DESIGN AND IMPLEMENTATION OF THYRISTOR BASED AUTOMATIC ON LOAD TAP CHANGER FOR CONSTANT OUTPUT VOLTAGE USING ANN & IOT
Abstract : The on-load tap changing (OLTC) regulators have been widely used in various industry. The main function of OLTC is to change the turns of transformer winding, so that the voltage variations are limited without interrupting the secondary current. In other word the voltage can be regulated with the changer without any supply interruption using ANN controller.
The Power quality is essential prerequisite of todays required load. Power system has been facing many problems due to variation in loads. Conventional on load tap changer (OLTC) is being used since long time for any momentary changes in load requirement. Conventional tap changers uses mechanical switches for tap changing.
Mechanical tap changer has some drawbacks, like they takes more time for operation, arching, mechanical losses, manpower required, continues maintenance. Also sometimes mechanical tap changer get stuck between two taps, which leads to damage of whole system, it affects stability of the system etc
The remote monitoring of OLTC internet system is a system that could be used for the real-time data monitoring of transformer through internet of things(IOT)
Tap changer is connection point selection mechanism along a transformer winding which allows a variable number of turn selected for obtaining output voltage according to load condition.
Problems in mechanical oltc are arcing problems between contacts, mechanical wear and tear due to frequent use. Require regular maintenance and service, noisy operation.
Transformers isolate the primary input voltage from the secondary output voltage using electromagnetic coupling. Electrical isolation between an input source and an output load using just light by using a very common and valuable electronic component called an Optocoupler.
This proposes to Design of Solid-State On Load Tap-Changer for Transformer using semi conductor devices like as Thyristor using ANN control & MATLAB/Simulink Software.
This problem addition of power electronics devices in circuit then the performance of the systems drastically changes.
When output voltage of load changes this changed voltage sensed by the devices connected to output terminal ‘voltage sensing device’ and provide this data to comparator. Comparator is the device which connected in the intermediate between the input supply ‘voltage sensing device’ to output ‘voltage sensing voltage.
So it compare voltage and active the isolating device which turn on the Thyristor semi-conductor device and then this semiconductor device adjust the taps according to the output voltage which is totally automatic operation.
Online monitoring using IOT
On Load Tap Changer are used since many years ago. For voltage profile regulation change primary tap according requirement of under input voltage variation in conventional tap changer there are many problems like arcing, high maintenance, slow response time, wear and tear is high so this is big challenge to remove that drawbacks with the automatic voltage contract OLTC.
By using Thyristor, MOSFET, GTO, IGBT and the controlling device by using of this automatic voltage OLTC adding taps this increases efficiency and system is steady after large changes of voltage.
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