What is Power factor?

Power Factor is a measure of how effectively incoming power is used in your electrical system and is defined as the ratio of Real (working) power to Apparent (total) power. 

Real Power (KW) is the power that actually powers the equipment and performs useful, productive work. It is also called Actual Power, Active Power or Working Power.

Reactive Power (KVAR) is the power required by some equipment (eg. transformers, motors and relays) to produce a magnetic field to enable real work to be done. It’s necessary to operate certain equipment but you don’t see any result for its use.

Apparent Power (KVA) is the vector sum of Real Power (KW) and Reactive Power (KVAR) and is the total power supplied through the power mains that is required to produce the relevant amount of real power for the load.

Let’s look at a simple analogy in order to better understand these terms. Let’s say you’ve ordered a glass of your favourite beer. The thirst quenching portion of your beer is represented by Real Power (KW). Unfortunately, along with your ale comes a little bit of foam that doesn’t quench your thirst, represented by Reactive Power (KVAR). The total contents of your glass (KVA) is this summation of KW (the beer) and KVAR (the foam). The power factor is the ratio between Real Power and Apparent Power. It’s expressed as a value between -1 and 1 and can be either inductive (lagging) or capacitive (leading). If the power factor is 1, then all of the power supplied is being used for productive work and this is called ‘unity’.

Therefore, for a given power supply (KVA):

„The more foam you have (the higher the percentage of KVAR), the lower your ratio of KW (beer) to KVA (beer plus foam). Thus, the poorer your power factor.

„The less foam you have (the lower the percentage of KVAR), the higher your ratio of KW (beer) to KVA (beer plus foam) and the better your power factor. As your foam (or KVAR) approaches zero, your power factor approaches 1.0 (unity).

What we Use


The Sinexcel SVG represents the latest generation technology in Power Factor Correction solutions. By eliminating the need for switched capacitors and providing dynamic step-less compensation, the SVG is a totally modern solution that offers high performance in a compact package and requires very low maintenance.


Save money on electricity costs

If your billing has changed to a kVA demand tariff and you have poor power factor, you are definitely paying for electricity that you are not using. In such cases, the SVG will reduce your electricity bills.

Typically, most installations achieve savings of 10%-30%.

ROI (Return on Investment)

It makes great financial sense to invest in SVG technology. Typically, our customers achieve a ROI of 6 months – 2 years. After this period, they benefit from on-going cheaper electricity costs permanently.

Reduced Burden on Infrastructure

The SVG reduces heat on the electrical system, resulting in greater longevity and lower maintenance costs.

Can work with & enhance existing Capacitor Bank Systems

If you already have an existing capacitor bank PFC system, you can add an SVG to improve the performance achieved.

Space saving

  • Modular, compact & light weight

  • Takes up minimum real-estate in switch room

  • Can be integrated into switchboard

Easily expandable

  • Just add modules to increase capacity

  • Up to 100kVAr available in a wall mount solution

  • p to 600kVAr available in a single tier cabinet configuration

The Sinexcel SVG operates by detecting the load current on a real-time basis through external CT’s and determining the reactive content of the load current. The data is analysed and the SVG’s controller drives the internal IGBT’s by using pulse width modulation signals to make the inverter produce the exact reverse reactive current of the corresponding load reactive content.

This is injected to the grid to compensate the reactive content of the load current. By adjusting the output voltage amplitude and phase angle or by directly controlling the AC side current, the SVG can absorb or generate VAr according to the load reactive power or the grid voltage level.


Excellent power factor correction performance

  • Can maintain a PF of 0.99 lagging or unity if required

  • Corrects lagging (inductive loads) AND leading (capacitive loads) power factor (-1 to +1)

  • Not affected by resonance

  • Can operate at low voltages

Eliminating the weakest link – the capacitors

The most vulnerable and weakest link in a traditional PFC system are the switched capacitors. Capacitors can leak, rupture or ignite & have life expectancy of 3-7 years, depending on environmental conditions, resulting in high maintenance costs. The SVG eliminates the need for capacitors, resulting in greater longevity and minimal maintenance costs.

Dynamic step-less compensation

Traditional switched capacitor PFC systems have a response time of 20ms-40s, depending on the use of a solid state switch or a contactor. Most units use contactors resulting in a 30-40s response time. They then respond in steps of 50, 25, 12.5 or 6.25 kVAr. 

Therefore, often by the time the unit responds, the power factor has changed and then they inject a fixed quantity of reactive current depending on the step. This results in the system perpetually either under-compensating or over-compensating (chasing the load).

The Sinexcel SVG profiles the load and operates with a response speed of <15ms (Dynamic reaction time is less than 50μs). It is a virtually real-time instantaneous response and it only injects the kVAr that is required in that moment. Therefore, the SVG is never over-compensating or under-compensating.

Corrects load imbalance
Measures all 3 phases and provides specific dynamic kVAr compensation each phase.
We recommend the Sinexcel SVG units, which represent the latest generation of PFC technology.

The older technology uses banks of switched capacitors to improve your Power Factor. However, capacitors typically fail within 3-7 years.

To ensure that these units keep performing optimally, you need regular inspections, parts replacement and ultimately high maintenance costs.

The SVG is a totally modern electronic solution which does not use switched capacitors, provides the highest possible performance and requires very low maintenance.