ISSUE 011 Autumn 2021 Candela C-7 hydrofoil speedboat dossier l In conversation: Robert Hoevers l Battery recycling focus l Vehicle dynamics insight l ZeroAvia hydrogen-electric aircraft digest l Motor materials

Flat chassis chosen for axial motors Device reads LVandHV in one go URBAN VEHICLES BATTERY MONITORING Saietta has used its AFT 140 axial motor for a flat chassis for urban vehicles (writes Nick Flaherty). Mounted on the corners of the chassis, the AFT 140 in-wheel electric motors provide a torque of up to 140 Nm for controllable power at low speeds in urban stop-start journeys. The chassis is a flexible platform that can be easily connected to different frames for vehicles acting as people carriers, last-mile e-commerce delivery, mobile shops, refuse collection and inner city autonomous pods. Moving the powertrain completely into the wheels creates a perfectly flat floor with minimal intrusion into the rectangular platform. This maximises the usable space above the chassis for the vehicle’s primary purpose, whether it be for transportation, mobile retail or waste collection. A 45 V high-withstand voltage battery monitoring device for automotive designs has implemented a supply voltage-divided output for the first time (writes Nick Flaherty). Dividing battery monitoring between high- and low-voltage sources increases the safety of e-mobility designs, as it allows 12 V batteries to be monitored Using an axial flux design allows a motor with a width of 100 mm that can be placed fully in-wheel. The fully sealed AFT 140 is the first liquid-cooled axial flux motor from Saietta to go into production. The AFT 140 can also include regenerative braking, which puts energy back into the battery pack, extending the range on a single charge. by the same device that monitors the low voltages of 3.3 V powering the ECU in an EV. This is achieved by converting the high voltage into a low voltage that can be directly input to an analogue-to-digital converter. Combining three monitoring functions into a single chip also reduces the footprint required for a PCB and enhances the “We are not intending to become a platform manufacturer, and only developed a chassis to demonstrate our in-wheel motor technology,” said Wicher Kist, CEO at Saietta Group, “Ultimately we believe that inner-city EVs will be fully autonomous, and now is the time to have a serious industry discussion about the potential of in-wheel electric motors in making congested city centres quieter and cleaner.” safety of the system, as there are fewer components that might develop a fault. The A-191L/N monitor chip from Ablic also includes a circuit for controlling the supply voltage-divided output by turning it on and off to reduce standby current. This reduces the number of external parts and their footprint, and lowers the impact of manufacturing variations of external parts on monitoring accuracy. The device also monitors low-voltage lines that can be the cause of erratic ECU behaviour or failure, and overvoltage, which can damage an ECU. An input range of -30 to 45 V on the voltage sensing pin enables the device to handle overvoltage tests or tests simulating reverse connections, providing a means of monitoring the high-voltage output to an ECU by a battery or other power source. Ablic’s chip combines low- and high-voltage monitoring, enhancing system safety The Saietta motors are mounted on each corner of the chassis TheGrid 12 Autumn 2021 | E-Mobility Engineering