초록 ▼

A portable auxiliary cooling system for cooling electrical power transformers is provided with an intelligent controller that is programmable for functioning in a plurality of different operational modes. A plurality of sensors monitor cooling system equipment operation, transformer top oil temperat

A portable auxiliary cooling system for cooling electrical power transformers is provided with an intelligent controller that is programmable for functioning in a plurality of different operational modes. A plurality of sensors monitor cooling system equipment operation, transformer top oil temperature and transformer current. The cooling system controller includes a user-interface panel, a modem and/or other digital communications circuitry, data storage memory and a computer or microprocessor that performs real-time heat removal rate computations and automatically controls heat pump and fan operation in response to the computed results. System performance data, sensor readings and alarm condition indications are indicated on a user-interface panel and may also be provided to a remote station or operator using conventional digital communication facilities.

대표청구항 ▼

1. In a cooling system for an electrical power transformer, said cooling system having at least a coolant pump, a heat exchanger unit, a plurality of current and temperature sensors for monitoring operation of cooling system, the transformer and ambient air temperature, and a programmable computer c

1. In a cooling system for an electrical power transformer, said cooling system having at least a coolant pump, a heat exchanger unit, a plurality of current and temperature sensors for monitoring operation of cooling system, the transformer and ambient air temperature, and a programmable computer controller comprising at least a CPU and a data storage memory, a method of automated control of cooling system operation, comprising the steps performed by the computer controller of:a) obtaining data from the plurality of sensors; b) computing a Measured Heat Removal rate (MHR) value for the cooling system based upon data obtained from at least one temperature sensor monitoring coolant temperature; c) computing a Calculated Heat Removal rate (CHR) value for the transformer based at least upon data obtained from sensors monitoring coolant temperature and ambient air temperature; d) computing a ratio value for MHR/CHR; and e) generating an alarm condition indication when the ratio value computed in (d) it is not within a predetermined range of values. 2. The method of claim 1 wherein steps (a) through (e) are repeated continuously.3. The method of claim 1 wherein the programmable computer controller of the cooling system includes a modem or other device for implementing digital communications and further includes the step of automatically providing an alarm condition indication to a remote receiving station in response to generating an alarm condition indication.4. In a cooling system for an electrical power transformer, said cooling system having a fluid coolant and a coolant pump, a heat exchanger unit, a heat exchanger fan, a plurality of sensors for monitoring operating conditions of the transformer and cooling system components, and an intelligent controller comprising a programmable computer, a method of implementing an automated control of cooling system operation, comprising the steps performed by the controller of:continually monitoring the plurality of sensors, said sensors providing at least temperature or electrical current consumption data to the computer controller; controlling a start-up of cooling system operation in response to a monitored sensor that provides data indicative of power transformer temperature, wherein a cooling operation is initiated whenever said data indicative of power transformer temperature is greater than a first predetermined temperature value stored in said programmable computer; controlling a shut-down of cooling system operation in response to a monitored sensor providing data indicative of the power transformer temperature, wherein a cooling operation is terminated whenever said data indicative of the power transformer temperature is less than a second predetermined temperature value stored in said programmable computer; and, wherein the controller computer further performs the steps of: a) obtaining data from the plurality of sensors; b) computing a Measured Heat Removal rate (MHR) value for the cooling system based upon data obtained from one or more the sensors; c) computing a Calculated Heat Removal rate (CHR) value for the transformer based at least upon data obtained from sensors monitoring coolant temperature and ambient air temperature; d) computing a ratio value for MHR/CHR; and e) generating an alarm condition indication when the ratio value computed in (d) it is not within a predetermined range of values. 5. The method of claim 4 wherein controlling the startup of cooling system operation comprises at least initiating a coolant pump operation.6. The method of claim 4 wherein controlling the startup of cooling system operation comprises at least initiating a heat exchanger fan operation.7. The method of claim 4 wherein controlling the shutdown of cooling system operation comprises at least terminating a coolant pump operation.8. The method of claim 4 wherein controlling the shutdown of cooling system operation comprises at least terminating a heat exchanger fan operation.9. The method of claim 4 wherein the controller computer further performs the step of periodically initiating operation of the heat exchanger fan and/or coolant pump during extended cooling system idle periods.10. An intelligent controller for a cooling system for cooling an electrical power transformer, said cooling system having at least a coolant pump, a heat exchanger unit, and a plurality of current and temperature sensors for monitoring operation of the cooling system and transformer, said controller comprising:a computer system including memory for program and data storage and a modem for providing digital communications capabilities with remote facilities, wherein said computer is programmed to: continually monitor the sensors and automatically control start-up and shut-down operations of the cooling system in response to sensor data indicative of one or more predetermined conditions; and, wherein the computer is further programmed to compute a value indicative of an actual heat removal rate provided by the cooling system during operation. 11. The cooling system controller of claim 10 wherein predetermined conditions for determining start-up and shut-down operations are received from a remote facility via the modem and stored in the computer system memory.12. The cooling system controller of claim 10 wherein a start-up operation comprises at least initiating coolant pump operation.13. The cooling system controller of claim 10 wherein a shut-down operation comprises at least terminating coolant pump operation.14. The cooling system controller of claim 10 wherein the computer is further programmed to initiate a periodic operation of at least said coolant pump during extended cooling system idle periods.15. The cooling system controller of claim 10 wherein the computer is further programmed to initiate a periodic operation of a heat exchanger fan during extended cooling system idle periods.16. The cooling system controller of claim 10 wherein a sensor for monitoring coolant temperature within the transformer continually provides the computer with coolant temperature data and wherein the computer is further programmed to automatically start cooling system operation whenever coolant temperature within the transformer increases to a predetermined setpoint value, said predetermined setpoint value being stored in said computer memory.17. The cooling system controller of claim 10 wherein the computer is further programmed to automatically start cooling system operation whenever specific predetermined anticipatory conditions exit, said predetermined anticipatory conditions being stored in said computer memory and comprising a particular set of current and/or temperature data values detected by said sensors.18. The cooling system controller of claim 17 wherein said predetermined anticipatory conditions comprise a predetermined ambient temperature value and a detected increase in transformer phase current of a predetermined percentage amount occurring during a predetermined period of time, said predetermined ambient temperature value and predetermined percentage amount of transformer phase current increase and said predetermined period of time being stored in said computer memory.19. The cooling system controller of claim 17 wherein said anticipatory conditions comprise a predetermined time-of-day.20. The cooling system controller of claim 10 wherein the computer is further programmed to compute a predicted heat removal rate and to provide a remote facility with an indication of a system performance alarm condition generated whenever a computed actual heat removal rate is outside of a preprogrammed tolerance range for said computed predicted heat removal rate.21. The cooling system controller of claim 10 wherein the computer is further programmed to provide both a local indication and an indication to a remote facility of said computed actual heat removal rate.22. The cooling system controller of claim 10 wherein the computer is further programmed to provide an indication to a remote facility of the transformer coolant temperature.23. The cooling system controller of claim 10 wherein the computer is further programmed to provide a warning indication to a remote facility of a high temperature condition existing for the transformer coolant when the coolant temperature is detected to be above a predetermined temperature.24. The cooling system controller of claim 10 wherein the computer is further programmed to provide an indication to a remote facility of a sensor failure.25. The cooling system controller of claim 10 wherein the computer is further programmed to periodically determine a health/accuracy of one or more sensors through a comparison of a plurality of sensor data readings acquired during cooling system operation and to provide an indication to a remote facility of said health/accuracy.26. The cooling system controller of claim 10 wherein the cooling system operates in a predetermined fail safe mode if the cooling system controller fails to operate properly and the computer is further programmed to provide an indication to a remote facility of said fail safe mode operation.27. The cooling system controller of claim 10 wherein the cooling system operates in a predetermined fail safe mode if a transformer heat load exceeds a predetermined cooling capacity of the auxiliary cooling system to provide an indication to a remote facility of operating in said fail safe mode operation.28. The cooling system controller of claim 10 wherein the computer is further programmed to store historical transformer performance data in the memory.29. A method for operating a cooling system for an electrical power transformer, said cooling system having an intelligent controller for providing real-time monitoring and control of cooling system performance and transformer operating condition, said controller comprising at least a programmable computer and data storage memory, comprising the steps performed by the computer of:computing a first value indicative of actual heat removal rate provided by the cooling system during operation; computing a second value indicative of predicted heat removal rate for the cooling system under design conditions for an existing coolant flow rate and ambient temperature condition; performing a real-time comparison of said first and second computed values to determine if the first value is within a predetermined tolerance range of the second value; and providing an alarm condition indication if said first value is not within said predetermined tolerance range of the second value. 30. The intelligent controller of claim 10 wherein the cooling system is a stand alone heat removal system that is compact and housed in a portable housing.31. The method of claim 29 wherein the cooling system is a stand alone heat removal system that is used as an auxiliary cooling system in conjunction with existing transformer cooling system.