Switch magnetic field device study

Abstract

The purpose of this project is to design and fabricate a switch magnetic field device using neodymium iron boron magnet to concentrate the magnetic field using power electronics with the eventual aim of determining if the device can be used in a diaphragm pump.

Diaphragm pumps are hydraulically or mechanically actuated positive displacement pumps designed to handle a variety of pressures and flow rates. They are pumps that use the up-and-down movement of a cupped, elastic surface to generate liquid flow. When the pump pushes into the liquid, it adds pressure and displaces a certain amount of fluid. When it is pulled back from the liquid, it draws in more fluid. The diaphragm pump uses check-valves to prevent the backflow of fluid through the entry valve. Diaphragm pumps incorporate either hydraulic fluid or pistons to control the movement of the diaphragm. [1]

The eventual aim of this project is to replace the hydraulic or mechanical actuator in the pump with an actuator that is driven by magnetism instead. This is to be achieved using the switching of magnetic fields to move the actuator. The main factor that determines if this idea can be implemented successfully will be the force that can be produced from the device.

In order to generate the switching field effect, power electronics specifically a H-bridge is needed to produce the effect. Finding a suitable H-bridge is essential to the successful operation of the circuit.

Finally, a comparison of the magnetic force produced from the different designs will be done and suggestions for future design improvement that hopefully leads to the successful implementation in real life.