For off-highway electrification projects, the on-board charger and DC-DC converter are key parts of the vehicle’s high-voltage electrical system. Their power rating, voltage range and communication interface need to match the vehicle architecture and charging requirements.
This case study covers the application and integration of Jenwyn Tech’s 800 V bidirectional OBC + DC-DC solution in prototype agricultural and off-highway equipment developed by a European customer.
The system combines a 9.9 kW three-phase OBC with a 3 kW DC-DC converter, supporting an output voltage range of 350–800 VDC. During prototype testing, the customer evaluated the system with a Type 2 EVSE and identified several issues related to OBC wake-up and CAN-based charging control. These issues were reviewed with Jenwyn Tech’s engineering team and resolved during the integration process.
Customer Requirements
The customer is a European company working on the electrification of agricultural and off-highway equipment. For several prototype projects, the customer was looking for an integrated OBC and DC-DC solution with the following requirements:
| Requirement | Specification |
|---|---|
| OBC rated power | 9.9 kW |
| AC input | Three-phase |
| DC output voltage | 350–800 VDC |
| DC-DC converter power | 3 kW |
| System architecture | 800 V |
| OBC function | Bidirectional |
The customer planned to evaluate the system across multiple prototype projects and requested the OBC’s CAN communication protocol to integrate it with the vehicle control system.
Selecting an 800 V OBC + DC-DC Solution
Based on the required voltage and power range, Jenwyn Tech provided an 800 V bidirectional OBC integrated with a 3 kW DC-DC converter for prototype evaluation.
Combining the two functions into one system provides the vehicle with both AC charging capability and DC-DC conversion within a single integrated solution. The customer proceeded with sample testing after reviewing the technical information and product configuration.
Prototype Testing with Type 2 EVSE
After receiving the sample, the customer integrated the OBC + DC-DC system into its prototype vehicle and began functional testing.
The DC-DC converter performed as expected during the initial tests. The customer then evaluated the OBC using a three-phase AC supply and a Type 2 EVSE.
The initial OBC testing identified several integration issues related to the charging wake-up sequence and CAN-based charging-current control.
OBC Wake-Up and CAN Integration
During the initial charging tests, the OBC woke up when the charging connection was established but subsequently returned to sleep mode. The customer also observed that the charging current remained limited despite sending higher charging-current commands through CAN.
Jenwyn Tech’s engineering team worked with the customer’s engineers to review the OBC wake-up sequence and CAN communication.
The engineering review identified that the wake-up sequence also depended on the vehicle-side KL15 control. After the OBC is activated through the charging connection, the vehicle needs to control the KL15 signal within the specified time to maintain the OBC wake-up state. The OBC does not support CAN wake-up to maintain the active state.
For the charging-current limitation, the engineering review identified that both the OBC output-current request and input-current limit needed to be properly configured to allow normal charging-current control.
The original CAN protocol documentation did not include the required input-current-limit parameter. Jenwyn Tech therefore provided an updated CAN protocol for the customer’s software team.
After implementing the updated protocol, the customer repeated the charging test and confirmed that the OBC operated as expected.
Follow-Up Orders
After completing the prototype testing and resolving the integration issues, the customer placed additional orders for the OBC + DC-DC systems for its ongoing projects.
OBC, DC-DC and Integrated OBC + DC-DC Solutions
Jenwyn Tech provides OBCs, DC-DC converters and integrated OBC + DC-DC solutions for commercial EVs and off-highway applications. Our solutions are available in different power and voltage configurations to meet different vehicle electrical architectures and application requirements.
Have a specific requirement?
Email us at contact@jenwyntech.com or fill out the form below to discuss your application.