Project - Analysis of a practical automotive wiring circuit

1)

• Breakers
• Distributor
• Generator
• Motor
• Battery
• Current and Voltage regulator
• Foot selector switch
• Ammeter
• Fuel guage
• Ignition switch
• Ignition coil
• Starter
• Fuse.

2) Breakers; The breakers action needed when electric current flows along an undesired path with no or less load. If there is no breaker in the circuit, It takes up very high current from the battery and also it damages the battery. It could cause the fire hazards. In the AC systems the phase and neutral touches each other then it cause fire hazards. So breakers can used to avoid fire hazards. In the automotive systems contactors and relays are used as breakers. The relays are identifies the problem or fault related with automotive circuits. The relays provides commands to the contactors. The contactors opens and closes the circuit as per the command received from the relay.

• Breakers are responds rapidly than fuses.
• Breakers are more reliable.
• Breakers are more sensytive.
• These are more compact and have longer life.
• There is no noise is produced during operation.
• It shows high dielectric strength.

Motor; It converts electrical energy to mechanical energy. It can provides power up to Mega-Watt ranges. The main parts of electric motor are Armature, Field, Brushes and commutators. Armature generates torque and Fields generate the magnetic field. The commutator and brushes are used to change the direction of electric current. The working principle of motor is, When a current carrying conductor is placed in a magnetic field , some torque is experienced on the conductor. Brushless direct curent motor and electronically commutated DC motor are used in 2- wheeler- 3 - wheeler electric vehicle. For high power vehicles, permanent magnet synchronous motor, 3-phase induction motor and switched reluctance motor are used.

• Used for high torque applications.
• High power density.
• Portability.
• Speed control is easy and smooth.
• Compact structure.
• Motor has comparatively longer life.
• simple installation and maintanance.
• Poer factor is high.
• Startup power and torque are high.

Battery; Battery is a collection of cells used to store energy. The chemical reactions occuring in the cells of a battery result in the flow of electricity in a circuit. The battery supplies DC voltage. Secondary (Rechargeable) batteries are used in automotive systems. Lithium-ion batteries are mainly used in eletric vehicles. These batteries are commercially superior with superior performance and more cost-effective in terms of battery life and maintanance. It shows high energy density and wide temperature range.

• Long cycle life.
• Wide range of temperature operation is possible.
• Low self discharge rate.
• Higher specific energy.
• Higher load capacity.
• Portability.
• No harmful emissions.
• Can be used in indoor and outdoor applications.
• Less maintanance required.

3) The fuse rating is nothing but the maximum value of safe current flow through the fuse wire before it get melts. The total load coming from the battery is 10 A. if the current exceeds 10 A , the fuse wire will melt and stops the supply.

So the fuse rating should be higher than 10 A. So we can go for 12 A or 13A fuse. It also depends on the type of load.

4) Given datas;

Load = 500 W

We have equation for capacity;

Capacity = Load x time ......(1)

Assuming 24 hours of working time.

Then ......(1) becomes;

Capacity = 500 x 24 =12000 Whr

Therefore, Battery capacity (Amp- hour) = Watt-hour/ volt

= 12000/12

= 1000 Ah

Therefore; Battery voltage = 12 V

Battery capacity = 1000 Ah

5) In the above automotive circuit, the current and voltage regulator is parallel with generator. if the components are connected in parallel, the same potential difference is generated at their ends. so thats the way a steady voltage can maintain at the circuit. This parallel connection will divide the current through the components. so each components get proper or optimum current depending on its resistance.

6) In the above automotive circuit, the battery and Stator are in series. if the components are connected in series, the same current will flowing through both the components. so thats the way a steady current can maintain at the circuit. So this connection will not overheat easily. The series circuit can easily design and understand. This series circuit can provide higher output voltage under adding more power to the system.