, even when the supply grid is connected, because a direct current connection of each phase module is connected to the intermediate direct current circuit via a direct-current switch.

Abstract: An exemplary embodiment includes a method for balancing thyristor bridge circuits, the method comprising, determining currents of thyristors in a first leg of thyristors of a thyristor bridge circuit, determining a first set of gate firing times for the thyristors in the first leg of thyristors responsive to determining the current of the thyristors in the first gate of thyristors, wherein the first set of gate firing times are operative to balance a current load between the thyristors in the first leg of thyristors, and gating the thyristors in the first leg of thyristors according to the first set of gate firing times.

Abstract: A light source device includes a light source having a plurality of light emitting sections, a plurality of wavelength conversion elements each having a periodic polarization inversion structure, and for converting wavelengths of light beams emitted from the plurality of light emitting sections into predetermined wavelengths, a temperature control medium for controlling temperature of the plurality of wavelength conversion elements, a holding member having a housing space for housing the temperature control medium, and for holding the plurality of wavelength conversion elements, and a temperature control section for controlling the temperature of the plurality of wavelength conversion elements with the temperature control medium, and the temperature control section controls the temperature of the wavelength conversion elements so that the wavelength of the light beam emitted from at least one of the plurality of wavelength conversion elements is different from the wavelength of the light beam emitted from ano

Abstract: A power converter that converts an AC power outputted from a generator into a DC power and supplies it to a battery (load). The power converter includes a thyristor (switch unit) connected between an output unit of the generator and the battery (load); and a gate control unit (control unit) for generating a triangle wave voltage having a constant peak voltage corresponding to each cycle of the AC power outputted from the generator, generating a differential voltage between the voltage supplied to the load via the switch unit and a predetermined target voltage, and controlling the conductive state of the switch unit based on the triangle wave voltage and the differential voltage.

Abstract: A power supply operable from a plurality of alternating current inputs had having protection from abnormal operation. The power supply includes a switchable rectifier and a voltage to voltage converter. Protection circuits switch off at least one of the rectifier and the converter if the rectified voltage exceeds a predetermined voltage value and/or a current through the converter exceeds a predetermined current value. The protection circuits include latch circuits to prevent cyclic operation.

Abstract: A method and an arrangement for controlling phase-specific thyristors of a half-controlled network bridge, the method comprising identifying a thyristor to be controlled on the basis of the magnitude of phase voltage, controlling the thyristor by switching on a voltage in its gate current circuit to achieve a gate current. The controlling of the thyristor comprises the steps of leading the gate current through an inductive component of the gate current circuit to the gate of the thyristor, determining the magnitude of the gate current, alternately switching off the voltage in the gate current circuit, when the gate current is higher than a preset limit, and switching on the voltage in the gate current circuit, when the gate current is lower than a preset limit.

Abstract: A kit comprising a plurality of power tools configured to operate on different operating voltages and a plurality of receivers configured to provide different output charging voltages for charging the power tools. Each receiver is configured to engage and charge only the one or more power tools having an operating voltage equal to or greater than the output charging voltage of that receiver.

Abstract: There is described a method for controlling a quenching device for a converter bridge with line regeneration, whereby the converter bridge controlled by a network-timed control circuit by ignition pulses is connected with its three inputs to the phases of a three-phase network and the two outputs of the bridge are connected to a direct-current motor which feeds, when operated as a generator, current back to the three-phase network via the bridge. The quenching device is controlled by a trigger unit which emits trigger pulses depending on the monitoring of electrical and temporary variables. The quenching device comprises, for each bridge half, a quenching condenser that can be charged by a charging circuit quenching voltage. The quenching condensers, in the event of quenching, can be connected to the bridge halves by means of switches that are controlled by the trigger unit.

Abstract: An exciter system for the field of a synchronous generator excitation is provided. The exciter system includes an AC power source; a three-phase thyristor bridge having six legs, the three-phase bridge being connectable with the AC power source, and being adapted to provide a variable DC voltage output; a thyristor in each of the six legs of the three-phase bridge, wherein the thyristors provide a path for a device current; and a three-phase AC line filter series, including series resistive and capacitive elements across each phase of the AC power source and a plurality of bleed resistors, wherein at least one bleed resistor is connected to each AC input connection of the filter.

Abstract: A drive control apparatus automatically stops a drive power source operation of a vehicle under a predetermined operation condition. When a predetermined time period lapses after the automatic stop operation of the drive power source under a condition that a key switch is still held operated, a power supply from a battery to the drive control apparatus is also automatically stopped. The predetermined time period is set to a time period that is supposed necessary until a driver or the like notices the stop of the drive power source and turns off the key switch. Thus, after the drive power source is forced to stop, the battery is protected from unnecessary power consumption by various devices in the vehicle.

Abstract: A half-controlled silicon control rectifying system and method thereof are provided. In this case, the first detection unit detects the zero cross phase of the triphase AC in input port thereof. The second detection unit detects the voltage of the DC bus. Then the control unit controls the silicon-controlled rectifying unit by software. Therefore, the efficiency of soft actuation is achieved.

Abstract: A control apparatus (202) for a starter/generator (110) of an aircraft electrical power system is provided. During a start mode of operation, AC power is provided by the control apparatus (202) to an exciter stator (114) of the starter/generator (110) which is combined with controlled AC power supplied by a start converter (106) to a main stator (116) of the starter/generator (110) to rotate and start an aircraft engine. Alternatively, during a generate mode of operation after engine start, the control apparatus (202) provides DC power to the starter/generator (110) to produce a regulated voltage output from the starter/generator (110).

Abstract: An AC-DC converter includes a DC reference voltage generation unit that creates a DC reference voltage waveform based in part on a feedback signal. The AC-DC converter also includes an SCR firing unit that receives a variable frequency power output from the generator and that provides firing signals. The AC-DC converter further includes SCRs arranged as a positive bank of SCRs and a negative bank of SCRs. The AC-DC converter further includes a modulator unit that receives the firing signals and the DC reference voltage waveform, and that respectively outputs SCR gate signals to the SCRs. The AC-DC converter also includes a filter unit provided between the positive and negative banks of SCRs. The AC-DC converter also includes a voltage feedback path for feeding back the DC output voltage as the feedback voltage waveform.

Abstract: The invention relates to a rectifying circuit comprising a bridge connection with RC protected thyristors, a direct voltage circuit with capacitance and a charging circuit containing a diode (3) or a corresponding component for charging the capacitance of the direct voltage circuit. According to the invention, a resistance, which comprises one or more resistors (4), of the RC protection of the thyristors is located in the charging circuit.

Abstract: A method and apparatus are provided for driving an electro-optic converter assembly with an information signal. The method includes the steps of disposing a resistor having a resistance substantially equal to a resistance of the electro-optic converter adjacent the electro-optic converter, coupling the electro-optic converter and resistor together, in series, to form a current loop, driving the electro-optical converter end of the current loop with the information signal and driving the resistor end of the current loop with an opposite polarity of the information signal.

Abstract: A method for controlling a parallel array of rectifier bridges includes outputting control signals to repetitively fire bridge elements; skipping repetitive firing of the elements for one out of plural counts; sensing temperatures of the elements; averaging some of the sensed temperatures to provide a corresponding average temperature for each of the parallel bridge elements; comparing one of the sensed temperatures to the corresponding average temperature; increasing the counts when the sensed temperature of one of the elements is less than the corresponding average temperature, or decreasing the counts when the sensed temperature of the one of the elements is greater than the corresponding average temperature; and setting the counts to a first predetermined value when the sensed temperature of the one of the elements is greater than a second predetermined value above the corresponding average temperature.

Abstract: An excitation control system includes a circuit breaker, a bridge and a controller. The bridge converts AC phases from the breaker to an excitation voltage. The controller includes an output to open the breaker, a first sub-system inputting voltages corresponding to the AC phases and outputting a sensed voltage, and a second sub-system inputting the excitation voltage and outputting a sensed excitation voltage. A first function detects a trip signal and responsively outputs firing signals to the bridge to provide a negative excitation voltage. A second function determines if a threshold is greater than the sensed voltage and if the trip signal is asserted, and responsively asserts the output to open the breaker. A third function determines if the trip signal is asserted and responsively delays for a predetermined time, unless a negative threshold is greater than the sensed excitation voltage, and after the predetermined time responsively asserts the output.

Abstract: A power supply including an inverter receiving a DC input signal from a DC input source (11). The inverter is comprised of two half bridges (S1A, S2A and S1B, S2B). Each inverter is driven by a signal source (13A, 13B), which outputs an AC signal. The output from each inverter is input to a first stage harmonic filter. The power supply includes an output circuit that includes first and second rectifiers (D1, D2) arranged about a point so that if the inverter attempts to drive the point beyond a predetermined first and second voltage, the respective rectifier conducts in order to return at least one of power and current to the DC input source. The output from the first harmonic filter (L1A, C1; L1B, C1) is output to a second harmonic filter (L2, C2) and is then output from the power supply.