# Electrical Engineering Projects | Electrical Engineering Project Ideas

Engineers are always in search of projects, and finding meaningful projects makes that search worthwhile. Listed below are some electrical engineering project ideas for such engineers. A lot of them may deal in higher power than electronics engineers are used to, hence safety first. These hand-picked electrical engineering projects are simple as well as interesting. This is part of the top Electrical projects article.

## Electrical Engineering Projects: Amplifiers

### 4-channel multi-mode audio amplifier

Sometimes we need configurable multichannel amplifiers for experiments or for use in offices or schools. Here is a project based on TDA1554Q, configured for multi-mode functions with four-channel outputs. It has four channels and each channel can provide around 11W over a load of 2 ohms and around 6W over a load of 4 ohms.

The circuit will also work with loads of 4 ohms to 16 ohms. The gain of each channel is fixed at 20dB in single-channel mode and 26dB in BTL mode.

This project is available at: 4 channel multi-mode audio amplifier

### Design and analysis of single-stage amplifier using C++

Many formulae are required to calculate the parameters involved in a circuit of a transistor based audio amplifier. Some of these values involve resistors, coupling capacitor, bypass capacitor, power consumption, current flowing through different components. A good amount of time is required to calculate such parameters even with a regular calculator. Using C++ program, all the parameters can be calculated in a fraction of a second.

This project presents a single-stage transistor audio amplifier that requires a total of 19 formulae to obtain the values of components and analyse the circuit.

This project is available at: Design and Analysis of Single stage Amplifier using C++

### Four-channel video and audio sequencer

This next project is a simple circuit for switching your CCTV camera outputs sequentially. It switches four video and audio channels sequentially, one at a time. It is built around a 555 timer few other components.

The timer is configured as an astable multi-vibrator. A single-side PCB of the four-channel video and audio sequencer is provided along with the component layout. After assembling the circuit on the PCB, enclose it in a suitable plastic box.

This project is available at: Four channel video and audio Sequencer

### High-Impedance audio buffer with JFET

The buffer circuit described here is useful in enhancing the AC input impedance of audio amplifiers used with pickups in musical instruments. Signal sources for amplifiers and passive pickups for electric guitars require very high-impedance of over 5-mega-ohm.

This can be achieved easily with junction field effect transistor (JFET) but may require special design of the printed circuit board (PCB), appropriate construction techniques of the box, proper cables and connectors.

This project provides a solution for a high-impedance, low-cost, low-quiescent current, buffer-follower based on PN4393 JFET.

This project is available at: High-Impedance Audio Buffer With JFET

## Electrical Engineering Projects: Power Systems

### Plus-minus 5V supply from 9V battery

Op-amps require dual-polarity supply for proper operation. When working with battery supply, it becomes difficult to get dual power supply for the op-amps. Presented here is a simple circuit that provides ±5V from a 9V battery. This is one of the interesting projects among Electrical Engineering Project Ideas.

Op-amps require dual-polarity supply for proper operation. When working with battery supply, it becomes difficult to get dual power supply for the op-amps.

This project is available at: Plus-minus 5V Supply From 9V Battery

### 1kW sine wave inverter

An inverter provides power backup for mains-based appliances in the event of a power failure. Most of the inverters available in the market have complicated circuit design and are not very economical. Some of them produce a square-wave output, which is undesirable for inductive loads.

This project presents a simple inverter circuit that produces 50Hz quasi sine-wave output using a single IC CD4047 and some discrete components making it a very cost-effective solution.

This project is available at: 1kW sine wave Inverter

### 4 frequency generators

There is a need for TTL and CMOS signals by stable frequency sources for development, testing and maintenance of digital and analogue electronic circuits. These sources are also useful for fast checking of oscilloscopes, probes, multi-meters, frequency metres and other measurement equipment.

This project proposes a circuit that produces fixed frequencies of 4MHz, 6MHz, 10MHz and adjustable square-wave with variable frequencies from around 10Hz to more than 100kHz.

This project is available at: 4 Frequency Generator

## Sensors in Electrical Engineering Projects

### Dual axis solar tracker system

This system requires the involvement of a wide range of engineering including mechanical electrical and electronics. The mechanical part would involve designing a smooth gear system to move as per requirement. The electrical part would be the working of solar panel and battery requirement. The electronics would involve designing the sensor system that would generate commands for the gear system to act accordingly.

The system employs spur gear for the implementation of the dual axis solar tracker. The system is implemented using Atmel IC AT89C51.

This project is available at: Dual Axis solar tracker system

### PIN diode based fire sensor

This is an ultra-sensitive fire sensor that activates an alarm when it detects fire. In this circuit, a sensitive PIN diode is used as a fire sensor for longer-range fire detection. It detects visible light and infrared (IR) in the range of 430 nm – 1100 nm.

Visible light and IR from the fire activate the sensor to trigger the alarm. It also detects sparks in the mains wiring and if these persist, it gives a warning alarm.

The anode can easily be identified from the top-view flat surface of the photodiode. A small solder point to which a thin wire is connected is the anode and the other one is the cathode terminal.

This project is available at: PIN Diode Based Fire Sensor

### Infrared motion-sensing relay switch

This project is designed for use with all kinds of medium-power automobile/domestic 12V DC loads. It is a simple solid-state relay (SSR) switch, controlled by a standard passive infrared (PIR) motion sensor module. A PIR sensor is an electronic device that can measure IR light radiating from objects in its field-of-view.

Apparent motion is detected when an IR source with one temperature (such as a human being) passes in front of an IR source with another temperature (such as a wall). The PIR sensor module, centred on a PIR sensor, has elements made of crystalline material that generates an electric charge when exposed to IR radiation.

This project is available at: Infrared Motion-Sensing Relay Switch

### Low-cost LPG leakage detector

The circuit for an LPG leakage detector is readily available in the market, but it is extremely expensive and usually based on a microcontroller (MCU). This project presents a low-cost circuit for an LPG detector that you can build easily. The main objective of the circuit is to detect LPG leakage anywhere.

At the heart of the circuit is dual comparator IC LM393 (IC2). It is used to compare two different voltages, in this case reference voltage and MQ-6 gas sensor output voltage.

This project is available at: Low-Cost LPG Leakage Detector

### Low-cost dusk-dawn controller

This dusk-dawn controller is built around a light-dependent resistor among other components. The common battery supply is used for operating the circuit as well as for load, that is, for power LED/small inverter circuit.

Resistors work as voltage divider and current limiter in the circuit. LEDs are used as circuit deactivation indicator. An n-channel MOSFET is used for the switching action of an LED light.

This project is available at: Low-Cost Dusk-Dawn Controller

### Vibration activated smart CRO probe

This is a simple, low-cost, energy-saving and device-saving circuit for an electronics lab, service centre, electronics workshop, or wherever a CRO is in use. Generally, in a repair station, a CRO is used for a very short time. But in most cases, the user fails to switch off the CRO immediately after use.

The service engineer mostly concentrates on faults rather than noticing whether the CRO is on or off. A vibration sensor turns the CRO off when the probe is idle for a specified amount of time.

This project is available at: Vibration Activated smart CRO probe

## Electrical engineering projects: LED systems

### Automatic anchor light

Federal and international regulations require boats to carry lights during sunset, sunrise and at conditions with restricted visibility. The number and colors of light vary with the size of vessel. A masthead anchor light is out of fashion as it is too high above the water level.

This makes it difficult to judge the position of the boat, especially in a pitch-dark anchorage.

This project is a compact yet inexpensive automatic anchor light integrated with an ambient light sensor that turns it on and off automatically.

This project is available at: Automatic Anchor light

### High power LED stroboscope

Stroboscope is a convenient and accurate enough instrument to measure speeds of rotating objects in homes or industries. One can use it to find the speed of fans, motors or any other rotating object. It is a flashing light that provides sharp light pulses at a variable rate. An object rotating with frequency matching the pulsed light is observed as stationary.

This project is available at: High Power LED Stroboscope

## Miscellaneous electrical engineering projects

### Configurable RS232 to TTL to I2C adapter

RS232 signals cover a much longer distance than standard TTL and I2C signals. These signals have better noise immunity as well. RS232 is a well-known standard supported by many popular ICs and therefore is still widely used. Sometimes we want to send TTL and I2C signals over a longer distance. This project describes how these signals can be extended through RS232 lines.

This project is available at: Configurable RS232 to TTL to I2C adapter

### Automated USB controlled power switch

Power for TV and set top box (STB) is derived from a common switchboard. The switched-mode power supply (SMPS) of the TV continues to draw a small amount of power from mains and the STB is not switched off when you switch off the remote.

This next project presents a circuit that can control mains power of an LED TV and the DTH STB. It also protects the devices from harmful initial surges when power comes back after a power failure.

This project is available at: Automated USB controlled Power Switch

### Programmable 3 phase controller for ON/OFF motor

A programmable time switch is useful in designing an automatic on/off controller for 3 phase electric motor. This next project proposes a system with two programmable time switches for setting the starting and stopping times of the motor.

Two control circuits interface with the start/stop switches of the 3-phase motor starter. There is provision for setting days of the week for the controller to function as well.

This project is available at: Programmable 3 phase Controller for ON/OFF motor