E-Mobility Engineering 017 l ECE Doosan electric excavators dossier l In Conversation: Matt Faulks l Battery testing focus l Battery Show North America 2022 report l Ariel Hipercar digest l Cathode materials insight l Thermal management focus

AMP showcased its Energy Management Unit (EMU), which it describes as a comprehensive solution to an EV’s every energy need. It combines the functions of a DC-DC converter, onboard charger and power distribution system with 500 A fast charge capabilities in a single enclosure, saving both space and weight, Anil Paryani explained. “`The EMU uses the latest silicon carbide and magnetics technologies to reduce the power electronics packaging volume drastically, “he added. Combining these three systems into one relies on expertise in several technologies, including wide band- gap power semiconductors and high- frequency magnetics, along with a multi-physics understanding of electrical, electromagnetic, thermal and mechanical systems, enabling engineers to co-design them. An understanding of advanced digital control and scalable embedded software systems is also critical, Paryani said. “The use of silicon carbide unlocks higher power density and efficiency, better platform scalability, and precise charging control,” he said. One result is a reduction in volume of more than 65% over comparable available solutions. This increase in power density brings cooling challenges, so the EMU is liquid-cooled and capable of accepting a wide range of flow rates. The unit can be housed within the battery pack, forming an energy subsystem, an approach that He said it is aimed primarily at applications in fully automated assembly systems in pack and module production for e-mobility, power tools, industrial vehicles, comms electronics and energy storage. In these environments, compactness, easy integration into modern control concepts and recording of key battery parameters are essential, he added. The demands on battery testing in such production facilities are high, and among them are interfaces that are easy to integrate and control, and provide fast, reliable and precise measurements and evaluations, he said. Also essential are compactness and ease of installation, along with reliably reproducible contacting of cells, and options for multi-channel measurement on very large pack, module and cell-to-pack applications. “Another aspect is the regular checking of the measuring systems, an important factor in achieving reliable, correct and reproducible results,” Giorgione said. He also emphasised that the 2511 series is easy to integrate into existing or planned control concepts through Fieldbus, supporting both cyclic and acyclic measuring options via the Profinet Industrial Ethernet comms standard. It is also possible to transmit measured values and evaluation results, and product- or order-related data via Fieldbus, and the system also enables parameterisation and complete back-up at the control level. “Measurement of the open- circuit voltage is still widespread, but it is not always meaningful as a unique criterion,” he said. “Only the determination and evaluation of the AC/DC impedance values, at 10 Hz and 1 kHz, provide information about battery quality and allow conclusions to be drawn about electrode and electrolyte properties, as these have a significant influence on the ageing process, state of charge, capacity and service life.” With up to five channels, the Burster 2511 measures open-circuit voltage and pack voltage as well as the real impedance value with configurable measurement frequencies. Made from aluminium, the modules weigh about 500 g, have dimensions of 104 x 54.6 x 120 mm, and meet the IP54 ingress protection standard. The core component is what Giorgione described as a fast and powerful microcontroller that includes a synchronous 24-bit double analogue- to-digital converter with switchable pre-amplification, and an ARM Cortex processor for internal control. “The impedance is measured according to the galvanostatic principle, the current is applied in a discharging manner, and the test object serves as the current source,” he explained. “The test object is subjected to a medium direct current using a complex process, which does not represent a load on the cell owing to the very short measurement time. Digital signal processing, various filters and arithmetic algorithms enable the real impedance value of a cell to be calculated.” Available now, the 2511 modules can be connected into a multi-channel measurement system, both physically through a DIN mounting rail or wall mounting, and at the control level through Profinet or EtherCat. ShowReport | Battery Show North America 2022 Connected to the cloud for updates, diagnostics and maintenance, AMP’s EMU serves as a DC-DC converter, onboard charger and power distribution system 46 January/February 2023 | E-Mobility Engineering