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Member Since 07 Nov 2006
Offline Last Active Aug 19 2007 01:21 PM

Topics I've Started

Pf Control Relay

09 December 2006 - 11:24 AM

Hi !! I have a question regarding power factor control relay. As you know these relays can sense the power factor and switch on or switch off the capacitor banks to achieve required power factor. This relay gets current input ( may be through CTs ) and voltage input ( may be through PTs ). My questions is: In orer to calculate the system PF and control capacitor banks accordingly, does the MAGNITUDE of the current signal and voltage signal is of any importance or the relay will ignore the actual values and just see what is the phase angle between current and voltage?



Power Factor Correction Using Synchronous Motor.

09 November 2006 - 04:21 PM

Hi ! I am Milind

If a plant has a fairly big ( > 2 MW ) syn. motor , how can use it to improve the overall power factor of the plant ? What data should I ask the motor manufaturer for this purpose?

Thank a lot.

Power Factor Corretion For Generator

09 November 2006 - 04:17 PM

Hi ! I am Milind. I have two queries regarding Generators and PF.

1. Does a captive power plant, consisting of several generators ( GTG or DG ) in parallel, require power
factor correction ? I mean , if the plant PF is around 0.8, that should be OK, is it not ? Is there any
overwhelming need to apply PF capacitors to improve it further ?

2. Suppose , if above CPP is runing in parallel with grid supply, can I control generator excitation so that
almost all the kVARs required by the load are supplied by the generators and I do not import any kVARs
from the grid thereby maintaining grid PF to almost unity ? This way, I do not require any capcitors and
I do not pay any penalty due to poor PF of the grid.

Thanks a lot and regards,