Power Supplies for Electric Vehicle Charging by Recom

Explore the Latest Automotive Technologies and Solutions from Recom exclusively at Auto EV India 2022 from 9th to 11th November 2022 at KTPO Bengaluru.

Electric vehicles and e-mobility, in general, are the future of transportation in a world that needs to reduce its carbon footprint. To make battery-powered vehicles cost-effective, electric vehicle chargers must be as efficient and economical as possible. While power conversion stages at the multi kW level are improving with the latest topologies and semiconductor technologies, AC/DC auxiliary supplies must also match the EV charger requirements in terms of efficiency and value.

Charging wall boxes and charging stations are often installed in overvoltage category three (OVC III) environments with the potential for significant dips, surges, and transients from lightning strikes, which the power supplies must also withstand. Additionally, temperature variations can be extreme, and the AC supply voltage available may be three-phase 480VAC or 277VAC. Moreover, auxiliary AC/DC modules must operate reliably in this environment along with switching regulators and DC/DC converters that provide internal voltage conversion and isolation.

RECOM provides a range of low-power AC/DC modules, DC/DC converters and switching regulators that match the battery charging application requirements for auxiliary supplies or are sources for direct low-power battery charging in portable products. RECOM’s sister company, Power Control Systems (PCS), can supply high-reliability custom battery chargers, conditioners and bidirectional inverters based on proven platform designs from three-phase AC supplies with power ratings of up to 30kW or even higher with paralleled units.

AC/DC Power Supplies

These series of 3W to 60W AC/DC converter modules have 85–528VAC input for the line to neutral connections in 100/115/230/277/400/480VAC single-phase systems or a line-to-line connection in a 120VAC system. The cost-effective and fully certified parts are available with a selection of outputs; they feature a wide operating temperature range of -40 to +85°C for harsh environments and are ideal for auxiliary supplies in battery charging and monitoring systems. These series comply with EMC standards without external filters and have low, no-load and standby consumption.

DC/DC Converters

Circuitry in battery charging applications often requires DC-DC converters to produce auxiliary rails and isolated power for communication interfaces. High-efficiency board-mounted products such as the 4:1 input 40W RP40 series and the 20W REC20 series feature six-sided shielding in 2”x1” packages, which are ideal for providing control circuitry power in charging stations and battery management systems. For lower power battery management applications, there is the 4:1 input 8-watt RP08 series, which includes parts with an input range of 160V and is suitable for strings of batteries. When a low-power 5V isolated rail is required, perhaps to provide a -5V supply for analog circuitry or for an isolated interface in a smart EV charger, the RFMM-0505 or RKE series converters are suitable; they feature 1W output, 4kV isolation, and comprehensive safety certifications.

Switching regulators

Non-isolated switching regulators provide high-efficiency replacements for linear regulators in battery charging systems. The R-78E-1.0 series, for instance, peaks at 97% efficiency, with 1-amp output current from 3.3V, 5V, or 12V outputs and input ranges up to 28V. For output power up to 3kW, the half-brick RBBA3000-50 product is a buck-boost converter, which has an input range of 9–60V and an output of 0–60V that can be preset; this can be above or below the input voltage. Its typical applications include 48V to 24V or 12V to 24V battery power conversion in electric vehicles and battery voltage stabilizers in charging stations for UAVs and drones.

Courtesy: Recom