KTC Leads Standardization of Communication Protocols for EV Fast-Charger Power Modules
Reducing Protocol Implementation Burdens and Establishing a Data-Driven Management System for Aging Chargers
The Korean Testing Certification Institute is developing a communication protocol standard for power modules, a core component of electric vehicle fast chargers. Based on the standard, the Institute will establish a data-driven management system for aging charging equipment.
Domestic and international standards already cover communications between electric vehicle chargers and vehicles, as well as communications between chargers and servers.
However, no common standard currently exists for communication between the controller and power modules inside a charger.
Each power module manufacturer uses a proprietary Controller Area Network protocol, making interoperability between products from different manufacturers difficult.
Whenever a power module is replaced, the applicable protocol must be redeveloped. This process generally takes six months and creates a serious bottleneck in infrastructure maintenance.
In addition, the initial fast chargers installed mainly between 2016 and 2018 are reaching their expected service life of eight years.
Under the existing management method, chargers may be removed and replaced solely according to their age, regardless of their actual operating condition.
To address these issues, the Korean Testing Certification Institute will undertake three core tasks: communication protocol standardization, data consistency validation, and the establishment of an aging Health Index.
First, data exchanged between controllers and power modules will be classified into three categories: mandatory data related to safety and aging, recommended data, and optional data. The upper communication layer will then be standardized.
Error codes will be directly mapped to the L0-to-L4 severity levels of the international Open Charge Point Protocol 2.0.1 to prevent conflicts between upper layers.
The Institute will conduct two-by-two cross-tests between different devices and black-box evaluations under actual operating conditions, verifying more than 2,000 combinations.
It will also trace the entire communication process to confirm that fault codes generated by power modules reach the Charging Station Management System within 10 seconds without omissions.
A data-based comprehensive Health Index will be introduced for aging charger management.
The Health Index will analyze degradation factors including cumulative operating time, thermal stress, repeated load fluctuations, and deterioration in cooling performance.
Based on the index, management guidelines will determine whether a charger should remain in operation, undergo partial component replacement, or be fully replaced.
The Korean Testing Certification Institute plans to complete the communication protocol standard development by April 2027.
Once standardization is completed, protocol development time is expected to decrease from six months to one or two months. Power modules from different manufacturers will also become interchangeable, significantly improving maintenance efficiency.
Accurate sensing data such as temperature and efficiency will help prevent safety incidents, including fires caused by overvoltage and overheating.
Condition-based component replacement using an objective Health Index will also reduce unnecessary expenditures.
President Sung-il Ahn of the Korean Testing Certification Institute stated that the Institute would cooperate closely with charger manufacturers, the Korea Environment Corporation, and relevant experts to develop a reasonable standard based on technical evidence.
He added that the aging charger management guidelines established through successful validation would play a central role in ensuring the stable operation and advancement of Korea’s electric vehicle charging infrastructure.
