EV Charging – standards-compliant platforms for the next generation of charging infrastructure

Thanks to WBG semiconductors, chargers, on-board chargers and fast-charging systems are becoming more compact, more efficient and thermally more robust. Particularly in demand at present are higher switching frequencies, smaller designs, better cooling and stronger integration of power electronics into charging infrastructure and the vehicle.

Higher efficiency reduces charging losses, lowers heat generation and thus improves the cost-effectiveness of the systems. Higher power density is important because charging hardware can deliver more power in the same space, a clear advantage for fast chargers, wallboxes and mobile applications. In the e-mobility environment in particular, robust supply chains and reliable components are regarded as a further driver for the switch to WBG technologies. WBG components in DC fast chargers typically lead to efficiency gains of around 2 to 5 per cent compared with silicon-based solutions; in individual circuit topologies, system efficiencies of over 98 per cent to just under 99 per cent are achieved. Even small jumps in efficiency mean noticeably less heat at high charging power, lower cooling effort and therefore more compact, more economical chargers.

With SiC and GaN, specialisation continues: SiC dominates where high voltages, high temperatures and high power are to the fore, for example in DC fast chargers and high-voltage systems. GaN is gaining importance above all in more compact, high-frequency chargers and in power classes where low losses and small form factors count particularly.

Connectivity in electric vehicle charging has long been more than a convenience function: it connects vehicle, charging point, backend and grid so that charging, billing, load management and in some cases plug-and-charge work together smoothly. Three trends currently dominate the industry: standardised vehicle communication via ISO 15118 with power line communication, stronger networking of charging points via wireless and wired interfaces, and the integration of intelligent control and security functions directly into the hardware.

For connectivity chips, coupling with standard-compliant protocol stacks brings clear advantages. Matter and Thread address simple, interoperable networking in the building environment, while PLC enables direct communication over the charging cable; together they simplify design, certification and scaling. System complexity also falls, because connectivity, security and protocol processing move closer together.

Particularly relevant at present are chips that support several standards flexibly and can be adapted to different charging applications by software. In demand above all are solutions for interoperable charging, secure authentication and grid-friendly load management, that is, exactly those functions that will link private, commercial and public charging points more closely with the energy system in future.

Security in electric vehicle charging has long been more than an IT topic: it protects charging points, backend, user identities and billing just as much as the availability of the grid. Various approaches and technologies are used here, from secure boot through hardware-supported key storage and trusted platform modules and secure elements to cryptographically secured firmware updates and the protection of OCPP and ISO 15118 communication. Hardware-based security offers advantages here because confidential keys are not easily readable, manipulation is detected earlier, and authentication and integrity are more robust. For EVSE, two architectures are typical: integrated security chips directly in the controller, or separate security modules as trusted anchors; both serve to protect against attacks on physical interfaces, maintenance access and remote management. Particularly relevant at present are security by design, zero-trust approaches for charging backends, and closer linking of charging infrastructure with grid and vehicle security, because the attack surface grows with every connected charging point.

Three developments are currently particularly relevant: first, trusted platform modules and secure elements are moving ever more often from a separate chip into SoCs, processors or security subsystems, that is, closer to the actual computing unit. Second, TPM 2.0 continues to gain importance, while virtual TPMs, secure enclaves and proprietary trust anchors are in greater demand. Third, secure elements are coming to the fore as compact, low-power devices for key storage, authentication and certificate functions, particularly where space, energy consumption and costs are tightly limited.

Intelligent protection and measurement modules make electric vehicle charging safer, more efficient and more grid-friendly: they detect fault currents, monitor voltage and current, and can shut down charging processes selectively in the event of overload or insulation faults. The most important trends include the detection of DC and AC faults, compact integrated sensors, higher measurement accuracy, and digital communication with charging point, vehicle and energy management. This is becoming particularly relevant for fast charging, bidirectional charging and the integration of renewable energies. For this, semiconductor manufacturers are developing high-performance SiC and GaN switches, integrated gate drivers, isolated current sensors and reference designs for compact, highly efficient chargers. Fully electronic circuit breakers with integrated sensors, control and communication are also gaining importance. For residual current monitoring, current solutions increasingly rely on residual current monitoring that detects DC fault currents and thus enables simplified protection concepts.

Edge intelligence and AI-capable microcontrollers move analysis and control directly to the charging hardware: close to the socket, power electronics and measurement data, faults can be detected earlier, charging profiles adjusted dynamically and grid peaks absorbed better. In electric vehicle charging in particular, predictive maintenance and load management are important, because outages cause expensive downtime, help minimise service call-outs and ensure stable, economical use of the existing grid connections.

Modern charging infrastructure no longer just supplies electricity; it continuously considers its environment and its own condition. Through local anomaly detection, irregularities can be identified directly in the charging system, for example unusual temperature values, current fluctuations or communication errors, before they turn into a failure. Thanks to predictive maintenance, components such as connectors, relays and communication modules are no longer only checked after a defect, but assessed predictively on the basis of their data. This makes it possible to detect wear, contact problems or unstable connections early and to plan maintenance work more precisely. Through smart charging with PV and battery integration, charging can respond flexibly to solar power, battery storage and grid load. When plenty of solar power is available, more power can go into charging; when grid load is high, it is throttled or postponed. A link with fleet and depot planning finally ensures that charging times, vehicle requirements and departure schedules are considered together. This means electric vehicles are ready at the right time with sufficient range, without unnecessarily burdening the power grid.

Semiconductor manufacturers are responding with low-power microcontrollers, integrated AI accelerators and platforms for real-time decisions at the edge, while the market increasingly sees decentrally executed AI as the next development step.