1. About frequency conversion way

The intelligent air-cooled frequency conversion control system uses only fan frequency conversion, not the oil pump frequency conversion. The oil flow relay is used to test the operation condition of the oil pump. If the oil pump changes frequency, the oil flow state is unstable, easy to cause false alarm.

2. The control mode of a set of inverter is applied to each cooling loop.

The purpose of this method is to meet the requirements of the strong oil wind cooling control, and to ensure that the auxiliary and standby unit cooler is kept. In this way, if a group of cooler fails, it will not affect the operation of other coolers and directly repair or replace the fault cooler group.

3. Energy-saving effect

Choose intelligent air-cooled frequency conversion control system, power saving at least between 30% ~ 50%, according to conservative calculations, power saving 30%, equivalent to dispense into 1 set of cooler, with each group of cooler per hour 3 kw power consumption calculation, a year can save electricity: 3 × 24 × 365 = 26280 kw·H

4. Noise reduction index

The sound of fan running is one of the main sources of transformer noise. By measuring and comparing the transformer of 180MVA, under the same load and the same working condition, the smooth regulation speed and optimized operation of the variable frequency control wind cooler can be reduced to 20%~50% compared with the working frequency. The average noise index of transformer is greatly reduced, and the performance index of transformer is improved.

5. Intelligent implementation

The intelligent air-cooled control system is equipped with a single unit with only components. Can receive oil temperature, load current and other operation parameters from other manufacturers' intelligent components; The working status of the intelligent air cooling control system is controlled by means of communication, and the working status and fault information of the cooler are uploaded. Ensure that all uploaded information meets the IEC61850 requirements.

6. A description of security.

Safety guarantee of equipment operation: the transformer intelligent air cooling variable frequency control system adopts innovative dual-mode (automatic mode and manual mode) control, with automatic mode conversion function. The manual mode is the traditional relay control mode, and the automatic mode is energy-saving, frequency conversion and intelligent control mode. The normal operating equipment is operated by automatic mode. When there is a failure or emergency, the mode can be automatically converted to manual mode. Control mode transition conditions as follows: I, PLC failure: set the detection module, to test the work condition of the PLC, when there is a break or communications failure, control system from the automatic mode to manual mode; II, two groups of cooler failures: no matter the failure of fan motor, oil pump, oil flow relay fault or inverter, automatic operation of the system of above condition when the single failure, or a combination of two groups of cooler will be made by automatic mode to manual mode; III. Signal acquisition unit failure: when the signal acquisition unit is broken or communication failure occurs, the automatic mode can be transferred directly to manual mode.

Safety of component selection: low voltage electrical components of international famous brands. Siemens PLC, ABB inverter, contactor, relays and other low-voltage electrical components are selected from Siemens, Schneider, ABB, etc.