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santoshchikkur
santoshchikkur

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Electric and Hybrid Vehicle technology PART-2

Hello Readers,
My name is Santosha S Chikkur, and I work at Luxoft India as a Junior Software Developer. Luxoft has given me several opportunities to work on various projects, which has inspired me to learn the essential processes involved in developing AUTOSAR Modulеs and Add-Ons "Electric and Hybrid Vehicle technology PART-2."

ELECTRIC VEHICLE COMPONENTS

  1. Motor
  2. Controller
  3. Charger
  4. Dc/Dc Converter
  5. Battery Management System
  6. Instrumentation
  7. Contactor(s)
  8. Safety Equipment

Motors

Electric motors are the main source of power, for an Electric vehicle, which converts Electrical Energy into Mechanical Energy. There are mainly 2 types of Electric Motors used in EVs: DC Motors and AC Motors. The main components of DC motors are.

  1. A set of field coils around the border of the engine that makes an attractive drive that gives torque.
  2. A rotor or armature installed on the bearing.
  3. A commutating device, which reverses the magnetic field and makes the armature turn.

AC Motors are similar to DC motors, but they don’t need any Commutating devices, since there is a continuous current reversal. Both AC and DC Motors have their advantages and disadvantages, so they are not superior to one another.

Electric Motor Comparison

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AC Motor
1) Fail-safe design, Low initial torque, higher speed
2) Requires complicated electronics package
• AC speed control (similar to industrial)
• Inverter (convert DC to AC)
• High voltage (240-350 V)
• Bearings are the only mechanical maintenance item

DC series wound
1) Motors are available and inexpensive
2) 100% torque at 0 RPM
3) Controllers are very cheap compared to AC
4) No inverter stage is required
5) Lower voltage system (72-156 VDC)
6) Bearings and brushes are potential maintenance items.

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A: shunt
B: series
C: compound
f= field coil

Controller

An engine controller could be a gadget or bunch of gadgets that serves to oversee in a few foreordained ways the execution of an electric engine. An engine controller might incorporate a manual or programmed implies for

  • Starting and stopping the motor
  • Selecting forward or reverse rotation
  • Selecting and regulating the speed,
  • Regulating or limiting the torque
  • Protecting against overloads and faults

Battery management system
There are three fundamental targets common to all Battery Administration Frameworks

• Secure the cells or the battery from harm
• Prolong the life of the battery
• Keep up the battery in a state in which it can fulfill the useful prerequisites of the application for which it was indicated.

Most electric vehicles use lithium-ion batteries. Lithium-ion batteries have higher vitality thickness, longer life span, and higher control thickness than most other viable batteries. Complicating variables incorporate security, solidness, warm breakdown, and fetched. Li-ion batteries ought to be utilized inside secure temperature and voltage ranges in arrange to function securely and effectively. Increasing the battery's lifespan decreases effective costs.
One strategy is to function a subset of the battery cells at a time and exchanging these subsets.

DC/DC convertor

An electric car still uses a 12-volt system to power all of the original 12-volt accessories: Lights, horn, etc.
This may too control a few control circuits for the electric drive framework. However, unlike a gas car, there is no alternator to keep this battery charged. One choice within the early days of EVs was to utilize a profound cycle 12-volt battery, as overwhelming obligation as possible, and energize it after you charge the most battery pack. Usually not satisfactory in case any sum of night driving is aiming.

The solution is a DC/DC convertor. This taps the complete battery pack voltage and cuts it down to a directed yield, comparative to that from an alternator. By tapping the total pack, there's no uneven release. Amperage required is so moo that there's a small impact on the extend. Isolation of the high and low-voltage systems is maintained inside the DC/DC converter. This also eliminates the need for a separate 12-volt charging circuit for an auxiliary battery.

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Contactor

A contactor is an electronic switch that can handle high power. It includes a coil that is powered by a low voltage, often 12V in electric vehicles. When the coil is activated, it closes the contacts, enabling electricity to pass through. In electric vehicles, contactors are employed to disconnect the battery pack once the key is switched off, similar to turning off the ignition in a traditional vehicle. For most electric vehicles, contactors with a continuous rating of around 200 amps are suggested, while higher-performance electric vehicles may require contactors that can handle up to 600 amps continuously.

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Pot box

Petrol vehicles use a cable that links the accelerator pedal to the engine's throttle. In EVs, this setup is replaced with a connection to a pot box, essentially an electronic throttle connected to the motor speed controller. Most pot boxes are simply an industrial variable resistor (5Kohm is the standard) in robust packaging. Newer motor speed controllers are utilizing digital pot boxes with optical encoders, resulting in increased reliability.

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Instrumentation

The main two gauges you will need to add for an EV are a voltmeter to monitor your battery pack voltage and an ammeter which measures the current coming Some electric vehicles feature a "state of charge" meter in addition to a fuel gauge. This meter employs advanced electronics to determine the power usage from the battery and estimate the remaining battery capacity based on that information. capacity you have left. Some vehicles can function as a trip computer, informing you about your remaining range. Those with a reliable battery management system might feature a screen displaying the voltage levels of all batteries in the pack. This provides a useful method for monitoring the condition of individual cells and preventing any from becoming excessively discharged.

This will be continued in the next article, including examples. Please let me know in the comments below if you have any questions. Thanks for reading.

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