Automatic Power Factor Controller

The existing system has some serious disadvantages. You cannot have ideal compensation to reactive power as because of the steps only a near about compensation to Power Factor is available. The System will always be over compensated or under compensated. There exists a fear of over improvement and a name is given to this as ‘power factor correction better than 0.9’. With combination of increments in sizeable capacitor steps, and abrupt full current switching, over improvement could cause over voltages of as much as 40 % on affected power lines and subsequent damage to motor driven equipment under certain conditions of operation.

The capacitor switching is primary cause of trouble in computer receiving power from lines. True in the Capacitive switching circuits, today switching is made at ZERO VOLTAGE CROSSING, but this feature achieves a little because in capacitors, when voltage curve is at zero, the current curve is at peak and vice versa.In the absence of Sensitive Electronic loads, the operation of contactors is a rough & violent physical action – resulting in frequently blowing of fuses. This results in watt losses & in this interim period, the kilowatt demand increases operational expenses until those fuses are replaced.

With rectifier transformer winding, a resonant circuit develops whose frequency closely coincides with frequency of said 5th Harmonic, making the current seriously dangerously uncontrollable.The capacitors work at all time at full rated voltage and at certain switching instances the peak voltage is enhanced beyond the rated peak voltage of capacitors – which can destroy or reduce the life time of these components. Since the switching of multiple capacitors through contactors is involved, plethora of harmonics gets introduced in the line & thereby LINE FILTERS of suitable rating have to be installed. It is like first introducing the NOISES & HARMONICS & then putting circuits & chokes to mitigate their evil effects