2348504_en-US

[#1]

[EasyEVSE] How to switch from AC BPT to DC BPT / Standard DC Mode in ISO 15118-20? (v4.0.4)

Hello,

I am currently developing an EVSE/EV HIL simulation platform using the rd-nxp-easyevse-imxrt106x-4.0.4 release along with the Sevenstax ISO-15118-2/20 stack on the i.MX RT1064.

According to the user manual UM11750 (Rev. 5.0), page 17: "The EasyEVSE MCU 4.0 release uses, for the HLC ISO15118-20 charging, Scheduled ControlMode and unified BPTChannel configuration in AC BPT service."

Since my research heavily focuses on commercial DC charging architectures, I need to switch the system to operate in DC BPT (Bidirectional Power Transfer) mode, or at least standard DC Charging mode under ISO 15118-20.

What I have investigated so far: I have explored the state machine in sevenstax/appl/appl-v2g.c and reviewed the configuration headers in sevenstax/configs/. While I can see macros related to charging modes (e.g., APPLV2G_EV_CONNECTION_MODE), the exact dependency chain to safely switch the entire service discovery from AC to DC without breaking the underlying hardware state machine is not entirely clear.

My Questions:
Configuration Path: Is there a supported configuration flag or macro combination within this specific release to switch the requested service from AC to DC?

Hardware Abstraction Layer (HAL) Implications: If the protocol stack is successfully forced into DC mode, are there any hardcoded HAL behaviors (such as specific PWM duty cycle checks or ADC sensing thresholds) in the EasyEVSE drivers that I must manually override to prevent state machine violations?

I want to avoid making isolated changes that might lead to unexpected fallbacks. Any guidance on the intended configuration workflow or reference documentation for DC mode would be greatly appreciated.

Re: [EasyEVSE] How to switch from AC BPT to DC BPT / Standard DC Mode in ISO 15118-20? (v4.0.4)

Hi @A1vis,

After looking into this, I arrived at the conclusion that we unfortunately do not have any guide or recommended procedure to adjust the service from AC to DC. There is not officially support flag combination, and there are several integration assumptions that Sevenstax does that would prevent the application to do a clean switch.

That is not to say that DC support is impossible by using Sevenstax, however. It just means that implementation would have to be done overriding some current integrations, including the PWM duty cycle interpretation, ADC voltage fault checks, AC presence detection, and the contactor and precharge logic.

I apologize for the inconvenience this may cause.

Re: [EasyEVSE] How to switch from AC BPT to DC BPT / Standard DC Mode in ISO 15118-20? (v4.0.4)

Hi @EdwinHz,

Thank you for the clarification.

Knowing that there is no official configuration path and that it requires significant overrides to the hardware state machine (ADC, contactor logic, etc.), I will keep the system in AC BPT mode. It is not feasible to rewrite the HAL integration for the timeline of my research.

Thanks again for helping me clear this up and saving me a lot of trial and error!