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:
Feb. 15, 1977
Filed:
Feb. 11, 1975
Clinton C Christianson, Minnetonka, MN (US);
Robert F Bourke, Wilson, WI (US);
Gould Inc., Rolling Meadows, IL (US);
Abstract
A propulsion system for an electrical vehicle including a linear proportional controller operable in a plurality of modes for operating a d.c. drive motor via power derived from a propulsion battery. Low speed operation is achieved in an armature control mode wherein the controller is interposed between the propulsion battery and the motor armature while the motor field is coupled directly across the battery. High speeds are attained in a field control mode wherein the controller is interposed between the battery and motor field while the armature is coupled directly across the propulsion battery, thereby eliminating controller losses from the high current armature circuit. Switching between modes is achieved in a manner which minimizes stress on the switching elements. The controller is also adapted to operate in a charger mode wherein unregulated d.c. power is fed to the controller which functions to regulate the charge provided to the battery. Overall efficiency is increased by use of a dual chopper as a power modulator element. The circuit further includes protection means for controlling or preventing operation under conditions wherein circuit elements might be damaged.