Abstract: An electric motor drive device includes a smoothing capacitor and an inverter, and further includes an overvoltage protection unit for overvoltage protection for the smoothing capacitor, and a phase short-circuit control unit. The overvoltage protection unit includes: a discharge circuit having a discharge resistor and an IGBT connected in series; and a first determination circuit which determines, with determination delay, that smoothing capacitor voltage exceeds first set voltage, and turns on the IGBT. The phase short-circuit control unit is provided in a control device for drive-controlling the inverter and includes a second determination circuit which determines, with a determination period longer than the determination delay of the first determination circuit, that smoothing capacitor voltage exceeds second set voltage lower than the first set voltage, to perform phase short-circuit control for the inverter.

Abstract: An electric motor drive device includes a smoothing capacitor and an inverter, and further includes an overvoltage protection unit for overvoltage protection for the smoothing capacitor, and a phase short-circuit control unit. The overvoltage protection unit includes: a discharge circuit having a discharge resistor and an IGBT connected in series; and a first determination circuit which determines, with determination delay, that smoothing capacitor voltage exceeds first set voltage, and turns on the IGBT. The phase short-circuit control unit is provided in a control device for drive-controlling the inverter and includes a second determination circuit which determines, with a determination period longer than the determination delay of the first determination circuit, that smoothing capacitor voltage exceeds second set voltage lower than the first set voltage, to perform phase short-circuit control for the inverter.

Abstract: The main electric power source is connected to a lower-voltage side of a DC/DC converter by a first switch, and an electrical double-layer capacitor and a regulator circuit is connected to a higher-voltage side of the DC/DC converter. In addition, permanent magnets are disposed on a rotor so as to generate a magnetic field that is in a reverse direction to excitation by a field coil inside a claw-shaped magnetic pole portion of the rotor. A power supply control circuit controls opening and closing of the first switch so as to be in an open state when the engine is at rest, and so as to be set to a connected state after the regulator circuit is operated to make the alternator generate electric power to precharge the electrical double-layer capacitor after the engine is started.

Abstract: A control device controls, with regard to a regenerative current exceeding a current value set at a power migration start point, a first power storage device to be assigned with a current value set at the power migration start point and a second power storage device to be assigned with the regenerative current exceeding the current value set at the power migration start point. The control device increases a sharing ratio of the first power storage device along a curve with a lapse of time, and performs discharge from the second power storage device to the first power storage device when a charge current is equal to or smaller than the current value set at the power migration start point in a period during which the regenerative current exceeding the current value set at the power migration start point is being charged in the first power storage device.

Abstract: The main electric power source is connected to a lower-voltage side of a DC/DC converter by a first switch, and an electrical double-layer capacitor and a regulator circuit is connected to a higher-voltage side of the DC/DC converter. In addition, permanent magnets are disposed on a rotor so as to generate a magnetic field that is in a reverse direction to excitation by a field coil inside a claw-shaped magnetic pole portion of the rotor. A power supply control circuit controls opening and closing of the first switch so as to be in an open state when the engine is at rest, and so as to be set to a connected state after the regulator circuit is operated to make the alternator generate electric power to precharge the electrical double-layer capacitor after the engine is started.

Abstract: A power supply system is provided with devices of generating an electric power, controlling an amount of power generation, charging an electric power having been generated, converting an electric power having been generated, charging an electric power having been converted, operating an electric load by an electric power having been converted, and detecting a short-circuit fault of input/output of a DC converter. In the case of detecting an input/output short-circuit fault of the DC converter, from the input/output short-circuit detector to the generator controller, an instruction is given such that the generator is switched to make a power generation at a predetermined constant voltage determined based on a voltage of the circuit arrangement.

Abstract: A power supply system is provided with devices of generating an electric power, controlling an amount of power generation, charging an electric power having been generated, converting an electric power having been generated, charging an electric power having been converted, operating an electric load by an electric power having been converted, and detecting a short-circuit fault of input/output of a DC converter. In the case of detecting an input/output short-circuit fault of the DC converter, from the input/output short-circuit detector to the generator controller, an instruction is given such that the generator is switched to make a power generation at a predetermined constant voltage determined based on a voltage of the circuit arrangement.

Abstract: Disclosed is a radio wave marker reception antenna which is not easily affected by disturbance noises, such as a broadcast wave, which are set to the same frequency band as the radio wave signal conveying driving assisting information. The radio wave marker reception antenna is equipped with a cover which is formed of a conductive material and which has a prism-like, cylindrical, conical, dome-shaped, or forwardly broadening configuration. The cover may be installed such that it is inclined from the position where its lower side is oriented vertically downward to a position where its lower side is directed obliquely forward. Further, the interior of the cover may be filled with a non-conductive material.