Abstract: A drive for motor that can be operated up to a high load while improving efficiency of an inverter is provided. The drive for a motor includes: a voltage conversion circuit 2 that changes a value of a DC voltage and outputs the DC voltage; an inverter 3 that converts the DC voltage output from the voltage conversion circuit into an AC voltage, the conversion being performed by a switching operation of a switching element; and control means that controls the DC voltage output from the voltage conversion circuit and controls a voltage output from the inverter by the switching element so as to drive the motor 1. The control means executes DC voltage adjustment control in which the DC voltage output from the voltage conversion circuit is controlled based on a modulation factor of the DC voltage modulated by the inverter so that the modulation factor becomes closer to 1.

Abstract: An object is to provide a driving device capable of smoothly shifting from a starting state to a sensor-less vector control, in a case where the device drives a motor by the sensor-less vector control, and the device includes a voltage detecting circuit which detects an induced electromotive voltage of the motor. A control circuit starts the motor by rectangular wave control. A magnetic pole position of a rotor is detected based on an induced electromotive voltage of one remaining phase of the motor detected by the voltage detecting circuit. The control circuit controls a main inverter circuit based on the detected magnetic pole position, and accelerates the motor by the rectangular wave control. In a case where a predetermined shift revolution speed is reached, the control circuit shifts to vector control by the sensor-less in which the magnetic pole position detected during the rectangular wave control is used as an initial value.

Abstract: An object is to provide a driving device capable of smoothly shifting from a starting state to a sensor-less vector control, in a case where the device drives a motor by the sensor-less vector control, and the device includes a voltage detecting circuit which detects an induced electromotive voltage of the motor. A control circuit starts the motor by rectangular wave control. A magnetic pole position of a rotor is detected based on an induced electromotive voltage of one remaining phase of the motor detected by the voltage detecting circuit. The control circuit controls a main inverter circuit based on the detected magnetic pole position, and accelerates the motor by the rectangular wave control. In a case where a predetermined shift revolution speed is reached, the control circuit shifts to vector control by the sensor-less in which the magnetic pole position detected during the rectangular wave control is used as an initial value.

Abstract: For a purpose of realizing a refrigerant cycle apparatus capable of exactly detecting a pressure reverse phenomenon caused in a compression element of a compressor of a multistage compression type, in the refrigerant cycle apparatus in which the multistage compression type compressor constitutes a refrigerant circuit, including an electromotive element, and first and second compression elements driven by the electromotive element in an airtight container to suck an intermediate-pressure refrigerant gas compressed by the first compression element into the second compression element and to compress and discharge the refrigerant gas, the apparatus comprising: a sensor for detecting a discharge refrigerant pressure of the first compression element; and a control device into which an output of the sensor is input, the control device detects reverse of the discharge refrigerant pressures of the first and second compression elements based on the discharge refrigerant pressure of the first compression element.

Abstract: For a purpose of realizing a refrigerant cycle apparatus capable of exactly detecting a pressure reverse phenomenon caused in a compression element of a compressor of a multistage compression type, in the refrigerant cycle apparatus in which the multistage compression type compressor constitutes a refrigerant circuit, including an electromotive element, and first and second compression elements driven by the electromotive element in an airtight container to suck an intermediate-pressure refrigerant gas compressed by the first compression element into the second compression element and to compress and discharge the refrigerant gas, the apparatus comprising: a sensor for detecting a discharge refrigerant pressure of the first compression element; and a control device into which an output of the sensor is input, the control device detects reverse of the discharge refrigerant pressures of the first and second compression elements based on the discharge refrigerant pressure of the first compression element.

Abstract: There is provided an automotive air conditioning system, which is free from troubles in traveling itself caused by power consumption in air conditioning means in an automobile having storage means, power generation means for charging the storage means, and air conditioning means having an electric compressor driven by feeding from the storage means.

Abstract: A controlling device of a compressor is provided. A noise filter is arranged at an input of the inverter circuit that converts the commercial frequency to a driving frequency to control a motor driving a compressor mechanism, for suppressing a common mode noise of the commercial power source and the inverter circuit, and is connected to a ground through a metal frame used for receiving a compressor main body. The noise filter comprises coils connected between first capacitors and second capacitors that are connected in series between the AC power lines, and further comprises a clamper connected between nodes of the second capacitors and the metal frame for clamping a voltage and a third capacitor connected to the clamper in parallel. even though the new refrigerant, such as R410A, and the three-phase AC power source are used, the leakage current can be reduced by a simple structure and the increase of the noise terminal voltage can be also suppressed.

Abstract: There is provided an automotive air conditioning system, which is free from troubles in traveling itself caused by power consumption in air conditioning means in an automobile having storage means, power generation means for charging the storage means, and air conditioning means having an electric compressor driven by feeding from the storage means.

Abstract: A controlling device of a compressor is provided. A noise filter is arranged at an input of the inverter circuit that converts the commercial frequency to a driving frequency to control a motor driving a compressor mechanism, for suppressing a common mode noise of the commercial power source and the inverter circuit, and is connected to a ground through a metal frame used for receiving a compressor main body. The noise filter comprises coils connected between first capacitors and second capacitors that are connected in series between the AC power lines, and further comprises a clamper connected between nodes of the second capacitors and the metal frame for clamping a voltage and a third capacitor connected to the clamper in parallel. even though the new refrigerant, such as R410A, and the three-phase AC power source are used, the leakage current can be reduced by a simple structure and the increase of the noise terminal voltage can be also suppressed.