JPS644659B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement in an operating device for a transformer cooler that performs forced cooling.

[Background of the invention]

Generally, the power generated by a generator is supplied to the power system via a transformer, and the capacity of the generator is also increasing due to the increase in power demand and other reasons, and the transformer is also increasing accordingly. It is taking shape. These transformers are forced to be cooled to ensure sufficient cooling, but in the past there has been a tendency to cool them more than necessary, wasting power.
This will be explained with reference to FIG.

Figure 1 shows a conventional operating device for a transformer cooler, where 1 is a transformer, 2 is a load factor detection device such as a bushing current transformer, and 3 is a temperature sensor such as an oil temperature detector or winding temperature relay. The load factor detection device 2 and the temperature detection device 3 are respectively arranged in or around the transformer 1.
4 is a cooler control cubicle, 5 is a cooler group, 6
is an auxiliary machine consisting of an oil pump and a motor fan. The cooler control cubicle 4 includes a first stage current relay 7, a second stage current relay 8, a hard wire logic 9, and a magnetic switch 1.
0, 11, excitation coil 12 and disconnector 13, 1
It consists of 4. the load of the transformer 1 detected by the detection device 2 and the current relay currents 7 and 8;
Each detection value of the operating temperature of the transformer 1 detected by the temperature detection device 3 is transmitted to the hardwire logic 9, and the magnetic switch 10,
This method is carried out by changing the number of cooler units driven in the cooler group 5 through the cooler group 5.
It was controlled in a stepwise manner as shown by curve A in the figure. That is, the number of cooler units to be driven is increased or decreased at the number-of-drive switching point D on the curve A. Note that curve B is an ideal curve of required auxiliary power with respect to load factor. Therefore, since the cooling system of the cooler was roughly controlled, the cooling capacity was often excessive for the load factor of the transformer, and the solid shaded area in Figure 3 is excessive and uneconomical in terms of auxiliary equipment input. I was driving like crazy. Furthermore, since the auxiliary machines are controlled by super-moving and stopping at the number of drives D as the load factor changes, there is a drawback that bearings and the like in particular are susceptible to mechanical wear.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and provides a transformer that reduces excessive auxiliary input to the cooler and loss generated in the transformer body, enables energy saving, and prevents wear and tear on the bearings of the auxiliary equipment. The purpose of this invention is to provide an operating device for a portable cooler.

[Summary of the invention]

The operation device for a cooler for a transformer according to the present invention includes a detection device for detecting at least one of the temperature and load of the transformer, and is configured to control the operation of a motor of a group of coolers connected to the transformer. A converter that converts the data obtained by the detection device into an electrical signal, an analog input device that converts the output from the converter into an analog input signal, and a steady or unsteady load current of the transformer. In addition to correcting the time constant of the transformer, the control command is configured to memorize the temperature and load pattern based on the operating history of the transformer, and output signals for the air flow rate and oil flow rate appropriate for this temperature and load current. a data processing device that compares the analog input signal of the detection device with the signal from the control command device and compares and determines the control command to the motor of the cooler; and a data processing device that converts the signal from the data processing device into an analog output. It is provided with an analog output device for conversion and a speed control device for controlling the speed of the cooler motor based on the signal from the analog output device.

[Embodiments of the invention]

Hereinafter, an embodiment of the operating device for a transformer cooler according to the present invention will be described with reference to FIG. 2, in which the same parts as those in the prior art are denoted by the same reference numerals. 15 is a winding temperature or oil temperature detection device (for example, a resistance temperature detector) of the transformer 1; 16 is an ambient temperature detection device; 17 is a converter that converts the load factor detected by the load factor detection device 2 into an electrical signal; 18,
19 and 20 are temperature detection devices 3, 15, and 1, respectively.
This is a converter that converts the temperature detected by 6 into an electrical signal. The electrical signals output from these converters 17, 19, 20 enter an analog input device 21, and the electrical signals output from the converter 18 enter a control command device (for example, a sequence controller) 22.
to go into. This control command device 22 is equipped with a time constant that corrects fluctuations in the load current of the transformer 1 so that the sum of the auxiliary equipment loss and the loss generated in the transformer 1 body is minimized in response to the temperature and load current. It has built-in speed control data for auxiliary machines calculated in advance and has an auxiliary machine control function that issues control commands for the auxiliary machines based on this speed control data. The data processing device (for example, a microcomputer) 23 has built-in data 24 of allowable temperature for comparison, which is calculated in advance for operating conditions such as the load factor of the transformer 1 and the ambient temperature. It has a comparative judgment function of comparing the signal and the signal from the analog input device 21 with the built-in data 24. 25 is an analog output device, 26
is a speed control device consisting of a variable frequency inverter, etc.
Numerals 27 and 28 are magnetic switches for turning on and off the auxiliary power supply circuit, respectively, and 29 is a circuit breaker.

Normal operation of the cooler group 5 is performed by a command signal issued from the control command device 22 based on the load current of the transformer 1. If the load or ambient temperature of the transformer 1 suddenly changes to the extent that it differs significantly from the normal control command, the data processing device 23 compares and judges the signals from the detection devices 3, 15, and 16, and outputs the appropriate control command as an analog signal. An analog signal emanating from the analog output device 25 enters a speed control device 26 to control the cooler group 5.
The rotational speed of the auxiliary machine 6 can be appropriately controlled.

In this way, in the operating device for the transformer cooler of this embodiment, the auxiliary input to the cooler in response to load fluctuations of the transformer can be significantly reduced as shown in curve C shown in FIG. 3, and compared to the conventional curve A. As shown in the solid line and the dotted shaded area, the energy consumption is reduced by 20 to 30% compared to the above, making it possible to save energy and significantly reducing the loss in the transformer body. In addition, in the case of cooling capacity control, the rotation speed of the motor is controlled and the auxiliary equipment is not started or stopped, so the life of the auxiliary equipment can be extended because it is not subjected to impact forces acting on bearings and the like. In addition, when the speed of the auxiliary equipment is reduced, noise can be reduced, which is particularly noticeable when the load on the transformer is low, such as at night.

〔Effect of the invention〕

As described above, the operating device for a transformer cooler of the present invention has the effect of reducing excessive auxiliary equipment input to the cooler, making it possible to save energy, and preventing wear and tear on the bearings of the auxiliary equipment.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional transformer cooler operating device, FIG. 2 is a schematic diagram of an embodiment of the transformer cooler operating device of the present invention, and FIG. 3 is a load of the device shown in FIG. 2. FIG. 3 is a curve diagram of required auxiliary power in the case of speed control with respect to rate. 1...Transformer, 2...Load factor detection device, 3,1
5, 16...Temperature detection device, 4...Cooler control cubicle, 5...Cooler group, 6...Auxiliary equipment, 7,
8... Current relay, 9... Hard wire logic, 17, 18, 19, 20... Converter, 21
... Analog input device, 22 ... Control command device,
23...Data processing device, 24...Built-in data,
25...analog output device, 26...speed control device.

Claims (1)

[Claims] 1. In an operating device for a transformer cooler, the transformer cooler is equipped with a detection device that detects at least one of the temperature of the transformer and the load, and is configured to control the operation of a motor in a group of coolers connected to the transformer. , an ambient temperature detector that detects the ambient temperature of the transformer, and an auxiliary equipment control device that controls the auxiliary equipment based on the detection signal of the detection device and outputs the amount of oil and air that is adapted to the temperature and load. a storage device containing a transformer's permissible temperature value with respect to a pre-calculated transformer load factor and a transformer's ambient temperature; and a signal from either the detecting device or the ambient temperature detector. A control device for controlling the auxiliary equipment via the auxiliary equipment control device by comparing the change with an allowable temperature in the storage device.