Bus voltage and temperature and humidity detection method for explosion-proof frequency converter

Abstract

The invention discloses a bus voltage and temperature and humidity detection method for an explosion-proof frequency converter, and relates to the technical field of frequency converter detection, and the system comprises a power supply circuit, a temperature and humidity sensor module, a bus voltage acquisition unit, an STC15 single-chip microcomputer, a data display unit and a DO function output unit. The power supply circuit supplies external voltage to the main control circuit and charges the standby power supply energy storage element at the same time; the temperature and humidity sensor module uploads environmental parameters in the cavity of the frequency converter in real time through a digital communication interface, and meanwhile, the bus voltage acquisition circuit inputs a signal to the STC15 single chip microcomputer; the STC15 single-chip microcomputer carries out digital processing and operation on the received temperature and humidity digital signals and the bus voltage analog signals, and drives the data display module to dynamically display bus voltage, temperature and humidity values in a cyclic polling mode; the STC15 single chip microcomputer triggers DO function output according to the real-time humidity data and preset logic grading; when the main power supply is powered off, the standby power supply automatically switches a power supply path to maintain continuous operation of the STC15 single-chip microcomputer.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of frequency converter detection, and particularly relates to a bus voltage and temperature and humidity detection method for an explosion-proof frequency converter. BACKGROUND

[0002] The explosion-proof frequency converter can produce a breathing phenomenon when operating and not operating in a well; this phenomenon can cause air containing moisture from the outside to enter the equipment, and the moisture can condense into water droplets at a low-temperature part in the equipment, thereby affecting the insulation performance of the equipment, increasing the risk of electrical faults such as short circuit and electric leakage of the equipment, and the direct-current bus voltage on the capacitor in the rectification circuit of the explosion-proof frequency converter of each manufacturer on the market cannot be directly displayed, which brings many inconveniences to on-site maintenance.

[0003] The explosion-proof frequency converters produced by different manufacturers on the market still use mechanical temperature and humidity controllers, which have low precision, cannot display the temperature and humidity information in the frequency converter in real time, and more importantly, the control is discontinuous, the equipment cannot be protected in time, the equipment can explode, and the bus voltage of the explosion-proof frequency converter of some manufacturers is indicated by different light-emitting diodes, which is neither intuitive nor accurate. SUMMARY

[0004] To solve the above technical problems, the application is implemented by the following technical scheme: The application is a bus voltage and temperature and humidity detection method for an explosion-proof frequency converter, which comprises a power supply circuit, a temperature and humidity sensor module, a bus voltage acquisition, an STC15 single-chip microcomputer, data display and DO function output. The specific steps of the method are as follows: Step S1: The power supply circuit converts the external input alternating voltage into a direct-current working voltage, supplies power to the main control circuit and charges the energy storage element of the standby power supply at the same time; Step S2: The temperature and humidity sensor module uploads the environmental parameters in the cavity of the frequency converter in real time through a digital communication interface, and the bus voltage acquisition circuit converts the high-voltage bus signal into a low-voltage sampling signal through a resistance dividing network and inputs the signal into the STC15 single-chip microcomputer; Step S3: The STC15 single-chip microcomputer performs digital processing and operation on the received temperature and humidity digital signals and bus voltage analog signals, and drives the data display module to dynamically display the bus voltage, temperature and humidity values in a cyclic polling mode; Step S4: The STC15 single-chip microcomputer triggers the DO function output according to the real-time humidity data according to a preset logic, and performs anti-condensation protection by controlling the start and stop of the dehumidifier and the on-off of the power supply of the frequency converter; Step S5: When the main power supply is powered off, the standby power supply automatically switches the power supply path to maintain the continuous operation of the STC15 single-chip microcomputer, and ensures that the bus voltage and temperature and humidity data acquisition are not interrupted.

[0005] Further, the power supply circuit input end is connected with an AC power supply, the output end supplies power to the STC15 single-chip microcomputer through the first diode, and charges the standby power supply through the second diode, the bus voltage acquisition input end is connected with the frequency converter bus terminal, the output end is connected with the analog port of the STC15 single-chip microcomputer, the temperature and humidity sensor module is connected with the STC15 single-chip microcomputer through a serial communication interface, and the output end of the STC15 single-chip microcomputer is connected with the data display module and the DO function output module respectively. The power supply circuit is used for providing power supply for the frequency converter. The bus voltage acquisition is used for collecting the frequency converter capacitor DC bus voltage. The temperature and humidity acquisition module is used for collecting the temperature and humidity inside the frequency converter cavity, and the temperature and humidity inside the frequency converter cavity are detected in real time, the collected information is communicated with the single-chip microcomputer through the 485 communication mode, the CPU in the STC15 single-chip microcomputer processes, and the temperature value and the humidity value are displayed in real time by using the nixie tube, when the humidity reaches the protection value, the dehumidifier is driven to work. The STC15 single-chip microcomputer is used for processing the collected bus voltage and temperature and humidity data, and driving the nixie tube display and the DO port action. The data display circuit is used for displaying data by using the nixie tube. The DO function output is used for driving the dehumidifier to work.

[0006] Further, the step S4 comprises the following steps: Step S41, when the humidity inside the frequency converter reaches above the first threshold value, the DO function outputs DO1 and DO2 of the frequency converter act, the dehumidifier 1 and the dehumidifier 2 start to work and dehumidify, the DO3 action disconnects the frequency converter control power supply, and the frequency converter is not allowed to work and run; Step S42, when the humidity inside the frequency converter is reduced to between the first threshold value and the second threshold value, only the DO function output DO1 acts, the dehumidifier 1 continues to dehumidify inside the frequency converter, and the DO function outputs DO2 and DO3 are not output, and the frequency converter can run; Step S43, when the humidity inside the frequency converter is reduced to below the second threshold value, the DO function outputs DO function are not output, the humidity inside the frequency converter is good, and all the DO function outputs are turned off.

[0007] A kind of bus voltage and humidity detection method for explosion-proof frequency converter, the specific device for realizing the method is: when the frequency converter is normally powered, input AC220V is connected to the J2 terminal of the frequency converter, passes through AC-DC power module U6, output power VCC1, one way is provided with power supply for single-chip microcomputer through diode D3, one way is charged through diode D5, resistance R16 backup power supply.

[0008] Further, when the frequency converter is normally powered, VCC voltage is greater than the voltage on the super capacitor, diode D4 bears reverse voltage and does not conduct, and the backup power supply does not work;When the frequency converter is powered off, the backup power supply starts to work, and the voltage on the super capacitor supplies power to the single-chip microcomputer through diode D4, so that the bus voltage, temperature and humidity of the frequency converter can be detected after the frequency converter is powered off.

[0009] Further, the bus voltage of the frequency converter is detected, and is connected to J3 terminal for sampling processing by resistance voltage division, and the single-chip microcomputer detects the voltage on the sampling resistor R12 and performs operation processing.

[0010] Further, the temperature and humidity sensor module is U3, which collects the temperature and humidity information inside the frequency converter cavity and uploads it to the single-chip microcomputer CPU for processing by communication mode.

[0011] Further, the single-chip microcomputer is U2, which processes and operates the collected DC voltage signal and temperature and humidity signal, drives the nixie tube to poll and display the bus voltage, current temperature and current humidity parameters, and drives DO output when the humidity is too large to control the dehumidifier.

[0012] Further, the nixie tube circuit is SEG1, which is used to display the bus voltage, current temperature and current humidity parameters of the frequency converter.

[0013] Further, the DO function output is J4, which detects the humidity when protection is reached, drives DO output, and controls the dehumidifier to act, prevents the humidity in the cavity from being too large to cause condensation phenomenon and thus causes the machine to explode.

[0014] The present application has the following advantages: 1、The successful application of the present application on the frequency converter enables the bus voltage, temperature and humidity data of the frequency converter to be observed very conveniently;When the frequency converter is operated for a long time, condensation phenomenon occurs, or the explosion-proof surface of the frequency converter is not maintained properly, causing moisture to enter the cavity, the cavity can be quickly heated to eliminate moisture, and the operation reliability of the explosion-proof frequency converter is improved.

[0015] Of course, any product implementing the present application does not necessarily need to achieve all the advantages described above at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the following embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0017] Figure 1 A flowchart of the bus voltage and temperature and humidity detection method for the explosion-proof frequency converter of the present application is shown. Figure 2 A module block diagram of the bus voltage and temperature and humidity detection method for the explosion-proof frequency converter of the present application is shown. Figure 3 A DO function output module schematic diagram of the bus voltage and temperature and humidity detection method for the explosion-proof frequency converter of the present application is shown. Figure 4 A power supply circuit module circuit schematic diagram of the bus voltage and temperature and humidity detection method for the explosion-proof frequency converter of the present application is shown. Figure 5 A total circuit schematic diagram of the bus voltage and temperature and humidity detection method for the explosion-proof frequency converter of the present application is shown. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0019] Please refer to Figure 1 The present application is a bus voltage and temperature and humidity detection method for an explosion-proof frequency converter, which comprises a power supply circuit, a temperature and humidity sensor module, a bus voltage acquisition, an STC15 single-chip microcomputer, data display and DO function output. The specific steps of the method are as follows: Step S1: The power supply circuit converts the external input AC voltage into a DC working voltage, supplies power to the main control circuit and simultaneously charges the energy storage element of the backup power supply; Step S2: The temperature and humidity sensor module uploads the environmental parameters in the frequency converter cavity in real time through a digital communication interface, and at the same time, the bus voltage acquisition circuit converts the high-voltage bus signal into a low-voltage sampling signal through a resistance dividing network and inputs it to the STC15 single-chip microcomputer. Step S3: The STC15 single-chip microcomputer processes and calculates the received temperature and humidity digital signals and bus voltage analog signals, and drives the data display module to dynamically display the bus voltage, temperature and humidity values in a cyclic polling manner; Step S4: The STC15 single-chip microcomputer triggers the DO function output according to the real-time humidity data according to a preset logic, and performs condensation protection by controlling the start and stop of the dehumidifier and the on-off of the frequency converter power supply; Step S5: When the main power supply is powered off, the standby power supply automatically switches the power supply path to maintain the continuous operation of the STC15 single-chip microcomputer, ensuring uninterrupted collection of bus voltage and temperature and humidity data.

[0020] The power supply circuit input end is connected to an alternating current power supply, the output end supplies power to the STC15 single-chip microcomputer through the first diode, and charges the standby power supply through the second diode, the bus voltage collection input end is connected to the frequency converter bus terminal, the output end is connected to the analog port of the STC15 single-chip microcomputer, the temperature and humidity sensor module is connected to the STC15 single-chip microcomputer through a serial communication interface, and the output end of the STC15 single-chip microcomputer is connected to the data display module and the DO function output module respectively; The power supply circuit is used to provide power for the frequency converter; The bus voltage collection is used to collect the frequency converter capacitor DC bus voltage detection; The temperature and humidity collection module is used to collect the temperature and humidity inside the frequency converter cavity, and to detect the temperature and humidity inside the frequency converter box in real time. The temperature and humidity detection module communicates the collected information to the single-chip microcomputer through the 485 communication mode, and the internal CPU of the STC15 single-chip microcomputer processes it. At the same time, a digital tube is used to display the temperature and humidity values in real time. When the humidity reaches the protection value, the dehumidifier is driven to work; The STC15 single-chip microcomputer is used to process and calculate the collected bus voltage and temperature and humidity data, and to drive the digital tube display and DO port action; The data display circuit is used to display data using a digital tube; The DO function output is used to drive the dehumidifier to work.

[0021] Step S4 includes the following steps: Step S41: When the internal humidity of the frequency converter reaches above the first threshold value, the DO function outputs DO1 and DO2 of the frequency converter act, driving the dehumidifiers 1 and 2 to start working to dehumidify, and DO3 act to disconnect the frequency converter control power supply, not allowing the frequency converter to work and run; Step S42: When the internal humidity of the frequency converter decreases to between the first threshold value and the second threshold value, only the DO function output DO1 acts, driving the dehumidifier 1 to continue to dehumidify the inside of the frequency converter, and the DO function outputs DO2 and DO3 do not output, and the frequency converter can run; Step S43, when the frequency converter internal humidity is reduced to below the second threshold, the DO function output is not output, the frequency converter internal humidity is good, all DO function outputs are closed.

[0022] One specific application of the embodiment is: When the frequency converter is normally powered on, the input AC220V is connected to the J2 terminal of the frequency converter, and the output power VCC1 is connected to the AC-DC power module U6. One way is to provide power to the single-chip microcomputer through diode D3, and the other way is to charge the standby power supply through diode D5 and resistor R16.

[0023] When the frequency converter is normally powered on, the VCC voltage is greater than the voltage on the super capacitor, and the diode D4 bears the reverse voltage and does not conduct, so the standby power supply does not work. When the frequency converter is powered off, the standby power supply starts to work, and the voltage on the super capacitor supplies power to the single-chip microcomputer through diode D4, so that the frequency converter can still detect the bus voltage, temperature and humidity after power failure.

[0024] The bus voltage detection of the frequency converter is connected to the J3 terminal through resistance sampling, and the single-chip microcomputer detects the voltage on the sampling resistor R12 and performs operation processing.

[0025] The temperature and humidity sensor module is U3, which collects the temperature and humidity information in the cavity of the frequency converter and uploads it to the single-chip microcomputer CPU for processing through communication.

[0026] The single-chip microcomputer is U2, which processes and operates the collected DC voltage signal and temperature and humidity signal, drives the nixie tube to poll and display the bus voltage, current temperature and current humidity parameters, and drives the DO output when the humidity is too large to control the dehumidifier.

[0027] The nixie tube circuit is SEG1, which is used to display the bus voltage, current temperature and current humidity parameters of the frequency converter.

[0028] The DO function output is J4, which detects the humidity when the protection is reached, drives the DO output, and controls the dehumidifier to act to prevent the cavity humidity from being too large to cause condensation phenomenon and cause the machine to explode.

[0029] In the description of the present specification, the description of the terms "one embodiment", "example", "specific example" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0030] The preferred embodiments of the application disclosed above are only to facilitate the elucidation of the application. The preferred embodiments do not describe all the details of the application and limit the application to the specific embodiments described. Obviously, many modifications and variations can be made in light of the teachings above. The description is chosen and described in order to best explain the principles of the application and its practical application to thereby enable others skilled in the art to best utilize the application and get the best results from the application. The application is only limited by the claims and their full scope and equivalents.

Claims

1. A method for detecting bus voltage and temperature / humidity in an explosion-proof frequency converter, characterized in that: Includes power supply circuit, temperature and humidity sensor module, bus voltage acquisition, STC15 microcontroller, data display and DO function output; The specific steps of the method are as follows: Step S1: The power supply circuit converts the externally input AC voltage into DC operating voltage to power the main control circuit and simultaneously charge the backup power storage element. Step S2: The temperature and humidity sensor module uploads the environmental parameters inside the inverter cavity in real time through the digital communication interface. At the same time, the bus voltage acquisition circuit converts the high-voltage bus signal into a low-voltage sampling signal through a resistor voltage divider network and inputs it to the STC15 microcontroller. Step S3: The STC15 microcontroller performs digital processing and calculation on the received temperature and humidity digital signals and bus voltage analog signals, and drives the data display module to dynamically display the bus voltage, temperature and humidity values ​​in a cyclic polling manner. Step S4: The STC15 microcontroller triggers the DO function output according to the preset logic levels based on the real-time humidity data, and performs anti-condensation protection by controlling the start and stop of the dehumidifier and the power supply of the frequency converter. Step S5: When the main power supply fails, the backup power supply automatically switches the power supply path to maintain the continuous operation of the STC15 microcontroller and ensure that the acquisition of bus voltage and temperature and humidity data is uninterrupted.

2. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The power circuit input terminal is connected to an AC power source, and the output terminal supplies power to the STC15 microcontroller via a first diode and charges the backup power source via a second diode. The bus voltage acquisition input terminal is connected to the inverter bus terminal, and the output terminal is connected to the analog port of the STC15 microcontroller. The temperature and humidity sensor module is connected to the STC15 microcontroller via a serial communication interface. The output terminals of the STC15 microcontroller are respectively connected to the data display module and the DO function output module. The power supply circuit is used to provide power to the frequency converter; The bus voltage acquisition is used by the acquisition circuit to detect the DC bus voltage of the inverter capacitor; The temperature and humidity acquisition module is used to collect the temperature and humidity inside the inverter cavity and to detect the temperature and humidity inside the inverter enclosure in real time. The temperature and humidity detection module communicates the collected information with the microcontroller via 485 communication. The CPU inside the STC15 microcontroller processes the information and displays the temperature and humidity values ​​in real time using a digital tube. When the humidity reaches the protection value, the dehumidifier is driven to work. The STC15 microcontroller is used to process the collected bus voltage and temperature and humidity data, and to drive the digital tube display and DO port operation. The data display circuit is used to display data using a digital tube; The DO function output is used to drive the dehumidifier to work.

3. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, Step S4 includes the following steps: Step S41: When the internal humidity of the frequency converter reaches or exceeds the first threshold, the DO function outputs DO1 and DO2 of the frequency converter are activated, driving dehumidifier 1 and dehumidifier 2 to start working and dehumidifying. DO3 is activated to disconnect the control power of the frequency converter, preventing the frequency converter from working. Step S42: When the humidity inside the inverter drops to between the first threshold and the second threshold, only the DO function outputs DO1 to drive the dehumidifier 1 to continue dehumidifying the inside of the inverter, while the DO2 and DO3 outputs of the DO function are not output, and the inverter can operate. Step S43: When the internal humidity of the frequency converter drops below the second threshold, the DO function outputs are all stopped, the internal humidity of the frequency converter is good, and all DO function outputs are turned off.

4. A method for detecting bus voltage and temperature / humidity in an explosion-proof frequency converter, characterized in that, The specific device for implementing this method is as follows: When the frequency converter is powered on normally, the AC220V input is connected to the J2 terminal of the frequency converter, which is connected to the 5165AC-DC power module U6, and the output power VCC1 is provided. One path provides power to the microcontroller through diode D3, and the other path provides backup power charging through diode D5 and resistor R16.

5. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, When the inverter is powered on normally, the VCC voltage is greater than the voltage on the supercapacitor, the diode D4 is subjected to reverse voltage and does not conduct, and the backup power supply does not work; when the inverter is powered off, the backup power supply starts to work, and the voltage on the supercapacitor supplies power to the microcontroller through the diode D4. Therefore, it is possible to detect the inverter bus voltage, temperature and humidity even after the inverter is powered off.

6. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The bus voltage detection of the frequency converter is performed by sampling the voltage across the J3 terminal through a resistor divider. The microcontroller detects the voltage across the sampling resistor R12 and performs calculations.

7. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The temperature and humidity sensor module is U3. After collecting the temperature and humidity information inside the inverter cavity, U3 uploads it to the microcontroller CPU for processing via communication.

8. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The microcontroller is U2. U2 processes and calculates the collected DC voltage signal and temperature and humidity signal, and drives the digital tube to poll and display the bus voltage, current temperature and current humidity parameters. When the humidity is too high, it can drive the DO output to control the dehumidifier.

9. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The digital tube circuit is SEG1, which is used to display the inverter's bus voltage, current temperature, and current humidity parameters.

10. The method for detecting bus voltage and temperature / humidity for an explosion-proof frequency converter according to claim 1, characterized in that, The DO function output is J4. When the humidity reaches the protection level, J4 drives the DO output to control the dehumidifier to operate.

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