Power Quality and Harmonics

 

Power Quality ......What is it?

Table 1. Power Quality Problems / Solutions

POWER QUALITY CATEGORY	TYPICAL EFFECTS AND PROBLEMS	MEASUREMENT METHOD	TYPICAL CAUSES	TYPICAL CONDITIONING SOLUTIONS
Transients	Random equipment failures Computer data errors	Peak Hold Rise Time Pulse Duration	Lighting ESD Load switching	Surge arrestors Isolation Transformers Filters LVC Conditioners
Sags/Surges Slow >100ms	Computer data errors Power supply failures.	Peak/Through Hold Pulse Duration	Load switching Lifts Industrial equipment Motor starting	Voltage Stabilizers Ferroresonant Transformers
Dropouts/Surges Fast < 30ms	Lighting flicker Computer data loss Random equipment resets/errors	Peak/Trough Hold Pulse Hold	Load switching Fuse clearing Arc furnaces	Electronic Voltage Stabilizers Ferroresonant Transformers Mains Voltage Compensators
Under/Over Voltages	Motor torque reduction Motor overheating Motor burn out Circuit breaker tripping Power supply failure	RMS Vs Time Statistics Waveform Peak/RMS	Industrial sites System overload Load shedding Tap changing	K-factor Transformers Ferroresonant Transformer Voltage Stabilizers Mains Voltage Compensators
Voltage Flicker	Lighting problems/flicker Transformer noise Computer data loss Monitor screen wobble	Flicker Meter Magnitude/Frequency of occurrence Modulation Frequency	Tap changing Load switching Load variations	Electronic Voltage Stabilizer Ferroresonant Transformers
Harmonic Current Distortion 3 Phase	Neutral cables overheating/fires Transformer burn outs High neutral to ground voltages/circulating currents	THD Spectrum Statistics (3Wire/4 Wire)	Non linear loads Variable speed drives System resonance	Ferroresonant Transformers Passive Filters Active Harmonic Conditioners
Harmonic Current Distortion	Transformers overheating/fires Monitor screen wobble	THD Spectrum Statistics	Non linear loads Variable speed drives	Passive Filter Series/Parallel Ferroresonant Transformer Active Harmonic Conditioners
Harmonic Voltage Distortion	Random equipment resets/crashes Clock problems Synchronizing problems due to multiple zero crossings	THD Spectrum Statistics (L-L) (L-N) (N-E)	High levels of non linear current Variable speed drives System resonance High system impedance	Electronic Voltage Stabilizer (Waveform correction option) Active Harmonic Conditioner
Interruptions Power Failure	Black outs Data loss Network failures Production line down time	Duration against time	Fuse fault clearing Load shedding Lightning (interrupters)	Uninterruptible Power Supplies Back up generators
Bad Power Factor	High maximum demand Over sized supply	kVA/kW kVAR	Motor Loads Lighting systems	Power factor correction Capacitor banks fixed/auto

 

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In order to assist you from your critical power quality situation, we are having a few solutions which might be suitable to restore the situation depend on it's level.

• Blocking Reactor

Please do not hesitate to contact us should you required further assistant.