low
mid
high
Solar incidence angle
[°]
70
80
90
membership functions [-]
1
Figure 3: Fuzzy logic variable "theta" (incidence angle of the direct solar radiation on
the window)
The rule base, providing the blind position as a fuzzy variable, is given by the table
below.
Ehdiff low
High
Evdir low
mid
high
very
high
low mid high very
high
theta=low open
half
closed
closed closed half
closed
half
closed
closed closed
theta=mid open
half
open
half
closed
half
closed
half
closed
half
closed
half
closed
half
closed
theta=high
open open open open half
closed
half
closed
half
closed
half
closed
B. "User not present" strategy
The window, equipped with its blind, is considered as a "heat source" controllable by the
blind position. A simple thermal model for the window + blind system has been used in
the controller, giving the heat power per unit area of window by the following formula:
Ps = Gv
· g · + Gv · g · g · (1-) U'' · (Ti-Te)
where
= blind position (01, 0=closed, 1=open)
Gv = global vertical radiation
[W/m2]
g = transmission coefficient of window glazing
Summary :
Ehdiff low High Evdir low mid high very high low mid high very high theta=low open half closed closed closed half closed half closed closed closed theta=mid open half open half closed half closed half closed half closed half closed half closed theta=high open open open open half closed half closed half closed half closed B.
Tags :
open,high,blind,window,low,position,mid,angle,radiation,solar,fuzzy,ariable,ery