CN113099695A - PLC frequency conversion temperature control system for box-in ventilation of converter transformer - Google Patents
PLC frequency conversion temperature control system for box-in ventilation of converter transformer Download PDFInfo
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- CN113099695A CN113099695A CN202110375984.1A CN202110375984A CN113099695A CN 113099695 A CN113099695 A CN 113099695A CN 202110375984 A CN202110375984 A CN 202110375984A CN 113099695 A CN113099695 A CN 113099695A
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- 238000006243 chemical reaction Methods 0.000 title claims abstract description 23
- 238000009423 ventilation Methods 0.000 title claims abstract description 17
- 239000007787 solid Substances 0.000 claims abstract description 6
- 230000008859 change Effects 0.000 claims abstract description 5
- 230000009467 reduction Effects 0.000 abstract description 7
- 238000004134 energy conservation Methods 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 11
- 238000009413 insulation Methods 0.000 description 8
- 230000017525 heat dissipation Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000012544 monitoring process Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000003584 silencer Effects 0.000 description 1
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/20—Modifications to facilitate cooling, ventilating, or heating
- H05K7/2089—Modifications to facilitate cooling, ventilating, or heating for power electronics, e.g. for inverters for controlling motor
- H05K7/20909—Forced ventilation, e.g. on heat dissipaters coupled to components
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/20—Modifications to facilitate cooling, ventilating, or heating
- H05K7/20009—Modifications to facilitate cooling, ventilating, or heating using a gaseous coolant in electronic enclosures
- H05K7/20209—Thermal management, e.g. fan control
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- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Power Engineering (AREA)
- Cooling Or The Like Of Electrical Apparatus (AREA)
Abstract
The invention provides a PLC frequency conversion temperature control system for box-in ventilation of a converter transformer, which comprises: the system comprises a PLC, a first temperature sensor, a second temperature sensor, a third temperature sensor, a signal multiplier, a variable frequency fan and a solid state relay; the output end of the first temperature sensor, the output end of the second temperature sensor and the output end of the third temperature sensor are respectively electrically connected with the input end of the signal multiplier, and the output end of the signal multiplier is electrically connected with the input end of the PLC; the signal multiplier is used for sending the amplified temperature analog signal to the PLC; the solid-state relay is used for adjusting the opening and the wind speed of the variable frequency fan according to the control signal of the PLC controller so as to adjust the temperature inside the box-in. The system can automatically adjust the rotating speed of the fan according to the change of the internal temperature of the box-in, thereby realizing energy conservation and noise reduction and providing guarantee for the safe and energy-saving operation of the transformer.
Description
Technical Field
The invention relates to the technical field of converter transformers, in particular to a PLC (programmable logic controller) variable-frequency temperature control system for box-in ventilation of a converter transformer.
Background
Converter transformers are one of the most important devices of a dc converter station and are a major noise source of the converter station. In the converter station transformer noise control technology, a box-in sound insulation structure seals a converter transformer body by utilizing a detachable sound insulation chamber with a ventilation and heat dissipation silencer, and a cooling fan of the converter transformer is placed outside the sound insulation chamber, so that the influence of the converter transformer on the inside and the surrounding environment is reduced.
The sound insulation effect of the box-in sound insulation structure is better than that of a sound barrier, and the box-in sound insulation structure is applied to domestic convertor stations. The purpose of reducing noise can be effectively achieved by using the noise reduction technology of the box-in structure, and the box-in structure is simple and easy to realize. The method has great significance for mastering the noise reduction technology of the box-in structure, improving the level and the strength of the direct current technology in China and enhancing the competitiveness of the converter transformer products.
However, in a large number of designs and actual construction processes, the heat dissipation of the transformer is not smooth after the box-in noise reduction equipment is additionally arranged, especially in summer and extreme weather. Therefore, the internal heat dissipation problem of the box-in sound insulation device can influence the normal operation of the converter transformer.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a PLC frequency conversion temperature control system for ventilation of a converter transformer box-in.
The invention provides a PLC frequency conversion temperature control system for ventilation of a converter transformer box-in, which comprises: the system comprises a PLC, a first temperature sensor, a second temperature sensor, a third temperature sensor, a signal multiplier, a variable frequency fan and a solid state relay; the first temperature sensor is arranged at an air inlet in the box-in, the second temperature sensor is arranged at the middle part in the box-in, and the third temperature sensor is arranged at an air outlet in the box-in; the output end of the first temperature sensor, the output end of the second temperature sensor and the output end of the third temperature sensor are respectively electrically connected with the input end of the signal multiplier, and the output end of the signal multiplier is electrically connected with the input end of the PLC; the signal multiplier is used for sending the amplified temperature analog signal to the PLC; the output end of the solid-state relay is electrically connected with the input end of the variable frequency fan, and the solid-state relay is used for adjusting the opening and the wind speed of the variable frequency fan according to the control signal of the PLC controller so as to adjust the temperature inside the box-in.
Optionally, the operating power supply of the signal multiplier is 24V.
Optionally, a signal output end of the PLC controller is electrically connected to an input end of the solid-state electrical relay, and the PLC controller transmits a control signal to the input end of the solid-state electrical relay so as to control the variable frequency fan through the solid-state electrical relay.
The embodiment can automatically adjust the rotating speed of the fan in real time through the box-in internal temperature, and really achieves energy conservation and high efficiency.
Optionally, the PLC controller is further configured to generate a control signal for adjusting the wind speed of the variable frequency fan in real time according to the temperature inside the box-in.
Optionally, the PLC controller includes: and the digital quantity input/output module and the analog quantity input/output module of the PLC are used for comparing and judging the internal temperature of the box-in and diagnosing faults so as to output corresponding control signals.
In this embodiment, the PLC controller is the core of the fan frequency conversion automation control. The control system mainly comprises a digital quantity input/output module and an analog quantity input/output module of the PLC, and mainly has the functions of temperature comparison and judgment, fault diagnosis, output control and the like. Meanwhile, information can be remotely transmitted, and centralized monitoring is facilitated.
Optionally, the PLC controller supports an in-situ control mode and a remote control mode.
In this embodiment, there are two modes in the PLC controller, local and remote. The requirements under different environmental conditions can be met, and real-time operation can be performed according to different requirements.
Optionally, when the internal temperature of the box-in is higher than or equal to the set temperature value, the PLC controller changes the operation mode of the variable frequency fan through an output electric signal of the internal circuit.
In this embodiment, the PLC controller has a function of setting a temperature. When the temperature detected by the temperature sensor is higher than or equal to the set temperature value, the PLC coding program can control the internal circuit to output an electric signal to change the mode of the variable-frequency fan.
Optionally, the PLC controller includes a fault indication window, and when a short-circuit fault of the line is detected, the short-circuit fault indicator of the fault indication window automatically lights up.
In this embodiment, the PLC controller is also provided with a function of indicating a failure. When the short-circuit fault occurs in the circuit, the short-circuit fault indicator senses the fault current, and a display window of the indicator is lightened, so that a user is reminded.
Optionally, the PLC controller comprises a programmer for performing a function extension to the PLC.
In this embodiment, the programmer is an indispensable device for PLC development and application, monitoring operation, and inspection and maintenance, and is used for programming, setting some settings for the system, and monitoring the PLC and the operating conditions of the system controlled by the PLC, but it does not directly participate in field control operation. Illustratively, small programmers PLC typically have hand-held programmers, and currently a computer (running programming software) typically serves as the programmer.
Compared with the prior art, the invention has the following beneficial effects:
the PLC frequency conversion temperature control system for ventilation of the converter transformer box-in can automatically adjust the rotating speed of a fan according to the change of the internal temperature of the box-in, thereby realizing energy conservation and noise reduction and providing guarantee for the normal operation of a transformer.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a schematic structural diagram of a converter transformer box-in ventilated PLC variable frequency temperature control system provided by the invention;
FIG. 2 is a schematic diagram of the internal connections of the first temperature sensor, the second temperature sensor, and the third temperature sensor of the present invention;
FIG. 3 is a schematic wiring diagram of the signal multiplier of the present invention;
FIG. 4 is a schematic structural diagram of a PLC of the S7-200 system;
FIG. 5 is a schematic wiring diagram of a PLC controller provided in an embodiment of the present invention;
fig. 6 is a simplified schematic diagram of a PLC hardware system.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.
Fig. 1 is a schematic structural diagram of a PLC variable frequency temperature control system for converter transformer box-in ventilation provided by the present invention, as shown in fig. 1, the system includes: PLC controller, three temperature sensor, signal multiplier, solid-state continuous electrical equipment, frequency conversion fan. Fig. 2 is a schematic diagram of internal wiring of the first temperature sensor, the second temperature sensor and the third temperature sensor in the present invention. As can be seen from fig. 1 and 2, the first temperature sensor is disposed at the air inlet in the box-in, the second temperature sensor is disposed at the middle portion of the inside of the box-in, and the third temperature sensor is disposed at the air outlet in the box-in. The output end of the first temperature sensor, the output end of the second temperature sensor and the output end of the third temperature sensor are respectively connected with the input end of the signal multiplier, the output end of the signal multiplier is connected with the input end of the PLC controller and used for inputting the amplified temperature analog signal into the PLC controller and transmitting the control signal to the input end of the solid-state relay, and the output end of the solid-state relay is connected with the input end of the variable frequency fan and used for adjusting the opening of the variable frequency fan and the wind speed to adjust the internal temperature of the box-in. The system can automatically adjust according to the change of the internal temperature of the box-in, thereby realizing energy conservation and noise reduction and providing guarantee for the normal operation of the transformer.
Fig. 3 is a schematic wiring diagram of the signal multiplier of the present invention, as shown in fig. 3, a first interface 1, a second interface 2, a third interface 3, a fourth interface 4, a fifth interface 5, and a sixth interface 6 of the signal multiplier respectively form input ends of a first analog signal, a second analog signal, and a third analog signal, a seventh interface 7, an eighth interface 8, a ninth interface 9, a tenth interface 10, an eleventh interface 11, and a twelfth interface 12 form an analog output end of a current signal, which is directly output to a PLC controller to control a switch and a wind speed of a fan, and a thirteenth interface 13 and a fourteenth interface 14 form a 24V power interface of the signal multiplier.
The signal output end of the PLC is connected with the input end of the solid-state relay and used for outputting 4-20mA (or 0-10V) analog quantity control signals to control the variable-frequency fan.
Illustratively, one signal output end of the PLC controller also outputs an analog quantity control signal of 4-20mA to control the rotating speed of the variable frequency fan, and the analog quantity control signal and the rotating speed of the variable frequency fan are in a negative phase relation. So, even if PLC controller trouble or outage do not have control signal input frequency conversion fan, when the electric current of inputing the frequency conversion fan is below 4mA, the frequency conversion fan can be with full speed power frequency operation, and when the input was 20mA, the frequency conversion fan can not operate to improve cooler operational reliability. That is to say, when the PLC controller breaks down, can let the frequency conversion fan all operate, the frequency conversion is with the highest rotational speed operation, possesses emergent ability, avoids because of PLC trouble compels converter transformer outage to improve direct current transmission system's operational reliability.
FIG. 5 is a schematic wiring diagram of a PLC controller provided in an embodiment of the present invention; fig. 6 is a simplified schematic diagram of a PLC hardware system. The embodiment of the invention provides a PLC frequency conversion temperature control system for box-in ventilation of a converter transformer, which solves the problems of poor heat dissipation of the transformer and internal heat dissipation of a box-in sound insulation device after a box-in noise reduction device is additionally arranged.
Those skilled in the art will appreciate that, in addition to implementing the system and its various devices provided by the present invention in purely computer readable program code means, the method steps can be fully programmed to implement the same functions by implementing the system and its various devices in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Therefore, the system and various devices thereof provided by the present invention can be regarded as a hardware component, and the devices included in the system and various devices thereof for realizing various functions can also be regarded as structures in the hardware component; means for performing the functions may also be regarded as structures within both software modules and hardware components for performing the methods.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.
Claims (9)
1. The utility model provides a PLC frequency conversion temperature control system that change of current transformer box-in ventilated which characterized in that includes: the system comprises a PLC, a first temperature sensor, a second temperature sensor, a third temperature sensor, a signal multiplier, a variable frequency fan and a solid state relay; the first temperature sensor is arranged at an air inlet in the box-in, the second temperature sensor is arranged at the middle part in the box-in, and the third temperature sensor is arranged at an air outlet in the box-in; the output end of the first temperature sensor, the output end of the second temperature sensor and the output end of the third temperature sensor are respectively electrically connected with the input end of the signal multiplier, and the output end of the signal multiplier is electrically connected with the input end of the PLC; the signal multiplier is used for sending the amplified temperature analog signal to the PLC; the output end of the solid-state relay is electrically connected with the input end of the variable frequency fan, and the solid-state relay is used for adjusting the opening and the wind speed of the variable frequency fan according to the control signal of the PLC controller so as to adjust the temperature inside the box-in.
2. The PLC variable frequency temperature control system of converter transformer box-in ventilation of claim 1, wherein the working power supply of the signal multiplier is 24V.
3. The converter transformer box-in ventilated PLC variable frequency temperature control system according to claim 1, wherein a signal output end of the PLC controller is electrically connected with an input end of the solid state relay, and the PLC controller transmits a control signal to the input end of the solid state relay so as to control the variable frequency fan through the solid state relay.
4. The PLC frequency conversion temperature control system for ventilation of the converter transformer box-in of claim 1, wherein the PLC controller is further configured to generate a control signal for adjusting the wind speed of the frequency conversion fan in real time according to the temperature inside the box-in.
5. The PLC frequency conversion temperature control system for ventilation of a converter transformer box-in according to any one of claims 1-4, wherein the PLC controller comprises: and the digital quantity input/output module and the analog quantity input/output module of the PLC are used for comparing and judging the internal temperature of the box-in and diagnosing faults so as to output corresponding control signals.
6. The PLC variable frequency temperature control system for converter transformer box-in ventilation according to any one of claims 1-4, wherein the PLC controller supports an on-site control mode and a remote control mode.
7. The PLC frequency conversion temperature control system for ventilation of the converter transformer box-in of any one of claims 1 to 4, wherein when the internal temperature of the box-in is higher than or equal to a set temperature value, the PLC controller changes the operation mode of the frequency conversion fan through an output electric signal of an internal circuit.
8. The PLC frequency conversion temperature control system for ventilation of a converter transformer box-in according to any one of claims 1-4, wherein the PLC comprises a fault indication window, and a short-circuit fault indicator of the fault indication window automatically lights when a short-circuit fault of a line is detected.
9. The PLC frequency conversion temperature control system for ventilation of a converter transformer box-in according to any one of claims 1-4, wherein the PLC controller comprises a programmer for performing functional expansion of the PLC.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110375984.1A CN113099695A (en) | 2021-04-07 | 2021-04-07 | PLC frequency conversion temperature control system for box-in ventilation of converter transformer |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110375984.1A CN113099695A (en) | 2021-04-07 | 2021-04-07 | PLC frequency conversion temperature control system for box-in ventilation of converter transformer |
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| CN202110375984.1A Pending CN113099695A (en) | 2021-04-07 | 2021-04-07 | PLC frequency conversion temperature control system for box-in ventilation of converter transformer |
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Application publication date: 20210709 |