Hi!
I'm trying to run a step by step simulation in energyplus using pyFMI with some input and output variables, using the EnergyplusToFMU export tool. In order to debug my code I added the variables below to check the datetimes in the simulation. I have set a time delta of 10 min for synchronization, both in the idf file and in the pyFMI model - 600 seconds.
EnergyManagementSystem:OutputVariable,
Current Time,
CurrentTime,
Averaged, ! Type of Data in Variable
ZoneTimeStep; ! Update Frequency
ExternalInterface:FunctionalMockupUnitExport:From:Variable,
EMS,
Current Time,
CurrentTime;
After calling initialize(), I see that the first value of CurrentTime is 0, which makes sense because it starts at midnight, but then the next timestep - after calling doStep() - I get that CurrentTime is 24.0 - the end of the day in one step? Then subsequent calls to doStep() return: 0.183333333, 0.35714285, 0.52380952 ... it looks like the 10 min delta is not respected. Meanwhile, if I check the model.time it does work as expected: initial time is 00:00, then it increases by 10 min on each call.
For reference, I'm using energyplus 8.9, and ran the FMU export as Co-Simulation v20. According to https://bigladdersoftware.com/epx/docs/8-9/ems-application-guide/variables.html#built-in-variables, I understand that the CurrentTime EMS variable should match the result from modulus(model.time, 24*3600) / 3600, that is, the seconds in a given day expressed as hours.
Is it possible that the variable is not reported correctly? Or is energyplus really doing those variable steps? I'm a bit confused about this. I also added logging for the direct normal radiation, month, day, hour and minute coming from energyplus and it seems like energyplus is really doing those steps - those variables seem to agree with the info from the weather file.
Thank you beforehand!
Update: It seems that not only the CurrentTime is wrong, this is a log of the model.time, Month, DayOfMonth, Hour, Minute (EMS variables), Diffuse Horizontal Radiation, and Direct Normal Radiation (regular Output variables), respectively, as reported by the model:
DEBUG:07-23 10:40:00 [7.]-[23.] [10.]:[31.42857143], diffuse: [330.66666667], direct: [276.83333333]
DEBUG:07-23 10:50:00 [7.]-[23.] [10.]:[41.11111111], diffuse: [322.33333333], direct: [316.66666667]
DEBUG:07-23 11:00:00 [7.]-[23.] [10.]:[51.], diffuse: [314.], direct: [356.5]
DEBUG:07-23 11:10:00 [7.]-[23.] [11.]:[1.], diffuse: [305.66666667], direct: [396.33333333]
DEBUG:07-23 11:20:00 [7.]-[23.] [11.]:[11.42857143], diffuse: [297.33333333], direct: [436.16666667]
DEBUG:07-23 11:30:00 [7.]-[23.] [11.]:[21.42857143], diffuse: [289.], direct: [476.]
DEBUG:07-23 11:40:00 [7.]-[23.] [11.]:[31.11111111], diffuse: [286.], direct: [495.33333333]
DEBUG:07-23 11:50:00 [7.]-[23.] [11.]:[41.11111111], diffuse: [283.], direct: [514.66666667]
DEBUG:07-23 12:00:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 12:10:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 12:20:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 12:30:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 12:40:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 12:50:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 13:00:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
DEBUG:07-23 13:10:00 [7.]-[23.] [11.]:[51.42857143], diffuse: [280.], direct: [534.]
From 12:00 on the model always yields the same results. Also, as already seen previously, the Hour and Minute don't match the expected model.time.
