Electric Power Steering

1. ELECTRICAL POWER
STEERING
RIZWAN FAROOQ
ME-09(B)

2. Outline
• Introduction
• System Overview
• Applications & Benefits
• Questions

3. Introduction
Mainly Focusing on electro-mechanical power steering

4. Introduction
Requirements
• Should be very accurate & easy to handle
• Effort required to steer should be minimum
• Should provide directional stability
• Easy alteration of driving direction

5. Introduction
Functions
• To achieve angular motion of the front wheels to negotiate a turn
• To provide directional stability
• To provide perfect steering condition
• To facilitate straight ahead recovery after completing a turn
• To minimize tire wear

6. System Overview
Overview of Electric Power Steering
• No requirement for hydraulic assistance (Eliminating hydraulic oil)
• System provides assistance depending on the driving conditions
• Supports the “active return” function
• Easier for the driver to steer the vehicle in a straight line when the vehicle is
being affected constantly by side winds or driven up or down hills.

7. System Overview
• Types Of Electric Power Steering
• Column type EPS
• Pinion type EPS
• Dual pinion type EPS
• Offset Ball Screw type EPS
• Direct Drive type EPS

8. System Overview
The electro-mechanical power steering with dual pinion
System Components of EPS
• Steering wheel
• Steering column switch with steering angle sensor
• Steering column
• Steering moment sensor(Torque Sensor)
• Steering gear
• Electro-mechanical power steering motor
• Power steering control unit

9. System Overview
Actual View

10. System Overview
Schematic View

11. System Overview
Disassembled View

12. Functioning
There are five general modes of operation of OPS

13. Functioning

14. Functioning

15. Functioning

16. Functioning

18. Applications

19. Benefits
• No hydraulic components, for example power steering oil pump, hoses, oil
tank, filter
• No hydraulic fluid
• Space savings
• Reduction in noise
• Energy savings (fuel saving by 4%)
• No complex hose and wiring system
• Good straight-line stability
• Direct but soft application of the steering input
• No uncomfortable steering reactions over uneven driving surfaces