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This Harmonic Analysis of Separately Excited DC Motor Drives describes about the design and harmonic analysis of Single Phase PWM rectifier with DC motor drives to reduce the current harmonics of the PWM rectifier. A PWM switching technique reduces the harmonics. Comparison of single phase PWM rectifier and single phase controlled rectifier is presented with the use of MATLAB simulation and the programming is accomplished in FPGA to generate gating signals. 

PWM rectifier is power converter to convert an ac to dc that is implemented with power electronic semiconductor switches like MOSFET and IGBT. PWM rectifiers have bidirectional power flows used in battery charger, UPS system, regulated dc voltage source. 

SCR converters have low power factor that result in higher order harmonics. Because of the advent of fast semiconductor devices like MOSFET, IGBT, and pulse width modulation techniques, passive filters are replaced with PWM rectifiers.

The conversion of electric energy is done by semiconducting converters that led to the growth of negative phenomenon to be negligible. Therefore the development of semiconductor structures enabled transmission of higher power to have wide spread of converters.

The block diagram of consists of Power circuit, Load, FPGA controller, Optocoupler, and Driver circuit. A single phase AC supply is fed to the power circuit; the power circuit converts AC/DC where AC supply is converted to DC. Power semiconductor is triggered by the gating signals in the power circuit.

There are two kinds of MOSFETs.  They are Depletion type MOSFET and Enhancement type MOSFET. The converter switches are turned ON and OFF during a half cycle in a PWM control.

Conclusion:

The PWM is used to control rectifiers to eliminate the problems occurred by using phase controlled rectifiers. Hence the PWM rectifiers performs well in many applications like battery charger, UPS system, regulated DC voltage source. The PWM rectifier asserts with its good behavior in many applications and thyristor rectifiers controls load supply grid with consume reactive power and higher harmonics.

Download Harmonic Analysis of Separately Excited DC Motor Drives Electrical and Electronics Engineering EEE Final Year Project Report.

The objectives of this Fabrication of an Automatic Battery Charger Using SCR are an automatic battery charger with and without using trickle charging arrangement. The battery charger controls the charging current with the comparison of the terminal voltage of the battery under charge and constant reference voltage obtained across a Zener diode.

When charged condition of the battery is full then the SCR automatically turns OFF and cuts the battery out of the charging circuit. It keeps the battery healthy by avoiding its overcharging.

A transformer is a static device that has two or more stationary circuits which are interlinked with a common magnetic circuit for transferring electrical energy between them and EMF equation of a transformer is given by e=4.44Baft.

A step up transformer has secondary voltage which is greater than its primary voltage. A transformer is made up of two or more coils of insulated wires wound around iron core. If voltage is applied to one coil then it magnetizes the iron core.

Three phase transformer needs less space than single phase. Three phase is lighter, smaller, cheaper and more efficient and are positioned at 120 degree to each other.

A diode is an electronic component with two terminals to conduct electric current in only one direction and a crystalline piece of semiconductor material is connected to two electrical terminals. The unidirectional behavior is called rectification.

A Zener diode permits current in the forward direction and in the reverse direction when the voltage is larger than the breakdown which is called “Zener knee voltage” or “Zener voltage” which can be measured using Zener diode tester.

A silicon-controlled rectifier is a four-layer solid state device which controls current. SCR has four layers of alternating P and N type semiconductor materials and silicon is used as the intrinsic semiconductor and proper dopants are added to it.

Conclusion:

In this project, Automatic Battery Charger Using SCR  as an Electronic THYRISTOR is used to control the charging system. It is an automatic system with which charging a battery up to 12 volts rating is very easy.

Download Fabrication of an Automatic Battery Charger Using SCR Electrical and Electronics Engineering EEE Final Year Project Report.

The objective of this Digital Phase Selector Electrical and Electronics Engineering EEE Final Year Project Report, the demand is increasing day by day and able to generate power to the requirement, to transmit power with maximum efficiency and minimum losses. The major problem now a day a consumer is facing is power interruption with which major damage is caused to money and sometimes to life and lot of time is wasted. Another major problem with power interruption is in distribution system.

Power instability backs up the utility supply for automation of phase selection or alternative sources of power. Most applications of industrial and commercial are power supply dependent. A digital phase selector is installed in residential and office premises with the use of single-phase equipment. If any mains phase lines go fail then it chooses the available phase line automatically.

All domestic loads are connected to single phase supply and when the fault occurs then power is available in other phases and so we cannot utilize that power. High frequency switching technology is the latest technique that uses infrared radiation for switching purpose and IC MCT2E opto coupler is used. The advantage with this technique is mechanical switching is reliable for single phase supply.

The digital phase selector is able to take power from inverter and when the power fails in all the three phases then availability of inverter gets more reliable. The inverter is charged during normal conditions and gives back up during fault conditions.

The block diagram of digital phase selector has four blocks they are Phase sensing and switching block, Control logic block, Relay driver section, and Power supply unit.

Conclusion:

Electrical energy is the only form of energy available easily and advantage of this energy form is to convert one form of energy into electrical energy and vice-versa and its usage has been increasing day by day. The digital phase selector is an advanced technique used for automation and power quality improvement.

Download Digital Phase Selector EEE Student Project.

Design of Turbo-Alternator Using C-Language: An alternator is an electromechanical device to convert mechanical energy to alternating current electrical energy and any AC electrical generator is called an alternator. Large alternators driven by steam turbines generally are called turbo-alternators.

The types of turbo alternator is based on it construction. They are salient or projecting pole type and non salient or cylindrical pole type. These are high speed machines and are driven by steam turbines and gas turbines with maximum speed of 3000 rpm and can generate up to 1000 MW.

Main parts of turbo alternator are Stator, which is the stationary part of the alternator that carries the armature winding and rotor is the rotating part of the alternator that carries the field winding.

From the block diagram of turbo alternator in the PowerPoint presentation, there is a rotating magnet which is called the rotor and it turns within a stationary conductor that is wound in coils which is called the stator. The field generates an induced EMF (electromotive force) makes the rotor to turn.

The rotating magnetic field induces an AC voltage in the stator windings. Often there are three sets of stator windings, physically offset so that the rotating magnetic field produces a three phase current, displaced by one-third of a period with respect to each other.

The software used to develop the alternator is a C language. It is the most popular and versatile computer language since it is a high level, structured, and machine independent language and the programs written in C have are fast and efficient. C extends its ability and Turbo-Alternator is designed by using C-language.

Conclusion:

Alternator is the main source of electrical energy which we consume. It is the largest energy converter present in the world. This project is about to design a Turbo-Alternator with the help of C-language.

Download Design of Turbo-Alternator Using C-Language.

Complete Self protection Technology to Minimize the Failures of Distribution Transformer: The failure of secondary distribution transformer in power systems described as one of the tragedies of distribution system management in countries like India. With the advent of CSP technology, there is a progressive high performance distribution transforms that mitigate the operation and maintenance problems related with conventional transformers.

CSP technology helps a transformer to protect from faults CSP system. The components are primary fuse used as internal expulsion fuse for system protection and secondary circuit breaker used for overload and secondary fault protection, signal light, the emergency control magnetic trip and surge arrester used for lightning protection.

CSP technology helps the transformer in thermal protection and other important function of CSP technology is use of CSP circuit breaker for secondary fault protection. Therefore the construction consists of circuit breaker along with temperature sensing, latching, tripping and current interrupter.

The coordination between the primary fuse and secondary circuit breaker to perform the task is an important task done by the CSP transformer. CSP technology is low installed cost and requires less time for installation, safe operation and more reliable service.

Transformer is an apparatus of static piece which helps in transforming power from one circuit to another without the change in frequency. It raises or lowers the voltage as current decreases or increases. Transformers have two conducting coils that are linked by a common magnetic flux by a path of low reluctance. The coil that receives power is called primary winding and the coil that delivers the power is called secondary winding and both these coils are wound on a laminated magnetic core material.

The transformer is used depending upon the requirement. Transformer efficiency and performance is unaltered.

Conclusion:

CSP technology has a high performance distribution transformer and better distribution system management. It enables a transformer to protect itself from failures. The transformer protects from over loads.

Download Complete Self protection Technology to Minimize the Failures of Distribution Transformer Electrical and Electronics Engineering EEE Final Year Project Report.

This An Ultrahigh-Speed Low Power Electrical Drive System represents a new ultrahigh-speed drive system capable of operating at 500000 r/min with a power output of 100W for a portable power gas turbine unit and air-compressor application. The spindle drives use induction motors but a number are replaced by PM machines because of higher efficiency and power density.

The applications in the field of portable power generation, small turbo compressors, and spindles need to develop ultrahigh-speed and low power electrical drives. A magnet machine with a slotless litz-wire winding is used that results in a low motor inductance and a high fundamental machine frequency.

A voltage source inverter results in the lowest volume of the complete drive system because of lower switching losses, no heat sink cooling required, a small number of semiconductor devices, and simple control implementation in a low cost digital signal processor.

It is applied in air-compressors, spindle drives and drills and miniature portable power generation systems. When speed of the electrical machine decreases, it has significant advantages for portable power generation. The high-speed electrical machines depend on the power level and the rated speed of the machine.

Emerging application fields for air compressors, ultrasmall drills and spindles, and portable power generation are produced by mesoscale gas-turbines and these applications require a low power and ultrahigh-speed electrical drive system. The application is used for a portable power unit where the output is utilized to power portable electronic devices of up to 100W. The output voltage is dc with a voltage range from 28 to 42 V which is utilized in aircraft and automotive electrical systems.

Conclusion:

The new emerging applications require the developed ultrahigh-speed and low power electrical drives. A 500 000-r/min and 100-W electrical drive system are developed. The PM is inserted inside a titanium sleeve to achieve a small diameter rotor. The entire drive system is extended to higher speeds or power levels with improved bearing technology.

Download An Ultrahigh-Speed Low Power Electrical Drive System Electrical and Electronics Engineering EEE Final Year Project Report.

This A Vehicle To Vehicle Communication Protocol for Co-Operative Collision Warning proposes a vehicle-to-vehicle communication protocol for collision warning. Emerging wireless technologies for vehicle-to-vehicle (V2V) communications promises to reduce the various fatal roadway accidents by giving warnings.

This technology demonstrates that protocol achieves low latency emergency warnings in road scenarios. Zigbee technology is a wireless data communication provided between two vehicles designed around low-power batteries for lasting forever. The measurement of distance is provided by Ultrasonic sensors that transmit and receive ultrasonic signals.

Vehicles are designed to have a smooth means of transportation based on the principles of reliability and safety however, because of reasons like human-error, circumstantial error and negligence accidents happen and many attention is taken by the technologies to reduce traffic accidents. V2V technologies are very simple to implement due to wireless communication.

Zigbee communicates the information between two vehicles and distance measurement between these vehicles is made by Ultrasonic sensor. The microcontroller controls the complete process that sends a signal to buzzer and zigbee after the distance range is obtained. The main aim of this project is to alert the driver as he a vehicle comes to his front.

ZigBee is the high level communication protocols that uses small and low-power digital radios based on the IEEE 802.15.4-2006 standard for wireless personal area networks (WPANs) like wireless headphones. It is suitable for low data rate and low power consumption like Bluetooth and Wi-Fi.

Ultrasonic Sensor is also called transducers that send and receive the signal and works on the principle of radar or Sonar. It evaluates attributes of a target by interpreting the echoes from sound waves or radio. They generate high frequency sound waves received by the sensor and sensors calculate the time interval between sending and receiving the signal to evaluate the object distance.

Conclusion:

The major technical challenge in this project is to get low-latency to deliver emergency warnings in road accidents. The application requirement is to design an effective protocol consisting of congestion control policies, service differentiation mechanisms and methods for emergency warning dissemination.

Download A Vehicle To Vehicle Communication Protocol for Co-Operative Collision Warning Electrical and Electronics Engineering EEE Final Year Project Report