Design and Implementation of Grid tie Multi level inverter Fifteen Levels

Electrical energy generation from renewable energy sources such as sun, wind etc., are widely adopted due to the increase in electricity consumption. The integration of renewable energy sources with the grid plays an important role in energy utilization. It is difficult to utilize electricity from r

Project Title

Design and Implementation of Grid tie Multi level inverter Fifteen Levels

Project Area of Specialization

Electrical/Electronic Engineering

Project Summary

Electrical energy generation from renewable energy sources such as sun, wind etc., are widely adopted due to the increase in electricity consumption. The integration of renewable energy sources with the grid plays an important role in energy utilization. It is difficult to utilize electricity from renewable energy sources directly for the injection of power into the grid. Hence the system needs power electronic converters as an interface between renewable energy sources and grid/load. The most desired of renewablle source is solar panels or UPS. The problem with conventional or most commonly used inverter circuits have problem with its inverter circuits and filters used in it. The performance and cability to drive load reduce with time and due to unclean power, it damages appliances. To overcome this problem, we will implement multi-level inverter to achieve output as close as possible to sinosoidal to reduce filter requirements and give clean power and tie it with grid to get the advantage of selling the generated power. This system can be made cost effectively because this system doesn't need any isolation transformer.

  The devices available now a days in markets is very costly and mostly imported from China and have costed 3 to 4 Lacs per device. Two of these devices are installed in Islamabad by an NGO in their offices but not everyone can afford it. By following the topology we propose, the developed device will cost only Rs.70,000/- (APPROX.) which can be reduced when we manufacture it in more number of units due to decrease in cost of components to be purchased in bulk amount. Due to this low cost and reliability of our device it will turn the tables in inverter market. In addition to this advantage, the user will also be able to sell the surplus amount of Energy generated to WAPDA.

Project Objectives

The main aim of the project is to develop a 15-Level inverter to generate sinusoidal output voltage waveform.

 After implantation we will be able to achieve following objectives.

• Implementation of Grid tie Multi-level inverter.
• Reducing harmonics with more number of levels (15-level) with less number of switches
• Verification of the idea by simulating it in MATLAB/SIMULINK

Hardware implementation of idea to achieve as close as possible sinusoidal waveform.

Project Implementation Method

The proposed project has two phases. In first phase, 15 level inverter will be implemented in MATLAB Simulink and results will be verified. Then, in phase 2, hardware prototype will be developed for already simulated project and practical results will be verified by attaching it to grid.

The 220V AC is stepped down to 3V by using Potential Transformer of appropriate rating. This 3V is used by Arduino to give pulsating output which is used by driver circuit to drive Multi-Level Inverter.

The input DC power will be generated by solar panels which will be fed to 15 level inverter through DC-DC converter which will give the input power in required level. Pulse generator will generate the pulse and fed it to logic circuit PWM generator will modulates the pulses and is given to driver circuit. Logic circuit will amplify the pulses and provide isolations by using opto-coupler. It has two functions,

1. Amplification
2. Isolation 

The Arduino is used to generate the PWM pulses for converter and inverter circuit. The Arduino pulses are given to the driver circuit as input. Driver board is mainly used to isolate and amplify the input signals from the controller. The amplified driver output will be connected to the main power circuit devices. And the devices are turned on by using the PWM pulses. The bridge rectifier converts the ac voltage into dc voltage.

Benefits of the Project

Cheap an Reliable Product

Like many other countries, Pakistan is also changing its strategy in power sector, due to high shortfall and large number of consumers, by procuring the power generated by domestic consumers by renewable energy sources. It is already been initiated by Islamabad Electric Supply Company (IESCO) and is implemented in various localities. But the inverters used are very costly as they are mostly imported from China. Our prototype has a very less cost than those equipment and will be developed using locally manufactured / available components.

Cleaner Output Power 

Modern industrial devices mostly base on electronic devices that are very sensitive to harmonics, even for the induction motor whereby generating extra heat with higher harmonic level. To overcome above-mentioned problems, multilevel inverter is proposed to produce output with minimum distortion.

Distribution Voltage Level as there is a strong demand to push voltage-source inverters (VSIs) into distribution voltage level, which is between 11–16 kV. Currently, the power electronics for distribution and transmission voltage levels are mainly dominated by current source converters, which use thyristor devices with built-in reverse voltage blocking capability. The main problems with thyristors are their sluggish switching speeds and their inability to gate off. With the use of gate-turn-off high-voltage semiconductor devices in multilevel inverters, the widespread use of VSIs in distribution voltage level can be easily expected.

Distributed energy systems, mostly those using alternative energies such as photovoltaic panels and fuel cells, can be easily configured with a separate source connected through the power conversion circuits used as an energy module or building block to provide individual output. A cascaded inverter can then be configured with multiple modules. Such a system does not need a transformer to provide isolation, and the system can be constructed in a cost effective manner.

Technical Details of Final Deliverable

Our Project will have THD analysis of software design and hardware prototype.

Hardware will be capable of generating 12V DC and will convert it to 220V AC with the help of Multi-level inverter with PWM techniques to produce staircase voltage levels closer to sine wave. Remaining harmonics will be removed with the help of LC filter designed of desired rating.
Finally, this voltage will be synchronised with Grid by using zero-cross detection technique. 

Final Deliverable of the Project

Hardware System

Core Industry

Energy

Other Industries

Core Technology

Clean Tech

Other Technologies

Sustainable Development Goals

Affordable and Clean Energy

Required Resources

If you need this project, please contact me on contact@adikhanofficial.com