摘要 |
<p>A refrigeration system having a compressor, a condenser and an evaporator between the condenser and the compressor. A controllable valve unit at the input side of the evaporator has degrees of opening for controlling fluid flow through said evaporator. A control unit controls the degrees of opening of the valve unit. Sensors connected to the control unit and opposite ends of the evaporator detect superheat temperatures between the input and output sides of the evaporator. The control unit is operable to control the degrees of valve opening in accordance with the superheat temperatures (1) at a first greater desired opening and closing displacement rate between desired predetermined minimum and maximum values of a first range of superheat temperature values and (2) at a second opening and closing rate lesser than the first displacement rate for a second range of superheat temperature values lower than the first range of values. The second range of superheat temperature values lie within the region of 10% or less of the first range of superheat temperature values.</p> |