Page 12 - rise 2017

In general, there are two different methods of Power Factor Correction which are known as
the passive components and active components. Power Factor Correction (PFC) serves by reducing
the harmonic distortion and at the same time increasing the real power level value. To reiterate, the
value of real power level can be increased simply by improving the current shape input. Linear load or
also known as the simplest resistor is the most ideal electrical appliance used in minimizing the losses
in other devices with the same source compared to the reactive load. This is because the reactive load
may have an erroneous power supply switching. Besides, low power factor can be compensated by
using either passive or active devices. Electrical motors are the easiest example to represent the loads
that is needed to improve the power factor since it is known as having the highest inductive load with
the availability of loads. The correction can be made by using the capacitors to counter the circuit.
However, the entire system is not that easy as many circuit designers need to take into consideration
about this matter by not introducing any resonant into the system. Other than that, an adaptive scheme
connected to the reactive elements need to be implemented to the variable power factor and to the
high powered machinery. At this juncture, it is also important to note that the cost components, space
and efficiency in accommodating the specific power rating bands to the design must also be well-
considered.

Passive Power Factor Improvement
A passive component such as diode is used in the converter for the passive power factor improvement.
In this case, the converter is a bridge rectifier, in which the device functions in converting the
alternating current signal weather voltage or current signal to direct current signal [5]. Theoretically,
by using this approach, the power factor can be increased to a value of 0.7 to 0.8. By increasing the
input voltage value, the power factor values will become higher. The function of passive power factor
improvement is similar to low pass filter, in which it will filter out all the harmonic contents in the
circuit. However, the passive power improvement can only be improved within a value range between
0.7 and 0.8. The value should not exceed 1.0 as it can decrease the wave current within the standard.
The advantages of using this method are described below:
i. Simple and easy to implement
ii. The components are rugged and cheaper
iii. The circuits does not generate in high frequency
iv. The modified circuit only focuses on filter and rectifier circuits.
v. Easy to install

Even though this method offers a wide range of advantages, but it still need some
improvements. The improvement criteria that need to be considered are described below:
i. To achieve the best performance of power factor, there is a need to increase the filter
dimension.
ii. The voltage efficiency is poor if it still contains ripple and distortion.
iii. A relationship between the inductor and capacitor may trigger the resonant at difference
frequencies.
iv. The value of magnitude at fundamental harmonic may get phase shifted excessively and cause
the value of power factor decrease.
v. The shape of waveform depends on the types of loads whether better or worst.

Active Power Factor Improvement
An active power factor improvement is an innovation from passive power factor improvement. An
active approach is the best way to improve the power factor correction in electronics appliance. This
design is aimed to control the amount of power produced from the loads and obtain the value of
power factor close to unity. Generally, the active components serve in controlling the current input of
the loads which is similar to the waveform voltage (perfect sin wave) [6]. Besides, the components
can reduce the content of harmonic and distortion by combining the reactive elements or using active
switches such as MOSFET, CONTROL IC and others. The advantages of these methods are described
below:
i. The device is in smaller in sizes and very light in weight
ii. The value of power factor can increase over 0.95