UNIVERSITY OF NEW BRUNSWICK

1. UNIVERSITY OF NEW BRUNSWICK ELECTRIC POWER QUALITY, HARMONIC REDUCTION AND ENERGY SAVING USING MODULATED POWER FILTERS AND CAPACITOR COMPENSATORS MSc. Candidate: Pierre Kreidi, P.Eng. Supervisor: Dr. A. M. Sharaf

2. What is Power quality ? • Definition : “Power quality problem is any power problem manifested in voltage, current, or frequency deviation that results in failure or misoperation of customer equipment”. • Power quality can be simply defined as shown in the interaction diagram: • Harmonics • Waveform Dirtortion • Voltage Sags • Voltage Swells • Blackouts/Brownouts • Transients, Glitches • Arc Type • Temporal • Converter Type • Saturation Type • NLL-Analog/Digital Switching • Inrush • Overcurrent • Flickering

3. Why are we concerned about PQ • Electrical Business Magazine in December 2001 “as every year, North American industries lose Tens-of-Billions of Dollars in downtime due to electric faults in the quality of electric power delivered to factories and other industrial facilities” ($ 10 x 109 Lost in downtimes) • The Electric Power Research Institute (EPRI) gives a rough estimation that in 1992, 15 to 20% of the total electric utility load was nonlinear and the trend of this load nonlinearities in rising and is expected to reach 50 to 70% in the year 2000.

4. Why are we concerned about PQ • Power Quality (PQ) has caused a great concern to electric utilities with the growing use of sensitive and susceptive electronic and computing equipment (e.g. personal computers, computer-aided design workstations, uninterruptible power supplies, fax machines, printers, etc) and other nonlinear loads (e.g. fluorescent lighting, adjustable speed drives, heating and lighting control, industrial rectifiers, arc welders, etc). • All nonlinear and time varying temporal type electric loads fall generally in two wide categories, namely the analog arc (inrush/saturation) type and digital converter (power electronic) switching type. • Key Problems: Damage to sensitive equipment / Interference /Malfunction /Extra losses / Personnel Safety issues/ Poor Utilization / Poor Power Factor.

5. Why are we concerned about PQ The reasons behind the growing concern about PQ are: • The characteristics of the electric loads have changed dramatically with the proliferation of new microelectronics and sensitive computer type equipment.(Lighting controls, SMPS, Converter Loads, etc.) • Harmonics cause equipment to fail prematurely, also decrease the efficiency of the electric distribution/utilization network • Electric power systems are now highly interconnected, integrated, any system disturbance can have an extended serious economic impact particularly for large industrial type consumers due to process shutdown. • In order to stay competitive in the new deregulation electricity market, power utility companies are faced with a new challenge in providing better service in terms of supply reliability and reduced cost to their consumers.

6. Why are we concerned about PQ • Consumers are now much more aware of the power Quality problems issues, their effect on equipment failure and safety hazards. • The economical issue is of great importance to utility and customers. • In order to stay competitive in the new deregulation electricity market, power utility companies are faced with a new challenge in providing better service in terms of supply reliability and reduced cost to their consumers. • Electricity Market De-Regulation Means: • Service Security • Service Quality • Competition • Efficient Utilization • Demand Side Management

7. Power Quality Issue and Problem Formulation Power Quality issues can be roughly broken into a number of sub-categories: • Harmonics (integral, sub, super and interharmonics); Transient type, Quasi-transient and Quasi-steady state type. • Voltage swells, sags, fluctuations, flicker, glitches and transients • Voltage magnitude and frequency deviation, voltage imbalance (3ph sys.) • Hot grounding loops and ground potential rise (GPR)–Safety & Fire Hazards • Monitoring and measurement of quasi-dynamic, quasi-static and transient type phenomena is a challenging task.

8. Power Quality PQ Issue and Problem Formulation • Nonlinear loads contribute to a continued degradation in the electric supply power quality and security through the generation of quasi-steady state harmonics, and makes the harmonic issue (waveform distortion) a top priority to for all equipment manufacturer, users and Electric Utilities (New IEC, ANSI, IEEE Standards). • Severe quasi-steady state Power System harmonics are usually the important steady state problem not the transient or intermittent type, • The effect of harmonics is detrimental to the supply power quality • Lower order harmonics cause the greatest concern in the electrical distribution/utilization system Where h: Harmonic order =2,3,5….

9. Power Quality Issue and Problem Formulation • Several Standardized/defined measures commonly used for indicating the harmonic severity and content of a waveform distortion with a single number: Where V1 or I1 : Fundamental voltage and current and Vn or In: Harmonic order • Other Measures: Peak/RMS Ratio, Form Factor, (TIF)-Noise C-Message Weighting

10. Problems Caused by Harmonics • Transformer feeder over-heating • Circuit breaker inadvertent trips • Fuse blowing, especially on Distribution feeder laterals • Equipment malfunction (sensitive equipment) (e.g. ATM Machines $) • Increased KVA demand and need to oversize • Total power factor reduction PF • Waste electric energy (lossy systems, distribution losses 4-12% were reported) • Overloading of cables/conductors increased capacity systems (due to skin effect) • Triplen harmonics cause hot neutrals, GPR (safety issue/fire hazards) • Light flickering (cause premature lighting equipment damage)

11. Harmonics Standards and Guidelines • Electric Utilities, Electrical Design Engineers and major equipment Manufacturers, Production or Process Facilities throughout the world are readily adopting various Harmonic Distortion guidelines limits and strict Standards. • In the USA and Canada, IEEE-519-1992 (THD), In, current injection limits • In Europe, EN61000-3-2 • In Australia, AS 2279 is the used standard. • In the UK, the British Standard G5/3 • In Germany VDE Standards

12. Total Harmonic Distortion (THD) and Power Factor (PF) • The power factor PF for any non-sinusoidal quantities is defined by

13. SYSTEM MODELS Single Line Diagram of Radial Utilization System

14. Nonlinear Load Models Volt-Ampere (VL – IL) Arc Type Cyclical Load Temporal time-dependent (Cyclical load)

15. Nonlinear Load Models Volt-Ampere (VL – IL) Industrial Motorized Load Cyclical Motorized Modulated Fanning Effect Converter-Rectifier Modulated

16. Nonlinear Load Models Volt-Ampere (VL – IL) Limiter Type Switch Mode Power Supply (SMPS) FL-Starter Ballast Nonlinear Magnetic Saturation type

17. Nonlinear Load Models Volt-Ampere (VL – IL) Adjustable Speed Drive (ASD) Dual Loop Nonlinear

18. Switched Modulated Power Filters and Capacitor Compensators Tuned-Arm Filter (TAF) TAF + Static Capacitor Compensator C-Type Filter Asymmetrical Tuned-Arm Filter (ATAF) MPF/SPF(Family of Filters – Compensators) Developed by Dr. A. M. Sharaf

19. Switched Modulated Power Filters and capacitor Compensators Economic Tuned-Arm Power Filter and Capacitor Compensator Scheme (used in S-phase 2 wire loads) • Motorized Inrush Loads • Water Pumps • A/C • Refrigeration • Blower / Fans Switched Capacitor Compensator Scheme (used for on/off Motorized loads)

20. Novel Dynamic Tracking Controllers (Family of Smart Controllers Developed by Dr. A. M. Sharaf) • The Dynamic Control Strategies are: • Dynamic minimum current ripple tracking • Dynamic minimum current level • Dynamic minimum power tracking • Dynamic minimum effective power ripple tracking • Dynamic minimum RMS source current tracking • Dynamic maximum power factor • Minimum Harmonic ripple content • Minimum reference harmonic ripple content

21. Novel Dynamic Controllers Dynamic Minimum-Current Ripple tracking Dynamic Minimum-RMS Current tracking

22. Novel Dynamic Controllers Dynamic Minimum-ower Tracking Minimum Harmonic Reference Content

23. Switching Devices (on/off or PWM) The solid-state switches (S1, S2) are usually (GTO, IGBT/bridge, MOSFET/bridge, SSR, TRIAC) turns “ON” when a pulse g(t) is applied to its control gate terminal by the activation switching circuit. Removing the pulse will turn the solid-state switch “OFF” TS/W=1/fS = (ton + toff) 0<ton<TS/W ------The choice of on/off or PWM-switching depends on load time constants/dynamic behaviour (fast/slow dynamics)

24. Switching Devices – PWM Circuits (1) PWM Circuit (Developed by Dr. C. Diduch) for use with Matlab/Simulink (2)

25. Concept of Modulated Power Filters (MPF) Laplace Transform (VF)= (Vm sin (t+)[u(t)-u(t-to)]) ZF(s)IF (s)= (Vm sin(t+) [u(t)-u(t-to)]) The Linear Combination of two Unit Step Functions to describe a Pulse of Amplitude 1 and duration t0. Tune Arm Filter layout

26. Concept of Modulated Power Filters Magnitude and Angle of YF(jw) Frequency Response of the Tuned-Arm Filter with Varying Filter parameters R, L, C and Fixed Duty Cycle αD=ton/Ts/w Frequency Response of the Tuned-Arm Filter with Fixed Filter parameters R, L, C and Varying Duty Cycle αD

27. Modulated Tuned Arm Filter (Sym. & Asym.) • Load is either: • Symmetrical Arc Type • SMPS • Adjustable Speed Drives • Asymmetrical Arc-type • Dynamic Controller: • -Min. effec. Power • RMS current tracking • Min. Harmonic Content Single Line Diagram of System and Modulated / PWM Tuned-Arm Filter

28. Modulated Tuned Arm Filter with (SMPS) Load Without (THD=74%) With (THD=9%)

29. Modulated Asymmetrical Tuned-Arm Filter Without (THD=42%) With (THD=14%) With (THD=7%) Without (THD=18%) Nonlinear Temporal Load Parameters: R1=R01+R11sin(wr1*t); E1=E01+E11sin(wr2*t); R2=R02+R22sin(wr1*t); E2=E02+E22sin(wr2*t); R2= R1(1+) R01=8 R02=12 R11=2 R22=6 wr1=15 E2= -E1(1+)E01= 46 E02=70 E11=12 E22=35 wr2=5 Dynamic Controller: Dual loop of RMS current tracking and Min. Harmonic Content

30. Double (dual) Tuned Arm Filter Without (THD=45%) 3rd Harmonic: C1=50uF; L1=18mH; R1=1 Ohm 5th Harmonic: C2=60uF; L2=5.4mH; R2=5 Ohm With (THD=9%)

31. Double- (dual) Tuned Arm Filter (Two TAF in parallel, different wn1, wn2 tuned frequencies) Without (THD=12%) With (THD=6.5%) Quality factors, Q1 and Q2 can be either: sharp Q=50-100 or wide Q=10-50

32. Modulated C-Type Power Filter • SMPS • Modulated Converter (α) Rectifier firing angle/control : 3º < α < 85º Dynamic Controller:Current ripple tracking and Minimum current level

33. Modulated C-type Power Filter Flickering Without Filter current & voltage With Flickering

34. Hybrid MPF and SCC (new dual Purpose Design) • Arc type Symmetrical • Magnetic Saturation type • Modulated Converter type ZF(jw) at different parameters Magnetic Saturation type • Dynamic Controller: • -Min power ripple • Min. Harmonic Content • Power/Energy Savings Parameters are selected for the dominant task of energy/power savings or harmonic filtering

35. Hybrid MPF/SCC (Magnetic Saturation) IF VF Without (THD=22%) With (THD=9%) Filter Voltage and Current

36. Hybrid MPF/SCC for (Arc Symmetrical-Type load)

37. Hybrid MPF/SCC (Arc Symmetrical-Type) Load Voltage Supply Current Supply Current Without (THD=16%) Without (THD=40%) With (THD=11%) Filter Voltage and Current PWM + Controller Outputs Load Voltage With (THD=7%)

38. Switched Capacitor Compensator with Arc-type load • Arc Symmetrical Type • Cyclical Motorized Type • Temporal Time-Dependent • Dynamic Controller: • -Min. Power ripple • Min. Harmonic Content

39. Switched Capacitor Compensator Supply Current Supply Current Without (THD=40%) With (THD=12.5%) Load Voltage Load Voltage With (THD=8%) Without (THD=16%)

40. Novel Blocking Capacitor Circuit • Inrush Start/Stop current in industrial motorized load draws a high dynamic current reaching 300- 500% of rated current, and this current is dissipated as extra heat through the motor stator and rotor windings and over time, can come to damage motors due to either insulation failure or damage. • Reducing this inrush motor currents can increase the motor life-span by (50-70%; 7-10 years) lowering any heat buildup in the motor and connected cables, particularly for motorized type loads with a frequent (start/stop) load requirements such as blower/ventilation, water-pumping, air conditioning, refrigeration units, chillers, saw mills, etc. • Frequent Start/Stop can cause severe voltage-drops, lighting flicker, voltage-dips and excessive sags that could be magnitude sufficient to affect computerized automatic data processing devices, in particular when the electric grid system is co-feeding large number motorized loads with frequent starting and stopping regime such as water pumping stations.

41. LPF ON or OFF signal to SSR / GTO Threshold delay I0 reference = Iaverage Novel Blocking Capacitor Circuit Simulink Model of The RMS Controller (ON/OFF control) (I) Simulink Model of The Dynamic Average Power Controller (ON/OFF control) (II)

42. Novel Blocking Capacitor Circuit Without Inrush Inrush RMS-value With RMS-value

43. Laboratory Prototype Testing – set up Single Line Diagram TAF or C-Type Filter Topology and Semiconductor Switch

44. Laboratory Prototype Testing (Analog Dynamic Current Tracking Controller – Dr. A,M, Sharaf)

45. Laboratory Prototype Testing DC Power Supply Circuit • Nonlinear Loads Used: • Switch Mode Power Supply (computers) • Temporal Nonlinear Load (Blower/Vacuum/Fan/Air Conditioner • The laboratory test instruments used are the Fluke 43 – (Power • Quality Analyzer) and • the Fluke 97 – (Scope-meter). (Borrowed From NB Power)

46. Laboratory Prototype Testing Test Set-Up for the witched/Modulated Power Filter

47. Laboratory Prototype Testing Without With V, I, F RMS value V, I, F RMS value KVA, PF, DPF, F KVA, PF, DPF, F

48. Full Unified Matlab/Simulink Model (Switched Capacitor Compensators)

49. Full Unified Matlab/Simulink Model(TAF or C-Type Filter

50. Power Filter Design and Selection (Selected Procedure) • The best power filter design usually target any detrimental effects caused by harmonics and waveform distortion. However this ideal filter realization is unrealistic for both technical as well as economical cost reasons. It is very difficult to estimate in advance the level, type or propagation of harmonics (deterministic or probabilistic) throughout the a.c. network and also it is uneconomic to try to cancel all unwanted harmonics. • A practical power filter design criteria usually targets the lower-order dominant offending harmonics to an acceptable level and not to completely eliminate all harmonic orders. • The size (Qc) and quality (factor, tuning frequency) of any power filter are normally the basic specified design parameters. The size of a power filter is defined as the reactive power that the power filter capacitor supplies at the fundamental frequency (f1). The quality of the power filter (Q) determines the tuning-sharpness of power filter.