Electric power steering device
US5844387A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 18, 1996 |
| Grant date | Dec 1, 1998 |
| Priority date | — |
| Expiry date | Jan 18, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P7/04
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An electric power steering device for directly applying the power of an electric motor as an auxiliary steering power to a steering system to lower a steering force required of the driver, wherein a current detecting element in a motor current detecting unit is connected in series with the motor, and a drive control unit is operable to always drive, by a PWM signal, that side of switching elements of a bridge circuit to which the motor is connected. With this construction, a high-frequency pulse noise generated upon the PWM driving of the the switching element is absorbed by an inductance in the motor and hence a high-frequency pulse noise detected by the current detecting element can be controlled at an extremely small level. Thus, the electric power steering device can prevent generation of abnormal noises from the motor and oscillation or hunting of the steering system and provide stable steering characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.