Abstract: System and method for protecting a power converter. A system includes a threshold generator configured to generate a threshold signal, and a first comparator configured to receive the threshold signal and a first signal and to generate a comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive the comparison signal and generate a modulation signal in response to the comparison signal, and a switch configured to receive the modulation signal and adjust the input current for the power converter. The threshold signal is associated with a threshold magnitude as a function of time. The threshold magnitude increases with time at a first slope during a first period, and the threshold magnitude increases with time at a second slope during a second period. The first slope and the second slope are different.

Abstract: Each of three-phase arm of an inverter has first and second switching elements connected in series together at a connection point to the corresponding phase coil of the three-phase motor. Control device turns on the first switching element of the i-th (i is a natural number smaller than four) for a predetermined time period, and determines that the second switching element of the i-th arm has a short fault, when an overcurrent exceeding a predetermined threshold is detected within the predetermined time period. The predetermined time period is shorter than a time period from a time point of turning on the first switching element of the i-th arm to a time point of attaining the predetermined threshold by a current flowing through a path extending from a power supply line through the second switching element of the remaining arm other than the i-th arm to a ground line.

Abstract: A method for thermal protection of a frequency converter and a frequency converter includes means for controlling the output current of the frequency converter. The method includes the steps of determining predetermined data points which define a thermal current limit for a semiconductor component of the frequency converter at specific temperatures at plural switching frequencies, and determining predetermined data points which define a thermal current limit for the semiconductor component at specific temperatures at a zero converter output frequency. The method also includes determining the highest allowable thermal current as a function of a measured temperature, a determined switching frequency, and a determined output frequency based on the defined data points, and limiting the output current of the frequency converter to the determined highest allowable thermal current.

Abstract: Converters that employ synchronous rectification, such as DC/DC converters, are disclosed. These converters can control their synchronous rectifiers to selectively block or pass a negative current from flowing in their output lines. Also disclosed are converters which can operate as slaves based on timing signals from other daisy-chained converters. Open-loop synchronous rectifier driving circuitry is further disclosed to allow converters to operate independently of any timing information from their output stages.

Abstract: An active start judgment circuit is electrically connected to an AC/DC transforming power supply which has at least one standby power unit to transform AC to DC in regular conditions and a main power unit to transform the AC to the DC in an ON condition for operation of an electronic equipment. The start judgment circuit bridges the standby power unit and the main power unit, and generates a reference potential based on a voltage output from the standby power unit, and gets a power signal from the standby power unit to be compared with the reference potential to output a start signal to the main power unit to transform the AC to the DC. Thus the standby power unit can actively drive the main power unit to supply DC power to activate the electronic equipment.

Abstract: An electric power protection circuit connected in series to a secondary side circuit of a transformer in a switch mode power supply includes a voltage/current limiting device to get an electric power signal output from the secondary side circuit of the transformer that goes through current and voltage limitation before being output and a constant current/voltage controller to get the electric power signal which has the current and voltage limited by the voltage/current limiting device. The electric power signal further is undergone constant voltage/current control to achieve voltage overshoot protection.

Abstract: Even when one of IGBTs fails in a semiconductor power converter apparatus in which a plurality of semiconductor elements are connected in parallel, the remaining IGBT(s) is prevented from failing with a simple circuit configuration. The semiconductor power converter apparatus includes: a semiconductor power conversion circuit in which a first IGBT having a temperature sensing unit and a second IGBT having a current sensing unit are connected in parallel, for causing the first and second semiconductor elements to perform switching operations; an overheat protection circuit for performing overheat protection for the first and second IGBTs based on temperature information obtained from the temperature sensing unit of the first IGBT; and an overcurrent protection circuit for performing overcurrent protection for the first and second IGBTs based on current information obtained from the current sensing unit of the second IGBT.

Abstract: A method and system for utilization of power converters in an aircraft engine start system includes measurement of power converter operation data that is utilized with a mathematical model of the power converter thermal characteristics to calculate operation limits for subsequent start duty cycles. A warning indicator is utilized in the event the start duty cycle limits are exceeded. This invention can be extended for any More Electric Vehicle applications, which utilizes an electric engine start system.

Abstract: A switching circuit for a power converter includes an oscillation circuit, a first circuit, and a first comparator. The oscillation circuit generates a switching signal for regulating an output of the power converter. The first circuit generates a threshold signal. The first comparator is coupled to receive a signal representative of a current through a power switch. Besides, the first comparator generates a control signal in response to the signal and the threshold signal. A frequency of the switching signal is increased in response to the enabling of the control signal.

Abstract: The device for precharging a voltage converter (15) is provided with a precharging unit (3) capable of assuming a closed state, as well as with a control unit (4) for the said precharging unit (3), the said precharging unit (3) being capable of operating according to a precharging state limiting the value of the precharging current passing through it, the said control unit (4) being capable of commanding the operation of the precharging unit (3) according to the precharging state and, once the said precharging has been completed, of commanding the said precharging unit (3) to change over from the precharging state to the closed state. The assembly has a chopping voltage converter (15) and such a device disposed at the input of the said converter (15). The aircraft is equipped with such a device or with such an assembly.

Abstract: The system includes a current injection device in electrical communication with the switch mode power supply. The current injection device is positioned to alter the initial, non-zero load current when activated. A prognostic control is in communication with the current injection device, controlling activation of the current injection device. A frequency detector is positioned to receive an output signal from the switch mode power supply and is able to count cycles in a sinusoidal wave within the output signal. An output device is in communication with the frequency detector. The output device outputs a result of the counted cycles, which are indicative of damage to an a remaining useful life of the switch mode power supply.

Abstract: Among many embodiments, a power converter and a method for operating a power converter are disclosed. The power converter may include a pair of switches connected in series, an output transformer connected to a common node between the switches and a protection apparatus for protecting each switch from being hard driven, each switch being enabled by a gate signal and turning ON in alternating half cycles so as to drive transformer current in alternate directions through the transformer. The protection apparatus may include: a detector configured to detect whether an intrinsic diode in a first switch is conducting the transformer current; and a gate signal disabler configured in response to the detector blocking an ON gate pulse from reaching a second switch in the pair of switches so that the second switch is not turned ON while the intrinsic diode of the first switch is conducting.

Abstract: A flyback converter having an active snubber includes a transformer to receive input power. The transformer has a primary winding at a first side. The active snubber is coupled in parallel with two ends of the primary winding and has a first circumferential circuit coupling in parallel with the primary winding, a second circumferential circuit and a zero voltage switch unit. The second circumferential circuit is controlled by the zero voltage switch unit and incorporated with the first circumferential circuit to form double damping paths to reduce current and prevent resonance that might otherwise occur to a single circumferential circuit and the secondary side of the transformer.

Abstract: A switching power supply with protection function includes a transistor controlled to be on or off by a PWM signal from a PWM controller to convert a DC voltage into a square wave signal, a filter filtering the square wave signal into an output voltage signal, the output voltage signal being fed back to the PWM controller to be compared with a predetermined voltage, and a switch device having an input terminal for receiving the output voltage signal from the filter, an output terminal for connecting to a load, and a control terminal. If the voltage of the output voltage signal from the filter is not equal to the predetermined output voltage, the PWM controller will not output a signal to the control terminal of the switch device and the switch device will be in an off state.

Abstract: A transition mode power converter having an active snubber the operation of which is controlled using an auxiliary winding on the transformer of the power converter. In one embodiment, the power converter includes a transformer having a primary winding connected to a voltage source, a primary switch, an auxiliary switch, a capacitor, and an auxiliary winding on the transformer. The primary switch includes a first terminal connected to the primary winding of the transformer and a second terminal connected to a common node. The auxiliary switch includes a first terminal connected to the voltage source and to the primary winding. The capacitor is connected between a second terminal of the auxiliary switch and the first terminal of the primary switch. The auxiliary winding of the transformer is connected to a third terminal of the auxiliary switch and controls operation of the auxiliary switch via the third terminal.

Abstract: An electric power protection circuit connected in series to a secondary side circuit of a transformer in a switch mode power supply includes a voltage/current limiting device to get an electric power signal output from the secondary side circuit of the transformer that goes through current and voltage limitation before being output and a constant current/voltage controller to get the electric power signal which has the current and voltage limited by the voltage/current limiting device. The electric power signal further is undergone constant voltage/current control to achieve voltage overshoot protection.

Abstract: A switching power source is capable of conducting constant-current drooping control on a load, increasing an energy conversion efficiency on a secondary side, and improving heat radiation performance. The switching power source detects whether or not an overcurrent exceeding a reference value V6 is passed to a switching element Q1, switches a first constant current I3 and a second constant current I4 smaller than the first constant current I3 from one to another according to a result of the overcurrent detection, directly superposes the first constant current I3 on a feedback voltage V3 at an input part, superposes the second constant current I4 on an output part where the feedback voltage is converted to have an impedance lower than that at the input part, and controls the ON-period of a pulse signal supplied to the switching element Q1 according to a resultant feedback voltage, thereby achieving constant-current drooping control on a load 29.

Abstract: A switched mode power supply (SMPS) may be operated with uncoupled output inductors. Overvoltage produced by “low-load” conditions may be controlled through use of an adaptive regulating bleeder. The bleeder may comprise a shunt regulator and a power dissipation resistor connected in parallel with a load of the SMPS. As load on the SMPS is reduced below a predetermined level, the shunt regulator may begin to conduct. Current may pass through the power dissipation resistor. Power dissipation may occur at a rate sufficient to maintain continuous conductance through an output inductor of the SMPS. During normal load operation, the shunt regulator may not conduct and inefficient dissipation of power through the resistor may be avoided.

Abstract: An integrated electric-drive compressor system utilizes a high frequency drive for powering the multi-pole pair motor. The electric motor and compressor are housed in a common pressure casing. The electric motor has added permanent magnets for achieving higher ratings and higher speeds.

Abstract: In a DC to DC converter, first and second primary windings are magnetically coupled to a first secondary winding. Third and fourth primary windings are magnetically coupled to a second secondary winding. The first and second primary windings are magnetically coupled to the first secondary winding. The third and fourth primary windings are magnetically coupled to the second secondary winding. The first and third primary windings are coupled in series to form a first coil member. The second and fourth primary windings are coupled in series to form a second coil member. One end of the first coil member is coupled to the first positive power line. A first switching element is coupled between the first negative power line and the other end of the first coil member. A first capacitor is coupled between the first negative terminal and one end of the second coil member.

Abstract: An apparatus, system, and method are disclosed for a low cost fault-tolerant power supply. The invention includes a power supply that regulates a bus voltage under varying load conditions. The power supply includes at least one pulse-width modulated stage, where each pulse-width modulated stage includes at least two DC-to-DC converters connected and operating in parallel. Each converter includes a switch and a fuse connected in series where the fuse disconnects the switch in response to an over current condition sufficient to open the fuse. The power supply also includes a pulse-width modulator for each stage of the power supply that regulates a bus voltage controlled by the stage by sensing the controlled bus voltage and adjusting a switching duty cycle to regulate the controlled bus voltage to a target value. The pulse-width modulator for a stage provides a substantially identical switching duty cycle to each switch of the stage.

Abstract: An apparatus, system, and method are disclosed for a low cost self-healing power supply. The invention includes a power supply that regulates a direct current (“DC”) regulated bus to maintain a regulated bus voltage under varying load conditions. The power supply includes at least one pulse-width modulated stage, wherein each pulse-width modulated stage includes at least two switches connected in parallel. Each switch includes a fuse connected in series with the switch that disconnects the switch in response to an over current condition sufficient to open the fuse. The power supply also includes a pulse-width modulator for each stage of the power supply that regulates a bus voltage controlled by the stage by sensing the controlled bus voltage and adjusting a switching duty cycle to regulate the controlled bus voltage to a target value. The pulse-width modulator for a stage provides a substantially identical switching duty cycle to each switch of the stage.

Abstract: In one embodiment, a multi-channel power supply controller adjusts the value of an error signal to minimize overshoot and undershoot during load transients.

Abstract: A universal input voltage device is presented which may receive a wide range of regulated and unregulated input voltages, both DC and a wide range of variable frequency AC, and output a desired regulated current at a desired voltage independent of the fluctuation of input voltage and frequency. The circuit includes a preconditioning input circuit, a Buck converter circuit with over voltage protection, flyback and boost circuits, and a shutdown circuit configured to drive a predetermined electrical or electronic device.

Abstract: A method of protecting an electromechanical power transfer system from excessive peak electrical potentials, the power transfer system comprising a prime mover, a dynamoelectric machine coupled to the prime mover for generating multiphase alternating current (AC) power, and at least one multiphase AC electrical load coupled to the dynamoelectric machine by way of a multiphase AC power bus, the dynamoelectric machine having a control coil responsive to control current for varying power supplied to the electrical load, comprises the steps of: analysing electrical potentials on the power bus to generate analysed power bus characteristics; comparing the analysed power bus characteristics to predetermined power bus characteristics; simultaneously shunting power across the power bus and reducing control current to the control coil for the dynamoelectric machine when the analysed power bus characteristics approximate the predetermined power bus characteristics to reduce the measured electrical potentials; and simult

Abstract: The present invention provides a method and apparatus for detecting a continuous current of a switching current. A current signal is produced in response to a switching current of the magnetic device. By sampling the waveform of the current signal in response to the enabling of a switching signal, a first current signal and a second current signal are generated. A continuous current signal is produced according to the first current signal and the second current signal. The continuous current signal is corrected to the continuous current of the switching current.

Abstract: A DC to DC boost converter circuit receives a DC input voltage and converts it to a DC output voltage at a different voltage level than the DC input voltage. The DC to DC boost converter includes a switching power converter for receiving the input voltage on an input and converting the input voltage to an output as the DC output voltage in response to pulse control signals. A switching controller generates the pulse control signals during a switching cycle. Current sensing circuitry limits a current passing through the switching power converter. The current sensing circuitry generates an overload signal when the current exceeds a reference value. The current sensing circuitry sensing the current with a current sensing resistor having a size of at least approximately 500 ohms.

Abstract: A system for limiting AC inrush current to a power supply. The system comprises first, second, and third windings magnetically coupled to a core of a transformer of the power supply. The system also comprises a first low-voltage contactor and a second low-voltage contactor. The system further comprises a first low-voltage impedance element connected between the first low-voltage contactor and the first winding, a second low-voltage impedance element connected between the second low-voltage contactor and the first winding, a third low-voltage impedance element connected between the first low-voltage contactor and the second winding, and a fourth low-voltage impedance element connected between the second low-voltage contactor and the second winding.

Abstract: Self-powered supplies are presented for powering a power converter switch driver with power obtained from an associated snubber circuit, in which a supply circuit and a snubber circuit are connected in a series path across the switch terminals with the supply circuit receiving electrical power from the snubber and providing power to the switch driver.

Abstract: A converter ECU (2) obtains allowable power total value including at least one of discharge allowable power total value ?Wout of discharge allowable power Wout1, Wout2 and charge allowable power total value ?Win of charge allowable power Win1, Win2. Then, the converter ECU (2) determines which of the allowable power total value and an actual power value is greater, If the actual power value is smaller than the allowable power total value, the converter ECU (2) controls a converter (8-1) such that an input/output voltage value Vh attains a prescribed target voltage value, and at the same time controls a converter (8-2) such that a battery current value Ib2 attains a prescribed target current value.

Abstract: A switching mode power supply apparatus includes a conversion unit to convert input power into output power having a predetermined voltage by performing a switching operation; a light emitting unit to emit light if the voltage of the output power exceeds a predetermined threshold voltage; a light receiving unit to receive the light emitted from the light emitting unit and output a signal indicative of the voltage of the output power; a switching controller to control the switching operation of the conversion unit according to the voltage of the output power indicated by the signal output from the light receiving unit; and a disconnection unit to disconnect power applied to the light receiving unit if a voltage of the power applied to the light receiving unit exceeds a predetermined trigger voltage.

Abstract: A step up converter with overcurrent protection is disclosed. The step up converter can precisely limit the output current of the upstream device. Current from the input terminal of the converter is detected and compared with a predetermined maximum current to get a comparison value which is delivered to a close-loop regulator. The overcurrent protection is achieved by the regulator outputting a control signal to fulfill the conduction or resistance increase of a resistive element of the protection circuit. Furthermore, detection of the temperature or the output voltage may trigger shut off of the protection circuit to implement a protection function.

Abstract: A method of providing power to a load is provided. A first series resonant converter is provided. A second SRC is operably coupled to the first SRC in a cascade connected arrangement. First and second zero voltage switching (ZVS)-assistance networks are operably coupled between the first SRC and the second SRC, such that the first and second ZVS-assistance networks are providing first and second ZVS-assistant currents flowing from each ZVS-assistance network to the cascade connected arrangement of SRCs. Power from a power source is received at the cascade connected arrangement of first and second SRCs, power from a power source. The cascade connected arrangement of first and second SRCs supplies an output voltage to the load in response to receiving power from the power source.

Abstract: In one embodiment, a start-up controller for a PWM power supply controller is formed to generate a current that is substantially constant for changes in temperature and for changes in an output voltage received by the start-up controller.

Abstract: A method for thermal protection of a frequency converter and a frequency converter that comprises means for controlling the output current of the frequency converter.

Abstract: An apparatus and method are provided for suppressing the input current inrush for a voltage converter in a pre-charge stage. The voltage converter comprises a power input for receiving an input current, a power output for supplying an output voltage for a load, and an output capacitor connected to the power output. In a pre-charge stage, a current limiting device is connected between the power input and the output capacitor to limit the input current to flow therethrough, and a variable current limiting control circuit provides a control signal to the current limiting device to determine a variable maximum value for the input current.

Abstract: A power supply protection method for a power supply device includes: detecting whether an output voltage of the power supply device reaches a voltage protection threshold to generate a detection result; generating a first control signal according to a power good input signal and the detection result; utilizing a fault protection circuit to decide whether to output a fault protection signal according to the first control signal; and using a short circuit protection circuit to receive the power good input signal and determining whether to generate a second control signal according to the power good input signal. When the power good input signal is not enabled during a specific time after the power supply device is started, the short circuit protection circuit is directly used to generate the second control signal into the fault protection circuit for triggering the fault protection circuit to output the fault protection signal.

Abstract: A protective device for a vehicle electronic apparatus, which includes an inverter for converting a direct-current voltage into an alternating-current voltage for the vehicle electronic apparatus, detects a temperature of the inverter. Also, the protective device controls a power supply of the direct-current voltage to the inverter. The protective device stops the power supply to the inverter when the temperature of the inverter reaches a predetermined temperature.

Abstract: A switching power supply with protection function includes a transistor controlled to be on or off by a PWM signal from a PWM controller to convert a DC voltage into a square wave signal, a filter filtering the square wave signal into an output voltage signal, the output voltage signal being fed back to the PWM controller to be compared with a predetermined voltage, and a switch device having an input terminal for receiving the output voltage signal from the filter, an output terminal for connecting to a load, and a control terminal. If the voltage of the output voltage signal from the filter is not equal to the predetermined output voltage, the PWM controller will not output a signal to the control terminal of the switch device and the switch device will be in an off state.

Abstract: An apparatus and method for reducing the die area of a PWM controller include a protection circuit triggered by a fault index signal for counting, and the counting time is provided for a delay time required by fault verification. Therefore, fault detection circuits can be eliminated and the purpose of reducing the die area can be achieved.

Abstract: A protective circuit for a multi-level converter including a DC link capacitor bank includes: an energy absorbing element; switches, wherein at least two of the switches each couple the energy absorbing element to the capacitor bank; and a controller configured to provide control signals to the switches to selectively actuate the switches to enable control of energy dissipation and to enable control of voltage balance on the capacitor bank of the multi-level converter.

Abstract: Disclosed herein are an AC/DC converter which is simple in circuit configuration, generates little ElectroMagnetic Interference (EMI) and has no transformer so that it can be reduced in weight and size and improved in AC/DC conversion efficiency, and an AC/DC conversion method using the same. The AC/DC converter includes a rectification circuit for converting a commercial AC (85-264V) voltage into a ripple AC voltage, a first control circuit for comparing the converted ripple AC voltage with a reference voltage and outputting a first pulse control signal as a result of the comparison, a first switching circuit for switching and outputting the ripple AC voltage from the rectification circuit in response to the first pulse control signal outputted from the first control circuit, and a first charge storage circuit for smoothing the ripple AC voltage outputted from the first switching circuit to convert it into a primary DC voltage.

Abstract: In one embodiment, a current sensing circuit for a converter includes a sensing switch and a comparator. The sensing switch is coupled to a power switch within the converter for receiving a first voltage signal indicative of the current through the power switch. The sensing switch also produces a second voltage signal based on the first voltage signal. The comparator is coupled to the sensing switch for detecting an operation condition of the converter based on the second voltage signal. An offset voltage between the second voltage signal and the first voltage signal can compensate for a delay at the comparator.

Abstract: A high voltage power supply includes a current overflow prevention unit to detect a change in a load of a device that is operated by an output power supplied from a transformer and to ground filtered signals that are input to first and second comparison units according to the detection result.

Abstract: A semiconductor device has a semiconductor element connected to an input/output terminal and a reference voltage terminal, a first rectifier element connected between the input/output terminal and the reference voltage terminal, which performs rectifier operation to prevent a voltage of the input/output terminal from becoming higher than a voltage of the reference voltage terminal by a predetermined value or more, and a second rectifier element connected between the input/output terminal and the reference voltage terminal, which performs rectifier operation to prevent the voltage of the reference voltage terminal from becoming higher than the voltage of the input/output terminal by a predetermined value or more.

Abstract: A converter and a driving method thereof are provided. The converter can determine the output short state of the converter after the soft start is finished by using a detection signal that corresponds to an input signal while a switched is turned on and that corresponds to an output signal while the switch is turned off, so as to convert the input signal into the output signal according to a switching operation of the switch. The converter can determine the overload state of the converter by using a feedback voltage corresponding to the output signal, and terminate the switching operation when the converter is in an output short state or overload state.

Abstract: A device corrects the power factor in forced switching power supplies and includes a converter and a control device to obtain a regulated voltage on an output terminal. The control device comprises an error amplifier having an inverting terminal (Vout) and a non-inverting terminal receiving a reference voltage. The device includes first and second resistances coupled in series with a conduction element positioned between the first resistance and the inverting terminal of the error amplifier and a fault detector suitable for detecting the electrical connection of the conduction element with the output terminal and suitable for detecting an output signal of the second resistance. The fault detector is suitable for supplying a malfunction signal upon detecting an electric disconnection of the conduction element from the output terminal or when the output signal of the second resistance tends to zero.

Abstract: A power supply (200) is provided having a plurality of independent current limiting circuits. A first current limiting circuit (6) provides protection against a short circuit or other extraneous load conditions, while a second current limiting circuit, using a trace on a PCB as a sensing element, is programmable on the basis of a time constant and a current level.

Abstract: The present invention relates to an inrush current limiter device (4) for limiting inrushing current to a connectable load (3) comprising: at least one switchable IGBT-based limiter unit (5) for selectively limiting the inrushing current, having at least one current limiting conductor element for a limited leading of current and at least an IGBT-based switch (Q2), whereby the IGBT-based switch (Q2) is used as well as a controlled current limiter and as a by-pass element, and at least one control device (7) for controlling the IGBT-based switch (Q2), whereby the control device (7) comprises at least one IGBT-based switch supply (6) and means for realizing (8) a smooth flank of an output signal at the selected conductor element.

Abstract: A switching power supply system has a control circuit that controls an output voltage by causing a switching device to turn ON and OFF. The control circuit includes a control pulse supplying unit that supplies a pulsed signal that_keeps the switching device turned-ON and -OFF. A protection circuit shuts down the switching power supply system upon occurrence of an abnormality. A delay circuit produces a delay signal that delays by a specified time duration the termination of a state of the pulsed signal in which the pulsed signal keeps the switching device turned-ON. The protection circuit is responsive to the pulsed signal or the delay signal to switch between an operation state and a stand-by state.