In this project we have tried studying about nature of industrial load, designing of a PF corrector for the same and Development of a single phase PF corrector using PIC microcontroller chip. Using PIC microcontroller and sensors it measures and senses the PF of the load. With the help of programming done right it will determine and switch appropriate number of capacitors to compensate the reactive components of the electrical load. Thus, driving a Power Factor value to unity results in higher efficiency and reducing the maximum demand.
Exposure to construction of manual and automatic Power Factor Correction apparatus is also imparted at DDK (DoorDarshan Kendra) and BSNL (Bharat Sanchar Nigam Ltd.) Sub Stations.
In earlier times the loads have been fairly benign, having either resistive characteristics (light bulbs) or input currents that are sinusoidal but phase shifted (AC Motors). Most electronics systems now use one or more switch mode power converters that will tend to draw currents from the power line in a non-sinusoidal fashion. This input current characteristics results in current & possibly voltage distortions that can create problems with other equipment connected to the power lines & degrade the capability of the mains. In electrical plants the loads draw network electrical power as power supply source or convert it to other form of energy or into mechanical output. To get this, it is often necessary that the load exchanges with the network, the reactive energy, mainly of inductive type. This energy if not immediately converted into other forms, contributes to increase the total power flowing through the electrical network, from the generator along the conductors, to the users. To smooth such a negative effect, the power factor correction obtained by using capacitor banks to generate locally the reactive energy necessary for the transfer of useful electrical power, allows a better & rational technical- economical management of plants.
In our work we aim to improve the overall power factor of an installation. Improving power factor means taking necessary steps to increase the power factor in a defined section of the installation by locally delivering necessary reactive power so that the value of current & consequently of the power flowing through the upstream network can be reduced, at the required output power. Our work provides a solution which allows technical & economic advantages.
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