Engineering, 20.04.2020 10:20 beetle1234

A 230 V, single-phase supply feeds the following loads: (a) incandescent lamps taking a current

of 6 A at unity power factor; (b) fluorescent lamps taking a current of 5 A at 0.75 leading power

factor; (c) a motor taking a current of 7 A at 0.7 lagging power factor. You are required to

correct the power factor to unity.

a) Show how it can be achieved by connecting a parallel reactance to the load

- provide the phasor diagram based on computed branch currents; and the power

triangles before and after power factor correction.

- provide the appropriate kVar rating of reactance, and if it’s a capacitor bank compute

the capacitance or if it’s an reactor (inductor) compute the inductance.

b) If it is proposed to use series reactance to perform power factor correction, show how this

can be achieved and comment on this approach.

d) Verify your answers using Matlab/Simulink

- show the rms currents on the Simulink model

- Plot the instantaneous branch currents and show clearly how the phase angle between

the supply voltage and supply current changes, accordingly

Answers: 1

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A 230 V, single-phase supply feeds the following loads: (a) incandescent lamps taking a current

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