10-06-2017, 07:07 AM
the circuit diagram of microcontroller based tap changer of transformer
The main purpose of this Microcontroller Based Semiconductor Tap Changer For Power Transformer project report is to provide a fully electronic tap water changer. Triacs transformer. Microcontroller as a switching device on selected tap the power of its software design are used to acting as a catalyst for the triac, in turn, loaded. Step down and the opt-coupler is connected between the input and each isolated from the microcontroller connected to low voltage connected to the microcontroller from the damaging high-voltage transformer.A prototype fully electronic semiconductor under load tap changers for power transformers has been designed and built. With the advent of high performance semiconductor devices with mechanical problems on the fixed-position switch has been properly brought together. In this work the prototype with a triac as the switching devices and microcontroller as the triggering circuit has been built. The result of this work has shown that the prototype fast response time of about 0.44 s to respond will receive each load change. It also produces no cross-border problems, as there is no mechanical contact and requires no maintenance and can swell to be considered as one of the quick fixes the voltage dip or voltage. The system is tested for reliability and proves to be the output voltage of the system to maintain. Owing to the constraint of time the wiring layout can be optimized in future by designing a planned wiring layout to avoid any interference between power and control circuits.Power quality is one of the most talked about topics these days. Both the power utilities and customers are quite concern with the quality of the power supply, whether it be the power generated by the power utilities or the power consumed by the customers respectively. They need these supplies to be at its optimum value so that the cost is efficient; otherwise problems such as over voltage, under voltage, voltage swell, voltage sag, noise and harmonic caused by the disturbances in power supply could be disastrous. Several methods have been suggested and applied as the solution to these problems. One of the methods is by employing on-load power transformer with tap changer, where the output voltage of the power transformer remains constant irrespectively to the input voltage or variation of the load. The existing mechanical on-load tap changing power transformer has few disadvantages, as it is slower, produces arching each time the tap setting is changed and needs regular maintenance. With the emergence of high power semiconductor devices such as triac, problems associated with the mechanical on-load tap changing power transformer have been properly rectified. In this study, a small prototype consisting of triacs as the switching devices and microcontroller as the triggering circuit has been constructed. The results obtained from this study show that the prototype has a faster time response of approximately 0.4s for the circuit to react to any load changes, produces no arching problems as it has no mechanical contact and requires no maintenance. The system has been tested for reliability and proven to be reliable in maintaining the output voltage of the system.
Conclusion:
A prototype of fully electronic on-load tap changer has been built and tested. Triac devices as the switching device that had eliminated all disadvantages of arching, contact wear and maintenance that associated with conventional mechanical tap changer. With these semiconductor devices and microcontroller as the processing element, the response time of the tap changer had been improved to approximately 0.44s. The result obtained from the experiment had showed that the tap changer was able to maintain output voltage level by varying the tap setting each time the input voltage changes.