Our Approach to Power Quality Solutions

Here at InPhase we consider "Any event related to the electrical network which ultimately results in financial loss" a Power Quality Problem. Over the years we have built a team of Power Quality Engineers which specializes in providing custom solutions for your Power Quality requirements and problems. In today's Competitive World a lot of industries are facing productivity issues and dealing with high energy costs. Power Quality Problems are one of the major factors contributing to a lot of downtime, Equipment damage/failure, Increased Energy bills in Industrial as well as Commercial installations thereby leading to loss of productivity and money.

It is estimated that interruptions due to poor power quality amount to losses of 4% of the turnover for the industrial sector. The reported losses are higher for industries which rely on continuous production. The increase in operational costs to compensate for poor quality build up substantially due to damage to operational equipment. With energy costs soaring higher, it is important for the industrial sector to push for better power quality to avoid these compounding losses.

Our Approach to Power Quality is modelled to provide a viable holistic solution to your Power Quality Problems.

  • Identify the phenomena

  • Identify the underlying cause of the phenomena

  • Analyse the problems created in the system due to it

  • Identify the available solutions

  • Selection of a viable solution

  • Analyse the benefits of addressing the Power Quality Problems

  • Selecting a product that fulfills your Power Quality requirements

Want to know more about our Power Quality Solutions ?

Common Power Quality problems

Reactive Power

Reactive power contributes to the field excitation in loads and voltage regulation in the bus. Reactive power contributes to the current drawn from the utility but does not contribute to the “useful work”.

Reactive power creates a lot of anomalies in the system which affect Power Quality in the following ways :

  • Direct Billing effect/ Penalty by the Utility Authority
  • Generator Capacity Reduction
  • Transformer Capacity Reduction
  • Cables Heating / Capacity Reduction
  • Voltage Drops/ Peaks
  • Flicker

InPhase Active Filter is capable of compensating dynamic reactive power instantaneously. Using CT feedback from LT or HT bus, the compensation can be carried out at LT. For HT compensation, a step-up transformer must be utilised.


Harmonics can be defined as sinusoidal voltage or current waves whose frequencies are integer multiples of the fundamental frequency (50Hz or 60Hz). These cause distortion of load current and voltage which can affect the functioning of connected loads.

Some problems that may arise due to harmonics:

  • Overheating of transformers, motors and cables
  • Thermal tripping of protective devices
  • Logic faults of digital devices
  • Capacitor overloading
  • Neutral overheating
  • The life span of many devices is reduced by elevated operating temperatures.

InPhase is a specialist in catering to harmonics mitigation solution. InPhase has a wide range of 2 Level as well as 3 Level Active Harmonic Filters, which can bring down the current harmonics to IEEE519 limits.


Voltage unbalance (or voltage imbalance) is the phenomenon where the voltages at the individual phases of a 3-phase system are not uniform.

Any voltage unbalance may contribute to premature equipment aging. Unbalance causes

  • Power supply ripple
  • Severe insulation degradation due to heat generation
  • Decreased mean time between failure (MTBF) on all affected equipments
  • Poly-phase induction motors should not be operated with an unbalance greater than 5%

InPhase has IGBT based solution which can compensate for the negative sequence current, which is the cause of unbalance. By eliminating the negative sequence current, InPhase IGBT based converter can balance any L-L unbalance in the system.


Transients or Surges are high magnitude transient waves of voltage, current or power in the electrical sytem caused by lightning, switching, magnetic and inductive Coupling, static Electricity etc.

Effects of transients on the system:

  • Degradation of Insulation, Circuit Breakers, Switches
  • Equipment Malfunction/Damage
  • Equipment Heating
  • Nuisance Tripping
  • Increased Hysteresis Loss in Motors
  • Transformer Efficiency Reduction

InPhase provides custom solutions for transients based on the Power Quality Study.

Voltage Dips and Swells

Voltage dip or sag is defined as the decrease of the voltage level to 10% - 90% of the rms voltage for a duration of 0.5 cycles to a few seconds. Voltage swell can be defined as the increase of the voltage to 110-180% of its rms value for a duration of 0.5 cycle to a few seconds.

Effects of Voltage Dips and Swells:

  • Temporary dimming/flickering of lights
  • Breakdown of Power Supply Components of Equipment
  • Control Problems and Hardware Failure in Equipment
  • Equipment Damage

Dynamic Voltage Restorer (DVR) can be used to mitigate voltage sag as well as voltage swell. DVR is a series connected equipment which can dynamically control the output voltage.


Flicker is a visible change in the intensity or brightness of lighting equipment due to rapid fluctuations in the voltage of Power Supply. Flicker is usually attributed to the switching operations of Industrial Processes( Motors, Furnaces etc.).

Effects of flicker:

  • Damage to Sensitive Equipment
  • Damage to Lighting Equipment
  • Reduced Perception & Annoyance to Humans

InPhase provides custom solutions for flicker based on the Power Quality Study.