Method for function monitoring and/or control of a cooling system, and a corresponding cooling system

1. A method for monitoring the function and the operational reliability of a cooling system having at least one thermosyphon, for transformers, the cooling system including at least one evaporator and at least one condenser, and using a coolant which can be vaporized in the at least one condenser and a gaseous medium, as a heat carrier in the at least one evaporator, the method comprising:

determining a heat exchanger effectiveness of the cooling system wherein a global effectiveness ε of the at least one thermosyphon is determined using the relationship

ɛ

=

(

T

env

-

T

condens

out

)

(

T

env

-

T

evap

in

)

or

ɛ

=

(

T

evap

in

-

T

evap

out

)

(

T

evap

in

-

T

env

)

which is a ratio of a difference between temperatures at a condenser inlet (T env ) and at a condenser outlet (T condens out ) to a difference between a temperatures at the condenser inlet (T env ) and at an evaporator inlet (T evap in ),

comparing the evaporator inlet temperature with plural temperature threshold values;

comparing the global effectiveness ε of the at least one thermosyphon with plural effectiveness threshold values; and

generating a warning signal when comparison results based on the plural temperature threshold values and comparison results based on the plural effectiveness threshold values are outside predetermined limits,

wherein temperature measurements are carried out one of sequentially to reduce a number of measurement channels used to record temperature characteristic values or at a same time.

2. The method according to claim 1 , wherein in the event of a disturbance, the flow of the gaseous heat carrier is interrupted at times to rectify the disturbance.

3. The method according to claim 1 , wherein in the event of a disturbance, the flow direction of the gaseous heat carrier is reversed at times to rectify the disturbance.

4. The method according to claim 1 , wherein the condenser and the evaporator are heated.

5. The method according to claim 1 , comprising:

comparing the global effectiveness of the at least one thermosyphon with a lower effectiveness threshold and an upper effectiveness threshold.

6. The method according to claim 5 , comprising:

comparing the evaporator inlet temperature with a first temperature threshold.

7. The method according to claim 6 , comprising:

determining that the cooling system is serviceable, if the global effectiveness of the at least one thermosyphon is within a range of the lower and upper effectiveness thresholds and the evaporator inlet temperature is within the first temperature threshold.

8. The method according to claim 7 , wherein when the global effectiveness is outside a range of the lower and upper effectiveness thresholds and the evaporator inlet temperature is outside the first temperature threshold, the method comprising:

comparing the evaporator inlet temperature with a second temperature threshold; and

generating a warning signal if the global effectiveness of the at least one thermosyphon is outside the range of the lower and upper effectiveness thresholds and the evaporator inlet temperature is outside the second temperature threshold.

9. The method according to claim 8 , comprising:

at least one of inspecting and repairing the cooling system if the evaporating inlet temperature is above the second temperature threshold.

10. The method according to claim 8 , comprising:

inspecting the cooling system if the global effectiveness of the at least one thermosyphon is above the upper effectiveness threshold; and

repairing the cooling system if the global effectiveness of the at least one thermosyphon is below the lower effectiveness threshold.