# Power factor consideration



## Shimon (Mar 24, 2012)

Hello all 
I`m new at this forum and this field...
Today I work on a project that involve planning of a electrical grid to feed charging station of electrical vehicles I stady this field very hard and love it. 
I have one question I hope its the right place
In the planing of the grid I bump into a small problem that I hope that you will help me with this.
I need charging station that feed on 230V and uses IEC 62196 EV type 2 connector.
I look over few data-sheets of charging stations and I noticed that while they worte on there specifications input voltage and current are 230 Vac @ 16A, the AC charging power output is 3.6[Kw].
that means the electrical car charging is with power factor of 1 if not so in whice power factor the charging take place?? 
If the charging take place with another power factor (<1) so to get to the power output of 3.6[KW], I will need to provied higer current to the charging station for compensate the reactive power in the grid so I will need thicker wires for the new current.
I hope that I expleain my problem well.


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## DJBecker (Nov 3, 2010)

Shimon said:


> I need charging station that feed on 230V and uses IEC 62196 EV type 2 connector.
> I look over few data-sheets of charging stations and I noticed that while they worte on there specifications input voltage and current are 230 Vac @ 16A, the AC charging power output is 3.6[Kw].
> that means the electrical car charging is with power factor of 1 if not so in whice power factor the charging take place??


A "Charging Station" is mostly just an A/C power outlet. The internal electronics only need to control a relay and consume little power, so they have negligible effect on the power delivered.

The only directly useful power information is the 16 amp maximum. The 3.6KW figure is a marketing number. If the charger has a low power factor, it is still limited to drawing 16 amps, not 3.6KW. Thus you can safely size your supply wiring using that current as the true maximum.

This will change slightly when advanced charging stations deliver DC power. The charging station will become responsible for rectification, power factor correction and voltage regulation, and the charging station type will have an impact on the power supply wiring requirements. But it's a safe guess that they will all be above 95% (combined power factor and rectification efficiency) at maximum load.


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## Shimon (Mar 24, 2012)

Ok, thank you very much.
Its what I about "marketing number".

Did EV include in them any kind of power factor correction?
I asked that because: 
if I have electrical cars that charge through my commercial grid so I need to add power factor correction? like with electrical engines that we add capacitors for PF correction. 
OR the car came from the manufacturer with corrected PF?


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## Brute Force (Aug 28, 2010)

My understanding is that all commercially available power supplies larger than 75 watts are required to be power factor corrected. That includes EV battery chargers. Check the specs before you make a purchase, but it's something I'm pretty sure you won't have to add on externally.


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## Shimon (Mar 24, 2012)

TNX...
That what I`m donig look for the spec, but I don`t found one yet.


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## jaspersk (Jun 26, 2008)

Brute Force said:


> My understanding is that all commercially available power supplies larger than 75 watts are required to be power factor corrected. That includes EV battery chargers. Check the specs before you make a purchase, but it's something I'm pretty sure you won't have to add on externally.


I don't believe this to be true. While the more sophisticated chargers have active PFC (Elcon, Manzanita, Zivan, Brusa, etc), many of the cheaper chargers do not. They may have some capacitance for some passive correction but I am certain from experience that there are chargers that have fairly poor power factor (under .85). Often those cheaper chargers won't include a spec for power factor in their literature so you need to ask or measure it.


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## DJBecker (Nov 3, 2010)

Shimon said:


> Ok, thank you very much.
> Its what I about "marketing number".
> 
> Did EV include in them any kind of power factor correction?
> ...


Even if they have a poor power factor, they are limited to drawing 16 amps. That means they will draw less than than the full amount of power available.

There are various national mandates for more efficient and better power factor supplies, but it's still pretty easy to find loopholes and thus crude supplies. My guess is that since commercial EV chargers are evolving rapidly, they all will soon have near-unity power factors to meet the regulations.


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