Denso Corporation

Tomonori Kimura

Masahito Mizukoshi

Hisashi Takasu

Norihito Tokura

Fumio Ohara

Takanari Sasaya

Takeshi Inoue

Hideaki Ishihara

Atsushi Kobayashi

Hiroya Tsuji

Masakiyo Horie

Takahiro Yamada

Nobuyuki Matsui

Fan Wang

Ryousuke Inoshita

Seikoh Arimura

Takaharu Takeshita

A control circuit of a semiconductor switching element includes a gate driving circuit and a negative power source circuit. The gate driving circuit drives the semiconductor switching element disposed on a power supply path of an inductive load. The negative power source circuit is connected between output terminals of the semiconductor switching element. The negative power source circuit includes a series circuit of a capacitor and a diode in a forward direction connected from a negative potential side terminal to a positive potential side terminal of the output terminals. A common connection point of the capacitor and the diode in the negative power source circuit is connected to a negative power source terminal of the gate driving circuit.

Control circuit of semiconductor switching element

One of first and second switching devices turns on to flow a current along a current path between a potential reference output terminal of a drive-target switching device and a control terminal of the drive-target switching device to turn on the drive-target switching device. Thereby, a voltage changes between the control terminal of the drive-target switching device and the potential reference output terminal of the drive-target switching device to turn off the one of the first and second switching devices being turned on. Thereby, a potential of the control terminal of the drive-target switching device is clamped.

Semiconductor switching device drive circuit using a limited drive voltage

A power conversion apparatus includes main circuits, in which switching elements are connected in parallel with diodes, respectively. An auxiliary circuit, which is formed of a series-connected second switching element and a capacitor, is connected in parallel with the diode operating as a freewheeling diode. The switching element of the main circuit, which is opposite to the auxiliary circuit, is set to turn on at a reference time. The second switching element of the auxiliary circuit is set to turn on in advance of the reference time by an interval of a discharging time period of the capacitor in a dead time period.

Power conversion apparatus

Four energization switching devices and positive/negative switching devices are controlled to form a path charging a positive capacitor; a path connecting a power supply with the positive capacitor in series and energizing an inductor to charge a control terminal of a target switching device; a path charging the control terminal using electromagnetism in the inductor; a path supplying circulating current to the power supply when potential of the control terminal becomes higher than voltage of the power supply; a path charging a negative capacitor; a path connecting the power supply with the negative capacitor in series and energizing the inductor to discharge the control terminal; a path discharging the control terminal using electromagnetism in the inductor; and a path supplying circulating current to the power supply when potential of the control terminal becomes lower than potential of a negative terminal of the power supply.

Semiconductor switching device drive circuit

A drive circuit for a semiconductor switching element is disclosed. The drive circuit includes a power supply, a capacitor, a connection changeover unit for switching a connection form between the power supply and the capacitor, a resistor connected to a control terminal of the semiconductor switching element, first and second switching elements whose common connection point is connected to the resistor, a positive-side diode whose cathode is connected to the first switching element, a negative-side diode whose anode is connected to the second switching element, and a current conduction control circuit for controlling the connection changeover unit, and the first and second switching elements to form (i) a first path for charging the capacitor, (ii) a second path for charging the control terminal of the semiconductor switching element, and (iii) a third path for discharging the control terminal of the semiconductor switching element.

Drive circuit for semiconductor switching element

A control apparatus is to drive a power converter. The power converter has a power supply unit, a switching member electrically connected to the power supply unit, and a power accumulator electrically connected to the switching member. The control apparatus controls a rotary machine with a terminal electrically connected to the power accumulator. A calculator calculates, based on a command voltage to the rotary machine, a command value for an output current to the power accumulator and the rotary machine. A chopper control unit carries out chopper control of the power converter by switching on and off the switching member based on the command value for the output current to thereby convert a voltage across the power accumulator into a desired voltage relation to a voltage of the power supply unit.

Chopper control system for rotary machines

An EPC connected between a three phase motor and a battery fixes a voltage of the V phase of the three phase motor to a voltage potential of a positive electrode of the battery. A converter unit is placed for each of the U and W phases of the three phase motor. Each of the converter units has a chopper circuit part and a capacitor. Each of the converter units converts the voltage of the battery to a desired voltage. The voltage of each of V and W phases is adjusted until the voltage of being twice of the voltage of the battery based on the voltage potential at the positive electrode of the battery as a reference voltage. This makes it possible to adjust the absolute value of a line voltage between V and W phases until the voltage of the battery as an upper limit voltage.

Electric power conversion circuit, and control device for multiphase electric rotary machine

The control apparatus is for controlling a power conversion apparatus with a chopper circuit including at least one voltage-controlled type switching element provided with a drive circuit, and a coil to generate back electromotive force. The control apparatus includes a function of outputting an operation command signal to the drive circuit to control an output voltage of the power conversion apparatus, a second function of setting, on the basis a current flowing through the switching element, a switching speed of the switching element to such a value that noise exceeding a withstand voltage between a conduction control terminal and an output terminal of the switching element can be prevented from occurring when the switching element is switched, and a third function of adjusting the drive circuit to drive the switching element such that the switching element is switched at the switching speed set by the second function.

Control apparatus for controlling power conversion apparatus

A drive controller is provided, for controlling driving of a power conversion circuit. The power control circuit includes a switching element for increasing/decreasing an absolute value of current passing through a coil by repeating electrical ON/OFF operation, so that voltage of power storage means is converted to a desired value required by power supply means, the switching element being provided for each positive/negative polarity of output current outputted from a circuit other than the power storage means, to the power storage means. Meanwhile, the drive controller includes energy loading means and OFF-state setting means. The energy loading means loads energy on the coil through a switching element not corresponding to existing polarity of the output current, after the absolute value has been zeroed by the turn OFF of the switching element corresponding to the existing polarity, but preceding an ON operation of the switching element corresponding to the existing polarity. The OFF-state setting means set both of the switching elements corresponding to and not corresponding to the existing polarity to an OFF state, after the energy loading process.

Drive controller for power conversion circuit

The control apparatus for a power conversion apparatus having chopper circuits and a capacitor, each of which includes a switching circuit and a coil, the switching circuit being on/off-controlled in accordance with specific timings determined in accordance with a current flowing through the coil to create required voltage in the capacitor, includes a function of evenly dividing an interval between adjacent specific timings of one of the chopper circuits to produce divided timings to be allocated to the other chopper circuits, and a function of setting, for each of the other chopper circuits, an on-time period of the switching circuit such that, when the interval varies as a result of which the specific timing of each of the other chopper circuits deviates from a corresponding one of the divided timings, an interval between adjacent specific timings of each of the other chopper circuits is varied to reduce the deviation.

Control apparatus for power conversion apparatus and power conversion system

In a power switching circuit, a second commutation member has a second commutation path electrically connected in parallel to a first commutation path and a second diode provided in the second commutation path and electrically connected antiparallel to a semiconductor switching element. While the semiconductor switching element is off, the second commutation path allows a second current based on the inductive load to flow therethrough in a forward direction of the second diode within a commutation period. The second diode has a second reverse recovery time shorter than a first reverse recovery time of the first diode. A second inductance of the second commutation path is higher than a first inductance of the first commutation path.

Power switching circuit improved to reduce loss due to reverse recovery current

A power conversion circuit capable of varying an output voltage within a range from a negative voltage lower than a ground voltage to a positive voltage higher than a supply voltage, and a driving method and a drive unit are provided. A power conversion circuit includes a transformer with a 1:1 ratio between the primary winding and secondary winding, a voltage outputting capacitor, and four switches. The power conversion circuit can be operated as a DC-DC converter of a step-up type, a step-up-and-down type, a step-down type, an inverted-output step-up-and-down type, or an inverted-output step-up type by selecting two switches used for control from among the four switches and alternately turning the two switches on. By switching the operating modes of the power conversion circuit, the output voltage can be varied within a range from a negative voltage to a positive voltage higher than a supply voltage.

Power conversion circuit, driving method and drive unit thereof

A method for controlling a vertical type MOSFET in a bridge circuit is provided to reduce diode power loss and improve a reverse recovery characteristic. The method includes controlling a forward voltage of a built-in diode of the vertical type MOSFET to be a first forward voltage by setting a gate voltage of the vertical MOSFET to a first gate voltage, so that the vertical type MOSFET is switched into a first off mode; and controlling the forward voltage of the built-in diode of the vertical type MOSFET to be a second forward voltage by setting the gate voltage of the vertical MOSFET to a second gate voltage, so that the vertical type MOSFET is switched into a second off mode.

Method for controlling vertical type MOSFET in bridge circuit

In a control system, a storing unit has stored a relationship between a workload associated with rotation of a multiphase rotary electric machine and a voltage utilization factor of the multiphase rotary electric machine. The voltage utilization factor includes information representing how percentage the direct current voltage applied to a switching element is used by the multiphase rotary electric machine. A measuring unit measures change in the workload associated with rotation of the multiphase rotary electric machine. A pulse control unit carries out a single pulse control to change an on duration of the switching element to be substantially equivalent to a half cycle of a cyclic current while continuously changing the voltage utilization factor based on the relationship stored in the storing unit and the measured change of the workload.

Control system for multiphase rotary electric machines

A gate driving circuit has a variable current carrying path that switches a current carrying path among a driving target device, a DC power source and a reactor to operate in plural operation modes including at least a hold mode, a preparation mode, and an execution mode. The variable current carrying path includes a backflow path for causing a reactor current flowing through the reactor to flow back to the DC power source when a gate voltage of the driving target device deviates from a preset allowable voltage range. A drive control part sets the operation mode of the variable current carrying path to the hold mode and holds the ON state or the OFF state of the driving target device, and further switches the operation mode in sequence of the preparation mode and the execution mode, and realizes turn-on or turn-off of the driving target device.

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Obu, Japan

Tomonori Kimura