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Hello everyone,
I have been reading materials in search of a way to control the discharge of battery. In a few words, the system configuration that I am simulating includes a solar panel (type 103b) connected to the inverter (type 48b) and a battery (type 47a). The the electricity produced, stored, and imported from the grid is used to meet the electricity demand, which includes the electricity for the operation of a heat pump.
For some comparison that I am trying to accomplish, I wanted to control the discharge of the battery only when the heat pump is turned on to simulate that the entire stored electricity is used for the heat pump operation, plus additional electricity needed to run it. From my mind arose different possibilities:
1 - through equation - create a signal on_off with output#2 of the battery (fractional state of charge) and multiplying it by the heat pump signal and then connecting it to input #3 (battery fractional state of charge) of the inverter. I have attempted this option but it failed. In fact it operates just the normal setup.
2 - through inverter type 48d, trying to use the input # 11/12 start/stop charging, but it does not have a control for discharging, so this would not have much sense.
3 - this third option, the easiest way, would be to change the current configuration making the PV-INV-BATT entirely to meet the heat pump demand only, however, that would deviate much from my research objective and from the results I already have would mean much more electricity dumped.
Do you think it is possible to control the discharge of a battery? Could you please comment on my thoughts and give some suggestion of how to proceed? Any literature available is much appreciated. Thank you in advance.
Regards
Humberto
@humbertosantos Humberto, I am sure that I am missing some nuances of what you are trying to do but if you use an equation to add the heat pump's power requirement to the load that is being passed to the inverter/charge controller input then when the heat pump requires power the inverter will know it and use first direct power from the PV if any is available, then power from the battery, then grid power if additional is needed. I would use Type48 in mode 1. If you have the v18 TESS Libs then there is an example in \Tess Models\Electrical\ called ResidentialPVwithLi-ionBattery.tpf. It does not have an intermittent load from an electrical device like what you are trying to do but it might give some ideas none the less. If it does not or if I am misunderstanding the problem, please feel free to reach out to our tech support hotline.
~david
