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Susceptibility of electronic systems to the electromagnetic environment of the automotive vehicle has opened a new dimension in electronic system qualification. Electromagnetic compatibility testing of these systems must be implemented to assure proper operation in the real world. Methods of reproducing the electromagnetic environment under controlled conditions and techniques for subjecting electronic systems to this environment are reviewed. Current methods of improving system electromagnetic immunity are also discussed.

The Indian government has been promoting electric vehicles through various policy initiatives, such as offering incentives and subsidies to EV manufacturers and consumers, establishing charging infrastructure across the country, and setting ambitious targets for EV adoption. These measures aim to reduce the dependence on imported fossil fuels, mitigate air pollution, and promote sustainable mobility. As a result, the demand for electric vehicles across India is steadily increasing, and the country is emerging as a lucrative market for EVs globally. An electronically commuted brushless DC (BLDC) motor usually functions for traction in electric two-wheelers. Electric vehicles need to comply with electromagnetic compatibility (EMC) requirements. During the EMC compliance of electric two-wheelers, it is certain that the BLDC motor and its controller play an important role.

Electromagnetic compatibility (EMC) design considerations have a vital role in the proper functioning of the electronic circuits and systems of a modern off-highway vehicle (OHV). Careful planning is needed in developing the electronic systems that operate the various functions and tasks on these vehicles. Incorporation of EMC in a system design gives that system the quality of reliability; that is, the system will have reduced emissions and be less susceptible to radiated and conducted electromagnetic energy. This paper provides ideas, concepts, and guidelines that the designer of OHV control circuitry can use for incorporation of EMC at the beginning of a design project.

For an “end-to-end passenger experience that is secure, seamless and efficient” the International Air Transport Association (IATA) proposes Near Field Communication (NFC) and a single token concept to be enablers for future digital travel. NFC is a wireless technology commonly utilized in Portable Electronic Devices (PEDs) and contactless smart cards. It is characterized by the following two attributes: a tangible user interface and secured short range communication. While manufacturers are currently adapting PED settings to enable NFC in the flight mode, the integration and use of this technology in aircraft cabins still remains a challenge. There are no explicit qualification guidelines for electromagnetic compatibility (EMC) testing in an aircraft environment available and there is a lack of a detailed characterization of NFC equipped PEDs.

The ongoing energy transition will have a profound impact on future mobility, with electrification playing a key role. Battery electric vehicles (EVs) are the dominant technology, relying on the conversion of alternating current (AC) from the grid to direct current (DC) to charge the traction battery. This process involves power electronic components such as rectifiers and DC/DC converters operating at high switching frequencies in the kHz range. Fast switching is essential to minimize losses and improve efficiency, but it might also generate electromagnetic interferences (EMI). Hence, electromagnetic compatibility (EMC) testing is essential to ensure reliable system operations and to meet international standards. During DC charging, the AC/DC conversion takes place off-board in the charging station, allowing for better cooling and larger components, resulting in increased power transfer, currently up to 350 kW.

This paper provides an overview of electromagnetic compatibility considerations between battery powered, automotive type, electric vehicles and other electrical and electronic services. A brief historical background is provided along with a review of test data and available standards. The paper recommends that despite procedural difficulties, SAE J551 should be used to measure and compare electromagnetic radiation from electric vehicles. Similarly, SAE J1113 should be used to measure electromagnetic susceptibility. The paper also recommends that acceptable procedures for determining electromagnetic compatibility of electric vehicles and other services be more fully developed.

Avionics industry is moving towards more electric & lightweight aircrafts. Electromagnetic effects becomes significantly challenging as materials starts moving towards composite type. Traditional methods for controlling EMC will not be sufficient. This shift increases the complexity of in-flight hardware elements for EMI/EMC control. This paper discusses the need for EMI/EMC Control and brings out the analysis & applicability of various EMI/EMC standards in aerospace, commercial and industrial electronic products, provides comparative study with respect to levels. The study include various sections of DO-160 and applicable guidelines for controlling EMI/EMC with respect to LRU (Line Replaceable Unit) & wire/cable harnesses. Also presents guidelines with respect to shielding of components, selection of components, grounding schemes, filter topologies and layout considerations.

The key words in the marketplace for off-highway vehicles are durability, performance, and efficiency. A manufacturer of these vehicles recognizes that one way to successfully address these needs is by a well thought through electronics design. With the computer sophistication now being incorporated into off-highway vehicles, engineers must work closely to assure electromagnetic compatibility (EMC) of the entire system. A properly established EMC program extending from concept to final design will support each of a product's specified operations and still function as an integrated whole. This paper describes the process for designing the EMC for an off-highway vehicle.

Electromagnetic immunity (EMI) for off-highway vehicles (OHV) is a vehicle's ability to resist radiated and conducted electromagnetic interference. Interference can originate within the OHV from the various systems designed to control its operational functions; external sources can also cause serious disruption of the electronic control mechanisms. Knowledge of how and where interferences originate gives the electronic designer insight into how to avoid the pitfalls which can cause malfunctions. Verification of designs through testing will ensure that safety and reliability are built into every OHV produced. This paper discusses the mechanisms that cause susceptibility of electronic circuits to electromagnetic interference, and presents test methods to help the designer improve circuit design and verify the immunity of the complete vehicle. This is the second in a series of papers on electromagnetic compatibility (EMC) in the off-highway vehicle.

Electromagnetic emissions (EME) from vehicles and their effect on broadcast radio and television were studied as early as 1944. Their original effect was significantly reduced by the early 1960s. Today, ignition noise (broadband) and vehicular micro-processor-controlled system noise (narrowband) are interfering with Land Mobile (two-way) communication services and other devices such as computers. Two SAE test methods, J551 and J1816, are used to measure this EME. Under development are methods to measure conducted EME on vehicle signal wiring and power input leads. This paper discusses EME measurement methods, provides insight into the sources of EME problems, and gives information on the test instrumentation used to make these measurements. This paper is the third in a series of papers on electromagnetic compatibility (EMC) in the off-highway vehicle. The first paper was an overview of a complete EMC program with discussion of several important segments.

This paper describes a systematic decision making process applied to the field of Electromagnetic Compatibility of automotive vehicles. It identifies objectives and classifies them by priority. It describes various mechanizations of possible assurance methods. A matrix of alternate mechanizations and objectives which they meet is assembled and the best alternate is identified.

One of the challenges of automotive designs which utilize heat reflecting glazing is the conductivity of the reflective coating. Significant attenuation of electromagnetic energy occurs when devices which send or receive signal through the glazing are mounted on or very near heat reflecting windows. A number of methods are available to maintain electromagnetic compatibility and the function of these and other devices in the passenger compartment which communicate with devices outside of the vehicle.

As the volume and complexity of electronics increases in automobiles, so does the complexity of the electromagnetic relationship between systems. The reliability and functionality of electronic systems in automobiles can be affected by noise sources such as direct current (DC) motors. A typical automobile has 25 to 100+ DC motors performing different tasks. This paper investigates the noise environment due to DC motors found in automobiles and the requirements that automobile manufacturers impose to suppress RF electromagnetic noise and conducted transients.

Project Oculus, an experimental configurable sensor platform for deploying airborne sensors on a C-130 aircraft, is currently in its pre-flight testing phase. The electronics driving the platform are available commercially off the shelf (COTS) and as such are not automatically rated to comply with stringent military electromagnetic standards as defined in MIL-STD-461. These COTS electronics include efficient switching power converters, variable frequency motor drives (VFD), and microprocessor based equipment, all of which can present electromagnetic interference (EMI) issues. Even in a design where EMI issues were not considered up front, it is often possible to bring the overall configuration into compliance. Switching and digital clock signals produce both conducted and radiated noise emissions. Long cable runs and enclosure apertures become noise transmitting antennas. Large switching currents place noise on the power lines causing interference with other equipment.

Most electronic systems, including electric motor drives and electric power conditioners, require the use of electromagnetic devices, such as inductors and transformers as circuit components to carry out any of the following functions: a) Suppressing or isolating specific harmonic components in voltages and currents. b) Providing electrical isolation from one circuit to another. c) Limiting the currents under fault conditions. d) Increasing or decreasing the voltage or current levels. e) Integrating voltages, currents, or power. f) Providing neutral line, phase shift. The performance of the electronic systems is dependent upon the design of the electromagnetic components that are used. For the aerospace quality hardware, the weight, size, cost, reliability, and efficiency of the electronic systems are substantially dependent upon the design of electromagnetic components.

This paper discusses design and testing of a regulated dual voltage automotive electrical system that provides both 48 and 12 volt subsystems. The paper focuses on the design, performance, and manufacturing differences between 12 volt and 48 volt electromagnetic components for vehicle applications. Dual voltage systems have inherent benefits of lower current consumption, smaller/lighter wiring harnesses, and potential improvement in system efficiencies. These benefits help some automotive operations, but are not readily transferred to the electromagnetic product arena.

Insuring conducted Electromagnetic Compatibility (EMC) of electronic components from DC to 200 MHz can be determined through analytical prediction techniques and empirical data reduction. For analytical modeling and prediction of automotive electrical/electronic systems, there are two main analytical techniques which can be used. From DC to approximately 500 KHz, conventional circuit analysis lumped parameter networks are implemented. From 500 KHz to 200 MHz, transmission line theory using linear passive networks are employed.

In the sensitive automotive applications like the safety restraint systems (SRS), twisted lines can be used to link the components of the system because of their property of reduction of the electromagnetic interference (EMI) coupling. Compared to the parallel lines, the twisted lines present the drawback to consume more copper in their manufacturing due to the greater length of their conductors. A parametric study based on the numerical modeling and the measurement of twisted lines is conducted in order to analyze the effect of the twisting pitch and of the untwisted part of these lines on the level of EMI coupling. This study will enable to optimize these two parameters in order to reduce the level of EMI coupling as well as the length of the conductors of the lines.

The electromagnetic coupling between a conductor and a composite structure by wire-mesh techniques using method of moments is investigated. A three-bladed composite panel with an aluminum tube located above the panel is considered in this analysis. Computations are made of the current on the tube for various frequencies with height above the panel as a parameter. The numerical results compared reasonably well with the measurements. The technique proves to be useful in modeling the composite structures such as wings of an aircraft.

The electromagnetic dent removal process removes dents from many aluminum structures where access is either limited to one surface (e.g., bonded aluminum honeycomb parts) or where access to the rear surface is restricted by equipment or other structures.