Enhanced Efficient Thermal Control System (EETCS)

1. Enhanced Efficient Thermal Control System(EETCS) Group 18 Lucas Chokanis Daniel Ramirez Lloyd Harrison Philip Teten

2. Motivation • A Proposal from Researchers to Implement Their Algorithms • Design a Power Efficient Thermostat to Control a Vehicle’s Heating, Ventilation, and Air Conditioning (HVAC) Systems • Create a Control System That will Significantly Extend the Life-Cycle of a Vehicle’s Battery • Provide a Control System that is Feasible to adapt for Future Additions

3. Objectives • Ability to Detect Input: • Temperature of the Vehicles Interior • Temperature of the Evaporator • Extra Temperature Sensor for Researchers Use • Control Output: • Speed of the blower motor (High, Med, & Low) • Speed command of the PMSM motor. • Condenser Fan • Clutch Control? • Implement a User Interface • LCD Screen and LED’s for Feedback • Push Buttons for User Control

4. Challenges • Electrically Noisy Environment: • Use of Parts that Meet Automotive Requirements • 15 ft Transmission Lines: • PMSM Motor Control • Remote Temperature Sensors • Highly Intuitive Programming: • Giving Researchers Ease of Understanding

5. Specifications and Requirements • Voltage Recieved: • 12 VDC to 15 VDC • Output to Motors: • 12 VDC Three Speed with Separate Hi, Med, Low input • 12 VDC On/OFF 12VDC motor. • Linear 0-3.3V “ramp” speed command • Relays: • Coil Voltage of 12 VDC • Microcontroller • MSP430 • C2000

6. The Proposed System

7. Microcontroller

8. Microcontroller

9. Microcontroller The chosen microcontroller is the MSP430F2274-Q1for the following reasons: • Ultra-Low power • Code Composer Studio IDE • Qualified for Automotive applications • Sponsor provided the MSP430 Target board and USB programmer • Temperature sensor

10. Temperature Sensors

11. Temperature Sensors • Ambient temperature Sensor: • Housed on main thermostat circuit board. • Provides feedback to the user via LCD screen • Evaporator temperature Sensor: • Remote sensor location. • 15ft away from main board as required by the customer. Its purpose is to keep track of the rate at which the evaporator is cooling. • Prevents the evaporator from freezing over. • Feeds data back to the MCU to be that will be used to improve efficiency. • Auxiliary Temperature Sensor: • Remote sensor location (<15ft away from main board). • Feeds data back the MCU to be used to improve efficiency.

12. Temperature Sensors

13. Temperature Sensors The chosen temperature sensors were the ADT7320for the following reasons: • Very high accuracy rating on a wide temperature scale. • We can expect reliable temperature readings in a cold environment such as the evaporator. • User programmable with multiple features • Temperature resolution up to 16-bits.

14. Temperature Sensors

15. Temperature Sensors Communication • Extending The SPI Bus for Long Distance Communication: • For the remote sensors, it is possible that propagation delay could be significant enough to hinder data transmission. • Once we attempt to conduct SPI communications at distances greater than 15 feet, we will know if propagation delay will require a hardware solution. • If this turns out to be the case, dual differential transceivers will be used to refresh the clock signal protect the data transfer from noise. • If the signal is fed back to the master from the slave, data transmissions between the master and slave will occur at the same delayed clock signal.

16. Temperature Sensors Communication

17. User Interface

18. User Interface

19. User Interface • 4 Digits 1 Decimal Accuracy

20. LCD Display and Driver • Driver Uses Less Pin Outs • Good for Intuitive Programming

21. LCD Display and Driver

22. User Interface • 4 Digits 1 Decimal Accuracy

23. User Interface • View Changing: Scroll Through

24. User Interface • Temperature Set for Nominal Setting

25. User Interface • Setting the Blower Motor State

26. PMSM Communication

27. PMSM Communication

28. PMSM Communication Analog Out 0.165V to 2.135 10 Settings

29. PMSM Communication PWM Input

30. PMSM Communication Lowpass FilterEliminates High Frequency ComponentsMaintains Analog DC Value w0 = 1/RC = 1kHz

31. PMSM Communication Dual Differential Driver To Drive the 15’ of Cable Better Noise Immunity DO+1=DI1/2 DO-1 = -DI1/2

32. PMSM Communication Shielded Twisted Pair Higher Noise Immunity Noise Cancels

33. PMSM Communication Dual Differential Reciever R2OUT2 = (RIN2+) – (RIN2-)

34. PMSM Communication Analog Out 0.165V to 2.135 10 Settings

35. Power and Motor Control

36. Motor Control Solid-State Relays (SSRs) Vs. Electromechanical Relays:

37. Motor Control Motor Control: Choosing Relay Current Rating Blower motor current draw (low, medium, and high speeds) Note: Highlighted values are interpolated values due to limitations in test equipment.

38. Motor Control Motor Control: Choosing Relay Current Rating Condenser Fan Motor Current Draw Note: Highlighted values are interpolated values due to limitations in test equipment.

39. Motor Control

40. Power Current Draw

41. Power 3.3V P/S EFFICIENCY 5V P/S EFFICIENCY

42. Power

43. Power

44. Power

46. The Proposed System

47. Administrative Content

48. Progress

49. Concerns • Noise from motors induced into MCU • Possible Solutions: Filters, bypass capacitors, optocouplers • Multiple Temperature Sensors Sharing One SPI Interface.

50. Questions?