Wanda Group launches industrial light electric vehicle charger solution based on ST products

On August 17, 2023, WPG Holdings, a leading international semiconductor component distributor dedicated to the Asia-Pacific market, announced that its subsidiary Youshang has launched an industrial light electric vehicle charger solution based on STMicroelectronics (ST) STDES-2KW5CH48V.

Figure 1- Display board of Dalian Dayoushang's industrial light electric vehicle charger solution based on ST products

With the advancement of battery technology, industrial light electric vehicles have begun to make breakthroughs in various fields. As one of the essential supporting products for these electric vehicles, chargers are also constantly innovating in this electrification trend. The industrial light electric vehicle charger solution launched by Dalian Dayoushang based on ST STDES-2KW5CH48V can operate within the input power voltage range of 85-265VAC, and when the input voltage is higher than 180VAC, it can also obtain an output power of up to 2.5KW. This solution is suitable for various industrial light electric vehicle charging systems, including products such as electric bicycles, electric rickshaws, forklifts, micro electric vehicles or industrial logistics robots.

Figure 2-Application scenario of Dalian Dayoushang's industrial light electric vehicle charger solution based on ST products

STDES-2KW5CH48V is a reference design launched by ST for industrial light electric vehicle chargers. This charger can be used to charge lithium-ion batteries and lead-acid batteries to meet the latest trend of current battery charging. This reference design integrates many ST products. Its boost power factor correction (PFC) circuit is controlled by L4984D, providing a high power factor (PF) greater than 0.9. The DC-DC circuit of the full-bridge LLC resonant power converter is controlled by L6599A. In terms of output rectification, high-performance diodes and the LLC transformer secondary winding with a center tap configuration are used to improve overall energy efficiency.

In addition, the design uses an STM32F072CB microcontroller to control the power stage and battery charging profile, with a user interface and management protection functions. In the PFC stage, MDmesh M5 power MOSFETs and SiC diodes are selected. In the LLC stage, MDmesh DM6 power MOSFETs are applied. While the primary and secondary parts are powered by an offline flyback circuit based on VIPER16.

Figure 3-Block diagram of DaLian DaYouShang's industrial light electric vehicle charger solution based on ST products

Formal testing and measurements have confirmed that this solution has excellent performance. Combining comprehensive capabilities with digital control, it can provide high efficiency, near unity power factor and low THD over a wide range of input voltage and load conditions.

In addition, if a higher battery voltage design is required, this solution requires almost no hardware modification. The entire primary side (PFC stage, DC-DC full-bridge LLC) remains unchanged. Only the output voltage detection resistor needs to be modified on the secondary side.

Core technology advantages:

 L4984D: continuous current mode power factor controller;

 L6599AD: dual-switch half-bridge resonant controller;

STM32F072CBT6 : mainstream Arm Cotex-M0 USB MCU with 128KB flash, 48MHz CPU, USB, CAN and CEC functions;

 STW57N65M5: N-channel 650V, 56mohm (typ), 42A MDmesh M5 TO-247 package;

 STO67N60DM6: N-channel 600V, 48mohm (typ), 58A MDmesh DM6 TO-LL package;

 STPSC20H065CW: 650V, 20A, dual-group higher surge voltage SiC diodes;

VIPER16HN : VIPerPlus series, energy-saving 6W high-voltage converter with direct feedback.

Program Specifications:

 Input AC voltage: 85 to 265VAC;

 Peak efficiency at 1.75KW load: >93.5%;

Peak efficiency at full load: >93%;

 PFC output voltage: 415V±2%;

 PFC operating mode: CCM;

 PFC controller: L4984D;

Power factor within input voltage range 85-265VAC: >0.97, for load>20%;

THD within input voltage range 85-265VAC: <10 >20%;

Maximum output power: 2.5KW (European voltage range), 1.25KW (US voltage range);

 DC-DC converter: full-bridge LLC;

LLC power converter frequency range: 90-160KHz;

Start : soft start;

Rectifier topology: center tap;

 Cooling: forced air;

 Protection: low input voltage and high input voltage, low output voltage and high output voltage, output over current and short circuit protection.