CONTROL APPARATUS FOR COOLING SYSTEM

摘要

A cooling system includes a cooling tower, a refrigeration device, a cooling fan provided in the cooling tower, a cooling water pump which circulates cooling water between the cooling tower and the refrigeration device, a temperature sensor which detects the cooling water temperature at an inlet or outlet of the cooling tower, and an inverter apparatus which variably controls the speed of the cooling tower. The output frequency of the inverter apparatus is gradually reduced after the output frequency reaches an upper limit frequency, a condition at which a temperature detection value of the cooling water does not rise despite the reduction in the output frequency is stored, and the inverter apparatus is operated thereafter on the basis of the stored condition.

主权项

1. A control apparatus for a cooling system having a cooling tower, a refrigeration device, a cooling fan provided in the cooling tower, and a cooling water pump configured to circulate cooling water between the cooling tower and the refrigeration device, the control apparatus comprising:
a temperature sensor configured to detect a temperature of the cooling water at a water passage that is an inlet or outlet of the cooling tower, to obtain a temperature detection value; an inverter apparatus configured to
calculate a command value usable to control the temperature of the cooling water such that the temperature detection value matches a preset value, andvariably control a speed of a cooling device that is the cooling fan or the cooling water pump by generating an AC voltage at an output frequency based on the command value; and a wet-bulb temperature estimation controller configured to
cause gradual reduction of the output frequency of the inverter apparatus when the output frequency has reached an upper limit frequency,store a value of the output frequency at which the temperature of the cooling water at the water passage does not rise despite the reduction of the output frequency, andcontrol the cooling device on the basis of the stored value of the output frequency.