[esp-r] Re: 4 stage heater

[Jon Hand]

Have you considered treating each stage as a separate component, each triggered by
slightly different on/off logic control.  Whether these would be in parallel or series would be
your choice.

And perhaps you do not need to represent the heater with the plant side.  There is an
ideal zone control which is a multi-sage heater (fixed increments), you could use that
with a geometrically simple zone acting as a mixing box instead of the plant heater component.

-Jon Hand
________________________________________
From: esp-r-bounces at lists.strath.ac.uk [esp-r-bounces at lists.strath.ac.uk] On Behalf Of Dimitrios Sfakianakis [dimitrios.sfakianakis at strath.ac.uk]
Sent: 08 March 2013 13:58
To: 'esp-r at lists.strath.ac.uk'
Subject: [esp-r]  4 stage heater

Dear list,

I am modelling an HVAC plant at a component level. The air handling unit includes a 4-stage heater, which can operate in one of these 4 stages: 20kW 40kW 60kW and 80kW. I have managed to control the heater with a PID controller however I have not found a way to force it to take only these 4 discrete values. Are there any techniques integrated in Esp-r in order to model/control such a component?

Kind regards,

-

Dimitrios Sfakianakis