CN202851413U - Air cooling control device - Google Patents

Abstract

The utility model relates to an air-cooling control device, comprising: a temperature detection sensor, a plurality of fans, and a PLC module connected with the temperature detection sensor and suitable for controlling a corresponding number of fans to work according to the external temperature. This new model uses PLC module to replace the traditional relay circuit, which avoids the defects of cumbersome wiring and high relay failure rate; the number of fans is controlled according to the temperature, and the fan or a small number of fans can not be started in winter when the temperature is low, and the temperature is high In summer, it is necessary to start all the fans to dissipate heat, which saves a lot of electric energy and prolongs the life of the motor.

Description

An air-cooled control device

technical field

The utility model relates to an air cooling control device.

Background technique

In the prior art, transformers with a voltage level of 110kV and below often use a cooling fan to cool the transformer, and the working condition of the cooling fan directly affects the load carrying capacity of the transformer; and the air cooling system often fails. According to statistics, Air-cooling system failures are mainly divided into control circuit component failures, and the main reason for control circuit failures is that the control components use electromagnetic relays. These discrete components have low reliability, high failure rate, and poor anti-interference ability for a long time, resulting in These components are often burned and damaged, affecting the operation of the air-cooling system, so how to design a replacement electromagnetic relay to control the entire air-cooling system is a technical problem in this field.

Utility model content

The technical problem to be solved by the utility model is to provide an air cooling control device suitable for detecting the ambient temperature to control the number of fans activated.

In order to solve the above technical problems, the present invention provides an air-cooling control device, including: a temperature detection sensor, several fans, and a PLC module connected to the temperature detection sensor and suitable for controlling a corresponding number of fans according to the external temperature.

Furthermore, because the motor is an inductive load, it will increase the reactive power of the grid during use and reduce the power factor. Therefore, it is necessary to use chained SVG (static var generator, also known as Static synchronous compensator) control device to improve the power factor in the grid, so the air-cooled control device also includes: a chained SVG control device suitable for correcting power factor, the chained SVG control device is connected to the Input terminal for the three-phase power supply of the air-cooled control unit.

Compared with the existing technology, the new air-cooled control device has the following advantages: (1) The PLC module is used to replace the traditional relay circuit, which avoids the cumbersome wiring and the defects of high failure rate of the relay; (2) The fan is controlled according to the temperature. Quantity control, in the winter when the temperature is low, you can not start the fan or a small number of fans, and in the summer with high temperature, you need to start all the fans to dissipate heat, which saves a lot of power and prolongs the life of the motor; The above-mentioned chain-type SVG control device corrects the problem that the power factor of the power grid decreases due to the operation of the motor, and improves the utilization rate of the transformer. the

Description of drawings

In order to make the content of the new model easier to understand clearly, the new model will be further described in detail based on the specific embodiments below in conjunction with the accompanying drawings, wherein

Fig. 1 Structural block diagram of the new air-cooled control device;

Figure 2 is a structural block diagram of the new chained SVG control device.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the new model is described in detail:

As shown in FIG. 1 , an air-cooling control device includes: a temperature detection sensor, several fans, and a PLC module connected to the temperature detection sensor and adapted to control a corresponding number of fans according to the external temperature.

In the summer when the temperature is high, the heat of the transformer is huge, so when the temperature detected by the sensor reaches 60 degrees Celsius, all the fans work; in the winter with low temperature, because the ambient temperature is low, the heat of the transformer is not high In some cases, the fan can be turned on less or not.

As shown in FIG. 2 , the air-cooling control device further includes: a chain-type SVG control device suitable for correcting power factors, and the chain-type SVG control device is connected to the input end of the three-phase power supply of the air-cooling control device.

The chained SVG control device includes:

H-bridge multi-connected multi-level inverter, which is composed of three-phase H-bridge power modules connected to the three-phase power supply, wherein, at least one spare H-bridge unit circuit is added to each phase H-bridge power module ;

An automatic bypass circuit is set at the output end of each H-bridge unit circuit, and when an H-bridge unit circuit is damaged, the H-bridge unit circuit is bypassed;

A sampling circuit adapted to collect instantaneous values of voltage and current of the three-phase power supply;

； Separate phase current independent control circuit, which is connected to the sampling circuit and is suitable for calculating the modulation ratio M and phase of the sinusoidal modulation wave required by the pulse width modulation circuit according to the instantaneous value of the voltage and current of the three-phase power supply horn

;

对各H电桥单元电路之间采用的载波三角波移相SPWM进行控制；即，当损坏的H电桥单元电路旁路后，该脉宽调制电路适于在保持所述采样电路的采样周期不变的基础上，改变该损坏的H电桥单元电路所在的一相H桥功率模块的所述载波三角波移相SPWM的载波频率，以获得与该相H桥功率模块中剩余的H电桥单元电路数量相对应的载波三角波移相SPWM的脉冲调制波形。 A pulse width modulation circuit, connected to the phase-splitting current independent control circuit, used for adjusting the modulation ratio M and the phase angle according to the sinusoidal modulation wave

The carrier triangular wave phase-shifting SPWM adopted between each H bridge unit circuit is controlled; that is, after the damaged H bridge unit circuit is bypassed, the pulse width modulation circuit is suitable for keeping the sampling period of the sampling circuit constant. On the basis of the change, change the carrier frequency of the carrier triangular wave phase-shifting SPWM of the phase-shifted SPWM of the one-phase H-bridge power module where the damaged H-bridge unit circuit is located, so as to obtain a The pulse modulation waveform of the phase-shifted SPWM of the carrier triangular wave corresponding to the number of circuits.

Apparently, the foregoing embodiments are only examples for clearly illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And these obvious changes or changes derived from the spirit of the present invention are still within the scope of protection of the present invention.

Claims (2)

1. A kind of air cooling control device, it is characterized in that comprising: temperature detection sensor, some fan, the PLC module that is connected with described temperature detection sensor and is suitable for controlling the fan work of corresponding number according to the height of external temperature. 2. The air-cooling control device according to claim 1, further comprising: a chain-type SVG control device suitable for correcting power factor, the chain-type SVG control device being connected to the three-phase control device of the air-cooling control device The input terminal of the power supply.

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