Projects:2019s1-187 Maglev Hovercraft

Project 187 - Magnetic levitation hovercraft

The MagLev Hovercraft project is a collaboration between the EE and Mechanical Engineering students

Team Members

Daniel Perilli
Sam Jordan
Shanghai Bao

Supervisors

Dr Wen Soong
Dr Will Robertson

Introduction

Linear induction motors used in some magnetic levitation (maglev) train designs are capable of providing lift and thrust independently. This project aims to create a vehicle capable of traversing over a planar conductive surface rather than being restricted to a track, in some ways similar to a magnetic hovercraft. Potentially, aerodynamic assistance may be used to supplement lift. The challenges include efficient electrical design of the electric machine and the drive electronics, weight minimisation, heat management and control laws.It is proposed that a team of students from the School of Electrical Engineering will work with a team of students from the School of Mechanical Engineering.The electrical engineering students will be involved with the analysis, simulation and construction of the electric machine and the drive electronics. The work will involve electric machine design and analysis, and power electronics circuit design, analysis, simulation and implementation.

Motivation

Magnetic levitation was first patented as an alternative to wheel-on-rail transport systems in 1912. The advantage of maglev transportation is the removal of friction which is seen between the wheel and road. This makes Maglev more efficient and reduces ongoing maintenance cost compared to other means of transport which are presently much more ubiquitous. As the world seeks more sustainable sources of energy and transportation the increased efficiency that magnetic levitation trains offer compared to conventional wheel on rail transport will continue to drive research into the sector.

There are currently several operational maglev train lines worldwide located in countries such as South Korea, China and Japan. Although these train lines are all completely operational they are all restricted to one direction of travel. If maglev was able to be utilised in all directions like that of a car it would create more possible uses and applications for the system.

Aims

• Understand the principles of magnetic levitation
• Design and create levitating coils linear induction motor
• Levitate single air coils
• Levitate linear induction motor
• Supplement with aerodynamic lift force

Single Coil

We have levitated a single air coil consisting of 125 turns using copper wire of 0.8mm diameter. Largest force that was seen from this coil on an alumni conductive surface was 120 grams of lift. To achieve this levitation we passed through an AC current of 2.5 Amperes at 30V. These conditions enabled the coil to levitate at a height of 10mm.

Inverter

In order to be able to power the single coil with an AC input a single phase H-bridge inverter has been designed. This inverter has been built using a micro controller which powers a signal generator which drives four MOSFETs.

Linear Induction Motor

A linear induction motor (LIM) has been designed using the software package ANSYS Maxwell. The optimisation which was completed in this program produced a LIM which was built using silicon steel laminations (36 laminations). The core consisted of 12 teeth which had 10 copper wires of 0.425mm in diameter all in parallel which were wound 40 times around the core. Before the coils were wound around the core the core was insulated with a varnish which stuck the laminations together as well as provided additional resistance for the core.

The LIM was setup in a testing track and had three-phase power passed through the coils in a four-pole star configuration to maximise the thrust force. Having the LIM held above a testing track which was built by the mechanical engineering team the LIM was able to produce sufficient thrust force to spin the track

File:Linear induction motor.jpg

File:Test track.jpg

Future Work

The initial goals of the project were to have an untethered levitating hovercraft with bi-directional movement capabilities. In order for this to be realised future work on the project would need to be put into constructing the LIM to a more precise specification. The following things will need to be completed to enable this to happen:

• PCB design for three-phase inverter
• Battery sourcing and calculations
• Thermal solutions for the system to prevent overheating and enable desired operation
• Test track needs to be able to measure force of LIM (levitation and thrust) in order to be able to optimise the design
• Additional LIM needs to be built with this the electronics and the batteries being housed in the aerodynamic shell of the hovercraft