Design and implementation of Inverter for general load
Electricity is the major source of power for country's most of the economic activities. But in Pakistan, we have been suffering for the electricity crisis for a long time. To reduce this problem, there are some alternative ways which can help in this purpose. But among all of the methods solar syste
2025-06-28 16:26:24 - Adil Khan
Design and implementation of Inverter for general load
Project Area of Specialization Electrical/Electronic EngineeringProject SummaryElectricity is the major source of power for country's most of the economic activities. But in Pakistan, we have been suffering for the electricity crisis for a long time. To reduce this problem, there are some alternative ways which can help in this purpose. But among all of the methods solar system may be an easy and effective one especially in the rural areas where the electricity has not reached yet. As Solar cells require an inverter because their DC output needs to be transformed into AC. The main reason for this is that most of our home appliances need electricity in AC form to function correctly. So, the inverter does the conversion job. It receives DC electrical energy from solar cells. Due to lack of proper inverters, the companies provide usage of DC appliances only not AC appliances. The reason is that the existing inverter produces modified sine wave (square sine wave) which causes major power losses and harms to AC appliance. But in comparing to pure sine wave, it has better performance than modified one and the power loss is less. For that reason, our objective is to design a pure sine wave inverter which can be used in the Solar Home System at an affordable cost. In this project, our aim was to design a pure sine wave inverter which is the digital versioned circuit using micro-controller applications. Solar energy has proved to be a very promising alternative because of its availability and pollution-free nature. Due to the increasing efficiencies and decreasing cost of photovoltaic cells and the improvement of the switching technology used for power conversion, we are interested in developing an inverter powered by PV panels and that could supply stand-alone AC loads and also be connected to the grid.
This project mainly focused on the performance analysis of the inverter for the cases of resistive load and inductive load. The waveform of resistive load and inductive load will face whether unity power factor, lagging or leading effect. A proper switching in the inverter are important as to avoid any probability of generating the wrong pattern of waveform which later could impose the appearance of harmonic. The proposed inverter output 1000W (1kW) 220 Volts inverter at a 50Hz of frequency, proved to be better in sinusoidal performance and shape compared with others, where the total harmonic distortion (THD) is less than the standard value of 5%. Also it can be used for applications where the output ac voltage is larger than the input dc voltage. This will provide a better economic and technical advantages.
Project Objectives- Considering the importance of a Inverter, following are the main objectives of our project:
- To design and implementation of economical cost of Inverter producing pure sinusoidal waveform for full households, amenities in homes.
- To improve the existing model of inverter by employing efficient MATLAB/SIMULINK model to enhance power system stability and will have minimum THD.
- To convert the DC power into AC for drive the AC motors.
- To design an inverter circuit with under voltage over voltage protection.
- To provide a noiseless and weightless source of electricity generation
- To provide a source of electricity power with low maintenance cost and zero fuel cost.
The most practical way to achieve the final power goal will be to split the design process into a number of phases. This is largely due to the fact that lower voltages are simpler to work with in regards to efficiency and heat considerations. There are four phases, each described below:
Phase One: The group will model four initial designs using PSPICE. Special attention will be paid to the efficiency of these designs, which is amongst the most important design parameters. The group will buy a commercial inverter (designed for 12 V DC use), reverse engineer the layout, and model? close attention paid to board layout.
Phase Two: The group will analyze the PSPICE models from phase one and select the best with regards to efficiency and practicability. This design will be prototyped and the current will be increased to find the power limits of the material being worked with beginning with silicon transistors. Heat dissipation solutions will begin being formed.
Phase Three: The proposed design from phase one is prototyped using updated materials (Gallium Nitride and/or Silicon Carbide). Power is stepped up to test new materials for their limit. Heat sink solutions are expanded to include the use of aluminum, synthetic diamond, and thermoelectric coolers. Power is stepped up a final time.
Phase Four: The chosen design is built with the use of printed circuit boards, custom enclosure, and heat solutions. 100+ hours of testing is performed at objective specifications while design issues are troubleshooted and solved.
The square wave output is quite far from the waveform available from normal main outlet, and this can cause problems on equipments originally design with the sine wave power in mind. Most devices with variable speed such as electric drills and equipments such as cordless drills and screwdrivers behave irrationally when operating on square wave inverters. The next step that is close to the mains sine wave is called the modified sine wave. This has become popular in many inexpensive inverters because it is quite easy to make with modern electronics. This type of inverters generally uses a Switch mode power supply that generates de voltage. The modified sine wave is compatible with electronics but it may induce long mechanical buzzing. The true sine wave inverters allow connected load equipments to operate in the same way as they would from mains supply. The only problem is that true sine wave inverters are very expensive compared to the modified and square wave inverters.
Finally the success of this study will be beneficial to the society at large. Mass production of inverters will lead to improved standard of living of the populace and the nation will move forward in its pursuit of technological development.
Benefits of the ProjectThis project covers a lots of applications in industrial and commercial sector, but some of the major benefits of this project, based on what this project was chosen to work on are:
- An uninterrupted power supply (UPS) supplies AC power with the help of an inverters and battery combination.
- Speed Control of Electric Motor: An inverter is designed to produce a variable output voltage and by controlling the output voltage of the inverters, we can control the speed of an electric motor.
- Solar: Output of solar PV panels is DC. So, we have to convert it to AC for that inverters are used.
- HVDC transmission line: For bulk power transmission, the HVDC transmission line has more advantages than the HVAC transmission line. In this transmission network, power generated in AC and convert in DC with the help of a rectifier and transmit this DC power for long-distance. The inverters used to convert the power into AC at the receiving end of the transmission line.
- Electroshock weapons:
Electroshock weapons and tasers have a DC/AC inverter to generate several tens of thousands of V AC out of a small 9 V DC battery. First the 9 V DC is converted to 400–2000 V AC with a compact high frequency transformer, which is then rectified and temporarily stored in a high voltage capacitor until a pre-set threshold voltage is reached. When the threshold (set by way of an airgap or TRIAC) is reached, the capacitor dumps its entire load into a pulse transformer which then steps it up to its final output voltage of 20–60 kV. A variant of the principle is also used in electronic flash and bug zappers, though they rely on a capacitor-based voltage multiplier to achieve their high voltage -
Miscellaneous: Typical applications for power inverters include:
- Portable consumer devices that allow the user to connect a battery, or set of batteries, to the device to produce AC power to run various electrical items such as lights, televisions, kitchen appliances, and power tools.
- Use in power generation systems such as electric utility companies or solar generating systems to convert DC power to AC power.
- Use within any larger electronic system where an engineering need exists for deriving an AC source from a DC source.
This section specifies information for the design and specification for fabrication of the inverter components such as Switches, SCRs, Resistors etc
Hbridge using IGBTs: A set of four insulatedgate bipolar transistors configured in Hformation, using pulse width modulation from a TI MSP430 to achieve as highresolution 50 Hz sine wave. This design would require gate drivers on either side of the bridge that would drive either the high side or low side IGBTs. Utilizing gate drivers allows a level of control and isolation between the MSP430 PWM pins and the gates of the IGBTs. The output rails of this bridge would require a RLC resonant filter to filter out the switching artifacts and leave a high resolution sine wave
Quantizedstep MOSFET with output transformer: Metaloxide semiconductor fieldeffect transistors are configured to deliver ¼, ½, ¾, and full voltage of positive and negative peaks, triggered with a TI MSP430 to create a four step sine wave. This sine wave would not have a high resolution but offers respectable efficiency in the creation of the wave. The outputs of the individual MOSFETs creating each piece of the sine wave can only be as large as the supplied DC voltage rail so the resulting stepped output is then increased to the desired line voltage of 120 volts by utilizing an output transformer.
555 bridge design: A 555timer is biased to create a continuous periodic 50 Hz pulse that is used to trigger a pair of NPN and PNP transistors. The transistors are used as valves to control the current direction from the energy stored in a resonant CL (capacitorinductor) circuit tied to the drains of the NPN and PNP transistors. This CL circuit is designed to serve as a sharp resonance filter at 50 Hz. This filter has a very high Q which only allows the 50 Hz harmonic to pass through. This sine wave is then stepped up using an output transformer to the desired output line voltage of 120 volts RMS.
The required 170 volt DC rail comes from a series of DC to DC converters that will step the supplied DC voltage. These converters all must be rated at the final power specification of the inverter because they will be in series with the input supply and output load. This high power throughput makes these parts very hard to find to fit the size constraint of the teams project, so there is a possibility of the group building a switching supply to achieve the desired power and fit within the enclosure.
In order to power the microcontroller used to create the PWM feeding the gate drivers another set of DC to DC converters will be used to drop the supplied voltage down to a usable voltage that will power the microcontroller. This voltage is approximately 5 volts at a very lower current so the size of the needed DC to DC converter is small because of the low power constraints.
Final Deliverable of the Project Hardware SystemCore Industry Energy Other Industries Education , Medical , Agriculture , Food , Manufacturing , Telecommunication Core Technology Clean TechOther Technologies Shared Economy, OthersSustainable Development Goals Good Health and Well-Being for People, Affordable and Clean Energy, Decent Work and Economic Growth, Industry, Innovation and Infrastructure, Responsible Consumption and ProductionRequired Resources| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 61350 | |||
| 120 volt Gate Driver (UCC27211A) | Equipment | 2 | 175 | 350 |
| DCDC Converter (50V 3V) | Equipment | 3 | 2000 | 6000 |
| Silicon Carbide MOSFETs (C2M0025120D) | Equipment | 4 | 10000 | 40000 |
| Heat Sink | Equipment | 1 | 1500 | 1500 |
| Enclosure | Equipment | 1 | 1500 | 1500 |
| Arduino Microcontroller | Equipment | 1 | 900 | 900 |
| Printed Circuit Board (PCB) | Equipment | 1 | 1000 | 1000 |
| 1kVA Transformer | Equipment | 1 | 1800 | 1800 |
| Voltage Relay | Equipment | 1 | 1800 | 1800 |
| Electronic Components(Capacitors, Resistors, Diodes etc) | Equipment | 1 | 1500 | 1500 |
| Printing, Thesis Writing, Poster printing | Miscellaneous | 1 | 5000 | 5000 |