1. Comparison of energy consumption and power losses of a conventionally controlled CVT with a Servo-Hydraulic Controlled CVT and with a belt and chain as the Torque Transmitting Element Siddharth Shastri, Andrew A Frank UC Davis HEV Center 04CVT55

2. Conventional CVT Control

3. Conventional CVT Engine driven hydraulic controller Mechanically and electrically complex High pressure bleed off – energy intensive Control Vs Efficiency Idle stop systems?

4. Servo Hydraulic Control

5. Electro hydraulic system Pressure on demand Power consumption Idle Stop 42-300V Hybrid Applications

6. UC Davis SHC CVT Setup

7. Testing Loaded and unloaded tests Characterize each system Energy and Efficiency mapping

8. Test Setup

9. Unloaded Tests Ratio2.31.510.70.4 Speed (RPM)1000200030004000 Pressure (psi)100200300400

10. Optimal operating region

12. Belt Design

13. Clamping Pressure

14. Power Consumption

15. Power Flow and Losses CVT AC150 Losses Electrical Mechanical 42V 12V ClampRatio Torque Converter Controls Sensors Friction Belt Power Input Power Output Data Flow Diagram

16. Power consumption of SHC Vs Stock 3000RPM and 100psi

17. Loaded Tests Torque input (Nm) (psi)1050100150200 Ratio 2.32622110220330440 1.51575150224299 11154107161214 0.794692137183 0.43483978117156

18. Efficiency

19. Chain Vs Belt - Unloaded

21. Chain Design

22. Loaded Tests

25. Conclusions Stock CVT 89.5% efficient SHC system is 50% more efficient The VDT Belt Optimum at Ratio 1.0 2000 – 3000 RPM Energy intensive below Ratio 1.0 GCI Chain Ratio 1.5 3000 RPM Linear with respect ratio change Exhibits about ½ the internal losses of the belt at 1:1 - lesser at overdrive

26. SHC CVT with GCI Chain 94.97% 3% more than SHC CVT with Belt 5.56% more than Stock CVT