Hitachi, Ltd.

Nitachi Automotive Engineering Co. Ltd.

Michimasa Horiuchi

Masahiko Ibamoto

Hiroshi Narita

Hideaki Rokutan

Toshimichi Minowa

Mitsuo Kayano

Yutaka Nishimura

Hiroshi Sato

Kazuhiko Sato

Hiroshi Katayama

Junichi Ishii

Naoyuki Ozaki

Hiroatsu Tokuda

Kenji Tabuchi

Hiroshi Ohnishi

Akira Hasegawa

Takashi Tsuboi

Shigeru Kuriyama

Jinichi Toyama

Shun-ichiro Sugimoto

Kiyoshi Nemoto

Kiyosi Nemoto

A method and apparatus to estimate slopes accurately, as well as to eliminate slope estimation errors, taking error generating conditions into account. The slope on which the vehicle is running is estimated from the vehicle speed and the engine rpm value. The result is entered to the slope estimation unit through a low pass filter, then to the navigation unit. A noise eliminator is provided to the output of the slope estimation unit so that noises can be eliminated, for example, during gear-shifting or for a certain time after the gear shifting is completed by obtaining the 'gear shifting' information from the automatic transmission control. The preceding estimated slope value is held during the noise elimination period.

Method and apparatus for eliminating noise in a slope estimation

A control unit having at least one microprocessor for receiving input data signals from sensors indicative of operating parameters of the at least one system, and for generating first control signals to control operation of said at least one system in response to said input data signals. At least one input/output unit is coupled to receive the input data signals from the sensors in a parallel transmission format and to transmit output control signals to the systems in a parallel transmission format. A backup logic system provides backup control signals when transmission of the control signal is interrupted.

Apparatus for controlling an automobile engine which is serially

The invention provides a system for controlling a vehicle engine according to a plurality of stored torque patterns for various vehicle operating environments, based upon the accelerator pedal position and the vehicle speed. A vehicle environment, detection unit evaluates the vehicle environment and a target drive shaft torque pattern is selected from the plurality of target drive shaft torque patterns stored in a torque pattern storage. A target drive shaft torque calculating unit determines a target drive shaft torque from the selected target drive shaft torque pattern, the detected accelerator pedal operating amount and the detected vehicle speed. Finally, an engine output calculator determines an engine output at which a vehicle drive shaft generates the target drive shaft torque, and outputs the determined engine output to an engine output control unit.

Engine control system limiting engine output based on vehicle operating

A transmission includes a control unit which controls engagement/disengagement of an electromagnetic clutch such that it is disengaged when it is detected that a vehicle is at a stop, and such that the vehicle creeps at a predetermined speed when pressing of an accelerator pedal is detected.

Control system for electromagnetic clutch for vehicle

An electric vehicle driven by a D.C. series motor is disclosed in which electric power is supplied from a battery to the motor through a chopper, and in which forward-motion and backward-motion commands generated by the switch operation of a driver and a torque command from an accelerator pedal are supplied to a control device having a microprocessor, to control the chopper. The control device further includes storage means which has stored therein a trouble shooting program in addition to a program for making an ordinary running control for the electric vehicle, and is provided with a connector jack for connecting a trouble-shooting operation part to the control device. When a starting switch provided in the trouble-shooting operation part is operated in the state that the trouble-shooting operation part is connected to the control device, the control device reads out the trouble shooting program, carries out trouble shooting, and displays the results of trouble shooting on a display device provided in the trouble-shooting operation part.

Trouble shooting system for electric vehicle

A chopper control apparatus comprises a chopper connected between a d.c. power supply source and a load, and a computer for performing an arithmetic operation for controlling the duty factor of the chopper. The computer responds to a clock signal supplied thereto at a predetermined period and arithmetically determines a desired duty factor of the chopper for every period. A turn-on signal generated in synchronism with the clock signal and a turn-off signal generated with a delay of period of time based on the results of the arithmetic operation are sequentially supplied to the chopper. The conducting state of the chopper is detected and the result of the detection is fetched by the computer with a predetermined time delay. The computer executes a program for determining presence or absence of a commutation failure on the basis of the result of the conducting state detection in response to the clock signal serving as an interrupt request signal.

Chopper control apparatus

A braking control apparatus for an electric motor operated vehicle including contactors for controlling the direction of rotation of a DC electric motor to effect change-over between the forward and backward modes of running of the vehicle, and a chopper circuit whose duty cycle is varied in response to the accelerator position is disclosed to comprise forward/backward change-over detecting means for detecting a change-over from the forward mode of running to the backward mode of running or vice versa, and regenerative braking activating means for effecting regenerative braking whe the forward/backward change-over detecting means detects the occurrence of change-over from the forward to the backward mode of running or vice versa.

Braking control apparatus for an electric motor operated vehicle

An electric vehicle control device is disclosed which includes a main circuit for supplying power from a d.c. power supply to a driving motor through a chopper, a phase shifter for controlling the conduction ratio of the chopper in such a manner that a current flowing through the driving motor is proportional to an instruction value determined by how much an accelerator pedal is trodden, a circuit for instructing a regenerative braking operation, and a changeover switch for changing over the main circuit between a power running state and a regenerative braking state. The changeover switch is changed over in the regenerative braking state when another power running state in the direction opposite to the current running direction is instructed in a predetermined time after the stop of a power running state where the chopper had a conduction ratio greater than a preset value.

Electric vehicle control device

A thyristor chopper whose gate signal is controlled by a magnetic phase shifter is connected between a battery and a series motor of an electric vehicle and is short-circuited by a bypass contactor as soon as the duty factor of the chopper attains 100%. In the short-circuited condition of the chopper, the magnetic phase shifter remains idle and does not participate in the control operation although the instruction current and the actual motor current are kept applied to its control windings. Therefore, the level of the output from the magnetic phase shifter is indicative of the value of the actual motor current when the instruction current value is fixed, so that the actual motor current value can be detected by detecting the output level from the magnetic phase shifter. When the actual motor current value is detected to be excessively large, the bypass contactor short-circuiting the chopper is released to decrease the value of the motor current, while when the actual motor current value is detected to be excessively small, a field-weakening contactor is closed to connect a field-weakening resistor in parallel with the field winding of the series motor so as to accelerate the motor by the field-weakening control.

Chopper control system

A motor control apparatus to supply current from a D-C source to an electric motor has a thyristor chopper circuit, the duty factor of which is controlled depending on a current instruction signal. The thyristor chopper circuit is provided between the terminals of the D-C source in series with an electric motor, and has main and auxiliary thyristors. A series connection of a capacitor and a reactor, forming commutating elements, is connected across the auxiliary thyristor and oscillates to generate a pulse of current through a forward diode in order to turn off the main thyristor when the auxiliary thyristor is turned on. In addition, a saturable current transformer having first, second and third windings is provided. Through the first winding chopper current flows, and the second winding operates as the reactance of the commutating elements. The third winding is provided within the closed circuit formed when the chopper circuit is blocked, and causes current across the secondary winding to charge the capacitor of said chopper circuit.

Motor control apparatus with an improved thyristor chopper circuit

A control apparatus for an electric motor vehicle includes a control system to increase the duty cycle of a chopper circuit driving an electric drive motor of the vehicle when a spontaneous backward movement takes place upon starting of the vehicle at an uphill gradient, thereby to increase the armature and field current of the drive motor and hence the counter current braking effort or so-called plugging effort. The control apparatus assures a reliable starting of the vehicle even at an uphill gradient road.

Control apparatus for electric motor vehicles

In an electric car, wherein the powering drive and the braking drive are executed by on-off controlling a current through a d. c. motor by means of a chopper, when the electric car is below a predetermined speed, a field coil of the d. c. motor is put into a series winding connection so as to carry out full field control, and when the car is above the predetermined speed, the field coil of the d. c. motor is changed-over to a shunt winding connection so as to carry out weak field control. The duty cycle of the chopper is controlled with the running state of the electric car taken into consideration in order that the field current at the time when the series winding connection has been changed-over to the shunt winding connection may become substantially equal to a value before the change-over, whereby the transient change of the current between before and after the change-over of the field coil is suppressed.

Control apparatus for an electric car

Regenerative brake control system for DC motor, in which a resistor is inserted in the motor circuit to effect regenerative brake control from a high speed by use of a chopper. In the voltage control region where the motor voltage less the voltage drop across the inserted resistor is controlled below an equivalent source voltage, the inserted resistor is not short-circuited, thus improving the efficiency of the regenerative brake.

Regenerative brake control system for DC motor

A regenerative braking controller for use with a series-wound DC motor which drives an electric car for railways or electric automobile and which is controlled by a thyristor chopper comprises a series-connected circuit including an armature of the DC motor, a field winding thereof and a smoothing reactor, a chopper connected in parallel with said series-circuit, a diode connected between said parallel circuit and a power supply, and a gate controller for applying a gate signal to said chopper in succession only during a period of time when said chopper is to be rendered conductive.

Growing community of inventors

Katsuta, Japan

Michimasa Horiuchi