A NOVEL DYNAMIC CAPACITOR COMPENSATOR/GREEN PLUG SCHEME FOR 3PHASE-4 WIRE UTILIZATION LOADS

1. A NOVEL DYNAMIC CAPACITOR COMPENSATOR/GREEN PLUG SCHEME FOR 3PHASE-4 WIRE UTILIZATION LOADS By A.M Sharaf (SM-IEEE), Roshan Chhetri Dept. of Electrical and Computer Engineering University of New Brunswick 8th May 2006

2. OUTLINE • Introduction • System Description • Dynamic Tri Loop Error Driven PI Controller • Digital Simulation Results • Result • Summary • Reference

3. Introduction • Effect of any phase load imbalance • Conductor sizes, the three phase, 4 wire systems • The common or neutral wire is the neutral of the three phase secondary windings and is usually solidly grounded. • Phase loads are balanced, the neutral return current is near zero.

4. Phase electric load is severely unbalanced, the neutral current can be large and equals to the residual vector of phase currents. • The mushrooming use of nonlinear arc type and solid state converter type electric loads can cause real challenges to power quality standards where power quality, security, and reliability are key operational issues. • The paper presents a dynamic voltage stabilization and energy saving device.

5. System Description

6. Various components • Three phase-four wire ac power supplies. • Capacitor bank as the storage input conditioning filters, • Blocking diode • MPFC-Green Plug compensator scheme • Loads: balanced nonlinear RL load, unbalanced nonlinear RL type and the unbalanced nonlinear type converter type load.

7. Dynamic Tri Loop Error Driven PI Controller

8. 3 Basic Regulating Loops. • The rms neutral current (In) tracking loop to ensure a minimum neutral returncurrent or imbalance current. • The minimum neutral rms current (Iref= 0.3 pu) reference tracking loop. • The low neutral current harmonic ripple loop for power quality enhancement.

9. Purpose of Multi-loop dynamic • To minimize switching transients • Maximize power/energy utilization under unbalanced load conditions. • The loop weighing factors is assigned to ensure loop time scaling and dominant loop (1) control action. • The control gains (Kp, Ki) are selected using a guided trial and error method to minimize an objective function as given in appendix.

10. Digital Simulation Results

11. Novel (MPFC-Green Plug) • Effective low cost energy utilization device • Power quality enhancement solution for reducing switching transients and load excursions • Use the low cost hybrid modulated tuned arm power filter and a switched capacitor bank compensator.

12. ResultUnbalanced Non Linear Load Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load

13. Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load

14. Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load

15. Dynamic Responses without MPFC_Green Plug for balanced Non Linear Load Dynamic Responses with MPFC_Green Plug for balanced Non Linear Load

16. Balanced NLL (Short Circuit case) Dynamic Responses with MPFC_ Green Plug for balanced Non Linear Load Dynamic Responses without MPFC_Green Plug for balanced Non Linear Load

17. Dynamic Responses with MPFC_ Green Plug for balanced Non Linear Load Dynamic Responses without MPFC_Green Plug for balanced Non Linear Load

18. Dynamic Responses without MPFC_Green Plug for balanced Non Linear Load Dynamic Responses with MPFC_ Green Plug for balanced Non Linear Load

19. Dynamic Responses with MPFC_ Green Plug for balanced Non Linear Load Dynamic Responses without MPFC_Green Plug for balanced Non Linear Load

20. Summary • Low cost (MPFC-Green Plug) voltage compensation device • Regulated by a dynamic error driven tri-loop switching controller • Reduce the effect of switching transients • Reduce load disturbances. • Efficient electric energy utilization, • Voltage stabilization • Power quality can be enhanced as well as system effective power utilization.

21. Using of modulated filter and compensator (MPFC-Green Plug), the phase voltages can be maintained at around 1pu • The source power factor is greatly improved. • The transient over-voltages and surge type currents are damped. • Power factor increased and load voltage regulated. • Device is a member of a family of energy saving and dynamic PWM-Modulated power filters.

22. References • [1] A.M Sharaf, A.R.N.M. Reaz Ul Haque, “A Low Cost Stand-alone Photovoltaic Scheme for Motorized Hybrid Loads,” 36th IEEE Southeastern Symposium on System Theory (SSST’04), Atlanta, Georgia, USA, March, 2004. • [2] Dr. A. M. Sharaf and René Rioux , “Modulated/Switched Dynamic Filter/Compensator (MSDFC) for Energy Efficiency, Savings and Power Quality Enhancement for Households”, Senior Thesis, UNB, May 2005. • [3] AP Sakis Meliopoulos, Power System Grounding and Transients An Introduction • [4] A.M. Sharaf, 1982, "Harmonic interference from distribution systems", IEEE, Trans. PAS, Vol. PAS-101, No. 8, August 1982, pp 2975-2981

23. [5] A.M. Sharaf and Pierre Keidi, “A Modulated Low Cost Power Filter for Single Phase Inrush Transient Loads”, Proceedings of the IEEE Computer Engineering CCECE’04 Conference, May 2-5, 2004, Niagara Falls, ON, Canada. • [6] A.M. Sharaf and P. Kreidi, “Power Quality Enhancement and Harmonic Compensation Scheme for Asymmetrical Nonlinear Loads”, Proceedings of the EPE-PEMC 2002 Conference, Dubrovnik and Cavtat, September 9-11, 2002 • [7] A.M. Sharaf and Pierre Kreidi, “Power Quality Enhancement Using a Unified Compensator and Switched Filter”, International Conference on Renewable Energy and Power Quality ICREPQ 2003, Vigo, Spain, April 9-11 • [8] A.M Sharaf and Roshan Chhetri, A Novel Household Efficient Power/Energy Utilization and Power Quality Compensator Devices

24. Authors Prof Dr A.M. Sharaf Electrical Engineering Department University of New Brunswick Roshan Chhetri (Bhutan) MScE Electrical Engineering Department University of New Brunswick

25. QUESTIONS? ?

26. THANKS