Progress Presentation

Today, we presented to our lecturers all our work to date. The reasoning behind our presentation is to help keep us on target. It was a wake up call as it was my worst presentation that I have ever participated in. Not only was I late, I was also ill prepared. I felt like a robot without a brain and when it came time for the lecturers to provide their feedback, lets just say we had a lot of constructive criticism. 

If we are to move on from today, we need to pick up the pace, put our heads together and get the work done. I hope to meet with Azizi in the holidays to complete the majority of the practical work done so that we may begin with our written report.

Circuit Operation

During normal vehicle operation, the suspension oscillations will cause the generator to jounce up and down in a vertical motion with the vehicles unsprung mass due to the generator being fixed to the vehicles chassis. This causes the rotor to simultaneously pulsate in and out of the coil windings, thus cutting through the lines of magnetic flux and inducing a current and AC voltage in the copper wire (stator). 

From the stator, current conventionally flows to the bridge rectifier, where the AC voltage is converted to workable DC voltage. The output voltage then flows to the capacitor and begins to charge it. Once the peak charge threshold is met then the current is redirected to charge the battery.

The Generator Componentry

The generator consists of two major components, the rotor and the stator. The rotor is the oscillating moving part while the stator is the static section. The rotor and the stator are separated by a small air gap to allow the oscillating movement between the rotor and stator to take place.

Figure - 1: Generator componentry

The permanent magnet is fixed to the linkage rod and acts as a rotor. Meanwhile the coil windings and the steel plate play the role of a stator. In order to make the magnetic circuit as efficient as possible, the magnetic field passing through the coil must be maximized. To allow for this the coil windings were selected from a  material type with a low permeability.

Figure - 2: The generator schematic diagram

At the heart of the generator is the accumulator, which filters the generated output voltage through a rectifier and  a capacitor. The battery would be connected in parallel with the capacitor.

The Generator Circuit

Figure - 1: Generator charging circuit wiring diagram

Figure - 2: Generator schematic

Charging Circuit Requirements

A charging system must meet the following criteria while the engine is still running:

- Supply the current demands made up by all loads

- Supply whatever charge current the battery demands

- Operate at idle speed

- Supply constant voltage under all conditions

- Have an efficient power to weight ratio

- Be reliable, quiet, and have resistance to contamination

- Require low maintenance

- Provide an indication of correct operation

Researching Charging Circuits

A charging system performs several functions. These include:

1. It recharges the battery after engine cranking or after the use of electrical accessories with the engine turned off.

2. It supplies all of the vehicles electricity when the engine is running.

3. It must alter its output to meet varying electrical loads.

4. It provides a voltage output slightly higher than battery voltage.

Components:

1. Generator- Utilizes kinetic energy to generate electricity.

2. Voltage regulator- An electrical device which is used to control the current and output voltage of a generator.

3. Charge Indicator- A warning lamp, ammeter or voltmeter to inform the driver of the charging system condition.

4. Wiring Harness- Charging system wiring that connects system components.

5. Battery- Provides current

Final Contract Signed

We met with our lecturers today to present our final contract for approval. We have been working towards this moment for quite sometime now, and we began to realise that any rejection would be a step backwards for us. It would also mean that we would fall behind schedule, which would make it a more difficult task for us to meet our deadlines. 

Luckily, we were met with positive feedback and our project contract was finally approved. This meant that we were now able to progress to the next stages of our project and begin the time consuming task of in-depth research of our topic.