Abstract: A bidirectional switch circuit includes two switching elements connected to conduct a current in both directions. The two switching elements are connected in series to each other. Of the two switching elements, the switching element to which a reverse voltage is applied, a voltage of a source of one of the switching elements being higher than a voltage of a drain of the one, is configured to conduct a current from the source to the drain even when an on-drive signal is not being input to a gate terminal of the one.

Abstract: In a plug-in operation, a first winding which functions as an armature winding for supplying an R-phase current of a three-phase rotary electric machine, a third winding, and a second winding are connected respectively to terminals for supplying R-phase, S-phase, and T-phase currents of a three-phase power source. Thus, the S-phase current and the T-phase current are interchanged as compared with in a normal operation. Thereby, reverse rotation of a field element is intentionally caused. A reverse-rotation prevention mechanism is provided in the field element.

Abstract: A current detector and a voltage detector respectively detect a current value and a voltage value outputted from an engine generator. An operating block determines a weight constant on the basis of the current value and the voltage value, weights the operating time of an engine by using the weight constant, and integrates the weighted operating time to calculate an integral time. A judging block compares the integral time and a reference time, and gives a notification to an indicator when it judges that the integral time exceeds the reference time. Receiving the notification, the indicator makes an external indication. The current detector and the voltage detector can be made of electric circuitry, so that the life of the engine can be predicted at low costs and with high reliability.

Abstract: In a plug-in operation, a first winding which functions as an armature winding for supplying an R-phase current of a three-phase rotary electric machine, a third winding, and a second winding are connected respectively to terminals for supplying R-phase, S-phase, and T-phase currents of a three-phase power source. Thus, the S-phase current and the T-phase current are interchanged as compared with in a normal operation. Thereby, reverse rotation of a field element is intentionally caused. A reverse-rotation prevention mechanism is provided in the field element.

Abstract: To reduce a leakage current when a motor for driving a compressor is energized, with the compressor unoperated. Setting the carrier frequency of an inverter at a value lower than that used during normal operation to cause phase interruption electrification of the motor.

Abstract: A bidirectional switch circuit includes two switching elements connected to conduct a current in both directions. The two switching elements are connected in series to each other. Of the two switching elements, the switching element to which a reverse voltage is applied, a voltage of a source of one of the switching elements being higher than a voltage of a drain of the one, is configured to conduct a current from the source to the drain even when an on-drive signal is not being input to a gate terminal of the one.

Abstract: A trailer refrigeration system comprising: an electricity generator (22); an electricity-generator engine (21) for driving the electricity generator (22); a converter (23) for converting ac electric power generated by the electricity generator (22) into dc electric power; an inverter (24, 25, 26) including inverters (24), (25), (26) each for converting dc electric power from the converter (23) into ac electric power; a refrigerant circuit (30) having an electric compressor (31) and a fan (35, 36) including fans (35), (36), the electric compressor (31), the fan (35), and the fan (36) being driven respectively by ac electric power from inverters (24), (25), (26); and a control means (40) for individually controlling the speed of rotation of the electric compressor (31), the fan (35), and the fan (36).

Abstract: In a power converter including a V connection inverter circuit, harmonic components included in output voltage are reduced to achieve a reduction in a loss of a load, such as a motor. Operation of four switching elements (a3 to 3d) of a V connection inverter circuit (3) is controlled so that the locus of a flux vector ?p on a complex plane created by using voltage vectors Vp obtained by the operation of the switching elements (3a to 3d) approaches to a circle. Specifically, in order to create the locus of the flux vector ?p close to a circle by using at least three of the four voltage vectors Vp, output sequences and output periods of the voltage vectors Vp are determined.

Abstract: A current detector and a voltage detector respectively detect a current value and a voltage value outputted from an engine generator. An operating block determines a weight constant on the basis of the current value and the voltage value, weights the operating time of an engine by using the weight constant, and integrates the weighted operating time to calculate an integral time. A judging block compares the integral time and a reference time, and gives a notification to an indicator when it judges that the integral time exceeds the reference time. Receiving the notification, the indicator makes an external indication. The current detector and the voltage detector can be made of electric circuitry, so that the life of the engine can be predicted at low costs and with high reliability.

Abstract: A sub-engine (30), a compressor (40) driven by the sub-engine (30), and a refrigeration circuit (70) connected to the compressor (40) and operable in a vapor compression refrigeration cycle are provided, and the interior of a refrigerator (13) of a refrigerated vehicle (10) is cooled. A rotational speed control unit (91) for linearly controlling fluctuations in the rotational speed of the sub-engine (30) such that the refrigeration capacity grows or declines in response to a refrigeration load is provided. A battery (51) for storing electric power and an electric generator (50) for generating electric power by the rotational drive of the refrigerating engine (30) to store the generated electric power in the battery (51) are provided. A fan motor (7a) for the refrigeration circuit (70) is selectively connectable to the electric generator (50) and the battery (51) such that power is fed from one of the electric generator (50) and the battery (51) to the fan motor (7a).

Abstract: A trailer refrigeration system comprising: an electricity generator (22); an electricity-generator engine (21) for driving the electricity generator (22); a converter (23) for converting ac electric power generated by the electricity generator (22) into dc electric power; an inverter (24, 25, 26) including inverters (24), (25), (26) each for converting dc electric power from the converter (23) into ac electric power; a refrigerant circuit (30) having an electric compressor (31) and a fan (35, 36) including fans (35), (36), the electric compressor (31), the fan (35), and the fan (36) being driven respectively by ac electric power from inverters (24), (25), (26); and a control means (40) for individually controlling the speed of rotation of the electric compressor (31), the fan (35), and the fan (36).

Abstract: To reduce a leakage current when a motor for driving a compressor is energized, with the compressor unoperated. Setting the carrier frequency of an inverter at a value lower than that used during normal operation to cause phase interruption electrification of the motor.