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To whom it concerns,
I want to control the proportionate amount of water flow diversion into a heat pump bank. A single type 106 is responsible to activate the heat pump bank and keep the temperature at 17C +- 1C. However, the number of active heat pumps should be proportionate to the mass flow rate that is diverted by tempering valve control. The more mass flow diverted towards the heat pump, more heat pumps are activated by type 910. I want to know how to divert proportionate flowrate in a way that the minimum number of heat pumps are activated while the temperature at the supply pipeline would be within the range demanded by type 106. Does a tempering valve generates the data?
I would appreciate it if you could give me a hint and even let me know whether the approach is correct or not.
The tempering valve might give you the signal that you're looking for. It calculates the fraction of flow that needs to go through a source that is producing a known temperature in order that when that flow is mixed with the liquid that didn't go through the source then you get the desired temperature.
Another way you might approach this is that if you know the mass flow rate in your loop and you know the temperature that you want to get from the heat pumps then you can make an equation block to calculate the energy that the heat pumps need to add/remove. You can then divide that by the nominal capacity of each heat pump and determine how many heat pumps are needed. The actual capacity of the heat pumps will differ somewhat from the nominal capacity based on present conditions but provided you are using a variable speed compressor heat pump then they should be able to internally modulate to compensate for that.
It looks from the picture as though you are on the right track. Of course there is a lot that I'm not able to see from the picture so the best thing to do is to use an online plotter (Type65) to watch the mass flow rate, the outlet temperatures, and the control signals that are being sent around your system. Set up Type65 so that it generates one plot per week (or perhaps one plot per day - there is a parameter you can use to control this). Watching those variables as the simulation runs will very quickly show you whether the number of heat pumps and the flow rate to them is matching well.
david
