Development of a cascaded control scheme for asymmetrical half bridge multilevel inverter

Our project introduces the new topology based on conventional asymmetric cascaded H-bridge inverter. The problem addressed in the existing topologies is the requirement of large number of switches. The project introduces an alternative solution for the reduction of switches by the elimination o

Project Title

Development of a cascaded control scheme for asymmetrical half bridge multilevel inverter

Project Area of Specialization

Shared Economy

Project Summary

Our project introduces the new topology based on conventional asymmetric cascaded H-bridge inverter. The problem addressed in the existing topologies is the requirement of large number of switches. The project introduces an alternative solution for the reduction of switches by the elimination of polarity changer with the reverse polarity DC source. Thus, this eliminates the need of four switches by replacing polarity changer with one reverse polarity DC source without affecting the flexibility and simplicity of the cascaded H-bridge inverter. Consequently, reducing the overall cost and size for multilevel inverter. The technique used in the project is the addition of half bridge cell with the reverse polarity DC source equal to the summation of all other DC sources. Closed loop with PWM (PI controller) is implemented to control the output voltage to desired value.

This project comprises of hardware as well as software model. The hardware model comprises of MOSFET, DC sources, PWM carrier and PI controller. The software implemented in this project is Matlab / Simulink for real-time simulation of the proposed model.

Project Objectives

The main objectives of the project are:

•Development of Cascaded Control Scheme for Asymmetric Cascaded Half-Bridge MLI

•Fabrication of Hardware of Asymmetric Cascaded Half-Bridge MLI

•Performance Analysis of Hardware.

•Validation of Hardware Results with Simulation Results.

Project Implementation Method

Diagram of proposed System:

                                           

Components of proposed topology:

The project consists of 3 DC sources of 12V, 24V and 36V (reverse polarity), 6 MOSFETS with anti-parallel diodes (switches), PWM multicarrier (to generate gate signals), PI controller circuit, RC filter and RL load. 

Software Implementation:

Simulate the proposed topology in Matlab/ Simulink.

Hardware schematics:

Designing of the hardware model of PWM seven carrier which provides the gate signals to the PI controller model. We are using 6 MOSFETs to provide switching. Each H-bridge cell consists of 2 switches and a DC source. DC sources are of 12V, 24V and 36V (reverse polarity). The cell of 36V is connected in reverse polarity, which equals to the summation of the other two sources. Thus, it provides the negative peak output voltage and eliminates the need of polarity changer. The model will be drawn on Arduino board and appropriate housing will be provided.

Benefits of the Project

• This project proposes an arrangement of switches for asymmetric cascaded half bridge multi-level inverter that eliminates the need for polarity generator circuit. Ultimately, reducing the number of switches.
• Reduction in switching losses.
• It is a cost-effective solution that converts DC power to AC power efficiently.
• Reduction in harmonic distortion makes it suitable for application in Interface of Renewable Energy Sources and Flexible AC Transmission Systems (FACTS).
• Overall size and cost is reduced.

Technical Details of Final Deliverable

We shall deliver fully functional hardaware and software model of a cascaded control scheme for asymmetric half bridge multilevel inverter.

Technical details are mentioned as follows: 

Batteries: We are using three batteries of 12V each, to generate 12V, 24V and 36V to power our circuit.

Power MOSFETs: Mosfets are used for highly efficient switching. They are used in our circuit to give us precise steps in output waveform, according to the gating signals provided.

PCB: PCB is used to mechanically suppport and electrically connect all the components of the circuit.

PCB drill: It is required for drilling the PCB.

Breadboard: It is used to model a test circuit in hardware construction, in our project.

Arduino: It is used to incorporate the PI controller in the feedback path of our project.

Soldering iron: It is used to solder all the components to the PCB board.

DSP kit: We require DSP kit to analyze different digital signals.

Current sensor: It is required to sense current in the current feedback loop for asymmetric cascaded hlaf bridge multilevel inverter.

Voltage sensor: It is required to sense voltage in the voltage feedback loop for asymmetric cascaded hlaf bridge multilevel inverter.

Operational Amplifier: Several op amps are used to generate the required gating signals for mosfets.

Load: Different rating bulbs are used as load.

Final Deliverable of the Project

HW/SW integrated system

Type of Industry

Energy

Technologies

Others

Sustainable Development Goals

Responsible Consumption and Production

Required Resources

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