| 摘要 |
<p>PURPOSE:To enable the quantity of circulating refrigerant for cooling a power cable to be adjusted, according to the ripple of the load of the power cable, and enable a refrigerant circulating pump to be operated efficiently. CONSTITUTION:A refrigerant circulating pump 28 is driven by the frequency being controlled through an inverter 40 by a controller 38. The controller 38 controls an inverter 40 so that the outlet temperature may be an approximately fixed value not more than the set value, according to the values detected by an outlet temperature detector 36, which detects the cable outlet temperature of the refrigerant equivalent to the load current of a power cable 12, and an inlet temperature detector 34, which detects the cable inlet temperature of the refrigerant. The flow rate of the refrigerant circulating pump 28 decreases according to the decrease of the load current, and also, since the temperature of the refrigerant is approximately constant, the pressure never increases, so the waste of the power of the pump can be saved.</p> |
