[ADAGAIN] Adaptation of controller gain
Function block ADAGAIN calculates the gain factor for the energy recovery sequence based on the difference between outside air and extract air. It can be used for temperature or humidity control.
ADAGAIN calculates the gain factor for the energy recovery sequence based on the difference between outside air and extract air. The calculation works for temperature and humidity.
ADAGAIN calculates the present difference between outside air [Oa] and extract air [Ex] and determines the gain factor [GainFac] by means of the following function:
Example
If the difference is smaller than the design difference [DNom], the gain factor [GainFac] is greater than 1.0. The gain factor may be max. equal to the defined limit value [FacMax]. The greater the difference, the smaller the gain factor.
Input | Description | Data type | Default value |
|---|---|---|---|
|
Oa | Outside air Measured value for temperature or humidity | Real | 0.0 |
|
Ex | Extract air Measured value for temperature or humidity | Real | 0.0 |
|
DNom | Nominal difference Nominal difference on designing control | Real | 20.0 |
|
FacMax | Maximum factor Limit value to which the output [GainFac] is limited | Real | 1.0 |
Output | Description | Data type | Default value |
|---|---|---|---|
|
GainFac | Gain factor Output for the ERC sequence controller [GainFac] | Real | 1.0 |
The efficiency of the energy recovery system largely depends on the temperature or humidity difference. The greater the difference between outside air and extract air, the greater the positioning efficiency of the energy recovery system.
ADAGAIN is used together with function block PID_CTR responsible for energy recovery control. During energy recovery commissioning, the gain factor [GainFac] of the ERC sequence is set in accordance with the existing conditions so that control is stable.
When designing the control parameters, the prevailing difference between outside and extract air is entered as the design difference [DNom]. If the ratio between outside air and extract air changes, the gain factor is compensated to ensure stable energy recovery control. The output [GainFac] is interconnected with the input of the same name on function block PID_CTR that is controlled by ERC.
You can either use this block for temperature or humidity control.