Method and apparatus for controlling an electric assist steering sysem by linearizing system input-output torque gain
US5743351A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1996 |
| Grant date | Apr 28, 1998 |
| Priority date | — |
| Expiry date | May 29, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D5/0463
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control arrangement for an electric assist steering system having a variable reluctance motor (26) includes a motor position sensor (54) and an applied steering torque sensor (110). A controller determines a desired motor torque assist value in response to the applied steering torque. The controller modifies the desired torque assist value to linearize the gain relationship between the desired torque assist value and motor torque output. A plurality of look-up tables have a plurality of motor current values versus motor position values stored therein. The controller selects a first (T1) look-up table corresponding to a torque value less than the modified motor torque assist value and a second (T2) look-up table corresponding to a torque value greater than the modified motor torque assist value. A first motor current value (I1) and second motor current value (I2) are determined by interpolation. A final motor current value (ICMD) is determined by interpolating between the first and second determined motor current values. A motor control signal is provided in response to the determined final motor current value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.