CN211206604U - Mobile electrical equipment on-line monitoring device - Google Patents
Mobile electrical equipment on-line monitoring device Download PDFInfo
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- CN211206604U CN211206604U CN201922120100.9U CN201922120100U CN211206604U CN 211206604 U CN211206604 U CN 211206604U CN 201922120100 U CN201922120100 U CN 201922120100U CN 211206604 U CN211206604 U CN 211206604U
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Abstract
The mobile electrical equipment on-line monitoring device comprises a box body and a detection meter pen, wherein a three-phase current, voltage and temperature testing port, a liquid crystal display, a power switch and a power indicator lamp are arranged on a panel of the box body, the box body internally comprises a power module, a three-phase current and voltage monitoring module and a temperature monitoring module, the power switch is connected with the power indicator lamp, each monitoring module is respectively connected with the testing port, the detection meter pen is connected with the testing port, the three-phase current monitoring module comprises an open current transformer and a signal conditioning module which are sequentially and electrically connected, the voltage monitoring module comprises a voltage transformer and a voltmeter connected with the secondary side of the voltage transformer, the temperature monitoring module comprises an infrared sensor module, the signal conditioning module and the infrared sensor module are connected with a single chip microcomputer control module, and the single chip microcomputer control module is connected.
Description
Technical Field
The utility model relates to a monitoring device especially designs a portable electrical equipment on-line monitoring device.
Background
At present, important places and important activities are continuously developed, in the traditional major service guarantee, due to the fact that an electrical cabinet (equipment) is aged, an operation monitoring device is not installed or an electrical cabinet (equipment) which is temporarily additionally arranged is lack of the operation monitoring device, although a specially-assigned person is arranged in each major activity area to stare and watch the important equipment, the whole operation state of the equipment cannot be mastered in real time, and no foreknowledge is given before abnormal conditions of the equipment occur, so that unnecessary accidents are caused.
In the prior art, for example, a chinese patent application (application number: CN2018105563059) discloses an application system based on equipment status monitoring, which includes: the device comprises an equipment temperature detection module, a current detection module, a voltage detection module, a harmonic detection module, a processing module, a communication module and a remote server; the equipment temperature detection module, the current detection module, the voltage detection module, the harmonic detection module and the communication module are all electrically connected with the processing module, and the communication module is in signal connection with the remote server; the equipment temperature detection module, the current detection module, the voltage detection module and the harmonic detection module are sequentially arranged on the surface of the electrical equipment; the processing module and the communication module are arranged inside the electrical equipment, the electrical equipment is provided with a power supply module, and the power supply module is electrically connected with the processing module and the communication module respectively. For another example, in the prior art, chinese patent application (application number: CN2018104978187) discloses an automatic fault detection and location system for power lines, which includes: a display unit for detecting real-time data of the power line and outputting status information of the power line according to the real-time data; the alarm unit is used for giving an alarm prompt to workers when the real-time data of the power line is detected to be inconsistent with the safety range of the data in the database; the main control chip is used for receiving signals transmitted by the theoretical calculation and analysis module and transmitting the signals to the display unit, the alarm unit and the internet terminal through the communication module.
However, the above application only provides an idea and does not describe what technical means is adopted to implement the device status monitoring and fault detection, that is, the operation principle of the above application is not described, and only functional modules such as a temperature detection module, a current monitoring module, a voltage monitoring module, a processing module, a display unit and the like are provided, the structural configuration of the above functional modules is not described, and although the above functional modules exist in the prior art, applying all the above prior art functional modules to the present application at the same time is not in the prior art, and the above functional modules can be obtained by a person skilled in the art with creative labor.
For another example, in the prior art, a chinese patent (application number: CN2017212075864) discloses a power distribution monitoring system, which has the technical scheme: the system comprises a microprocessor unit, a three-phase electric parameter metering unit connected with the microprocessor unit, a temperature detection module, a time monitoring unit, an alarm unit and an electric energy quality analyzer; the temperature detection module is used for detecting the temperature of the collected monitoring power equipment and transmitting the detected temperature value to the micro-processing unit; the microprocessor unit is also connected with a communication unit, and the communication unit is used for sending alarm information sent by a current and voltage alarm module, a time alarm module, a temperature alarm module and a harmonic alarm module to a terminal; the three-phase electric parameter calculation unit comprises a three-phase electric parameter metering chip ATT7022, a current transformer and a current transformer, wherein the sampling voltage input of the three-phase electric parameter metering chip ATT7022 adopts a resistance voltage division mode, the current transformer converts the sampling input voltage into a secondary voltage analog signal, and the current transformer converts the sampling input voltage into a voltage analog signal. However, the prior art is not portable, and the adopted technical means has a complex structure and low detection precision, which is not favorable for the application and popularization of products.
SUMMERY OF THE UTILITY MODEL
In order to solve the defects in the prior art, the utility model discloses a mobile electrical equipment online monitoring device which comprises a box body and a detection meter pen, wherein a three-phase current and three-phase voltage testing port, a temperature testing port, a liquid crystal display, a power switch and a power indicator lamp are arranged on a panel of the box body, a power module, a three-phase current monitoring module, a three-phase voltage monitoring module, a temperature monitoring module and a voltmeter are arranged inside the box body, and the mobile electrical equipment online monitoring device is characterized in that the power module is connected with one of three phases of electricity through the power switch and a quick-recoverable protective tube, the power switch is also connected with the power indicator lamp, each monitoring module is respectively connected with each testing port on the panel of the box body, the detection meter pen can be connected with the testing port, the three-phase current monitoring module comprises an open current transformer and a signal conditioning module which are sequentially electrically connected, the three-phase voltage monitoring module comprises a voltage transformer and a secondary side meter connected with the voltage transformer, the temperature monitoring module comprises an infrared sensor module, the signal module in the three-phase current monitoring module and the infrared sensor module are connected with a single chip computer control L.
Preferably, the output end of the open type current transformer is connected with an L M324 integrated operational amplifier, two reverse diodes are added to the input end of the integrated operational amplifier to play a role in protecting the operational amplifier, and a feedback resistor connected with the input end of the negative end of the integrated operational amplifier is a precision resistor.
Preferably, the L M324 integrated operational amplifier output signal is first half-wave rectified by the first operational amplifier so that the ac signal only remains negative for the negative half cycle, and then the negative half cycle of the inverted result is connected to the inverting input of the operational amplifier, and then an adder is connected to the positive input to add the input ac signal to twice the half-wave rectified signal to obtain a full-wave forward signal.
Preferably: the full-wave forward signal is connected with the A/D conversion module; the A/D conversion module adopts a chip with the model number of ADC0809, and the output end of the chip ADC0809 is connected with an I/O port of a singlechip AT89C 51; the ADC0809 chip is externally connected with a clock signal with the frequency of 500 kHz.
Preferably: the voltage transformer is an electromagnetic induction type voltage transformer.
Preferably, the infrared sensor module comprises a high-precision temperature measuring chip with the model number of M L X90615.
Preferably, the infrared sensor module is connected to the single-chip microcomputer control module in an SMBus mode, pins SDA and SC L in the M L X90615 chip are connected with an I/O port of the single-chip microcomputer AT89C51, and are connected with the power supply voltage of 3.3V through a pull-up resistor of 20k omega.
Preferably: the three-phase voltage monitoring module adopts three single-phase transformers to form a three-phase voltage transformer and is connected with a three-phase bus through a fuse and a relay normally open contact which are connected in sequence.
Has the advantages that:
1. the current transformer adopts an open type transformer, the open type current transformer has the characteristics of convenient measurement and convenient use, the current transformer and a voltage measuring probe (clamp) are connected with the multifunctional meter through a telescopic winding wire, and the actual voltage and current are displayed;
2. the quick plug connector is adopted for connection, the space utilization rate of the detection equipment is optimized, and the mobility and the portability of the equipment are enhanced.
3. On the basis of not changing the original electrical equipment, the voltage, the current and the temperature of the equipment which is not in line with the installation detection device are monitored in real time, so that major activity support personnel can conveniently master the operation data of the equipment in real time, and the probability of accidents is reduced.
Drawings
Fig. 1 is the structure sketch of the mobile electrical equipment on-line monitoring device of the utility model.
Fig. 2 is the control structure diagram of the on-line monitoring device for mobile electrical equipment of the utility model.
Fig. 3 is the utility model discloses portable electrical equipment on-line monitoring device three-phase current monitoring control schematic diagram.
Fig. 4 is the current-voltage conversion circuit schematic diagram in the three-phase current monitoring module of the mobile electrical equipment on-line monitoring device of the utility model.
Fig. 5 is the utility model discloses signal conditioning circuit schematic diagram in the mobile electrical equipment on-line monitoring device three-phase current monitoring module.
Fig. 6 is the utility model discloses analog-to-digital conversion chip and singlechip connecting circuit schematic diagram in the mobile electrical equipment on-line monitoring device three-phase current monitoring module.
Fig. 7 is the structure block diagram of the middle infrared monitoring module of the mobile electrical equipment on-line monitoring device of the utility model.
Fig. 8 is a structural block diagram of a M L X90615 chip in the temperature monitoring module of the mobile electrical device online monitoring apparatus of the present invention.
Fig. 9 is a circuit diagram of the M L X90615 chip and the single chip microcomputer in the temperature monitoring module of the mobile electrical device online monitoring device of the present invention.
Fig. 10 is a schematic diagram of the circuit connection of the voltage monitoring module of the online monitoring device for mobile electrical equipment of the present invention.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.
An on-line monitoring device for mobile electrical equipment comprises a box body, a three-phase current and three-phase voltage testing port, a temperature testing port, a liquid crystal display, a power switch and a power indicator lamp are arranged on a panel of the box body, a power module, a three-phase current and three-phase voltage monitoring module, a temperature monitoring module and a detection meter pen are arranged inside the box body, the power module is connected with one of three-phase current through a power switch and a quick-recovery fuse tube, the power switch is further connected with the power indicator lamp, each monitoring module is respectively connected with each testing port on the panel of the box body, the detection meter pen can be connected with the testing port, the three-phase current monitoring module comprises an open type current transformer and a signal conditioning module which are sequentially electrically connected, the three-phase voltage monitoring module comprises a voltage transformer and a voltage meter connected with the voltage transformer, the temperature monitoring module comprises an infrared sensor module, the signal conditioning module in the three-phase current monitoring module and the infrared sensor module are connected with a single-chip control module, the single-phase current monitoring module is connected with a semi-phase current transformer, a semi-frequency amplifier (SMBC) and a semi-phase voltage Amplifier (AC) module, a single-phase current Amplifier (AC) amplifier (S-AC) module, a single-phase current amplifier (S-AC) module, a single-phase current amplifier (S) module, a single-phase current amplifier (S-AC) module, a single-phase current amplifier (S-D) module, a single-D-phase current amplifier (S-D) module, a single-D-.
The following describes the structural configurations and operating principles of the three-phase current monitoring module, the three-phase voltage monitoring module, and the temperature monitoring module in detail.
The working principle and the structure of the three-phase current monitoring module are shown in the attached figures 3-6 of the specification.
The three-phase current monitoring module provided by the invention obtains the real-time value of the current by sampling the three-phase current and processing the three-phase current, processes and calculates the data by using the single chip microcomputer, displays the result on L CD in real time, and compares and observes the data of the displayed current so as to detect the working condition of the three-phase current in the electric box equipment.
The three-phase current monitoring module comprises an open type current transformer, a signal conditioning module and a single chip microcomputer control module which are sequentially and electrically connected.
The open type current transformer collects three-phase current signals in the electric box, converts the current signals into voltage signals, converts analog signals into digital signals through an A/D converter in the signal conditioning module and then transmits the digital signals to the single chip microcomputer control module, and the collected current signals are displayed on an L CD liquid crystal screen through the single chip microcomputer control module.
Please refer to fig. 4, which is a schematic diagram of a conversion circuit for converting a current signal into a voltage signal after a current transformer collects a three-phase current, the circuit principle adopts an L M324 integrated operational amplifier as a main component for current conversion, the voltage after current conversion can be controlled according to the size of a feedback resistor R3, the resistors R1, R2 and R3 for feedback are required to be precise resistors, and two reverse diodes are added to the input end of the L M324 integrated operational amplifier for the purpose of protecting the operational amplifier.
The phase current is converted into a voltage signal by the circuit, and the converted voltage signal is weak, so the voltage signal needs to be subjected to signal processing to enhance the signal strength. Referring to fig. 5, the circuit schematic diagram firstly uses an operational amplifier to implement half-wave rectification, so that the ac signal only remains a negative half cycle, and since the operational amplifier is connected to the inverting input terminal of the operational amplifier, the result is an inverted negative half cycle, and then a precise adder is used to add the input ac signal and twice the half-wave rectified signal by using the non-inverting input terminal, and finally the signal in the positive direction of the full wave is obtained. The operational amplifier adopted in the circuit schematic diagram can be selected from op07 chips or 741 chips and the like.
The acquired current signals are processed by the circuit diagrams shown in fig. 4-5 to form stable and reliable voltage signals, and then the stable and reliable voltage signals are subjected to A/D conversion, the type of an A/D conversion chip adopted by the invention adopts ADC0809, the chip ADC0809 is a CMOS component with 8-bit A/D converter, 8-way multi-way switch and microprocessor compatible control logic, is a successive approximation type A/D converter and can be directly interfaced with a singlechip AT89C51, in addition, as no clock circuit is arranged in the ADC0809, the required clock signals have to be provided by the outside, and the frequency is usually 500 kHz.
The open type current transformer adopted by the invention has the transformation ratio of 2000: 1, namely, if the current input at the primary side is 5A, the effective value of the current at the secondary side is 2.5mA, the sampling resistance is 1k ohm because the input voltage of AD sampling is required to be 0.3-5V, a 12MHz crystal oscillator is used for a singlechip, a fixed 6-frequency division clock frequency, namely 2MHz, is sent out from an A L E port, a 4-frequency division circuit is required to be connected externally, and two independent D triggers, such as 74L S74, can be selected to finish the frequency division purpose.
In addition, because the A, B, C phases of the three-phase current are selected by adopting the multi-way switch, the conversion resource of AD is utilized in a time-sharing way, and therefore, the problem of three-phase alternating current time-sharing and channel-dividing exists, so that the invention adopts the mode that 66 sampling points can be sampled in one period, namely 50Hz, and 50 sampling points are taken in each phase in one period in consideration of the sampling reliability. If the voltage effective value formula:
discretization, in which a limited number of sampled voltage digital values in a period are used to replace a continuously changing voltage value in a period, includes:
in the formula: delta TmThe time interval of two adjacent sampling is shown, and Um is the voltage sampling instantaneous value of the m-1 time interval; n is the number of sampling points in 1 period; if the time intervals of two adjacent samples are equal, i.e. Δ TmA constant Δ T, considering that N ═ 1 (T/Δ T) +1, there are
The sampling value is calculated by the voltage formula, the influence of 50 sampling points of each phase of each period on the sampling precision can be analyzed, meanwhile, the average value is calculated and compared with the theoretical calculation value, the average value of errors is found to compensate the output signal, and the effective value of the current amplitude is displayed through an L CD display screen.
The working principle and structure of the temperature monitoring module are shown in the accompanying fig. 7-9 of the description.
The utility model discloses a temperature measurement chip of high accuracy including Melexis company production in the temperature monitoring module, its model is M L X90615, this chip inner structure comprises infrared temperature sensor, low noise amplifier, an AD converter, DSP unit, pulse width modulation circuit and logic control circuit (see shown in figure 8), the temperature signal of thermocouple output gives analog/digital converter behind the internal operational amplifier, 16 digit volume of its output is exported after low pass filter handles, this output keeps in the internal RAM unit as the measurement result, can read through SMBus, its measurement result simultaneously is sent back level digital pulse width modulation circuit, export the test result with PWM mode, infrared sensor selects to be connected to the singlechip with SMBus mode, its connecting circuit schematic please refer to figure 9, wherein, SDA and SC L pin are connected with the singlechip I/O mouth in the M L X90615 chip, and pull-up resistance through 20k omega links to supply voltage 3.3V.
The single chip microcomputer can write data into an EEPROM in the sensor by sending a command to the infrared sensor and can also read out temperature data stored in the RAM, when the infrared sensor M L X90615 receives an external infrared signal and is processed in the sensor, a digital temperature signal is output to the single chip microcomputer, the single chip microcomputer processes the read data and displays the temperature data on a L CD1602, the direction of a temperature acquisition signal is that the single chip microcomputer points to a liquid crystal module, so that an enable end/OE is grounded, a DIR end is connected with a VCCA end, and a data and control port of the L CD1602 is connected with an I/O port of the single chip microcomputer after being converted by an SN 74L VCC3245A chip.
In addition, in the temperature monitoring module, 3.3V power supply needs to be carried out on an AT89C51 singlechip and an infrared sensor M L X90615, while the power supply voltage needed by the liquid crystal display module L CD1602 is 5 V.the power supply design adopts a 9V battery for power supply so as to increase the portability of the infrared thermometer, and 2L M317 are adopted to convert the 9V battery voltage into 5V and 3.3V respectively so as to meet the requirements of 2 power supply voltages.
The working principle and structure of the phase voltage monitoring module are shown in fig. 10 in the specification.
In order to save the design cost, the phase voltage detection module comprises a voltage transformer and a voltmeter, phase voltage is collected through the voltage transformer, and collected phase voltage signals are directly connected with the voltmeter to display three-phase voltage.
The specific circuit is shown in figure 10 in the specification. The utility model discloses a three-phase voltage transformer is constituteed to three single-phase transformers to be connected with the three-phase bus through order connection fuse, relay normally open contact. Because the impedance of the voltage transformer is small, once the secondary side is short-circuited, the current rapidly increases and burns out the coil, therefore, the primary side of the voltage transformer is connected with a fuse and a relay switch, and the secondary side is reliably grounded so as to avoid equipment accidents caused by high potential to the ground when the primary side and the secondary side are insulated and damaged. In addition, the utility model discloses voltage transformer's connection adopts three-phase three-column mutual-inductor's mode of connection, and this kind of connection advantage is because high-pressure side neutral point ground connection, so can reduce insulating level, reduce cost, and voltage transformer group is according to the phase voltage design, can both measure line voltage and can measure the phase voltage; in addition, the secondary side open triangular auxiliary winding can be used for insulation monitoring.
The utility model discloses do not possess installation condition monitoring devices's old equipment, interim equipment running state monitoring devices in the major activity scene of mainly used, important place, also can be used to the failure analysis and the state aassessment of equipment. The device has the characteristics of simple structure, portability, comprehensive measured data, high cost performance and the like, can monitor corresponding equipment at any time as required in the guarantee of various major activities, and master the operation parameters of the equipment at any time, so that the service guarantee work is excessive to the scientific and intelligent level.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the above embodiments, and that the principles of the present invention may be applied to any other embodiment without departing from the spirit and scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (8)
1. The mobile electrical equipment on-line monitoring device comprises a box body and a detection meter pen, wherein a three-phase current and three-phase voltage testing port, a temperature testing port, a liquid crystal display, a power switch, a power indicator lamp and a voltmeter are arranged on a panel of the box body, a power module, a three-phase current monitoring module, a three-phase voltage monitoring module and a temperature monitoring module are arranged inside the box body, and the mobile electrical equipment on-line monitoring device is characterized in that the power module is connected with one of three phases of electricity through the power switch and a quick-recovery fuse tube, the power switch is also connected with the power indicator lamp, each monitoring module is respectively connected with each testing port on the panel of the box body, the detection meter pen can be connected with the testing port, the three-phase current monitoring module comprises an open type current transformer and a signal conditioning module which are sequentially and electrically connected, the three-phase voltage monitoring module comprises a voltage transformer and a voltmeter connected with the secondary side of the voltage transformer, the temperature monitoring module comprises an infrared sensor module, the signal conditioning module in the three-phase current monitoring module and the infrared sensor module in the temperature monitoring module are.
2. The on-line monitoring device of mobile electrical equipment as claimed in claim 1, wherein the output end of the open type current transformer is connected with L M324 integrated operational amplifier, two reverse diodes are added to the input end of the integrated operational amplifier to protect the operational amplifier, and a feedback resistor connected between the output end of the integrated operational amplifier and the input end of the negative terminal is a precision resistor.
3. The in-line monitoring device of claim 2, wherein the L M324 integrated operational amplifier outputs a signal that is first half-wave rectified by the first operational amplifier so that the AC signal only remains negative for the negative half-cycle, and then the negative half-cycle is inverted by the inverting input of the operational amplifier, and then connected to an adder that adds the input AC signal to twice the half-wave rectified signal by the non-inverting input to obtain a full-wave positive signal.
4. A mobile electrical equipment on-line monitoring device according to claim 3, characterized in that: the full-wave forward signal is connected with the A/D conversion module; the A/D conversion module adopts a chip with the model number of ADC0809, and the output end of the chip ADC0809 is connected with an I/O port of a singlechip AT89C 51; the ADC0809 chip is externally connected with a clock signal with the frequency of 500 kHz.
5. A mobile electrical equipment on-line monitoring device according to claim 1, characterized in that: the voltage transformer is an electromagnetic induction type voltage transformer.
6. The on-line monitoring device for the mobile electrical equipment as claimed in claim 1, wherein the infrared sensor module comprises a high-precision temperature measuring chip with the model number of M L X90615.
7. The mobile electric equipment on-line monitoring device of claim 6, wherein the infrared sensor module is connected to the single chip microcomputer control module in SMBus mode, SDA and SC L pins in the M L X90615 chip are connected with the I/O port of the single chip microcomputer AT89C51, and are connected with the supply voltage of 3.3V through a pull-up resistor of 20k Ω.
8. A mobile electrical equipment on-line monitoring device according to claim 1, characterized in that: the three-phase voltage monitoring module adopts three single-phase transformers to form a three-phase voltage transformer and is connected with a three-phase bus through a fuse and a relay normally open contact which are connected in sequence.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113218509A (en) * | 2021-04-28 | 2021-08-06 | 三峡大学 | Hand-held electrical instrument |
| CN114035480A (en) * | 2021-11-16 | 2022-02-11 | 西安西电电力系统有限公司 | Pulse generator based on C51 singlechip |
-
2019
- 2019-12-02 CN CN201922120100.9U patent/CN211206604U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113218509A (en) * | 2021-04-28 | 2021-08-06 | 三峡大学 | Hand-held electrical instrument |
| CN114035480A (en) * | 2021-11-16 | 2022-02-11 | 西安西电电力系统有限公司 | Pulse generator based on C51 singlechip |
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