CN114899798A

CN114899798A - Circuit monitoring method based on three-phase motor and related equipment

Info

Publication number: CN114899798A
Application number: CN202210353131.2A
Authority: CN
Inventors: 刘西广; 周岐文; 申永利; 邓敦毅; 朱良军; 贾润枝; 崔华义; 王士龙
Original assignee: SHANDONG HIGHWAY ENGINEERING TECHNOLOGY RESEARCH CENTER CO LTD; Tianjin Haidel Technology Co ltd; China National Chemical Communications Construction Group Coltd
Current assignee: SHANDONG HIGHWAY ENGINEERING TECHNOLOGY RESEARCH CENTER CO LTD; Tianjin Haidel Technology Co ltd; China National Chemical Communications Construction Group Coltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-08-12

Abstract

The application provides a circuit monitoring method based on a three-phase motor, which comprises the following steps: monitoring three-phase current and three-phase voltage of a three-phase motor by using an MCU module to obtain a plurality of monitoring data, analyzing the plurality of monitoring data and obtaining a monitoring result, and determining an alarm level according to the monitoring result; responding to the first-level alarm of the alarm level, and controlling the three-phase motor to work by using the MCU module; and responding to the second-level alarm of the alarm level, sending the monitoring data to an upper computer through a communication module, feeding back a control signal to the MCU module by using the upper computer according to the monitoring data, and controlling the three-phase motor to work by using the MCU module according to the control signal. The method provided by the application can monitor the current and voltage parameters of the three-phase motor in real time and provide real-time working data of the three-phase motor for the upper computer, can judge the real-time working condition of the three-phase motor through single equipment, finds out the working data abnormality of the three-phase motor in time, and guarantees the safe operation of the three-phase motor while saving the equipment cost.

Description

Circuit monitoring method based on three-phase motor and related equipment

Technical Field

The application relates to the technical field of motor circuits, in particular to a circuit monitoring method based on a three-phase motor and related equipment.

Background

To the three-phase motor in fan, the water pump for the building, prior art is through DDC (direct digital controller) monitoring, and DDC is through detecting contactor, thermal relay's auxiliary contact closed condition, comes the start-stop and the fault condition of monitoring motor to control motor switch through controlling secondary circuit relay, this scheme exists following not enoughly: auxiliary equipment is required to be installed to judge the working condition of the motor, so that the overall cost is high; data abnormity of faults caused by phase loss, poor contact, zero sequence voltage and the like cannot be found; real-time data cannot be provided for a user in a communication mode; and a large amount of pipelines are constructed, so that the equipment cost is further increased.

Disclosure of Invention

In view of the above, an object of the present application is to provide a circuit monitoring method based on a three-phase motor and a related device.

In view of this, the present application provides a circuit monitoring method based on a three-phase motor, where the method is implemented by using a circuit monitoring system, the circuit monitoring system includes an MCU module, a communication module, and an upper computer, and the method includes: monitoring three-phase current and three-phase voltage of a three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyzing the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determining an alarm level according to the monitoring result; responding to the alarm level as a first-level alarm, and controlling the three-phase motor to work by using the MCU module; and responding to the fact that the alarm level is a secondary alarm, sending the monitoring data to the upper computer through the communication module, feeding back a control signal to the MCU module by using the upper computer according to the monitoring data, and controlling the three-phase motor to work by using the MCU module according to the control signal.

Optionally, the alarm level comprises a zero level alarm, a first level alarm, and the second level alarm; the determining an alarm level according to the monitoring result comprises: determining the alarm level as a zero-level alarm in response to not including any abnormal value in the monitoring result; determining the alarm level as a primary alarm in response to the monitoring results including voltage/current phase loss, motor stalling/blocking, circuit short circuit, voltage lower than an undervoltage threshold, voltage higher than an overvoltage threshold, current higher than an overload threshold, and current peak pulse frequency higher than a pulse threshold, wherein the undervoltage threshold, the overvoltage threshold, the overload threshold and the pulse threshold are all preset; determining the alarm level as a secondary alarm in response to the monitoring result including an abnormal value but not including a voltage/current phase loss, a motor stalling/encountering resistance, a circuit short, a voltage below the undervoltage threshold, a voltage above the overvoltage threshold, a current above the overload threshold, and a current peak pulse frequency above the pulse threshold.

Optionally, the responding to the alarm level being a primary alarm, controlling the three-phase motor to work by using the MCU module, includes: and responding to the first-level alarm of the alarm level, stopping the three-phase motor by using the MCU module, and sending the monitoring data to the upper computer through the communication module.

Optionally, when the monitoring data is sent to the upper computer through the communication module, the data sending mode of the monitoring data includes a number form and a grouping form, and the number form includes: determining the serial number of each monitoring data, and sending the changed monitoring data to the upper computer in the form of serial number plus value; the grouping form comprises: dividing the plurality of monitoring data into a plurality of groups, each of the groups comprising a plurality of the monitoring data; determining the group number of each group of monitoring data, and sending the group where the changed monitoring data is located to the upper computer in the form of adding the group number and the numerical values of all members in the group; the monitoring data is sent to the upper computer through the communication module, and the monitoring data sending method comprises the following steps: and determining the data sending mode according to the monitoring data, and sending the monitoring data to the upper computer through the communication module based on the data sending mode.

Optionally, the determining the data sending manner according to the monitoring data includes: respectively calculating the number of bytes required by the monitoring data for transmitting the data in the number form and the grouping form, and selecting a data transmission mode with smaller number of bytes; the numbering form is selected in response to the same number of bytes required for both data transmission modes.

Optionally, the circuit monitoring system further comprises a manual/automatic switching circuit, the manual/automatic switching circuit comprises a manual control switch, a device start-stop switch, a normally open relay and a normally closed relay, the normally open contact of the three-phase motor is connected with the input end of the manual control switch, the common end of the three-phase motor is connected with the second output end of the normally closed relay, the input ends of the normally open relay and the normally closed relay are both connected with the MCU module, the first output end of the normally open relay is connected with the OFF end of the manual control switch, the second output end of the normally open relay is connected with the first output end of the normally closed relay, the first output end of the normally closed relay is also connected with the input end of the equipment start-stop switch, and the ON end of the equipment start-stop switch is connected with the ON end of the manual control switch; the method further comprises the following steps: setting the manual control switch to an OFF state in response to a need for manually controlling operation of the three-phase motor; responding to the fact that the three-phase motor needs to be manually controlled to work while the MCU module monitors the three-phase current and the three-phase voltage, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by utilizing the equipment start-stop switch; and responding to the requirement of completely manually controlling the three-phase motor to work, cutting off the power supply of the MCU module, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by using the equipment start-stop switch.

Optionally, the method further comprises: monitoring the temperature of the three-phase motor, the closing condition of a box door and the frequency output of a frequency converter by using the MCU module to obtain a plurality of auxiliary data; and sending the auxiliary data to the upper computer through the communication module, feeding back an auxiliary control signal to the MCU module by using the upper computer according to the auxiliary data, and controlling the three-phase motor to work by using the MCU module according to the auxiliary control signal.

Based on the same inventive concept, the application also provides a circuit monitoring device based on the three-phase motor, the device is implemented by using a circuit monitoring system, the circuit monitoring system comprises an MCU module, a communication module and an upper computer, and the device comprises: the monitoring module is configured to monitor three-phase current and three-phase voltage of the three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyze the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determine an alarm level according to the monitoring result; the primary alarm response module is configured to respond to the alarm level being primary alarm and control the three-phase motor to work by the MCU module; and the secondary alarm response module is configured to respond to the alarm level being a secondary alarm, send the monitoring data to the upper computer through the communication module, utilize the upper computer to feed back a control signal to the MCU module according to the monitoring data, and utilize the MCU module to control the three-phase motor to work according to the control signal.

Based on the same inventive concept, the application further provides an electronic device, which comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor implements any one of the three-phase motor-based circuit monitoring methods when executing the program.

Based on the same inventive concept, the present application further provides a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are configured to cause a computer to execute any one of the three-phase motor-based circuit monitoring methods.

From the above, it can be seen that the application provides a circuit monitoring method based on a three-phase motor, the method is implemented by using a circuit monitoring system, the circuit monitoring system comprises an MCU module, a communication module and an upper computer, and the method comprises: monitoring three-phase current and three-phase voltage of a three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyzing the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determining an alarm level according to the monitoring result; responding to the alarm level as a first-level alarm, and controlling the three-phase motor to work by using the MCU module; and responding to the fact that the alarm level is a secondary alarm, sending the monitoring data to the upper computer through the communication module, feeding back a control signal to the MCU module by using the upper computer according to the monitoring data, and controlling the three-phase motor to work by using the MCU module according to the control signal. The method provided by the application can monitor the current and voltage parameters of the three-phase motor in real time and provide real-time working data of the three-phase motor for the upper computer, can judge the real-time working condition of the three-phase motor through single equipment, finds out the working data abnormality of the three-phase motor in time, and guarantees the safe operation of the three-phase motor while saving the equipment cost.

Drawings

In order to more clearly illustrate the technical solutions in the present application or the related art, the drawings needed to be used in the description of the embodiments or the related art will be briefly introduced below, and it is obvious that the drawings in the following description are only embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a circuit monitoring system according to an embodiment of the present disclosure;

FIG. 2 is a schematic flow chart of a circuit monitoring method based on a three-phase motor according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a manual/automatic switching circuit according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a circuit monitoring device based on a three-phase motor according to an embodiment of the present application;

fig. 5 is a schematic diagram of a hardware structure of an electronic device according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to specific embodiments and the accompanying drawings.

It should be noted that technical terms or scientific terms used in the embodiments of the present application should have a general meaning as understood by those having ordinary skill in the art to which the present application belongs, unless otherwise defined. The use of "first," "second," and similar terms in the embodiments of the present application do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

An embodiment of the present application provides a circuit monitoring method based on a three-phase motor, where the method is implemented by using a circuit monitoring system, as shown in fig. 1, the circuit monitoring system includes an MCU (micro controller Unit) module, a communication module, and an upper computer, as shown in fig. 2, the method includes:

step S101, monitoring three-phase current and three-phase voltage of a three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyzing the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determining an alarm level according to the monitoring result.

Step S102, responding to the alarm level as a first-level alarm, and controlling the three-phase motor to work by using the MCU module; and responding to the fact that the alarm level is a secondary alarm, sending the monitoring data to the upper computer through the communication module, feeding back a control signal to the MCU module by using the upper computer according to the monitoring data, and controlling the three-phase motor to work by using the MCU module according to the control signal. The alarm is divided into a plurality of levels, wherein the influence of the first-level alarm is the largest, if the first-level alarm exists, the larger fault exists in the three-phase motor, at the moment, the MCU module controls the motor to work before sending data to the upper computer, specifically, the motor stops working, the motor can be guaranteed to stop working before the fault is aggravated, the industrial production loss can be avoided to a certain extent, and the safety of the industrial production is guaranteed; if the secondary alarm exists, the situation that the safe operation of the motor cannot be influenced temporarily due to the fault of the three-phase motor is shown, at the moment, the working data of the motor is firstly sent to the upper computer, and then the upper computer (or a technician controlling the upper computer) judges what control signal is to be sent to the motor, so that the industrial production efficiency is ensured.

The method provided by the embodiment of the application can monitor the current and voltage parameters of the three-phase motor in real time and provide real-time working data of the three-phase motor for the upper computer, can judge the real-time working condition of the three-phase motor through single equipment, can find out the abnormality of the working data of the three-phase motor in time, and guarantees the safe operation of the three-phase motor while saving the equipment cost. By using the method provided by the embodiment of the application to monitor the work of the three-phase motor, the construction cost can be reduced by 40%, the pipeline laying amount can be reduced by 90% and the labor input can be reduced by 80% on the whole engineering, and the energy consumption can be reduced by 5% -15%.

The method provided by the embodiment of the application is mainly used for equipment such as a water pump and a fan driven by a three-phase motor, and during specific implementation, the MCU module is connected with a distribution box/cabinet of the equipment. The MCU module has the functions of monitoring, analyzing and alarming full electric parameters, is internally provided with an operation model of the motor, and can automatically learn and record according to the operation condition of the motor. The device applying the method provided by the embodiment of the application can replace the DDC and other peripheral auxiliary equipment in the prior art, such as a secondary circuit of a distribution box/cabinet, a metering ammeter, an electric fire monitor, a phase loss protector, an over-current and under-current protector and the like.

In a specific embodiment, as shown in fig. 1, the MCU module measures three-phase current and three-phase voltage of the motor by using the electric quantity measurement module, specifically, the electric quantity measurement module directly measures three-phase voltage of the main circuit of the motor, measures three-phase current of the main circuit of the motor by using a current transformer in the electric quantity measurement module, and receives monitoring data through an SPI Interface (Serial Peripheral Interface) of the MCU module. In a specific embodiment, as shown in fig. 1, the MCU module controls the operation of the motor through the I/O interface. In a specific implementation, the MCU module may be an 8051 series single chip microcomputer, and in a more specific embodiment, the model of the MCU module is 8a8k64s4a 12.

In a specific embodiment, the circuit monitoring system further comprises a power supply module, the power supply module is connected with a three-phase power supply of the motor through a switch, any phase of the ABC three phases of the motor is electrified, and the power supply module can work. When the circuit monitoring system works, the power supply module supplies power to other modules in the circuit monitoring system through the voltage conversion module.

In a specific embodiment, the MCU module is internally provided with a program storage unit for storing a driver and a system upgrade management program, and the application program is stored in an external memory for online upgrade. The MCU module stores the monitoring data into the storage unit periodically and provides real-time data and historical data for the upper computer. The storage unit adopts a static RAM (Random Access Memory) or a high-capacity FLASH (FLASH Memory) which is powered by a battery, can be used for storing history records and timing switches for a long time, and simultaneously ensures the service life under the condition of uninterrupted reading and writing.

In a specific embodiment, the MCU module further comprises a display module and a keyboard module, and in actual use, a technician can directly control the MCU module to work or modify the parameter configuration of the MCU module through the display module and the keyboard module.

In some embodiments, the alarm levels include a zero level alarm, a first level alarm, and the second level alarm; the determining an alarm level according to the monitoring result in the step S101 includes:

determining the alarm level as a zero-level alarm in response to not including any abnormal value in the monitoring result; determining the alarm level as a primary alarm in response to the monitoring results including voltage/current phase loss, motor stalling/blocking, circuit short circuit, voltage lower than an undervoltage threshold, voltage higher than an overvoltage threshold, current higher than an overload threshold, and current peak pulse frequency higher than a pulse threshold, wherein the undervoltage threshold, the overvoltage threshold, the overload threshold, and the pulse threshold are all preset; determining the alarm level as a secondary alarm in response to the monitoring result including an abnormal value but not including a voltage/current phase loss, a motor stalling/encountering resistance, a circuit short, a voltage below the undervoltage threshold, a voltage above the overvoltage threshold, a current above the overload threshold, and a current peak pulse frequency above the pulse threshold.

According to the embodiment of the application, various different faults/data abnormalities of the three-phase motor are analyzed, the influence of each fault/data abnormality on the work of the three-phase motor is obtained, different alarm levels are determined for each fault/data abnormality of the three-phase motor, and the motor can work safely and efficiently.

In a specific embodiment, the MCU module analyzes the monitoring data and obtains a monitoring result according to the built-in data model and configuration parameters, and analyzes whether the monitoring result is abnormal, and the specific process includes: the method comprises the steps that equipment information (equivalent to configuration information of a motor) is input into an MCU module, wherein the equipment information comprises equipment types (a fan, a water pump and the like), power, rotating speed and whether the motor is directly started or not (if not, options such as self-coupling voltage reduction, soft start, frequency conversion start and the like are given), the MCU module inquires an internal data model table (refer to technical conditions (machine seat numbers 63-355) of GB/T28575 and 2020 YE3 series (IP55) three-phase asynchronous motors) according to the information, alarm threshold values (namely an under-voltage threshold value, an overpressure threshold value, an overload threshold value and a pulse threshold value) are automatically generated, the parameters are displayed in a configuration interface, and meanwhile, the parameters are allowed to be manually adjusted. And the MCU module reads monitoring data through the SPI bus, compares the monitoring data with set threshold parameters, and analyzes the monitoring data to obtain a monitoring result.

In one specific embodiment, the parameter anomaly alarm levels are three levels: reminding, warning and linking, wherein the reminding level and the warning level both belong to the second-level alarm level, the linking level belongs to the first-level alarm level, and the zero-level alarm level does not give an alarm. The reminding level is defined as the condition that the numerical value exceeds the normal value by a certain proportion, and the risk is possibly generated in the continuous development; the alarm level is defined as that the numerical value exceeds the normal value more, and the continuous development is likely to cause the damage of equipment (namely a motor); the linkage grade is defined as a numerical value which is seriously beyond a normal value, and continuous development necessarily causes equipment damage. The reminder level typically compares the real-time data with historical data, e.g., a start time of more than 20% of the average, as a start anomaly for the reminder level. The alarm level typically compares real-time data with well-defined parameters, such as over-voltage and under-voltage alarms for voltage, and alarms when a specified threshold (where the range of thresholds is less than the under-voltage threshold, the over-voltage threshold, the overload threshold, and the pulse threshold) is exceeded, according to certain data in the model. The linkage level, namely the primary alarm level is the most urgent alarm level, such as phase loss and locked rotor alarm, and the power supply of the equipment needs to be cut off immediately for protecting the equipment. During the concrete implementation, when sending the monitoring result to the host computer, the accessible shows the sign and distinguishes warning rank, warning rank and linkage rank, for example, reminds the rank to show for green alarm, and the warning rank shows for yellow alarm, and the linkage rank shows for red alarm, and the unusual degree of severity of visual feedback data.

In specific implementation, the process of obtaining the monitoring result according to the monitoring data is as follows: 1) short circuit judgment: the real-time measured value of any phase current is greater than or equal to a preset short-circuit protection threshold value (for example, 7 times of rated current), and the alarm level is first-level alarm; 2) and (3) undervoltage judgment: the condition that the phase voltage and the line voltage of one phase or multiple phases in the three-phase voltage are too low occurs, if the voltage is not lower than the undervoltage threshold value, the alarm level is a secondary alarm, and if the voltage is lower than the undervoltage threshold value, the alarm level is a primary alarm; 3) and (3) phase loss judgment: one phase of the three-phase power has no voltage or current, and the alarm level is first-level alarm; 4) and (3) overpressure judgment: the method comprises the following steps that when the phase voltage and the line voltage of one phase or multiple phases of three-phase voltage are overhigh, if the voltage is not higher than the overpressure threshold value, the alarm level is a secondary alarm, and if the voltage is higher than the overpressure threshold value, the alarm level is a primary alarm; 5) and (4) overload judgment: the current exceeds the current constant value of the motor (the current constant value is generally set to be 1.1-1.3 times of the rated current of the motor), the current lasts for a certain time (20-60 s), the overload judgment adopts an integral algorithm, the difference value between the current measured in real time and the rated current is accumulated, when the accumulated value is larger than a set value, if the accumulated value does not exceed the overload threshold value, the alarm level is a secondary alarm, and if the accumulated value exceeds the overload threshold value, the alarm level is a primary alarm; 6) and (3) locked rotor/blocked judgment: when the motor/equipment is locked or blocked, in the starting stage of the motor, the starting current is 4-7 times of the normal current, the duration time of the starting stage is long, and the locked or blocked state is judged to occur at the moment; in the motor operation stage, judging whether the locked rotor/resistance is generated or not according to the locked rotor/resistance current and the motor parameters; 7) and (3) ignition judgment: and under the condition of poor contact of the circuit contact, a plurality of current peak pulses occur in a short time, if the frequency of the current peak pulses is not higher than the pulse threshold, the alarm level is a secondary alarm, and if the frequency of the current peak pulses is higher than the pulse threshold, the alarm level is a primary alarm.

In some embodiments, in response to the alarm level being a primary alarm, the step S102 of controlling the three-phase motor to operate by using the MCU module includes: and responding to the fact that the alarm level is a first-level alarm, stopping the three-phase motor by using the MCU module, and sending the monitoring data to the upper computer through the communication module. If the motor has major faults, the motor stops working immediately, so that the loss of industrial production can be avoided to a certain extent, and the safety of industrial production is ensured. The MCU module controls the work of a relay inside the motor through the I/O interface, and cuts off an output loop of the motor, so that the motor stops working. After the motor is controlled to stop working through the MCU module, if the motor needs to be started again, the configuration interface needs to be reset.

In a specific embodiment, the communication module is composed of a plurality of interface chips, including an RS-485(MODBUS/RTU) chip for connecting with a third party device; the wireless communication (LORA) chip is used for wirelessly communicating with an upper computer; the CAN communication chip is used for wired communication with an upper computer, the wired communication and the wireless communication CAN work simultaneously, but a main communication mode needs to be defined in advance, the upper computer of the wired communication and the wireless communication CAN be the same gateway or different gateways, and the wired communication CAN be directly connected with a third party gateway or equipment. When information contradiction occurs between the two kinds of communication, the main communication is used as the standard; and the Bluetooth communication chip is used for parameter configuration and field data checking. The communication module in the embodiment of the application supports a data bidirectional subscription function, the gateway of the upper computer can subscribe different data to the MCU module according to different time intervals, and the MCU module can send the data to the gateway through the communication module at regular time according to the specified time intervals.

In some embodiments, when the monitoring data is sent to the upper computer through the communication module in step S102, the data sending mode of the monitoring data includes a number form and a packet form, where the number form includes: and determining the serial number of each monitoring data, and sending the changed monitoring data to the upper computer in the form of serial number plus value. The grouping form comprises: dividing the plurality of monitoring data into a plurality of groups, wherein each group comprises a plurality of monitoring data, determining the group number of each group of monitoring data, and sending the group where the changed monitoring data is to the upper computer in the form of adding the numerical values of all members in the group by the group number.

In some embodiments, the sending the monitoring data to the upper computer through the communication module in step S102 includes:

step S201, determining the data sending mode according to the monitoring data, and sending the monitoring data to the upper computer through the communication module based on the data sending mode.

In some embodiments, the determining, according to the monitoring data, the data sending manner in step S201 includes: respectively calculating the number of bytes required by the monitoring data for transmitting the data in the number form and the grouping form, and selecting a data transmission mode with smaller number of bytes; the numbering form is selected in response to the same number of bytes required for both data transmission modes.

In a specific embodiment, the number and the group number of the data are both codes of one byte, and the numerical value is a code of two bytes; the grouping principle is that data is grouped according to the change condition of the data, the data which changes frequently is divided into a group, and the data which does not change is divided into a group (a sensitive value is set, and the real-time data is compared with the previous data, the change value is smaller than the sensitive value, and the real-time data is regarded as not changing). For example, three-phase current and voltage, 6 data are counted, and under the numbering form, each data has a numbering code of one byte and a numerical code of 2 bytes; in the packet form, a plurality of data shares a group number code of one byte, and each data has a numerical code of 2 bytes. For example, all data are divided into a "constant change" group and a "infrequent change" group, wherein the "constant change" group has 3 data in total, when only two data in all data are changed, if the data are sent in a number form, a code of 6 bytes is needed, if the data are sent in a grouping form, a code of 7 bytes is needed in the case that the two data are in one group, and a code of 14 bytes is needed in the case that the two data are in different groups; when only 3 data in the packet of "constant change" in all data are changed, if the data are transmitted in the form of numbers, a code of 9 bytes is required, and if the data are transmitted in the form of packets, a code of 7 bytes is required. Two data sending modes are set, and the two data sending modes are preferred according to the actual situation of each data sending, so that the communication efficiency can be improved, and the occupied communication resources can be saved.

When the communication module needs to send the heartbeat signal and the monitoring data at the same time, the monitoring data are sent preferentially. The heartbeat signal and the code of the monitoring data both comprise priority identification, the priority identification ensures that the monitoring data is sent in priority to the heartbeat signal, and the first-level alarm monitoring data is sent in priority to the second-level alarm monitoring data.

In view of the above, the present disclosure further provides a manual/automatic switching circuit and method. In some embodiments, as shown in fig. 3, the circuit monitoring system further includes a manual/automatic switching circuit, the manual/automatic switching circuit includes a manual control switch, an equipment start/stop switch, a normally open relay and a normally closed relay, a normally open contact of the three-phase motor is connected to an input end of the manual control switch, a common end of the three-phase motor is connected to a second output end of the normally closed relay, the input ends of the normally open relay and the normally closed relay are both connected to the I/O interface of the MCU module, a first output end of the normally open relay is connected to an OFF end of the manual control switch, a second output end of the normally open relay is connected to a first output end of the normally closed relay, and a first output end of the normally closed relay is further connected to an input end of the equipment start/stop switch, and the ON end of the equipment start-stop switch is connected with the ON end of the manual control switch. The normally open contact and the public end of the three-phase motor play the role of a motor switch. In specific implementation, the normally open relay and the normally closed relay are both magnetic latching relays HF 3F-L5-1 HL 1T, and the normally open function or the normally closed function is realized through different pin connection modes.

In some embodiments, the method further comprises: setting the manual control switch to an OFF state in response to a need for manually controlling operation of the three-phase motor; responding to the fact that the three-phase motor needs to be manually controlled to work while the MCU module monitors the three-phase current and the three-phase voltage, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by utilizing the equipment start-stop switch; and responding to the requirement of completely manually controlling the three-phase motor to work, cutting off the power supply of the MCU module, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by using the equipment start-stop switch. Under the condition of not cutting off the power supply of the MCU module, when the motor has a primary alarm fault during manual control, the MCU module can still control the motor to work, and even if the motor stops working, the safe operation of the motor is ensured.

In some embodiments, the method further comprises:

and S301, monitoring the temperature of the three-phase motor, the closing condition of a box door and the frequency output of a frequency converter by using the MCU module to obtain a plurality of auxiliary data.

And S302, sending the auxiliary data to the upper computer through the communication module, feeding back an auxiliary control signal to the MCU module by using the upper computer according to the auxiliary data, and controlling the three-phase motor to work by using the MCU module according to the auxiliary control signal.

The steps S301 and S302 are performed as an auxiliary monitoring function, and are mainly implemented by an I/O interface module of the system, where the I/O interface module is provided with a photoelectric isolator. The auxiliary monitoring considers the conditions that other conditions except three-phase current and three-phase voltage can cause motor faults and even production accidents, further avoids industrial production loss and ensures the safety of industrial production. And, above-mentioned supplementary monitoring function also all realizes through the MCU module, compares and uses different equipment to monitor above-mentioned condition among the prior art, has also practiced thrift equipment cost when guaranteeing three-phase motor's safe operation.

The I/O interface module includes a plurality of points: the temperature point location is connected with a temperature sensor and used for monitoring the cable temperature or the environment temperature of the motor; the door magnetic point position is used for monitoring the door closing condition of the motor distribution box; the frequency feedback point position is used for monitoring the actual frequency output of the motor frequency converter; the fault alarm point is connected with a frequency converter for alarm or a thermal relay for alarm.

In a specific embodiment, the step S302 includes: analyzing the auxiliary data by using the MCU module to obtain an auxiliary monitoring result, and determining an alarm level according to the auxiliary monitoring result; responding to the alarm level as a first-level alarm, and controlling the three-phase motor to work by using the MCU module; and responding to the alarm level as a secondary alarm, sending the auxiliary data to the upper computer through the communication module, feeding back an auxiliary control signal to the MCU module by using the upper computer according to the auxiliary data, and controlling the three-phase motor to work by using the MCU module according to the auxiliary control signal. In specific implementation, the monitoring of the temperature comprises: and the alarm and display functions can be used for measuring the temperature of a motor coil, the temperature of a cable or the ambient temperature. The temperature measurement value has 2 set values of high-temperature alarm, and the alarm or the reminding needs to be carried out when the temperature measurement value is higher than the set value. A high-temperature linkage protection is also arranged for the high temperature of the motor coil and the cable, and the high-temperature linkage protection is used for cutting off a power supply loop as the phase-lacking protection; monitoring of the frequency converter/relay includes: and (4) fault alarm: the device is used for alarming faults of a connection frequency converter, auxiliary contacts of a thermal relay or other equipment. When the alarm state changes, the alarm is processed in the same way as the alarm of the upper electric quantity measurement; the monitoring of the door sensor comprises the following steps: the passive input point is connected with a distribution box door magnetic switch and used for reminding when the box door is forgotten to be closed, and the alarm level is a reminding level.

In a specific embodiment, when the frequency converter exists in the motor, the MCU module performs PID parameter adjustment on the frequency-converted output through the I/O interface module to control the operation of the frequency converter.

It should be noted that the method of the embodiment of the present application may be executed by a single device, such as a computer or a server. The method of the embodiment can also be applied to a distributed scene and completed by the mutual cooperation of a plurality of devices. In such a distributed scenario, one of the multiple devices may only perform one or more steps of the method of the embodiment, and the multiple devices interact with each other to complete the method.

It should be noted that the foregoing describes some embodiments of the present application. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments described above and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may also be possible or may be advantageous.

Based on the same inventive concept, corresponding to the method of any of the above embodiments, the present application further provides a circuit monitoring device based on a three-phase motor, as shown in fig. 4, the device is implemented by using a circuit monitoring system, the circuit monitoring system includes an MCU module, a communication module, and an upper computer, the device includes:

the monitoring module 10 is configured to monitor the three-phase current and the three-phase voltage of the three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyze the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determine an alarm level according to the monitoring result.

And a primary alarm response module 20 configured to control the three-phase motor to operate by using the MCU module in response to the alarm level being a primary alarm.

And the secondary alarm response module 30 is configured to respond that the alarm level is a secondary alarm, send the monitoring data to the upper computer through the communication module, utilize the upper computer to feed back a control signal to the MCU module according to the monitoring data, and utilize the MCU module to control the three-phase motor to work according to the control signal.

The device that this application embodiment provided can carry out real time monitoring to three-phase motor's current-voltage parameter and provide three-phase motor's real-time working data to the host computer, can judge three-phase motor's real-time working condition through single equipment to in time discover three-phase motor's working data is unusual, guaranteed three-phase motor's safe operation when practicing thrift equipment cost.

In some embodiments, the alarm levels include a zero level alarm, a first level alarm, and the second level alarm; the monitoring module is further configured to: determining the alarm level as a zero-level alarm in response to not including any abnormal value in the monitoring result; determining the alarm level as a primary alarm in response to the monitoring results including voltage/current phase loss, motor stalling/blocking, circuit short circuit, voltage lower than an undervoltage threshold, voltage higher than an overvoltage threshold, current higher than an overload threshold, and current peak pulse frequency higher than a pulse threshold, wherein the undervoltage threshold, the overvoltage threshold, the overload threshold, and the pulse threshold are all preset; determining the alarm level as a secondary alarm in response to the monitoring result including an abnormal value but not including a voltage/current phase loss, a motor stalling/encountering resistance, a circuit short, a voltage below the undervoltage threshold, a voltage above the overvoltage threshold, a current above the overload threshold, and a current peak pulse frequency above the pulse threshold.

In some embodiments, the primary alarm response module is further configured to: and responding to the first-level alarm of the alarm level, stopping the three-phase motor by using the MCU module, and sending the monitoring data to the upper computer through the communication module.

In some embodiments, when the primary alarm response module and the secondary alarm response module send the monitoring data to the upper computer through the communication module, the data sending mode of the monitoring data includes a number form and a grouping form, and the number form includes: and determining the serial number of each monitoring data, and sending the changed monitoring data to the upper computer in the form of serial number plus value. The grouping form comprises: dividing the plurality of monitoring data into a plurality of groups, wherein each group comprises a plurality of monitoring data, determining the group number of each group of monitoring data, and sending the group where the changed monitoring data is to the upper computer in the form of adding the numerical values of all members in the group by the group number.

In some embodiments, the primary and secondary alarm response modules are further configured to: and determining the data sending mode according to the monitoring data, and sending the monitoring data to the upper computer through the communication module based on the data sending mode.

In some embodiments, the primary and secondary alarm response modules are further configured to: respectively calculating the number of bytes required by the monitoring data for transmitting the data in the number form and the grouping form, and selecting a data transmission mode with smaller number of bytes; the numbering form is selected in response to the same number of bytes required for both data transmission modes.

In some embodiments, the circuit monitoring system further comprises a manual/automatic switching circuit, the manual/automatic switching circuit comprises a manual control switch, an equipment start-stop switch, a normally open relay and a normally closed relay, the normally open contact of the three-phase motor is connected with the input end of the manual control switch, the common end of the three-phase motor is connected with the second output end of the normally closed relay, the input ends of the normally open relay and the normally closed relay are both connected with the MCU module, the first output end of the normally open relay is connected with the OFF end of the manual control switch, the second output end of the normally open relay is connected with the first output end of the normally closed relay, the first output end of the normally closed relay is further connected with the input end of the equipment start-stop switch, and the ON end of the equipment start-stop switch is connected with the ON end of the manual control switch.

In some embodiments, the apparatus further comprises:

a manual/automatic switching module configured to set the manual control switch to an OFF state in response to a need for manual control of operation of the three-phase motor; responding to the fact that the three-phase motor needs to be manually controlled to work while the MCU module monitors the three-phase current and the three-phase voltage, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by utilizing the equipment start-stop switch; and responding to the requirement of completely manually controlling the three-phase motor to work, cutting off the power supply of the MCU module, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by using the equipment start-stop switch.

In some embodiments, the apparatus further comprises:

and the auxiliary monitoring module is configured to monitor the temperature of the three-phase motor, the closing condition of the box door and the frequency output of the frequency converter by utilizing the MCU module to obtain a plurality of auxiliary data.

And the auxiliary control module is configured to send the auxiliary data to the upper computer through the communication module, feed back an auxiliary control signal to the MCU module by using the upper computer according to the auxiliary data, and control the three-phase motor to work by using the MCU module according to the auxiliary control signal.

For convenience of description, the above devices are described as being divided into various modules by functions, and are described separately. Of course, the functionality of the various modules may be implemented in the same one or more software and/or hardware implementations as the present application.

The device of the above embodiment is used to implement the corresponding circuit monitoring method based on the three-phase motor in any of the foregoing embodiments, and has the beneficial effects of the corresponding method embodiment, which are not described herein again.

Based on the same inventive concept, corresponding to the method of any embodiment described above, the present application further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the program, the method for monitoring a circuit based on a three-phase motor according to any embodiment described above is implemented.

Fig. 5 is a schematic diagram illustrating a more specific hardware structure of an electronic device according to this embodiment, where the electronic device may include: a processor 510, a memory 520, an input/output interface 530, a communication interface 540, and a bus 550. Wherein processor 510, memory 520, input/output interface 530, and communication interface 540 are communicatively coupled to each other within the device via bus 550.

The processor 510 may be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an Application Specific Integrated Circuit (ASIC), or one or more Integrated circuits, and is configured to execute related programs to implement the technical solutions provided in the embodiments of the present specification.

The Memory 520 may be implemented in the form of a ROM (Read Only Memory), a RAM (Random Access Memory), a static storage device, a dynamic storage device, or the like. The memory 520 may store an operating system and other application programs, and when the technical solution provided by the embodiments of the present specification is implemented by software or firmware, the relevant program codes are stored in the memory 520 and called by the processor 510 for execution.

The input/output interface 530 is used for connecting an input/output module to realize information input and output. The i/o module may be configured as a component within the device (not shown) or may be external to the device to provide corresponding functionality. Wherein the input devices may include a keyboard, mouse, touch screen, microphone, various sensors, etc., and the output devices may include a display, speaker, vibrator, indicator light, etc.

The communication interface 540 is used for connecting a communication module (not shown in the figure) to realize communication interaction between the device and other devices. The communication module can realize communication in a wired mode (such as USB, network cable and the like) and also can realize communication in a wireless mode (such as mobile network, WIFI, Bluetooth and the like).

Bus 550 includes a pathway to transfer information between various components of the device, such as processor 510, memory 520, input/output interface 530, and communication interface 540.

It should be noted that although the above-mentioned device only shows the processor 510, the memory 520, the input/output interface 530, the communication interface 540 and the bus 550, in a specific implementation, the device may also include other components necessary for normal operation. In addition, those skilled in the art will appreciate that the above-described apparatus may also include only those components necessary to implement the embodiments of the present description, and not necessarily all of the components shown in the figures.

The electronic device of the above embodiment is used to implement the corresponding circuit monitoring method based on the three-phase motor in any of the foregoing embodiments, and has the beneficial effects of the corresponding method embodiment, which are not described herein again.

Based on the same inventive concept, corresponding to any of the above-described embodiment methods, the present application also provides a non-transitory computer-readable storage medium storing computer instructions for causing the computer to perform the three-phase motor-based circuit monitoring method according to any of the above-described embodiments.

Computer-readable media of the present embodiments, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device.

The computer instructions stored in the storage medium of the above embodiment are used to enable the computer to execute the circuit monitoring method based on the three-phase motor according to any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which are not described herein again.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the context of the present application, technical features in the above embodiments or in different embodiments may also be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application described above, which are not provided in detail for the sake of brevity.

In addition, well-known power/ground connections to Integrated Circuit (IC) chips and other components may or may not be shown in the provided figures for simplicity of illustration and discussion, and so as not to obscure the embodiments of the application. Furthermore, devices may be shown in block diagram form in order to avoid obscuring embodiments of the application, and this also takes into account the fact that specifics with respect to implementation of such block diagram devices are highly dependent upon the platform within which the embodiments of the application are to be implemented (i.e., specifics should be well within purview of one skilled in the art). Where specific details (e.g., circuits) are set forth in order to describe example embodiments of the application, it should be apparent to one skilled in the art that the embodiments of the application can be practiced without, or with variation of, these specific details. Accordingly, the description is to be regarded as illustrative instead of restrictive.

While the present application has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art in light of the foregoing description. For example, other memory architectures (e.g., dynamic ram (dram)) may use the discussed embodiments.

The present embodiments are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omissions, modifications, substitutions, improvements, and the like that may be made without departing from the spirit and principles of the embodiments of the present application are intended to be included within the scope of the present application.

Claims

1. A circuit monitoring method based on a three-phase motor is characterized in that the method is implemented by using a circuit monitoring system, the circuit monitoring system comprises an MCU module, a communication module and an upper computer, and the method comprises the following steps:

monitoring three-phase current and three-phase voltage of a three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyzing the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determining an alarm level according to the monitoring result;

responding to the alarm level as a first-level alarm, and controlling the three-phase motor to work by using the MCU module;

and responding to the fact that the alarm level is a secondary alarm, sending the monitoring data to the upper computer through the communication module, feeding back a control signal to the MCU module by using the upper computer according to the monitoring data, and controlling the three-phase motor to work by using the MCU module according to the control signal.

2. The method of claim 1, wherein the alarm levels include a zero level alarm, a first level alarm, and the second level alarm; the determining an alarm level according to the monitoring result comprises:

determining the alarm level as a zero-level alarm in response to not including any abnormal value in the monitoring result;

determining the alarm level as a primary alarm in response to the monitoring results including voltage/current phase loss, motor stalling/blocking, circuit short circuit, voltage lower than an undervoltage threshold, voltage higher than an overvoltage threshold, current higher than an overload threshold, and current peak pulse frequency higher than a pulse threshold, wherein the undervoltage threshold, the overvoltage threshold, the overload threshold, and the pulse threshold are all preset;

determining the alarm level as a secondary alarm in response to the monitoring result including an abnormal value but not including a voltage/current phase loss, a motor stalling/encountering resistance, a circuit short, a voltage below the undervoltage threshold, a voltage above the overvoltage threshold, a current above the overload threshold, and a current peak pulse frequency above the pulse threshold.

3. The circuit monitoring method based on the three-phase motor according to claim 1, wherein the controlling the three-phase motor to operate by the MCU module in response to the alarm level being a primary alarm comprises:

and responding to the first-level alarm of the alarm level, stopping the three-phase motor by using the MCU module, and sending the monitoring data to the upper computer through the communication module.

4. The circuit monitoring method based on the three-phase motor according to claim 1, wherein when the monitoring data is sent to the upper computer through the communication module, the data sending mode of the monitoring data includes a number form and a grouping form, and the number form includes: determining the serial number of each monitoring data, and sending the changed monitoring data to the upper computer in the form of serial number plus value;

the grouping form comprises: dividing the monitoring data into a plurality of groups, wherein each group comprises a plurality of monitoring data, determining the group number of each group of monitoring data, and sending the group in which the changed monitoring data is positioned to the upper computer in the form of adding the numerical values of all members in the group by the group number;

the monitoring data is sent to the upper computer through the communication module, and the monitoring data sending method comprises the following steps:

and determining the data sending mode according to the monitoring data, and sending the monitoring data to the upper computer through the communication module based on the data sending mode.

5. The circuit monitoring method based on the three-phase motor according to claim 4, wherein the determining the data transmission mode according to the monitoring data comprises:

respectively calculating the number of bytes required by the monitoring data for transmitting the data in the number form and the grouping form, and selecting a data transmission mode with smaller number of bytes; the number format is selected in response to the same number of bytes required for both data transmission modes.

6. The circuit monitoring method based on the three-phase motor according to claim 1, wherein the circuit monitoring system further comprises a manual/automatic switching circuit, the manual/automatic switching circuit comprises a manual control switch, a device start/stop switch, a normally open relay and a normally closed relay, a normally open contact of the three-phase motor is connected with an input end of the manual control switch, a common end of the three-phase motor is connected with a second output end of the normally closed relay, the input ends of the normally open relay and the normally closed relay are both connected with the MCU module, a first output end of the normally open relay is connected with an OFF end of the manual control switch, a second output end of the normally open relay is connected with a first output end of the normally closed relay, and a first output end of the normally closed relay is further connected with an input end of the device start/stop switch, the ON end of the equipment start-stop switch is connected with the ON end of the manual control switch;

the method further comprises the following steps:

setting the manual control switch to an OFF state in response to a need for manually controlling operation of the three-phase motor;

responding to the fact that the three-phase motor needs to be manually controlled to work while the MCU module monitors the three-phase current and the three-phase voltage, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by utilizing the equipment start-stop switch;

and responding to the requirement of completely manually controlling the three-phase motor to work, cutting off the power supply of the MCU module, setting the manual control switch to be in an ON state, and controlling the three-phase motor to work by using the equipment start-stop switch.

7. The method of circuit monitoring based on a three-phase electric machine according to claim 1, further comprising:

monitoring the temperature of the three-phase motor, the closing condition of a box door and the frequency output of a frequency converter by using the MCU module to obtain a plurality of auxiliary data;

and sending the auxiliary data to the upper computer through the communication module, feeding back an auxiliary control signal to the MCU module by using the upper computer according to the auxiliary data, and controlling the three-phase motor to work by using the MCU module according to the auxiliary control signal.

8. The utility model provides a circuit monitoring device based on three-phase motor, its characterized in that, the device utilizes circuit monitoring system to implement, circuit monitoring system includes MCU module, communication module and host computer, the device includes:

the monitoring module is configured to monitor three-phase current and three-phase voltage of the three-phase motor by using the MCU module to obtain a plurality of monitoring data, analyze the plurality of monitoring data by using the MCU module to obtain a monitoring result, and determine an alarm level according to the monitoring result;

the primary alarm response module is configured to respond to the alarm level being primary alarm and control the three-phase motor to work by the MCU module;

and the secondary alarm response module is configured to respond to the alarm level being a secondary alarm, send the monitoring data to the upper computer through the communication module, utilize the upper computer to feed back a control signal to the MCU module according to the monitoring data, and utilize the MCU module to control the three-phase motor to work according to the control signal.

9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the method according to any of claims 1 to 7 when executing the program.

10. A non-transitory computer readable storage medium storing computer instructions for causing a computer to perform the method of any one of claims 1 to 7.