Abstract: A semiconductor power module capable of efficiently utilizing the performance of the module and facilitating management of the module in custody. The semiconductor power module having one or more semiconductor power switching elements and a drive unit is provided with a non-volatile memory for storing use history of the module and a drive unit. The use history contains information of one of the number of switching times of the semiconductor power switching element, the number of over-current detections of the semiconductor power switching element and a temperature rise of the semiconductor power module.

Abstract: A power conversion apparatus has a circuit configuration in which a collector voltage of an IGBT is divided. It also has a unit which protects the IGBT against overvoltages applied to the collector by outputting a potential of a voltage dividing point to a gate of the IGBT. A case of a resistor on the high-voltage side of the voltage dividing point is fixed to an emitter potential of the IGBT.

Abstract: A semiconductor electric power converter in accordance with the present invention comprises an arm consisting of an IGBT, a capacitor connected between a collector and a gate of said IGBT, and a gate circuit connected to the gate of said IGBT for controlling the switching operation of said IGBT, wherein a plurality of said arms connected in series are connected in parallel and each midpoint of said arms connected in of series is connected to a load. Thereby the impedance between the gate terminal of the IGBT and the gate circuit is decreased when the gate voltage is higher than the gate voltage command value or the impedance between the gate and the emitter of the IGBT is decreased when the collector voltage is high so that an electric charge stored in the gate is rapidly discharged.

Abstract: A semiconductor electric power converter in accordance with the present invention comprises an arm consisting of an IGBT, a capacitor connected between a collector and a gate of said IGBT, and a gate circuit connected to the gate of said IGBT for controlling the switching operation of said IGBT, wherein a plurality of said arms connected in series are connected in parallel and each midpoint of said arms connected in series is connected to a load. Thereby the impedance between the gate terminal of the IGBT and the gate circuit is decreased when the gate voltage is higher than the gate voltage command value or the impedance between the gate and the emitter of the IGBT is decreased when the collector voltage is high so that an electric charge stored in the gate is rapidly discharged.

Abstract: A semiconductor power converting apparatus includes a semiconductor element for controlling a current flowing between a collector and an emitter in response to a gate condition, a driving device connected to the gate, for driving the gate in response to a drive signal entered thereinto, a voltage applying device for applying both a forward bias and a reverse bias to the gate so as to set the emitter of the semiconductor element to a neutral potential, and a voltage dividing device for dividing a voltage appearing between the collector and the emitter of the semiconductor element, in which the drive signal is under OFF state, a voltage produced based upon the divided voltage by the voltage dividing device is applied to the gate, and the gate voltage is controlled in response to the voltage appearing between the collector and the emitter of the semiconductor element, thereby reducing the snubbed loss.

Abstract: A semiconductor power converting apparatus includes a semiconductor element for controlling a current flowing between a collector and an emitter in response to a gate condition, a driving device connected to the gate, for driving the gate in response to a drive signal entered thereinto, a voltage applying device for applying both a forward bias and a reverse bias to the gate so as to set the emitter of the semiconductor element to a neutral potential, and a voltage dividing device for dividing a voltage appearing between the collector and the emitter of the semiconductor element, in which the drive signal is under OFF state, a voltage produced based upon the divided voltage by the voltage dividing device is applied to the gate, and the gate voltage is controlled in response to the voltage appearing between the collector and the emitter of the semiconductor element, thereby reducing the snubbed loss.

Abstract: A semiconductor power converting apparatus includes a semiconductor element for controlling a current flowing between a collector and an emitter in response to a gate condition, a driving device connected to the gate, for driving the gate in response to a drive signal entered thereinto, a voltage applying device for applying both a forward bias and a reverse bias to the gate so as to set the emitter of the semiconductor element to a neutral potential, and a voltage dividing device for dividing a voltage appearing between the collector and the emitter of the semiconductor element, in which the drive signal is under OFF state, a voltage produced based upon the divided voltage by the voltage dividing device is applied to the gate, and the gate voltage is controlled in response to the voltage appearing between the collector and the emitter of the semiconductor element, thereby reducing the snubbed loss.

Abstract: In a semiconductor device, such as a diode and thyristor, having at least one pn junction between a pair of main surfaces, a first main electrode formed on the surface of one of the main surfaces and a second main electrode formed on the surface of the other one of the main surfaces, a semiconductor lattice defect is formed such that its lattice defect density increases gradually in the direction from the first main electrode to the second main electrode. Since the distribution of the carrier density in the conduction state can be flattened, the reverse recovery charge can be reduced substantially without causing the ON-state voltage to increase.

Abstract: In a cooling control system for controlling cooling of an engine room of an engine, a water pump and/or cooling fans are arranged within the engine room to cool same, and electric motors electrically drive the water pump and cooling fans. A control unit compares a temperature of the engine detected by a temperature sensor with a plurality of different predetermined values, and based upon results of the comparison, controls the electric motors for driving the cooling fans in such a manner that as the detected temperature is higher, the flow rate of cooling air flowing in the engine room is larger. The control unit is operable when abnormality occurs in sensors for sensing operating conditions of the engine, for operating the electric motors to drive the water pump and cooling fans. Alternatively, an analog circuit is operable when abnormality occurs in the control unit, for operating the electric motors to drive the water pump and the cooling fans.