JPS6259447B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an operating device for a transformer cooler that performs forced cooling.

Generally, power generated by a generator is supplied to the power grid via a transformer. The capacity of generators is also increasing due to increased demand for electric power and other reasons, and transformers are also becoming larger accordingly. This transformer is forcedly cooled by circulating oil cooled by a group of multiple coolers to ensure sufficient cooling, but conventional cooling methods result in more cooling than necessary. , there was a tendency for auxiliary power in the cooler group to be wasted.

This will be explained with reference to FIG. 1, which shows a conventional operating device for a transformer cooler.

The transformer 1 to be cooled or its surroundings is equipped with a standard condition detection device 2 equipped with a temperature detection device such as an oil temperature detector or a winding temperature relay, or a load factor detection device such as a bushing current transformer. It is placed. 3 is a cooler control cubicle which is a control component, and 4 is a cooler group. The detected values of the temperature and load of the transformer 1 detected by the detection device 2 are transmitted to the cooler control cubicle 3 which is the control part.
This is a method in which the number of units of cooler group 4 driven is changed to a predetermined number.The curve A in Fig. 3 shows the load factor on the horizontal axis and the required auxiliary power % on the vertical axis. It was controlled on a stage like this. That is, the number of cooler groups to be driven is increased or decreased at the drive number switching point D of the curve A. Note that curve B is an ideal curve of required auxiliary power with respect to load factor. Therefore, because the cooling capacity of the cooler was roughly controlled, the cooling capacity was often excessive for the load factor of the transformer, and the solid diagonal lines in Figure 3 indicate excessive and uneconomical input from auxiliary equipment. It was hot from driving. Furthermore, since the auxiliary machines are controlled by being started and stopped at the drive number switching point D as the load factor fluctuates, there is a drawback that the bearings and the like are susceptible to mechanical wear. The present invention was made in view of the above-mentioned circumstances, and provides an operating device for a transformer cooler that can save energy by reducing excessive auxiliary input to the cooler and prevent wear and tear on the bearings of the auxiliary equipment. It is intended to provide.

The operating device for a transformer cooler of the present invention includes a detection device that detects at least one of the temperature and load of the transformer, and a control section that processes data detected by the detection device. When configured to control the operation of the motors of connected cooler groups, the transformer receives and processes the data obtained by the sensing device, and adjusts the oil flow and delivery in accordance with this temperature and load. A data processing device configured to output an air volume signal, an appropriate speed command device for controlling the rotational speed of a motor that receives output from this data processing device, and cooling from any number of driven units according to instructions from this device. A speed control device configured to steplessly control the operation of each motor in the motor group is provided.

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 of the prior art are designated by the same reference numerals. 5 is a data processing device (for example, a microcomputer), and this data processing device 5
Built-in are a comparison basic data storage section 6 in which allowable temperature values for operating conditions such as the load factor of the transformer 1 and ambient temperature are stored in advance, a required cooling capacity calculation program 7, and a motor speed calculation program 8. ing. Reference numeral 9 indicates an appropriate speed command device for the auxiliary equipment of the cooler group 4, 10 indicates a speed control device including a variable frequency inverter or a resistance control device, 11 indicates an oil feed pump, and 12 indicates a motor fan.

The temperature or load factor of the transformer 1 detected by the detection device 2 is input into the data processing device 5 . Then, in the required cooling capacity calculation program 7 in this data processing device 5,
The required cooling capacity of the cooler group 4 is calculated based on the detection value of the detection device 2 and the comparison basic data of the allowable temperature value for the operating conditions of the transformer 1 stored in advance in the comparison basic data stock section 6. Based on the calculation results of the required cooling capacity here,
Auxiliary equipment (oil pump 11, motor fan 1
2) Calculation of the required speed is performed by the motor speed calculation program 8, and the calculation result is sent to the appropriate speed command device 9.
to communicate. According to the command from the appropriate speed command device 9,
The variable frequency inverter (not shown) of the speed control device 10 decelerates the motor to the speed calculated by the motor speed calculation program 8, and thereby the cooler group 4
Drive control of the oil feed pump 11 and motor fan 12 is performed steplessly. That is, control is performed to steplessly reduce the rotational speed of each motor of the oil feed pump 11 and the motor fan 12 as the load factor decreases from a state where the load factor is 100%. Then, power is supplied through speed control as shown in curve C shown in FIG. 3, and as compared to the conventional curve A, the auxiliary power in the diagonally shaded portions shown by the solid and dotted lines can be reduced.

In this way, the operating device for the transformer cooler of this embodiment can significantly reduce the auxiliary input to the cooler in response to transformer load fluctuations, as shown in Figure 3, by 20 to 30% compared to the conventional method. This reduces energy consumption, making it possible to save energy. In addition, in the case of cooling capacity control,
Since the number of revolutions of the motor is controlled steplessly and continuously, and the auxiliary equipment is not started or stopped, the life of the auxiliary equipment can be extended because it is not subject to impact forces acting on bearings, etc. Furthermore, reducing the speed of the auxiliary equipment can reduce noise, which is particularly effective when the load on the transformer is low, such as at night.

In the above embodiment, the rotation speed is gradually adjusted steplessly as the load decreases from 100%, but the starting point of this speed reduction is set to 75% or 50%, etc. It is also possible to start from the switching point D of an arbitrary number of driven units and perform stepless control. In this way, if the starting point of stepless adjustment of the rotational speed is set lower than the 100% load position, the capacity of the speed control device 10 can be reduced, which is economical, and the same It has an effect.

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, saving 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 relationship diagram of required supplementary electromotive force in the case of speed control with respect to rate. 1... Transformer, 2... Detection device, 4... Cooler group, 5... Data processing device, 6... Basic data storage section for comparison, 7... Required cooling capacity calculation program, 8... Motor Speed calculation program, 9...
Appropriate speed command device, 10...Speed control device, 11
...Oil pump, 12...Fan motor, D...
Switching point for the number of drive units.

Claims (1)

[Claims] 1. A cooler group consisting of a plurality of coolers each having a motor fan and an oil pump installed in a transformer to cool oil, and at least one of the temperature and load of the transformer. A device comprising a detection device for detecting and a control section for processing data detected by the detection device, and configured so that the control section controls the operation of each motor of the group of coolers connected to the transformer, The transformer includes a data processing device configured to input and process the data obtained by the detection device and output signals of the amount of oil and air blown that are adapted to the temperature and load, and An appropriate speed command device for controlling the rotational speed of the motor that receives the output from the processing device, and the operation of each motor of the cooler group is controlled steplessly from any number of drive units based on the commands from the appropriate speed command device. 1. An operating device for a transformer cooler, characterized in that it is provided with a speed control device formed in a. 2. The operating device for a transformer cooler according to claim 1, wherein the data processing device includes a comparison basic data storage section, a required cooling capacity calculation program, and a motor speed calculation program for required cooling performance.