Power electronics is an interdisciplinary technology used to change the characteristics of the electrical power circuit – such as voltage, current, frequency and magnitude that suit for a particular application. Power electronics can be applied in different areas: medical equipments, transportation and utilities including different sub systems like solid state transformer, line transformer, solid state circuit breaker; and, consumer products like telecommunication equipments, appliances, lighting systems, industrial and commercial devices and equipments.
Power electronics is also a subject relevant to research for electrical and electronic engineering that deals with design, control and computation of non-linear time variant electronic systems. Power electronics plays a leading role for modern technology by acting as a hub of power and energy control. Most of the consumer electronic devices make use of the AC-DC converter as a power electronic device in many battery chargers and personal computers.
The building blocks, as shown in the above power electronics block diagram, are input power, output power, power processor and controller. From the source to the load, the electrical energy is converted from one form to another depending on these specifications: efficiency, availability, reliability, affordability, size and weight.
The following list of advanced electrical projects that are based on power electronics can be used in a wide range of applications.
- ACPWM Control of Induction Motor
- Thyristor Controlled Power for Induction Motor
- Electronic Soft Start for 3-Phase Induction Motor
- Three-phase Solid-state Relay with ZVS
- FACTS by SVC (flexible AC transmission)
- Remote AC Power Control by Android Application with LCD Display
- UPFC Related Display of Lag and Lead Power Factor
- Industrial Battery Charger by Thyristor Firing Angle Control
- RF Based Home Automation
- Industrial Power Control by Integral Cycle Switching Without Generating Harmonics
From the above list, a few of the selected projects are described below in detail:
ACPWM Control of Induction Motor
This project is designed to implement a new speed-control technique for a single-phase A.C. induction motor, which represents the design of a low-cost and high-efficiency drive capable of supplying a single phase A.C to an induction motor with a PWM sinusoidal voltage.
A microcontroller is used as a central processing unit to control the speed of the induction motor which is proportional to the frequency. The working of this project is explained with the help of a block diagram, as shown below, which consists of a power-supply block to power the entire circuit, and a zero-detection block to convert the sine pulses into square pulses. Furthermore, the block diagram also includes load arrangement with a bridge rectifier, which is switched on by using OPTO isolators and IGBT.
The above circuit consists of a power-supply circuit that supplies power to the whole circuit, and a zero-detector circuit, which is interrupted with the microcontroller that converts the sine pulses into square pulses from a low range to a high range at regular intervals. At some specified frequency in cycles per second, the voltage applied to the load is varied from zero to a maximum value, and simultaneously uses pulse-width modulation technique and produces lower high order harmonics when compared to the single phase angle control used for triacs.
The input of the rectifier is connected to the load, whereas the output is connected to the power transistor that includes IGBT, MOSFET and OPTO isolator. If the power transistor is off, then the current cannot flow through the bridge rectifier, and the current across the load also remains off. In the same way, if the transistor is on, then the current flows through the bridge rectifier and across the load; and therefore, by changing the PWM pulses, the power of the load is controlled and PWM pulses are synchronized with the supply voltage by zero voltage sensing points. This new technique can be used in consumer and industrial products such as dish washers and ventilators.
Industrial Power Control by Integral Cycle Switching without Generating Harmonics
This project is designed to achieve an integral cycle switching – a method used to remove whole cycles or portion of cycles of an AC signal. It is an old technique used for controlling the AC power and linear loads across the heaters used in electric furnace.
A power supply circuit is used to control the whole circuit by a DC power supply. It is very precise to achieve the concept of cycle stealing of voltage by using a microcontroller, which is programmed by using C language.
A comparator is used as a zero crossing detector for generating sine pulses, and it is fed as interrupt to the microcontroller. The comparator delivers the output based on the interrupts it receives and generates triggering pulses. Based on these pulses, it is easy for triggering the OPTO-isolators based on the TRIAC to achieve the integral cycle as per the input switches interfaced to the load as the output in place of the series motors.
The voltage and current varies at infinite duty cycles or three cycles. The current may be high when the power transistor is on, and it may be completely off at some interval of triggering pulses. The output wave forms of the triggered pulses can be displayed on the LCD display which is connected to the power transistor circuit.
Electronic Soft Start for a 3-Phase Induction Motor
The project is designed to provide a soft and smooth start for a three-phase induction motor. The 3-phase induction motor provides higher current, more than its capacity, and the motor reaches its full speed; this may result in stressing the windings of the motor, and eventually may collapse the windings of the motor.
The block diagram, as shown above, consists of six silicon-controlled rectifiers that are connected in twos for the three-phase induction motor, and also connect a set of lamps for representing the coils of the three-phase induction motor. The comparators are interfaced with the capacitors are used as a control unit to perform the charging and discharging action, which results in firing the pulses, which can be reduced gradually based on the full speed of the motor.
The voltage of the motor will be low at some intervals and will be high at peak range. The motor starts slowly and finally picks up speed for its safer operations.
This is all about the advanced power electronic projects that can be used in different applications such as transportation, medical equipments, etc.We appreciate the efforts of our readers for their valuable time on this article. Apart from this, for any help regarding any projects, you can contact us by commenting in the comment section below, and also contact us for any help regarding any project or similar sort of projects.