Hitachi, Ltd.

Hitachi Automotive Engineering Co., Ltd.

Hitachi Car Engineering Co., Ltd.

Nobunori Matsudaira

Sanshiro Obara

Hiroyuki Yamada

Ryoso Masaki

Shigeyuki Yoshihara

Kazuyoshi Sasazawa

Satoru Kaneko

Shotaro Naito

Hiroshi Katada

Taizou Miyazaki

Eiichi Ohtsu

Suetaro Shibukawa

Akio Yasukawa

Hirohisa Yamamura

Toshisada Mitsui

A method and apparatus for driving an electric vehicle having a synchronous traction motor. A peak value of induced electromotive force of the synchronous motor at a maximum allowable rotating speed is set to a value which is lower than an allowable voltage of the smoothing capacitor of the inverter and lower than a maximum allowable voltage of the power switching elements composing the inverter. The synchronous motor is thus constructed so that a peak value V,of the maximum induced electromotive force at the maximum allowable rotating speed N,of the synchronous motor satisfies a relation of V,&lE;V,where V,is an allowable voltage of the smoothing capacitor.

Driving system for electric vehicle

A control apparatus for a synchronous generator system has: a voltage instruction generator for generating voltage instructions (V,*, V,*, V,*) based on an output power reference (P*) of the synchronous generator, currents (I,, I,) flowing through the synchronous generator and position information (&thgr;,, &ohgr;,) of magnetic poles of the synchronous generator; a zero crossing point detector for detecting a point that the voltage (V,) of the synchronous generator passes through zero volt.; and a magnetic pole position calculator for calculating the information (&thgr;,, &ohgr;,) on the position of magnetic poles of the synchronous generator on the basis of the voltage instruction (V,*) and the power reference (P*) when the synchronous generator is under the generation mode, and on the basis of an output signal of the zero crossing point detector when the synchronous generator is under the stand-by mode.

Control apparatus for a synchronous generator system and a hybrid-type electric vehicle using it

An apparatus for steadily and efficiently controlling a synchronous motor is equipped with a function for generating dq-axis current commands so that the terminal voltage of the synchronous motor may not exceed the voltage which a power converter can output even at a current transition time, a current control function for correcting a fluctuation of a D.C. input voltage, and a function for eliminating the D.C. input power to zero when performing field weakening control. The dq-axis current command generator is so built as to retrieve current command tables listing high-efficiency data in advance by torque commands and rotational speeds of the synchronous motor. There are a plurality of current command tables converting maximum terminal voltages of the synchronous motor. A means is provided to select an optimum one of said current command tables according to the D.C. input voltage. In this case, a value obtained by subtracting a preset value from the D.C. input voltage is used for this selection of an optimum current command table.

Control method and system for electric rotary machine

IGBT modules, bus bars and capacitors in an inverter main circuit are secured on the front face of a heat sink and at the back side of the heat sink a water cooling channel is formed to cool the IGBT modules. The bus bars and the capacitor, thereby the size of an inverter device used in an electric car is reduced and the duration thereof is prolonged.

Inverter device with cooling arrangement therefor

A control apparatus for a synchronous generator system has: a voltage instruction generator for generating voltage instructions (V.sub.u *, V.sub.v *, V.sub.w *) based on an output power reference (P*) of the synchronous generator, currents (I.sub.u, I.sub.v) flowing through the synchronous generator and position information (.theta..sub.0, .omega..sub.r) of magnetic poles of the synchronous generator; a zero crossing point detector for detecting a point that the voltage (V.sub.u) of the synchronous generator passes through zero volt.; and a magnetic pole position calculator for calculating the information (.theta..sub.0, .omega..sub.r) on the position of magnetic poles of the synchronous generator on the basis of the voltage instruction (V.sub.u *) and the power reference (P*) when the synchronous generator is under the generation mode, and on the basis of an output signal of the zero crossing point detector when the synchronous generator is under the stand-by mode.

Control apparatus for a synchronous generator system and a hybrid-type

In a driving system comprising a permanent magnet type synchronous machine, an electric power converter for the synchronous machine and a driving controller for driving the electric power converter, the driving controller comprises a current command generator for generating a d-axis current command and a q-axis current command of the synchronous machine, a d, q-axis current control uni for generating AC voltage command values Vu*, Vv* and Vw* based on the d-, q-axis currents from the synchronous machines, and a PWM control unit for generating driving signals for the electric power converter based on the AC voltage command values. A phase generator generates a phase signal from zero-cross point information of the AC voltage command values and a phase difference angle .delta. between induced voltage and terminal voltage of the synchronous machine; and a magnet temperature compensating unit generates a phase signal from zero-cross point information of the AC voltage command values and a phase difference angle .delta. of a .delta.-table storing phase difference angles .delta. between induced voltage and terminal voltage of the synchronous machine. The phase difference angle .delta. is compensated based on a magnet temperature.

Driving system for permanent magnet type synchronous machine suitable

In an electric vehicle having a synchronous motor as the driving source, a control system and a control method for the electric vehicle can prevent over current in the main circuit or over charging of the battery at the re-closing of an opened inverter relay and is always capable of operating the power-train system in a better condition. A control method for an electric vehicle having an inverter for supplying a direct current electric power from a battery to the synchronous motor, a smoothing capacitor, connected to the inverter in parallel for smoothing the direct current electric power, an inverter control circuit and an inverter relay for connecting and disconnecting the inverter and the smoothing capacitor to and from the battery. The inverter is controlled so as to prevent current from flowing into or flowing out of the inverter until the re-closing operation of the inverter relay is completed when the opened inverter relay is re-closed.

Control system for electric vehicle and control method therefor in which

The present invention provides a protection apparatus in a control system for an electric vehicle which is capable of performing back-up driving by using a back-up control method, without using output from sensors even if the sensor in the control system for ordinary driving is failed. When at least one of the current sensor, the speed sensor and the accelerator sensor is detected to be abnormal, a back-up control voltage v1 is output as an abnormal signal from a running back-up control circuit. As a result, the running back-up control circuit sets the limiter of the output of the current control circuit to zero and switches the control signal to the inverter from vector control to V/f voltage control.

Method and apparatus for operating an electric vehicle drive system

In an electric vehicle drive controller, a drive controller has a controlling means which incorporates means for calculating a magnetic flux command from a basic torque command, for calculating a torque current command, exciting current command and slip frequency, and for operating vector calculation, and drives the motor. Voltage or power density of the power source is input to a correction coefficient calculating means and then input to a magnetic flux generating means by a correction coefficient to correct a magnetic flux. A magnetic flux generating means calculates the magnetic flux command by limiting and correcting the magnetic flux command according to the basic torque command and rotating speed, and determines a control variable for the magnetic flux command in correspondence to the motor rotating speed and torque command. By controlling the voltage to be applied to the motor in correspondence to the quantity of state of power source, it is possible to operate a drive unit on the most efficient point and reduce the size of electric power converter.

Drive controller and control method for electric vehicle

An electric vehicle control system which maintains good driving performance under normal conditions, and can cut off driving current upon malfunction of a microcomputer before restarting. A setting circuit of a comparing and operating circuit has a set signal fixed to V2 if an accelerator pedal is released. If a microcomputer malfunctions to drive an inverter absent a depression of the accelerator pedal, a current flows from a battery and a battery current sensor generates an output signal n. If this value exceeds V2, a comparator is turned on, which also turns on a transistor to energize a relay and disconnects an inverter drive signal s to break the power supply from an inverter to the ac motor. Upon disconnection, an alarm lamp is lit to issue an alarm to the driver. The disconnection is held by a delay circuit until the power is reset.

Electric vehicle control system

A control equipment for controlling a current to the motor provided in an electric vehicle is disclosed. The control equipment has a motor torque control means for inputting the motor speed No and the motor current, and generating an inverter drive signal to control the torque of the motor, a notch filter for eliminating the mechanical resonance frequency; and a torque command generating means for generating the torque command. The control equipment for an electric vehicle is not influenced by the mechanical vibration of the electric vehicle, can generate the accurate motor torque command, and can execute the stable running control.

Control equipment for electric vehicle and control method thereof

A control system for an electric car includes a motor connected to a battery as a main power source for driving the electric car, a strong electricity unit having high voltage devices including an inverter for driving the motor based on power supplied thereto from the battery, a weak electricity unit having low voltage circuits including a microcomputer for data processing, and connection devices for connecting the strong and weak electricity units in such a relationship that a signal path is connected between the units as electrically isolated therefrom, wherein signal transmission between the strong and weak electricity units is carried out with use of the signals isolated between the units.

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Hitachi, Japan

Nobunori Matsudaira