EX-703-A Hybrid & Electrical Vehicles - Jun 2025 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aWhat are the major factors affecting the stability of a vehicle? How do you calculate EV efficiency?
   How to answer

   • List stability factors: CG height, wheelbase, track width, weight distribution, suspension, tyres, aerodynamics
   • Explain rollover, understeer/oversteer and road conditions
   • Define EV efficiency as useful mechanical energy / electrical energy input
   • Give calculation method: range per kWh, Wh/km, drivetrain and charging losses
2. 7 Marks
   bExplain the components of hybrid electric vehicles. Write the disadvantages of a hybrid electric vehicle system.
   How to answer

   • List HEV components: ICE, motor/generator, battery, power electronics, transmission
   • Explain function of each component and energy flow
   • Discuss advantages briefly for context
   • List disadvantages: cost, complexity, weight, maintenance, battery disposal
3. 7 Marks
   aExplain the social and environmental impacts of hybrid and electric vehicles.
   How to answer

   • Define social impacts: employment, public health, noise, accessibility, acceptance
   • Define environmental impacts: tailpipe emissions, lifecycle CO2, battery mining/recycling
   • Compare HEV vs BEV vs ICE on emissions and resources
   • Conclude with sustainability trade-offs
4. 7 Marks
   bWhat are the implications of electric vehicles charging at night on the electrical grid? Would additional capacity be needed if everyone did this around peak hours?
   How to answer

   • Explain night charging: off-peak load, load levelling benefit
   • Discuss grid impacts: transformer loading, harmonics, distribution constraints
   • Analyze peak-hour simultaneous charging need for additional capacity
   • Mention smart charging, TOU tariff and load management solutions
5. 7 Marks
   aWhat is the difference between AC traction and DC traction locomotives? Why does AC current generated in diesel-electric locomotives get rectified and then inverted for the AC traction motors?
   How to answer

   • Differentiate AC vs DC traction: motor type, control, maintenance, efficiency
   • Explain diesel-electric generation: alternator produces variable frequency AC
   • Explain rectification to DC link then inversion to variable VVVF AC
   • State benefits: precise speed-torque control for AC traction motors
6. 7 Marks
   bWhat is power flow control in electric drive train topology? Explain the purpose of the power split in the series parallel hybrid powertrain.
   How to answer

   • Define power flow control in electric drivetrain topology
   • Describe series, parallel and series-parallel power paths
   • Explain power split device function and operating modes
   • State purpose: optimize ICE efficiency, enable e-CVT and regenerative braking
7. 7 Marks
   aExplain configuration and control of dc motor drives in electric vehicles.
   How to answer

   • Show DC drive configuration: battery, DC-DC chopper, DC motor
   • Explain armature and field control methods
   • Describe four-quadrant operation and regenerative braking
   • Discuss advantages and limitations in EVs
8. 7 Marks
   bExplain configuration and control of Permanent Magnet Motor drives in electric vehicles.
   How to answer

   • Show PMSM/BLDC drive configuration: battery, inverter, controller
   • Explain field-oriented / vector control and position sensing
   • Describe torque-speed characteristics and flux weakening
   • State advantages: high efficiency, power density for EVs
9. 7 Marks
   aExplain the factors to be considered while selecting energy storage technology for hybrid electric vehicle.
   How to answer

   • List selection criteria: energy/power density, cycle life, cost, safety, temperature
   • Explain weight, volume, charging rate and efficiency considerations
   • Relate to HEV duty: peak power, regenerative capture
   • Conclude with trade-off selection methodology
10. 7 Marks
    bExplain super capacitors based energy storage system in hybrid electric vehicles. Why are supercapacitors used in electric vehicles?
    How to answer

    • Describe supercapacitor construction and high power density principle
    • Explain integration with battery via DC-DC converter
    • State roles: peak shaving, regenerative braking, fast charge-discharge
    • Explain why used: long cycle life, high efficiency, battery life extension
11. 7 Marks
    aWhat are the pros and cons of a hybrid car having two batteries? How would they make a hybrid battery and supercapacitor work together in electric cars?
    How to answer

    • Explain dual-battery concept: high-voltage traction + 12V auxiliary or dual chemistry
    • List pros: redundancy, load sharing, efficiency; cons: cost, weight, complexity
    • Describe battery-supercapacitor hybrid: power vs energy split
    • Explain control via DC-DC converter for peak and regenerative power
12. 7 Marks
    bExplain different energy storage techniques used in hybrid electric vehicles.
    How to answer

    • List techniques: lead-acid, Li-ion, Ni-MH, supercapacitor, flywheel, fuel cell
    • Compare energy/power density, life, cost in table form
    • Explain suitability for HEV applications
    • Conclude with current trends toward Li-ion + ultracapacitor
13. 7 Marks
    aExplain the most important factors when selecting an energy storage system for EV charging?
    How to answer

    • List factors: capacity, power rating, C-rate, cycle life, DoD, cost, safety
    • Explain charging speed, grid compatibility and thermal management
    • Discuss sizing for peak demand and renewable integration
    • Mention standards and lifecycle considerations
14. 7 Marks
    bWhat is the "building energy management system" and what would be the advantages? How does an energy management system work?
    How to answer

    • Define BEMS: monitoring and control of building energy use
    • List advantages: energy saving, cost reduction, comfort, demand response
    • Explain working: sensors, controllers, software optimization
    • Mention integration with EV charging and renewables
15. 7 Marks
    aWhat are the classification of energy management strategies? Explain the latest trends in energy management technology.
    How to answer

    • Classify strategies: rule-based, optimization-based, predictive, AI-based
    • Explain latest trends: V2G, smart grid, IoT, machine learning
    • Discuss efficiency, real-time control and renewable integration
    • Give examples of applications
16. 7 Marks
    bWhat are the barriers of energy management? Explain the issues with energy management strategies.
    How to answer

    • List barriers: high cost, lack of awareness, technical, policy, behavioral
    • Explain issues: data uncertainty, complexity, interoperability, investment risk
    • Discuss impact on adoption of strategies
    • Suggest mitigation measures