1. MOTOR SPEED CONTROLLER Project Three Ewan, Dave, Mitch, Simon, James and Chris

2. Background Motor Control DC Series Motor. Can be used for a variety of Industrial applications.  Pumps  Electric Trains Motor control achieved through varying terminal voltage across the motor armature. DC series type motor [2]Series DC motor Circuit [1]

3. Background Siemens PLC S7-314C_2DP Industrial type PLC Middle of the range model Two S7’s were used for this project to act as a controller and process. Siemens S7-300 [3]

4. PLC’s of the Past Controller for Ferag Publishing Winder TTL and wire wrapped pins Siemens Controller circa 1980

5. Background HMI TP177B-PN/DP 6”  Discontinued model Ability to adjust outputs and read operating conditions TP177- Siemens HMI [4]

6. Objectives Utilise two Siemens PLC’s. (Controller and Process) Utilise PID control for the Process in TIA.  Set point tracking  Compensation load variations on the motor Additional Objectives:  Correctly operating visual indicators through the HMI  Delivery as a single multi-PLC project

7. Design: Overall Design Controller and Process Design

8. Design: Initial Planning Identified early that planning would be extremely important for managing 6 team members.  Differing programming styles  Strengths and weaknesses Project leader nominated. The group decided on modelling a DC series motor.  Identified metrics for a successful simulation. A Gantt chart was used so all team members knew their roles and responsibilities.  Controller PLC  Process PLC  Report and Documentation  PID block  HMI

9. Design: Process Model Process model was created in Simulink as a second order system. A second order was selected because its response most closely represents a typical motor speed curve. A second order response Initial slope of zero. Initial response of zero. Simulates the motor ‘lag’ in response to a set point change.

10. Design: Process Model Discretised using Euler approximations. This was done because it enables easy manipulation of gain, natural period and damping coefficient. The result of the Euler method was programmed in TIA by utilising math blocks. Noise was simulated through the use of multiple sine waves added to the final output. Load was simulated by the addition of a first order disturbance to the output.

11. Design: Controller Second order system response was controlled in the S7 using the standard PID block. The PID was originally used to achieve the desired response.  No steady state offset  Quick response  No overshoot The PID was used to accommodate the implementation of disturbance. The controller PLC also managed the extra functions through use of the HMI.

12. Design: Entire Process Simulink Model of Entire System

13. Design: HMI Interact with Controller PLC  Monitor speed and controller response  Manipulate set point  Indicate fault status Communication over MPI  Piggy-back off PLC Transfer over Ethernet  Orders of magnitude faster than MPI Substantial difficulty commissioning

14. Results Overall, system performed well.  Simulated process adequately.  Controller responded appropriately.  HMI allowed for enhanced control. Responded as desired under all test conditions.  Emergency stop and system reset  Adding and shedding load:  Over and under speed responses.

15. Improvements Additional testing/tuning of PID block to increase robustness. Increased safety measures and further condition monitoring. PLC Interfacing over MPI or Profibus instead of using digital and analogue I/O. Fault Screens on error.

16. Questions

17. References [1]DC series Motor Circuit. Online: http://electrical-engineering- portal.com/4-types-of-dc-motors-and-their-characteristics. Accessed:7/6/15.http://electrical-engineering- portal.com/4-types-of-dc-motors-and-their-characteristics [2] DC Series Motor. http://www.globalspec.com/reference/42926/203279/shunt-series- and-compound-motors. Accessed: 7/6/15. http://www.globalspec.com/reference/42926/203279/shunt-series- and-compound-motors [3] Siemens S7-300. http://www.nexinstrument.com/CPU-314C-2DP- 6ES7314-6CH04-0AB0_p_69.html. Accessed: 7/6/15.http://www.nexinstrument.com/CPU-314C-2DP- 6ES7314-6CH04-0AB0_p_69.html [4] TP177 HMI. http://www.comeon365.com/ProductInfo5165.html. Accessed: 7/6/15.http://www.comeon365.com/ProductInfo5165.html