Power Quality is a significant issue which is usually left unattended at most of the MSME units of our country. The consumer of electrical energy requires electric power with a certain quality, but loads can have a negative impact (or act as pollutants) on the electrical system and are thus also subject to an assessment in terms of quality. Power quality is therefore intrinsically linked to the interaction between the electrical system and loads and one must take into account both the voltage quality and power quality.
Possible consequences of low power quality that affect business costs are:
Power failures (Release switches, fuses blowing).
Breakdowns or malfunctions of machines.
Loss of saved data and operational settings in memory units.
Overheating of machines (transformers, motors, etc.) leading to reduced useful life.
Damage to sensitive equipment (computers, production line control systems, etc.).
Electronic communication interference.
Increased distribution system losses.
The need to oversize systems to cope with additional electric stress, resulting in higher installation and operational costs.
Safety issues due to possibility of bursting cables and flash in connections.
Interruption of production due to these impacts of low power quality entails high costs due to production loss and the associated waste. The impact of production interruptions is greatest in companies with continuous production.
Among the main causes of poor power quality in LT systems are:
Excessive reactive power, because it charges useless power to the system.
Harmonic pollution, which causes additional stress on the networks and systems, causing them to operate less efficiently.
Voltage variations, because equipment operates less efficiently.
The solutions vary for each cause. Excessive reactive power is regulated by a power factor correction system, which not only avoids any penalties due to excessive reactive energy, but reduces the “unnecessary” electrical current that flows into the lines and power components, yielding substantial benefits, such as reducing voltage drops along the lines and leakages due to the Joule effect. Harmonic pollution is caused by large amounts of non-linear consumption (from inverters, soft starters, rectifiers, pow
er electronics, non-filament lighting, presses, etc.). Such devices deform the electrical current causing disturbances and problems to the system. Harmonic pollution is solved by active filters that are capable of eliminating the current harmonics in the system by measuring and injecting the same current, but in the opposite phase. The voltage variations can be reduced with a voltage stabilizer, which ensures a voltage output at a nominal value. Reduced productivity, loss of data, loss of security, and machine breakdowns are only some of the problems caused by an unstable power supply that can be solved with a voltage stabilizer. Proper treatment of the power quality is utmost necessity for long term failure proof operation of the production system is the need of time and shall be highlighted and made mandatory by law if deemed fit by authorities.