1. VIT University, Chennai
Performance Enhancement of Electronic Differential in Electric Vehicles Using a Novel Wavelet Controller
Anish Bahri, Aditya Gupta, Febin Daya J L
VIT University, Chennai
Presented by: Aditya Gupta
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2. OUTLINE OF THE TALK Introduction Brushless DC Drive
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OUTLINE OF THE TALK
Introduction
Brushless DC Drive
Electronic Differential
Wavelet Controller
Results and Discussions
Conclusion
References

3. INTRODUCTION
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1. Differential: prevents vehicle from slipping on curved roads.
2. Electronic differential: Advanced Differential for: *better stability
*better control on curved roads.

4. IEEE - ICVES 2014
3. Electronic differential- Control of PID controlled BLDC Drives 4. In this work- Replacement of PID with Wavelet controller. Comparison of simulation results through MATLAB/Simulink.

5. Fig. Block Diagram of BLDC Drive
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BRUSHLESS DC DRIVE
Fig. Block Diagram of BLDC Drive

6. ELECTRONIC DIFFERENTIAL
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ELECTRONIC DIFFERENTIAL

7. Inputs to Electronic Differential - Angular velocity of vehicle
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Inputs to Electronic Differential
- Angular velocity of vehicle
- Steering angle
Outputs of Electronic Differential
- Angular velocity of right wheel
- Angular velocity of left wheel

8. ELECTRONIC DIFFERENTIAL MODELLING
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ELECTRONIC DIFFERENTIAL MODELLING

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WAVELET CONTROLLER
Discrete Wavelet Transform (DWT) : -> Time scale representation of a digital signal.

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WAVELET SELECTION
* Simulations were carried out with different wavelets like Haar, Daubechies etc. * The Daubechies wavelet gave the best results. * The Minimum Description Length criterion is used for selection of wavelets.

11. WAVELET CONTROLLER Error signal: 1. Decomposed to-
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WAVELET CONTROLLER
Error signal:
1. Decomposed to-
-Detailed coefficients (high frequency) Approximation coefficients (low frequency)
2. Scaled by respective gain values
3. Added to generate control signal (u)
kd1,kd2.. – gains for tuning high and medium
frequency components
Ka - gain for tuning low frequency components

12. SCHEMATIC OF WAVELET CONTROL
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SCHEMATIC OF WAVELET CONTROL

13. RESULTS AND DISCUSSIONS
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RESULTS AND DISCUSSIONS
Case: Straight road followed by curved road Time Vector (s) : [ ] Speed Input (km/hr): [ ] Steering Angle Input (deg): [0° 30° 30°]

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Using PID Controller:
Fig. Results of Left and Right Wheel Speed using PID Controller

15. Using Wavelet Controller:
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Using Wavelet Controller:
Fig. Results of Left and Right Wheel Speed using Wavelet Controller
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RESULT COMPARISON

17. Peak overshoot reduction- 0.69% Settling Time reduction- 6.12%
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Peak overshoot reduction- 0.69%
Settling Time reduction- 6.12%

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CONCLUSION
-Results with Electronic differential and wavelet controlled BLDC Drives have improved. -Better stability -Better control during turns -Simulations showed that the wavelet controller performed better in both static and dynamic states thus ensuring high accuracy in the drive wheel speeds.

19. REFERENCES
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[1] Ricardo Pinto de Castro, Hugo Santos Oliveira, Jos Ricardo Soares, Nuno Miguel Cerqueira and R. E. Araujo, A new FPGA based control system for electrical propulsion with electronic Differential. [2] Guillermo A. Magallan, Cristian H. De Angelo, Guillermo Bisheimer and Guillermo Garcia, A Neighborhood Electric Vehicle with Electronic Differential Traction Control. [3] Y. E. Zhao, J. W. Zhang and X. Q. Guan. Modeling and Simulation of Electronic Differential System for an Electric Vehicle with Two-Motor-Wheel Drive. [4] Azeddine Draou, Electronic Differential Speed Control for Two in wheels Motors Drive Vehicle in 4th International Conference on Power Engineering, Energy and Electrical Drives Istanbul, Turkey, May [5] G. Stang and T. Nguyen, Wavelets and Wavelet Filter Banks. Wellesley, MA: Wellesley-Cambridge Press, [6] E. Y. Hamid and Z. I. Kawasaki, Wavelet based data compression of power system disturbances using the minimum description length criterion, IEEE Trans. Power Del., vol. 17, no. 2, pp , Apr

20. THANK YOU
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