simulating DC Coupled BESS

Hi

Im trying to build a DC coupled PV + BESS simulation. My objective is to simulate both AC and DC coupled systems with the same parameters and then compare the efficiencies of both at each stage.

I was able to find a "Peak Shaving with BESS" demo in the Simscape examples but as per my understanding, that represents an AC coupled system.

My main issue is that I am not sure how to work around that Peak Shaving example to simulate a DC coupled system.

Also, I understand that there are multiple types of DC coupling such as - Conventional, Reverse or Hybrid. I just need assistance for any one model, preferably the Conventional DC Coupled BESS system. Once I understand the basics of how to build it I can learn and replicate it for the rest.

Also, an unrelated doubt - is the system presented below also a valid DC coupled PV+BESS system? Why?

source: https://doi.org/10.1109/PVSC.2018.8547329

Best Regards

Prakhar

[Raag]

Hi,

It is my understanding that you are trying to adapt an AC-coupled PV + BESS Simscape example (such as peak shaving with BESS) to model a DC-coupled PV + BESS system, and are looking for guidance on how to structure the DC-coupled configuration.

I recommend starting from the architectural difference between AC and DC coupling. In a conventional DC-coupled system, both the PV array and the battery are connected to a common DC bus through their respective DC/DC converters, and a single inverter stage interfaces this DC bus to the grid. To build such a configuration, you may consider:

• Interface PV via an MPPT-controlled DC/DC converter
• Interface BESS via a bidirectional DC/DC converter for charge/discharge control

Regarding your reference diagram, since both PV and battery connect to a common DC stage before inversion, it is consistent with a typical DC coupled topology.

You can refer to the following documentation for more information:

Simscape Electrical Documentation

Solar Cell - Photovoltaic solar cell - MATLAB