Nissan Motor Company Limited

Kantaro Yoshimoto

Yasuhiko Kitajima

Kengo Maikawa

Yuki Nakajima

Masahiro Tsukamoto

Yasuaki Hayami

Ryuuta Yamaguchi

Kouichirou Yonekura

Sho Sato

Masanori Yamagiwa

Yutaka Tajima

An electric power converter (A) transmits and receives, via a transformer (), electric power between alternating current power source () and second battery () or between first battery () and second battery. The electric power converter includes: a common bus bar (CB) for connecting the following members to primary winding () of transformer (): first electrode of alternating current power source, and first electrode of first battery; a first switch circuit () for selectively connecting the following members to primary winding () of transformer: second electrode of alternating current power source, and second electrode of first battery; a second switch circuit () for connecting second battery to secondary winding () of transformer; and a controller () for controlling the electric power of the alternating current power source, first battery and second battery by turning on and off switches of the first and second switch circuits ().

Electric power converter with transformer

An electric power converter, electric power conversion system and method that, without using a DC-DC converter, uses and allots the electric power of plural power sources while reducing the volume and losses. At least one phase of the motor is connected to plural power sources and generates and synthesizes pulses from output voltages of plural power sources so as to drive the multi-phase AC motor. A different phase of the motor is connected to one DC power source and generates pulses from the output voltage of the power source so as to generate a driving voltage for the multi-phase AC motor. This arrangement allows use/allotment of the power of plural power sources with a reduced number of semiconductor components.

Electric power converter

A power conversion system includes first and second voltage sources for driving a multiple-phase AC motor and a control unit. The control unit is configured to compute first and second output voltage command values used to drive the multiple-phase AC motor based on a first output voltage command vector corresponding to the voltage source that is charged and a second output voltage command vector corresponding to the voltage source that is discharged. The first and second output voltage command vectors are determined so that a resultant vector of the first and second output voltage command vectors is coincident with a motor voltage command vector corresponding to a motor voltage command value, and a motor current command vector corresponding to the motor current command value is positioned within an included angle formed between the second output voltage command vector and a negative vector of the first output voltage command vector.

Power conversion system and power conversion control method

An apparatus and method for supplying a polyphase (AC) alternating current motor with driving voltages. A conversion unit is coupled to phases of the polyphase AC motor and includes a plurality of switching devices and includes, in at least one phase, a first switching device between a bus of an AC power supply and an output terminal, a second switching device between a bus of a direct current (DC) power supply and the output terminal, and a third switching device between a common bus for the AC power supply and the DC power supply and the output terminal. Driving voltages for the polyphase AC motor are generated by selecting a voltage from among voltages having potential values corresponding to the AC power supply and the DC power supply, and the selected voltage is used to operate a switch of the plurality of switching devices.

Power conversion apparatus and method and automobile

A control method for a power converter capable of reducing overall volume of a system and energy loss by using a plurality of power sources and distributing loads to them without a DCDC converter. The power converter has DC power sources and poles formed by connecting various poles of the DC sources. Voltage is applied to a load by switching between poles. The method includes operating a switch between poles of the first DC power source when a voltage command is lower than the electric potential of the second DC power source; and operating a switch between the poles of the second DC source when the voltage command is higher than the electric potential of the second DC source.

Power converter and control method for a power converter using serially-connected DC power sources

An electric power converter, electric power converter controlling method and electric power converting system for converting multi-phase alternating-current inputted from a generator and outputting multi-phase alternating current for controlling a drive of a motor. An input power factor commanding section outputs a command value of an input power factor according to an operating condition of the motor, and an input power factor controlling section controls the input power factor of the generator on the basis of the command value of the input power factor from the input power factor commanding section.

Electric power converter, electric power converter controlling method and electric power converting system

An electric power conversion apparatus includes a power converter connected to at least a first DC voltage source, a second DC voltage source and an AC electric motor. A control unit controls the power converter to generate a first PWM pulse train for supplying a first output voltage pulse train from the first DC voltage source to the AC electric motor and a second PWM pulse train for supplying a second output voltage pulse train from the second DC voltage source to the load in such a manner to form a pulse continuous in time in a final output voltage at least from each pulse of the first output voltage pulse train and a subsequent pulse of the second output voltage pulse train. A current path is provided constantly from the AC electric motor to at least one of the DC voltage sources.

Electric power conversion apparatus for plural DC voltage sources and an AC electrical load

An electrical power converter comprises a first direct current line connected to a first direct current source, a second direct current line connected to a second direct current source, an alternating current line connected to an alternating current motor, a controller, and a pulse generator. The controller determines a required torque of the alternating current motor. The controller also determines a voltage command value that substantially minimizes a copper loss of the alternating current motor while providing the required torque of the alternating current motor. The pulse generator generates an output voltage according to the voltage command value at the alternating current output.

Electrical power converter and control method

A motor drive system includes a multi-output dc power source providing three or more output potentials, and a switching circuit including switching devices connected, respectively, with the output potentials of the multi-output power source. A controller determines a command apply voltage representing a desired voltage to be applied to the motor, and further determines a plurality of command share voltages corresponding to supply voltages of the multi-output dc power source, from the command apply voltage. The controller produces a pulsed voltage by driving the switching devices in accordance with the command share voltages.

Motor drive system and process

A power conversion system for converting a dc voltage to a pulsed ac voltage includes a dc voltage source providing three or more electric potentials, and a switching circuit arranged to connect one of the potentials selectively to an output terminal. A controller produces a pulsed ac output voltage at the output terminal from the potentials of the dc voltage source by controlling an on time for connecting each of the potentials to the output terminal.

Power conversion and vehicle

A motor control apparatus having a fundamental wave current control circuit that implements feedback control on a fundamental wave component of a motor current in a dq coordinate system rotating in synchronization with the rotation of the motor and a higher harmonic current control circuit that implements feedback control on a higher harmonic components of the motor current in a dhqh coordinate system rotating with a frequency which is an integral multiple of the frequency of the fundamental wave component of the motor current, eliminates the higher harmonic component of the motor current from the control deviation between a fundamental wave current command value and a motor current feedback value.

Motor control apparatus and motor control method

A 3-phase AC current flowing to a 3-phase synchronous motor is converted through coordinate conversion to a d-axis current id and a q-axis current iq in a dq-axis coordinate system which rotates in synchronization with the motor rotation and a phase &#x3b4; of a rectangular wave voltage is calculated based upon the current deviation between a q-axis current command value iq* and the q-axis current iq. A 3-phase rectangular wave voltage is generated from a DC source based upon the calculated phase &#x3b4; and is applied to the 3-phase synchronous motor.

Limits are imposed on a fundamental voltage command value calculated at a fundamental current control circuit that controls a fundamental component of a 3-phase AC motor current in a dq-axis coordinate system rotating in synchronization with the rotation of the 3-phase AC motor by using predetermined limit values and limits are imposed on a higher harmonic voltage command value calculated in an orthogonal coordinate system (a higher harmonic coordinate system) rotating at a frequency set to an integral multiple of the frequency of the fundamental component in the 3-phase AC motor current by using a predetermined limit values. The voltage command values resulting from the limit processing are added together and a voltage corresponding to the sum is applied to the AC motor for drive control.

A motor control apparatus comprises a fundamental current control device that controls a fundamental current in a 3-phase AC motor in an orthogonal coordinate system constituted of a d-axis and a q-axis rotating in synchronization with the rotation of the 3-phase AC motor, a higher harmonic current control device that controls a higher harmonic current in the motor in an orthogonal coordinate system constituted of a dh-axis and a qh-axis rotating at a frequency that is an integral multiple of the frequency of the fundamental component of the current flowing to the motor, an estimating device that estimates the level of the harmonic speed electromotive force in the motor in the dhqh-axis coordinate system and a compensating device that compensates the harmonic speed electromotive force estimated by the estimating device.

A motor control apparatus comprises a fundamental current command value determining device that determines a fundamental current command value for a motor current based upon at least a torque command value for an AC motor, a higher harmonics current command value determining device that determines a higher harmonics current command value for the motor current and a current control device that controls the current flowing to the AC motor based upon the fundamental current command value and the higher harmonics current command value.

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Yokohama, Japan

Kantaro Yoshimoto