Electric power steering control with torque ripple and road disturbance damper
US6122579A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1999 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | May 28, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/0472
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An electric power steering control for a motor vehicle reduces motor torque ripple and road generated disturbances communicated to the vehicle handwheel while promoting system stability. In deriving an output command torque signal to the EPS motor, the control (1) derives an electric motor speed signal, (2) differentiates the electric motor speed signal, (3) stores a schedule of gain as an increasing function of electric motor torque, (4) modifies the differentiated estimated electric motor speed signal in response to the gain to provide a damping correction value and (5) derives the output command signal responsive to the damping correction. In a preferred embodiment, the control (1) stores power assist torque data as a function of handwheel torque and vehicle velocity, (2) provides a vehicle velocity signal, (3) provides a handwheel torque signal, (4) modifies the handwheel torque signal in response to the damping correction value, (5) derives a power assist torque value from the stored power assist torque data in response to the vehicle velocity signal and the modified handwheel torque signal and (6) derives the output command signal from the power assist torque value. The contr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.