Electrical Interview Questions in Automotive and Aerospace

01). Explain the fundamentals of electrical power generation & distribution in an aerospace.

All aerospace electrical systems contain components that can generate energy. Generators or alternators, depending on the aircraft, are used to generate power. These are often powered by an engine, although they can additionally be generated by an APU, a hydraulic motor, or a Ram Air Turbine (RAT).

02). Describe the distinctions between automotive & aerospace electrical systems.

03). What function does electromagnetic compatibility (EMC) perform in the design of aerospace and automotive electronics?

The capacity of electronic equipment to function in its intended environment without generating or being impacted by electromagnetic interference (EMI) is known as electromagnetic compatibility (EMC). In order ensure the safety and dependability of the systems, EMC is essential in the design of electronics for aerospace and automotive.

The following list of factors illustrates the significance of EMC in the design of automotive and aeronautical electronics:

• To prevent essential systems, such flight control and engine management systems, from being negatively impacted by EMI.
• in order to avoid the systems emitting EMI that might interfere with nearby electronic equipment.
• It is essential that the systems can function well in challenging conditions, such as when other EMI sources are present or when it is extremely hot or cold.

EMC testing is an important process in the design of electronics for both aerospace and automobiles. EMC testing is utilised to both confirm that the systems comply with the necessary EMC requirements and to detect possible problems that require to be fixed.

04). Describe the function of sensors in automotive & aerospace systems.

Sensors measure physical values in automotive and aeronautical systems. Sensors measure engine RPM, vehicle speed, fuel level, air temperature, and tire pressure in automobile systems. Sensors assess aircraft altitude, airspeed, attitude, and engine temperature in aeronautical systems.

Electronic control units (ECUs) control vehicle or aircraft systems using sensor data. The ECU controls fuel injection & ignition using engine RPM sensor data. The ECU controls transmission and braking with vehicle speed sensor data.

Automotive & aerospace systems need sensors for safety and efficiency. Sensors measure physical quantities and inform ECUs to keep systems within design limitations.

• Engine RPM sensor: Measures crankshaft speed. This information controls fuel injection & ignition for the ECU.
• Vehicle speed sensor: Measures vehicle speed. This information controls the ECU’s transmission & braking systems.
• Fuel level sensor: Measures fuel in the tank. This data is utilized by the ECU to compute fuel economy and warn drivers of low fuel.
• Air temperature sensor: Measures engine air temperature. This information controls fuel mixture and ignition timing by the ECU.
• Tire pressure sensor: Measures tire pressure. This information alerts the driver to low tire pressure by the ECU.

05). What differences exist between the power distribution of automotive and aerospace electrical systems?

06). Discuss the difficulties and factors that must be taken into consideration when designing electrical systems for high-altitude aerospace applications.

Difficulties and factors while developing high-altitude aeronautical electrical systems:

• Low air pressure: High-altitude air pressure is substantially lower than sea level. This can damage electrical component insulation, making them less resistant to arcing & other failures.
• High humidity: High heights have higher humidity than sea level. Electrical insulation and metal corrosion might also be affected.
• Radiation: At high altitudes, aircraft are subjected to cosmic and solar radiation. Radiation damages electronics and components.
• Vibration: Flight causes a lot of vibration. This vibration might loosen electrical connections and cause other problems.
• Size and weight restrictions: Electrical systems must be lightweight and small for aerospace systems due to weight and dimension constraints.
• Redundancy: Aircraft electrical systems must be extremely redundant to continue operation after failure. Multiple generators, batteries, and power distribution buses are needed.

07). What are the primary safety measures and standards in force for automotive and aerospace electrical systems?

Fundamental security measures and requirements for automotive and aerospace electrical systems are:

• Functional safety: This systematic method ensures that electrical systems operate safely even if they fail. ISO 26262 is the most popular automotive functional safety standard. The most used aerospace standard is DO-178C.
• Protection: Fuses & circuit breakers prevent electrical system overloads and other risks. Safety-critical systems need protection.
• Testing: Electrical systems are rigorously tested for safety. This testing involves functional and environmental testing including vibration and temperature.
• Qualification: Electrical systems should be qualified for safety. Third parties usually qualify.

These are some of the automobile and aerospace electrical system safety regulations. These standards allow engineers to design and implement secure & reliable electrical systems which protect people and property.

08). Explain the concepts of fault tolerance and redundancy as they pertain to electrical systems in aerospace.

Aerospace electrical system design emphasizes fault tolerance and redundancy.

• Fault tolerance allows a system to maintain operating after a failure. Redundant systems or components can do this. An aerospace may have two generators to supply power if one fails.
• Duplicating components or systems is redundancy. This means each component (or) system has numerous copies so it can still work if one fails. Aerospace safety-critical systems like flight control require redundancy.

Redundancy in aerospace electrical systems depends on criticality. The flight control system is more redundant than the lighting system.

09). How is thermal management addressed in automobile and aerospace electrical systems?

Thermal management in the electrical systems can be handled in a variety of ways. Among the most popular techniques are:

• Heat sinks: These are objects that dissipate heat from components. Typically, they are constructed from metal with an excellent thermal conductivity.
• Fans: By moving air over the components, fans assist in removing heat.
• Fluid cooling: To remove temperature from electrical components, a liquid—such as water or oil—is used in fluid cooling. Compared to air cooling, this technique of heat transmission is more effective.
• Active cooling: Pumps or fans are used in active cooling to move a fluid throughout the components. Although this is the most effective way to transfer heat, it is also costly to use.

Depending on the particular application, a particular thermal management technique is employed. For example, air cooling is often used in automotive applications while fluid or active cooling may be used in aeronautical applications.

10). Describe the common communication protocols used in automotive and aerospace electronic systems?

The basics of automotive & aerospace electronics communication protocols:

Automotive:

• CAN (Controller Area Network): A popular protocol for automobile ECU connection. As a broadcast protocol, all bus ECUs are capable of receiving all messages. Transmission control, engine control,  & body control use CAN.
• Flex-Ray: A high-speed protocol for deterministic applications like ABS and ESC. High-performance vehicles are adopting Flex-Ray, which is less popular than CAN.
• LIN (Local Interconnect Network):  A inexpensive, low-speed protocol for sensor-actuator communication. Lin is less prevalent than CAN (or) Flex-Ray, yet it is growing as electronics get cheaper.
• Ethernet: A standard networking technology used in vehicle electronics. Ethernet is becoming more prevalent in automobile applications as data transfer increases.

Aerospace:

A serial protocol for avionics system communication. Many aeronautical components and systems accept this protocol.

• MIL-STD-1553: Avionics system serial protocol. This protocol is more reliable than ARINC 429 & used in critical applications.
• Ethernet: As data transfer rises, aircraft applications are also using Ethernet. Ethernet is appropriate for flight control & avionics displays because it has better bandwidth & lower latency than ARINC 429 & MIL-STD-1553.

11). Explain the significance of power electronics in electric vehicles and airplanes.

EVs and aerospace have advantages from power electronics in the following ways:

• Efficiency improvement: By more effectively converting and managing electrical power, power electronics can contribute to EV and aircraft efficiency gains. Better fuel economy & lower emissions may result from that are involved.
• Increased power density: By enabling the utilization of smaller, lighter components, power electronics can aid in raising the power density of EVs & aircraft. This could enhance these cars’ efficiency and range.
• Weight reduction: By using lighter parts, power electronics can contribute to EV and aircraft weight reduction. This can enhance these vehicles’ performance and fuel efficiency.
• Increased dependability: By employing more durable components and providing stronger protection against failures, power electronics can assist to increase the dependability of EVs and airplanes.

12). What function do power converters and inverters perform in electric vehicles and aerospace?

Power Converter:

A power converter is a device that transforms one type of electrical energy into another. Electricity converters are used in electric vehicles to change the battery’s DC electricity into the AC power the electric motor requirements. Power converters are used in aerospace to transform the AC power produced by the generators into the DC power needed by the aerospace’s electrical systems.

Inverter:

To change DC electricity into AC power, inverters are employed. Inverters are used in electric vehicles to transform the DC power supplied from the battery to the AC power needed by the electric motor. Inverters are devices used in aerospace to convert DC power from batteries to the AC power needed by the aerospace’s electrical systems.

Inverters and power converters are essential parts of electric vehicles & aerospace. They enable these vehicles to efficiently and safely transform and control electrical power. This is necessary to maintain the effectiveness, efficiency, and dependability of these vehicles.

13). What are the primary components of an aerospace electric propulsion system and how do they interact?

The primary components and their functions in an aeronautical electric propulsion system:

• Power source: The power source supplies the propulsion system’s electrical energy. This could be a nuclear reactor, a solar array, (or) a battery.
• Thruster: The device that produces thrust is known as a thruster. Ion thrusters, Hall thrusters, & plasma thrusters are merely a few of the many thrusters that can be employed in the aerospace electric propulsion systems.
• Power electronics: Energy from the power source is converted by the power electronics into the voltage & current needed by the thruster.
• Control system: The propulsion system is operated by the control system. This entails managing the thruster’s power, voltage, & current in addition to its pointing.

The aerospace vehicle’s thrust is produced through the interaction of the power source, thruster, power electronics, & control system. The power electronics transform the electrical energy from the power source into the voltage & current that the thruster requirements. The thruster’s functioning is then governed by the control system to deliver the required amount of thrust.

14). Discuss battery technology advancements and their impact on electric vehicles and aerospace applications.

Some battery technology developments and their effects on electric vehicles & aerospace:

• Lithium-ion batteries:The most popular battery type in electric vehicles & aerospace is lithium-ion. They store a lot of energy in a tiny space due to their high energy density. They are lightweight, which is vital for aerospace. However, lithium-ion batteries are expensive and short-lived.
• Solid-state batteries: This intriguing new technology could replace lithium-ion batteries. They outperform lithium-ion batteries in energy density and stability. However, solid-state batteries remain in research and not yet commercially viable.
• Graphene batteries: Graphene batteries are yet another emerging technology. The substance is graphene, which is strong and lightweight. Graphene batteries charge quickly and have great energy density. Yet, graphene batteries are still in development and not yet commercially viable.

Battery technology advances are affecting electric vehicles and aerospace. They enable electric vehicles with extended ranges and faster charging. They also enable more efficient & powerful aeronautical electric propulsion systems.

15). How can electromagnetic interference (EMI) in aerospace and automotive electrical systems be mitigated?

Techniques to reduce EMI (electromagnetic interference) in aerospace & automotive electrical systems:

• Filtering: EMI filters block or attenuate signals. They’re usually connected to electrical power and signal cables.
• Grounding: EMI currents run through a low-impedance grounding channel, preventing it.
• Shielding: EMI-blocking materials are shielding. It shields sensitive electronics from EMI.
• Layout:  Electrical systems may be laid out to reduce EMI. Avoid lengthy, unshielded cables and keep sensitive components from EMI sources.
• Design: EMI-resistant electrical systems may be constructed. Differential signalling and EMI-resistant components are examples.
• Testing: EMI testing verifies electrical system EMI compliance. Many EMI test devices are used for this testing.

16). Describe the concept of fly-by-wire technology in aerospace and its evolution over time.

Fly-by-wire technology, which is the replacement of all mechanical linkages between the pilot’s control stick & the control surface actuators. By electrical signal cables, provides a practical and logical solution to many of the control system difficulties associated with contemporary high-performance aircraft & aerospace vehicles.

17). Describe how electrical systems and control systems are integrated in autonomous vehicles and aircraft.

Electrical systems:

Autonomous cars and aircraft use electrical systems to power and control actuators, sensors, & other components. A typical system includes batteries,  inverters, power converters, & controllers.

Control systems:

Control systems in automobiles and aerospace move and operate them. These systems usually have sensors, actuators, and controls.

Aerospace and autonomous vehicles have tightly integrated electrical and control systems. The control systems operate the electrical systems, which supply power and control signals.

18).How is avionics used in aerospace & how is it vary from automobile electronics?

Avionics systems are distinct from automotive electronics in several ways:

• Environment: Avionics systems must work in high temperatures, humidity, & vibration. However, automotive electronics are usually more controlled.
• Weight and size: Avionics systems should be light and small to reduce airplane drag. In automotive electronics are less weight- and size-restricted.
• Reliability:   To ensure aerospace safety, avionics equipment must be highly reliable. Automotive electronics don’t need the same reliability.

19). Describe power factor correction (PFC) and its application in automotive and aerospace power systems?

PFC – Power factor correction improves AC power factor. In an AC circuit, power factor is the ratio of the actual power to apparent power. The true power is the load’s actual power, whereas apparent power represents the circuit’s overall power.

In order to increase the efficiency of the systems, PFC is employed in automotive & aerospace power systems.

• PFC can be used in an automotive power system to increase the alternator’s efficiency, which is the component that creates energy to power the automobile’s electrical systems.
• PFC can be used in an aerospace power system to increase the effectiveness of the generators, which produce the electricity needed to power the aerospace’s electrical systems.

20). How do automotive and aerospace differ in terms of electrical system?

21). What environmental factors and regulations govern the electrical systems in automotive and aerospace?

Several environmental factors and regulations that impact automotive & aerospace electrical systems:

Automotive electrical systems:

• Environmental conditions: Automotive electrical systems are usually kept between -40°  & 120° Fahrenheit. But they may also experience adverse conditions like salt spray or excessive humidity.
• Regulations: The (FMVSS) – Federal Motor Vehicle Safety Standards & Environmental Protection Agency (EPA) regulate automotive electrical systems.

Aerospace electrical systems:

• Environment:  Extreme temperatures, vibration, humidity, & radiation are common in aerospace electrical systems.
• Regulations: FAA and EASA regulations govern aerospace electrical systems.

22). What safety concerns are specific to electrical systems used in aerospace?

Because of their distinctive operating conditions, electrical systems utilized in aerospace are subject to particular safety concerns. For instance, electrical systems in the aerospace applications frequently experience abrasion, vibration, and high altitudes. These conditions can increase the possibility of failure and add additional stress on the electrical systems and components.

Electrical systems used in aviation applications have been designed with characteristics like insulation, shielding, & redundancy to solve these safety concerns. These elements contribute to the aircraft’s safety by helping to shield the systems from harm and malfunction.

23). Which three component parts constitute the electrical system of the aerospace?

The three main parts of your aerospace’s electrical system are

• A battery,
• A generator or alternator, and
• An electrical bus for power distribution.

Engine-driven magnetos in approved piston aircraft engines power the spark plugs, therefore no external electrical power is needed for the engine to work.

24). How electrical grounding & shielding are used in aeronautical applications?

Electrical grounding:

To stop the accumulation of static charge, electrical grounding is necessary. If static electricity is not correctly discharged, it may result in flames or explosions. Static electricity is securely transmitted to the earth because of electrical grounding.

Shielding:

Shielding is important for EMI protection of electrical systems and components. Electrical systems may experience noise or other disturbances from EMI, which can make them malfunction. EMI is prevented from getting to the electrical systems and components with the use of shielding.

Shielding and electrical grounding are frequently combined in aircraft applications. Shielding contributes in preventing EMI from damaging the electrical systems and components, and electrical grounding creates a channel for electricity to flow in the case of a short circuit.

Aerospace engineers can contribute to the safety of the electrical systems in aircraft by adopting electrical grounding and shielding.

25). In an electric vehicle (EV), what function does the (BMS) – battery management system  provide? Why is it significant and how does it function?

A Battery Management System (BMS), is a system that controls the electronic components of a rechargeable battery, whether it be a cell or a battery pack, becomes an essential component in the process of assuring the safety of electric vehicles. By keeping the cell remains within its safe working limits at all times, it protects not only the user but also the battery itself.