(SEM IV) THEORY EXAMINATION 2023-24 ELECTRIC AND HYBRID VEHICLES

This document is a B.Tech (Semester IV) Theory Examination Question Paper for a subject related to Automobile Engineering / Electric & Hybrid Vehicles.
It is a 3-hour, 70-mark examination designed to evaluate a student’s understanding of automobile fundamentals, chassis and body structure, electric vehicles, hybrid vehicles, motor drives, controllers, EV charging technologies, and energy storage systems.

The paper is divided into three structured sections—A, B, and C—covering short conceptual questions, descriptive answers, and application-based long-form questions.

SECTION A – Short Answer Questions (14 Marks)

Seven short questions (2 marks each) assessing the foundational concepts of automotive and EV technology:

Definition of automobile                            Differences between body and chassis

Definition of electric vehicles (EVs) and how they differ from internal combustion engine (ICE) vehicles

Definition of hybrid vehicles and their dual-power operation

Types of electric components used in EVs/HEVs (motors, batteries, converters, inverters, etc.)

Role of a controller in EVs and HEVs          Types of EV chargers available (Level 1, Level 2, DC Fast Charger, etc.)

This section tests conceptual clarity and general automotive knowledge.

SECTION B – Descriptive Questions (21 Marks)

Students must attempt any three of the following 7-mark questions:

a. Functions of an Automobile Chassis

Describes structural support, load carrying, engine mounting, suspension, braking, aerodynamics, and safety roles.

b. Types of Hybrid Vehicles

Covers mild hybrid, full hybrid, plug-in hybrid, series hybrid, parallel hybrid, and power-split hybrid.

c. DC Motor Drives vs Other Drives

Explains differences in torque characteristics, control simplicity, acceleration response, and efficiency.

d. Working Principle of a Basic Vehicle Controller

Describes computing unit operations, sensor inputs, CAN communication, power electronics coordination, and motor/battery management.

e. Level 1 EV Charger Working Principle

Explains home-outlet charging, AC supply flow, onboard charger conversion, low charging power, and safety mechanisms.

Section B evaluates the student’s ability to write structured explanations and discuss engineering concepts.

SECTION C – Long Answer / Application-Based Questions (35 Marks Total)

Each question contains two choices; students must attempt one from each number.

3. Automobile Layout / Engine Placement (7 Marks)

Option (a)
Basic layout of a four-wheeler:

Engine                                             Transmission

Differential                                      Propeller shaft

Wheels                                            Suspension

Steering                                           Brakes

Chassis frame                                  Electrical systems

Option (b)
Importance of front-engine and rear-engine layouts (handling, weight distribution, traction, maintenance, and vehicle class suitability).

4. Advantages or Disadvantages of EVs (7 Marks)

Option (a)
Advantages: zero tailpipe emission, quiet operation, low running cost, efficiency, fewer moving parts, regenerative braking.

Option (b)
Disadvantages: high cost, limited range, charging infrastructure issues, long charging time, battery degradation.

5. Motor Drive Technologies (7 Marks)

Option (a)
High efficiency in Induction Motor Drives due to slip control, vector control, reduced losses, and robust operation.

Option (b)
Advantages of Permanent Magnet Motor Drives: high power density, excellent efficiency, better torque at low speeds.

6. Energy Storage & Supercapacitors (7 Marks)

Option (a)
Energy storage needs for EVs: high energy density, power density, thermal stability, lifespan, safety, fast charging.

Option (b)
Supercapacitor vs Battery:

Supercapacitor = very high power density, fast charge/discharge, long cycle life

Battery = high energy density, slower charge/discharge, finite cycles

7. EV Charging Time & Startup Planning (7 Marks)

Option (a)
Factors affecting EV charging time: charger level, battery capacity, SOC, temperature, charging curves, BMS limitations.

Option (b)
Importance of business plan for EV startups: market study, cost evaluation, technology roadmap, funding, infrastructure needs, revenue model.

Overall Purpose of the Document

This exam paper evaluates a student’s knowledge of:

Basic automobile structure (chassis, body, layouts)

Electric vehicles and hybrid vehicle technology

Motor drive systems (DC, induction, PM motors)

EV controllers and control architecture

EV charging systems (Level 1, Level 2, DC fast charging)

Energy storage devices: batteries & supercapacitors

Advantages/disadvantages of EVs

Engineering thinking and practical understanding of modern automotive systems

It includes conceptual definitions, descriptive engineering explanations, system layouts, and practical EV technology questions.