Power and discrete products for on-board charging (OBC)

As China becomes the world's largest auto sales market, the Chinese auto industry has also entered a new stage of development. In recent years, China has continuously advocated the development of energy-saving vehicles including new energy vehicles, among which electric vehicles (EV) have become a hot spot, and on-board charging (OBC) is an important part of electric vehicle applications. Today, we will tell you about OBC and the power and discrete products we can offer in this area.

EV charging solution

AC charging

• Each car has an onboard charger (OBC)

• Charging at home, work, private/public outlets

• Maximum public power charge level @ AC charging station

- 7.2kW (32A single phase), 22kW (three phase)

• Charging time:

- 3-4 hours for AC charging station 7.2kW@32A

DC charging

• Suitable for short stays and heavy charging

(for example, long trips)

• Charging capacity ≥50kW@ ≥100A

• Charging @ EV charging station

• For 80% charging, charging time usually takes 30-60 minutes

AC Charging Solutions - Overview

Car Charger (OBC) - Key Features

OBC is an AC-DC converter consisting of (PFC + isolated DC-DC) main stage

Power level up to 22kW

Input voltage

EU: 230 Vac or 400 Vac

US: 120Vac or 240 Vac

Voltage output range: 200VDC-450VDC

high efficiency

Requires AEC-Q101 power discrete device

AEC-Q100 integrated circuit needs to be

smallest size

Main module block diagram

(3ph + Neutral) input: modular approach

3x (phase to neutral) power supply advantage

The modular approach 3x (PFC + DC-DC) modules have a common input that enables:

• Simple system implementation

Very easy to change from single-phase solution to 3-phase power supply

solution.

A typical single phase topology can be used for each of the three phases.

• Higher system reliability

Charging function even if one or more modules fail

• Higher system efficiency

For partial load requests,

Only some of the three modules are connected

PFC topology and output power

PFC: Interleaved Boost

PFC: no half bridge

Totem pole

Vienna original (3 phase)

Vienna modification (3 phase)

-DC topology

DC-DC topology and power output

DC-DC: Full Bridge LLC

DC-DC: Full Bridge PS

DC-DC: Level 3 Half Bridge LLC

OBC Power Architecture: Auxiliary SMPS

Auxiliary Power: Topology vs Pout

Auxiliary power supply: flyback

ST products (power and discrete device parts) recommended for OBC

Thank you for your interest in this content.