The ‘Biomass boiler’ template consists of a biomass boiler combined with a storage tank and a basic control strategy.
...
The programmable controller controls the biomass boiler. It gives the setpoint to the external PI-controller for regulating controlling the 3-way valve on the setpoint return temperature. Internally it will enable or disable the biomass boiler and it will calculate the modulation based on the measured return temperature (see figure below).
...
Measured return temperature is lower than maximum return temperature.
Once the biomass boiler has been disabled the sequence to enable the biomass boiler shall be inhibited for 10 minutes -> check of if this timer has run out.
Number of starts within 24h is lower than 6.
Temperature in TES is lower than 70°C.
...
SetpointReturn = 70;
(= setpoint return temperature for biomass boiler in °C)ReturnX1 = 70;
(= return temperature at maximum modulation in °C)ReturnX2 = 75;
(= return temperature at minimum modulation in °C)MaxReturn = 80;
(= disabling return temperature for biomass boiler in °C)TimerValue = 600;
(= delay timer of 10 minutes after disabling biomass boiler)TimeReset = 8640;
(= counter reset after 24h or 86400 seconds)MaxStarts = 6;
(= number of allowed starts per 24h)
The biomass boiler is released enabled based on 4 conditions:
Measured return temperature is lower than maximum return temperature.
Once the biomass boiler has been disabled the sequence to enable the biomass boiler shall be inhibited for 10 minutes.
Number of starts in 24h is lower than 6.
Temperature in TES is lower than 70°C.
...
When using a thermal energy storage vessel, the user should lock the temperature regime of the biomass boiler, or else the software will calculate continue with the propagated power and return temperature from the installation. The locked temperature regime is visualised in the figure below.
...