The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 1988
Filed:
Feb. 17, 1987
Hitachi, Ltd., Tokyo, JP;
Abstract
A chopper control system for a vehicle driven by a shunt motor. The system is provided with an integrating circuit for generating a command value for the voltage which is to be supplied to an armature of the motor in accordance with the difference between the command value of current which is to be supplied to the armature and the detected value of current flowing through the armature, and with a voltage control circuit for generating a control signal the value of which is proportional to the above command voltage value and is inversely proportional to the power source voltage value. The gate of a chopper switch is on-off controlled by the above control signal, so that the power source voltage value is converted into a voltage value corresponding to the command voltage value and is then supplied to the armature of the motor. By virtue of this arrangement, the armature is supplied with voltage without influence from fluctuations in the power source voltage, and when any wheel slip occurs, the armature current is varied in the direction that causes reduction in the degree of wheel slip.