Description:This invention proposes a power factor correction system integrated with an LC series filter which can mitigate the higher order harmonics caused by the parallel resonance of capacitor banks. The capacitor banks are connected in delta configuration which reduces reactive power losses. The proposed system is microcontroller based which checks the active, reactive and apparent power components from the data i.e. voltage and current measured from the potential and current transformers. The electrical parameters, voltage and current are sensed by respective sensors and measured by respective transducers. The measured analog data is converted to the discrete digital data through an ADC converter to feed the information into the microcontroller for processing the data. A feedback is taken from the fixed capacitor banks which involves switches (MOSFETs or relays). The microcontrollers is programmed in such a way that it switches the capacitors until the required level of power factor is met.

The proposed system involves:
• Power supply module
The module involves a step down transformer to reduce the voltage level from 230 V to 12 V. A bridge rectifier to convert AC voltage to DC along with a capacitor
Filter to reduce the ripples. It also contains a voltage regulator (LM7805CT) to produce variable DC voltage (5V for microcontroller).

• Capacitor banks
The capacitor banks are delta connected in case of 3 phase systems or connected parallel across the load if it is a single phase system. The capacitor banks stores reactive power and provides the residual reactive power required by the load. This reduces reactive power dependency of load from the supply.

• Microcontroller
The microcontroller (ARM or Arduino) can be used to process the data of voltage and current levels and compute the power components and power factor. If the power factor is not met the optimum value the microcontroller automatically switches the capacitor banks to compensate for the reactive power.

• LC filters
Due to parallel resonance from the capacitor banks higher order harmonics are introduced into the system. These harmonics can be fatal on electrical appliances. To mitigate such harmonics an LC filter is integrated with capacitor bank. The LC filters introduces LC oscillation with certain frequency. With proper designing of LC filter the frequency components can be introduced which can nullify the harmonics generated from the capacitor banks.
, Claims:1. The power factor correction and THD Reduction system Comprising:
An highly inductive load rated at 2.5 kW
A microcontroller to process the data
A Capacitor bank
An LC filter circuit
The voltage and current sensor
A power supply module

2. The power factor correction system set forth in claim 1 wherein, the capacitor bank are
Connected in delta configuration.

3. The power factor correction system set forth in claim 1 wherein, The power supply
Module comprise of a rectifier and a voltage regulator.

4. The power factor correction system set forth in claim 3, wherein the rectifier consist of a
Capacitor filter to reduce the ripple content.

5. The power factor correction system set forth in claim 3 wherein, the voltage regulator
Used to control voltage at desired level.

6. The power factor correction system set forth in claim 3 wherein, the LC filter is used to
Produce resonance frequency components to nullify harmonics.