Healthy diagnosis and protection method for high-speed sampling of tunneling equipment and electric control system thereof

Abstract

The invention discloses a tunneling equipment high-speed sampling health diagnosis and protection method and an electric control system thereof, and relates to the field of tunneling equipment electric control systems, and the tunneling equipment high-speed sampling health diagnosis and protection method comprises a multi-loop three-phase current transformer, a common-bus three-phase voltage transformer, a high-speed sampler, a processing analyzer, a transmitter, an embedded industrial personal computer and an electric component formed by a controller. By high-speed acquisition and processing of original multi-electric-quantity signals, a traditional electric control system electric quantity sampling analysis mode is replaced, fault pre-warning, fault post-protection and original electric quantity information real-time storage are realized, online advanced pre-warning and protection are realized, offline analysis of high-speed sampled original large-capacity data is realized, functions of a small oscilloscope are integrated, and the system is simple in structure and convenient to use. The tunneling equipment electric control system is innovated, and the tunneling equipment electric control system has new functions of key transmission part degradation condition prediction, power supply network harmonic content analysis, ultra-high-speed original signal sampling, large-capacity data real-time transmission and storage and the like.

Description

Technical Field

[0001] This invention relates to the field of electrical control systems for tunneling equipment, specifically to a high-speed sampling health diagnosis and protection method for tunneling equipment and its electrical control system. Background Technology

[0002] Tunneling equipment is a core component in underground engineering projects such as mines and tunnels, and its operational stability directly determines project progress and construction safety. With increasing underground mining depth and complexity, tunneling equipment needs to drive multiple types of loads (such as hydraulic system pumps, coal cutting mechanisms, rake systems, conveying systems, and dust removal equipment) continuously, and these loads generally have high power (e.g., 1140V high-voltage motor loads). The electrical control system of this equipment, acting as its "central nervous system," must monitor the operating status of each load in real time, calculate key electrical parameters, and execute fault protection actions to prevent equipment damage or safety accidents caused by abnormal loads. It is the core support for ensuring the continuous and efficient operation of tunneling equipment.

[0003] Existing tunneling equipment electrical control systems primarily rely on multi-loop current sensors and common bus voltage sensors to collect electrical signals. The controller calculates the RMS current, RMS voltage, and power factor of each drive loop, then compares the calculated values ​​with the load's rated values ​​to protect against faults such as short circuits, phase loss, and overloads. The electrical parameter calculations are based on the fundamental frequency, with a period of at least one cycle (20ms). The sampled data undergoes digital or hardware filtering to output an averaged result reflecting stable load changes. Protection actions are set based on the ratio of actual current to set current and the load's initial state (cold / hot). For example, in overload protection, when the actual current is 1.2 times the set current (hot state), the action time is controlled between 1-3 minutes. For short circuit faults, different reset methods are triggered based on the current multiple.

[0004] Existing electrical control systems for tunneling equipment have significant technical deficiencies, making it difficult to meet the requirements for precise protection and early warning under complex working conditions:

[0005] First, the protection mode is "post-event protection", which can only trigger the protection action after the equipment or load has failed (such as short circuit, overload) or is not operating normally. It cannot identify potential faults in advance, which causes irreversible damage to the equipment transmission components (such as motors and reducers) due to the impact of the fault, shortening their service life.

[0006] Second, the response speed is slow. Since the calculation of electrical parameters needs to be based on steady-state data of at least one cycle, and the filtering process further increases the delay, the time for the electrical control system to issue protection signals is usually around 100ms. It cannot respond in time to instantaneous faults such as short circuits, which can easily cause secondary damage to electrical components (such as transformers and contactors).

[0007] Third, it cannot identify transient and deterioration states. Existing systems only process the steady-state part of electrical signals and cannot collect or analyze transient signals (such as current fluctuations during motor startup and harmonics generated by nonlinear loads). It cannot accurately determine faults during startup (analysis can only be performed after avoiding the startup current), nor can it identify the deterioration trend of key components of the equipment (such as subtle changes in current caused by bearing wear and tooth wear), and it cannot reconstruct the fault scene to trace the cause of the fault.

[0008] Fourth, power quality and harmonic analysis are lacking. The existing system does not monitor the power supply quality, harmonics caused by nonlinear loads, and electromagnetic radiation, making it difficult to identify transient faults caused by waveform distortion and harmonic interference, which further reduces the accuracy and comprehensiveness of protection.

[0009] Fifth, the lack of large-capacity data storage makes subsequent equipment diagnosis and protection analysis inconvenient. Summary of the Invention

[0010] Based on this, the purpose of the present invention is to provide a high-speed sampling health diagnosis and protection method for tunneling equipment and its electrical control system, so as to solve the technical problems mentioned in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: an electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment, comprising a multi-loop three-phase current transformer, a common bus three-phase voltage transformer, a processor and analyzer, a transmitter and a controller, wherein the controller is used to perform control of various actuators of the tunneling equipment, sensor information processing, status signal interaction, operation mode signal processing and human-machine interaction data transmission, characterized in that it further comprises a high-speed processor and an embedded industrial control computer;

[0012] The high-speed sampling module completes wide-range, multi-variable power synchronous sampling; the processing and analysis module completes the instantaneous value, effective value, power factor, and harmonic content of the actual electrical signal; the transmission module completes the real-time transmission of large-capacity data; the micro industrial computer stores the data; the controller receives the electrical signal analysis results and completes the functions of driving, executing, and displaying; at the same time, the high-speed processor calculates multiple harmonics and evaluates and analyzes the power quality and nonlinear load.

[0013] The high-speed processor is connected to the multi-loop three-phase current transformer and the common bus three-phase voltage transformer, and is used to synchronously acquire the original secondary current signal and the original secondary voltage signal of the power supply bus of each loop with different load categories in real time at a sampling frequency of 50 microseconds. The high-speed processor has multiple A / D conversion devices embedded in it. Each A / D conversion device has an independent sampling loop. Each load loop occupies one A / D channel. The A, B, and C phases of the same loop are converted by A / D in a time-sharing manner through a high-speed electronic conversion switch. The three-phase power supply voltage shares one A / D channel. The high-speed processor aligns and integrates the data from different current and voltage sensors in time or space to realize synchronous and same-frequency sampling of multi-loop current and bus voltage.

[0014] The high-speed processor is also used to calculate the acquired raw signal using the short-time Fourier algorithm and wavelet transform to obtain the effective values ​​of current, voltage, phase angle, and harmonics of each loop; and to calculate the upper half-wave value within the full cycle based on the load rated current I. Compared with the calculated value of the second half wave The average value determines the actual operating current. The effective values ​​of the current and voltage are transmitted to the controller for traditional electrical protection.

[0015] The high-speed processor is communicatively connected to the embedded industrial control computer and is used to transmit the packaged original electrical signals to the embedded industrial control computer. The embedded industrial control computer is used to store the original electrical signals and classify and store data according to the load categories of hydraulic system oil pump load, coal cutting system cutting load, rake claw system loading load, conveying system transport load, and dust removal load, combined with the phases A, B, and C and the time sequence. The embedded industrial control computer is also used to interact with the high-speed processor via FTP protocol and to realize offline data retrieval via USB interface or external wireless communication interface.

[0016] The embedded industrial control computer is also used for online diagnosis: classifying and analyzing current data according to the load characteristics of stable hydraulic oil pump load, heavy-duty cutting load, and frequently starting load; using different algorithms according to the type of signal anomaly caused by electrical / mechanical and the symmetrical / asymmetrical anomaly, to determine three-phase short circuit, two-phase short circuit, and asynchronous or jammed faults in motor connection equipment.

[0017] The controller is used to execute protection strategies: combining faults With fault prediction Fault prediction rate is measured using a 1-day work cycle. When two consecutive work cycles When the operating condition stability index is greater than 90% and the actual operating current is ≥95%, an intermittent protection signal is issued, initially with a 10-minute shutdown and lockout per day. The operating condition stability index is the percentage of the actual operating current that is less than the rated current in the previous working cycle. When the stability exceeds 95%, the protection lockout shutdown time is calculated according to the formula. Calculation; protection signal It is used to drive the load to stop.

[0018] The A / D conversion logic of the high-speed processor is as follows: Phase A, Phase B, and Phase C of the same load circuit are sequentially connected to the corresponding A / D channel of the circuit through a high-speed electronic conversion switch. The three-phase power supply voltage is fixedly connected to a dedicated A / D channel. Data from different current and voltage sensors are aligned and integrated in time or space to ensure the accuracy of power factor calculation for each circuit.

[0019] By monitoring power factor, current amplitude, and operating conditions in real time, load protection can be implemented according to different working periods and areas. Different working periods and areas are distinguished by power factor and load characteristics, enabling more reliable protection. This method shifts from time-delay and current amplitude protection to a combination of power factor and current analysis. Monitoring the power factor provides a basis for assessing the compatibility between the designed power rating and the actual load, and also provides data samples for subsequent design and selection.

[0020] The high-speed processor determines the actual operating current. The specific logic is as follows:

[0021] If the calculated value of the first half of the first full cycle Compared with the calculated value of the second half wave If the difference is less than 0.5I, then ;

[0022] like and The difference is greater than 0.5 Then the calculated value of the first half of the second full cycle will be... and In comparison, if and If the difference is ≤0.5I, then And so on;

[0023] Through the above logic, the high-speed processor controls the electrical short-circuit protection fault time to within 10ms.

[0024] The classification and storage logic of the embedded industrial control computer is as follows:

[0025] Create first-level folders based on load categories, corresponding to hydraulic oil pump loads, cutting loads, loading loads, transportation loads, and dust removal loads respectively;

[0026] Each first-level folder contains second-level subfolders categorized as Phase A, Phase B, and Phase C.

[0027] Each second-level subfolder is divided into several storage files in chronological order, and the file splitting period matches the sampling data capacity requirements;

[0028] The wireless communication interface supports setting the data extraction category, time range, and file size to achieve accurate extraction of fault data.

[0029] The fault diagnosis logic of the embedded industrial control computer is as follows:

[0030] Three-phase short circuit detection: If the instantaneous currents of phases A, B, and C, after the phase crossing zero point, accumulate to more than 25% of the rated load current over one sampling period, then the short circuit criterion is met. When the value is 8 times the value, it is determined to be a three-phase short circuit;

[0031] Two-phase short circuit determination: The negative sequence current formed by the instantaneous currents of any two phases (A, B, and C) after the phase zero-crossing point accumulates to more than 25% of the total current over one sampling period. When the value is 2.5 times the value, it is determined to be a two-phase short circuit;

[0032] Motor and connected equipment fault diagnosis: If the instantaneous current shows a regular increase within one current cycle during the rotation of the motor and connected equipment, it is determined to be a fault of equipment asynchrony or jamming.

[0033] The controller's protection strategy also includes: if within a single working cycle If the failure rate is ≥80%, the fault prediction for that cycle is considered valid; if the failure rate is ≥80% in the next work cycle, the fault prediction is considered valid. The controller does not issue a warning shutdown signal when the temperature drops; it only does so when two consecutive operating cycles meet the requirements. Intermittent protection signals are triggered only when the operating condition stability index is greater than 90% and the operating condition stability index is greater than 95%.

[0034] 7. A method for high-speed sampling health diagnosis and protection of tunneling equipment, characterized by comprising the following steps:

[0035] S1: High-speed synchronous sampling

[0036] The high-speed processor synchronously acquires the original current signals of the secondary side of multi-loop three-phase current transformers and the original voltage signals of the secondary side of three-phase voltage transformers with a common bus at a sampling frequency of 50 microseconds. The high-speed processor allocates sampling channels by using multiple embedded independent A / D conversion devices, with one A / D channel for one loop and one A / D channel for three-phase voltage. The A / B / C phases of the same loop are sampled in a time-division manner through high-speed electronic conversion switches, and the original sampled values ​​marked with time windows are established to ensure sampling synchronization.

[0037] S2: Raw Signal Processing

[0038] The high-speed processor uses the short-time Fourier transform algorithm and wavelet transform to calculate the acquired raw signal, obtaining the effective values ​​of current and voltage, phase angle, and harmonics of each circuit; using the rated current I as a reference, it calculates the upper half-wave value within the full cycle. Compared with the calculated value of the second half wave The difference is used to determine the actual operating current I. S The effective values ​​of the current and voltage are transmitted to the controller, and the packaged original power signal is transmitted to the embedded industrial computer.

[0039] S3: Data Storage and Retrieval

[0040] The embedded industrial computer stores the original power signals according to load type, phase, and time sequence; it receives high-speed processor data via FTP protocol and realizes offline data extraction via USB interface or wireless communication interface.

[0041] S4: Online Health Diagnosis

[0042] The embedded industrial control computer analyzes current data according to load characteristics, and uses different algorithms according to electrical / mechanical abnormality type and symmetrical / asymmetrical abnormality to determine three-phase short circuit, two-phase short circuit and motor connection equipment fault;

[0043] S5: Protection and Early Warning Execution

[0044] The controller combines fault With fault prediction Testing is conducted on a 1-day work cycle. When two consecutive work cycles When the efficiency is ≥95% and the operating condition stability index is greater than 90%, an intermittent protection signal is issued; When the stability exceeds 95%, according to Calculate the protection time; use the protection signal Drive load shutdown.

[0045] In step S1, the sampling synchronization control logic of the high-speed processor is as follows: based on the time window, ensure that the sampling of all loop current signals and bus voltage signals is completed within the same time window, and the time-division sampling interval of phases A / B / C of the same loop does not affect the power factor calculation accuracy.

[0046] In step S4, the specific basis for fault judgment is as follows:

[0047] Three-phase short circuit: After the instantaneous current of phases A / B / C crosses zero, the cumulative current exceeding 25% of one sampling period exceeds 8I. e ;

[0048] Two-phase short circuit: When the negative sequence currents of any two phases accumulate to more than 25% of the total current over one sampling period after the phase crosses zero, exceeding 2.5I. e ;

[0049] Motor fault: The instantaneous current increases regularly within one current cycle.

[0050] A method for high-speed sampling health diagnosis and protection of tunneling equipment, further comprising a feedback control current selection step:

[0051] Set a cycle division coefficient k according to the load type, and take k=2, 4, 6, 8;

[0052] The number of sampling points i = 20 × 1000 / T for one cycle is calculated based on the sampling period T. The number of sampling points i used for feedback calculation is then determined. j =i / k;

[0053] An improved Fourier algorithm is used to calculate the instantaneous average current of the k-th wave, and this average value is used as the feedback current for load speed control.

[0054] In summary, the present invention has the following main advantages: It acquires raw electrical signals using a high-speed processor and combines this with an embedded industrial control computer online diagnostic algorithm to achieve dual protection against faults, including pre-fault warning and post-fault protection. This allows for early identification of component degradation trends and triggering intermittent warning shutdowns, while also controlling the protection time for transient faults such as short circuits within 30ms, extending the service life of critical components and reducing downtime without faults. Furthermore, relying on high-speed synchronous sampling and a short-time Fourier algorithm, it accurately acquires the effective values ​​of current / voltage, phase angle, and harmonic data, enabling analysis of power quality and nonlinear load harmonics, improving fault identification accuracy, and solving the problem of traditional systems being unable to handle transient signals. Attached Figure Description

[0055] Figure 1 This is a functional diagram of the electrical control box controller of the present invention;

[0056] Figure 2 This is a flowchart illustrating the structure and data transmission of the electronic control system of the present invention.

[0057] Figure 3 This is a flowchart of the data extraction process of the present invention. Detailed Implementation

[0058] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0059] The embodiments of the present invention will now be described.

[0060] A high-speed sampling health diagnosis and protection electrical control system for tunneling equipment mainly includes: multi-circuit three-phase current transformers, common bus three-phase voltage transformers, traditional controllers, high-speed processors, and embedded industrial control computers. The connection relationships and core functions of each component are as follows:

[0061] Multi-circuit three-phase current transformers: a total of 5 sets are set up, corresponding to the hydraulic system oil pump load of the tunneling equipment, the cutting load of the coal cutting system, the loading load of the rake claw system, the transportation load of the conveying system, and the dust removal load. The secondary side of each set of transformers is connected to the signal input terminal of the high-speed processor to collect the original current signal of each load circuit.

[0062] Common bus three-phase voltage transformer: The secondary side is connected to the dedicated voltage sampling terminal of the high-speed processor to collect the original voltage signal of the 1140V power supply bus.

[0063] Traditional controller: It adopts a PLC controller, which communicates with a high-speed processor via RS485 bus. It also connects to the actuators of the tunneling equipment, such as motors and valves, as well as the operation panel and status indicator lights, to realize traditional control, such as start / stop, speed adjustment, protection signal execution, and human-machine interaction.

[0064] High-speed processor: It adopts a DSP chip and has an embedded 8-channel independent A / D conversion device. The sampling frequency is set to 50 microseconds. It is connected to the current transformer, voltage transformer and embedded industrial control computer through analog signal lines and Ethernet respectively. Its core functions are high-speed sampling, signal calculation and data transmission.

[0065] Embedded industrial computer: It adopts an industrial-grade embedded computer, which exchanges data with a high-speed processor via FTP protocol, connects to mobile storage devices via USB 3.0 interface, and communicates with mobile APP via WiFi module to realize data storage, online diagnosis and offline retrieval.

[0066] The high-speed processor's 8-channel A / D converter allocates channels according to the following rules: each of the 5 load circuits occupies 1 A / D channel; the A-phase, B-phase, and C-phase current signals of the same circuit are accessed to the channel in a time-sharing manner through a high-speed electronic switching switch. The switching time of the switching switch is less than 1 microsecond, ensuring that the sampling interval of the three-phase signals of the same circuit does not affect the phase calculation accuracy.

[0067] One dedicated A / D channel for acquiring three-phase power supply voltage: Phase A, B, and C voltage signals are accessed in a time-sharing manner through the same transfer switch. The sampling synchronization with the current signal is achieved through time window marking. A timestamp is generated every 50 microseconds, and all sampled signals are bound to this timestamp for storage, ensuring that the current and voltage signals within the same time window are synchronously acquired data, thereby ensuring the accuracy of power factor calculation. The power factor is cosφ, where φ is the phase difference between current and voltage. Synchronous sampling can make the calculation error of φ ≤0.5°.

[0068] The high-speed processor uses the Short Time Fourier Transform algorithm to calculate the original sampled signal. The specific steps are as follows:

[0069] Half-wave signal extraction: The original signal with a fundamental frequency period of 20ms is divided into an upper half-wave (0-10ms) and a lower half-wave (10-20ms), and the effective value I of the upper half-wave is calculated separately. Z and the RMS value of the lower half-wave I F

[0070] The Fourier algorithm formula is: Where N is the number of half-wave sampling points, i k Let be the instantaneous current value at the k-th sampling point;

[0071] Actual operating current I S Judgment: Based on the rated load current I, such as the rated current of the cutting motor I = 100A, I is determined according to the following logic. S :

[0072] If the calculated value of the first half of the first full cycle Compared with the calculated value of the second half wave If the difference is less than 0.5I, i.e. 50A, then For example: I Z1 =102A, I F1 =98A, difference 4A≤50A, I S =(102+98) / 2=100A.

[0073] If I Z1 with I F1 The difference is greater than 0.5I (e.g., I). Z1 =160A, I F1 =100A, difference 60A>50A), then take the upper half of the second full cycle I. Z2 with I F1 Comparison: If I Z2 =105A, and I F1 If the difference is 5A ≤ 50A, then I S =(105+100) / 2=102.5A.

[0074] Through the above logic, the fault response time of electrical short circuit protection can be controlled within 10ms, while the traditional system requires more than 100ms, thus avoiding secondary damage to electrical components;

[0075] Harmonic and phase angle calculation: The original signal is decomposed by short-time Fourier algorithm, and the amplitude and phase of the 2nd to 50th harmonics can be extracted, such as the 3rd harmonic and the 5th harmonic. At the same time, the phase angle of the current and voltage of each circuit is calculated. For example, the phase angle of the hydraulic oil pump load is about -30°, indicating that the load is inductive. The phase angle data is used to distinguish subsequent working conditions. If the phase angle changes abruptly, it may correspond to load jamming.

[0076] The solid-state drives embedded in the industrial control computer store data in a three-level directory structure based on load type, phase, and time, as detailed below:

[0077] First-level directory (load category): Create 5 folders named "Hydraulic oil pump load", "Cutting load", "Loading load", "Transportation load" and "Dust removal load", which correspond to the sampling data of 5 load circuits respectively.

[0078] Second-level directories (phases): Each first-level directory contains 3 subfolders named A-phase, B-phase, and C-phase, which store the original current and voltage signals of the corresponding phases.

[0079] Third-level directory (time): Files in each second-level directory are split by hour.

[0080] Specific implementation of data extraction methods:

[0081] Offline extraction: After connecting a USB flash drive via the USB interface and the industrial control computer automatically recognizes the device, the user can select the load type, phase, and time range through the industrial control computer's touch screen to export the corresponding file.

[0082] Wireless extraction: A mobile app, supporting Android / iOS systems, connects to the industrial control computer via WiFi. Users can set "data category", "time range" and "file size" in the app interface. After receiving the request, the industrial control computer compresses the data into ZIP format and sends it to the app, enabling remote and accurate extraction of fault data.

[0083] The embedded industrial control computer implements online diagnostics based on a two-dimensional logic that categorizes load characteristics and anomaly types, as detailed below:

[0084] Load characteristic classification: The five loads are divided into three categories, and different diagnostic algorithms are used:

[0085] For stable loads, such as hydraulic pumps and dust collectors: focus on monitoring the current fluctuation amplitude; normal fluctuation should be less than 5%. e I e For the rated current, if the fluctuation amplitude is greater than 10%I for 10 consecutive cycles. eThe cause was determined to be a leak in the hydraulic system or ash blockage in the fan.

[0086] For heavy-load loads, such as truncated loads: focus on monitoring the peak current; the normal peak current should be less than 2I. e If the peak value is greater than 3I e If this continues for two cycles, it is determined to be either "cutting tooth wear" or "overload when cutting hard rock".

[0087] For loads that frequently start, such as loading and transportation: focus on monitoring the rate of start-up current decay. Within one second of normal startup, the current should decrease from 6I... e Reduced to 2I e If the decay rate is less than 5I e / second, determined to be a speed reducer jamming.

[0088] Fault type determination based on instantaneous current characteristics:

[0089] Three-phase short circuit detection: Collect the instantaneous current of phases A, B, and C. After the phase crosses zero (i.e., the current changes from negative to positive), count the instantaneous current value within a 50-microsecond sampling period. If the cumulative value exceeds 25%, i.e., the instantaneous current within 12.5 microseconds is greater than 8I... e , such as I e =50A, 8I e =400A, then it is determined to be a three-phase short circuit, and a fault signal F is immediately sent to the controller. f .

[0090] Two-phase short circuit detection: Calculate the negative sequence current of any two phases, such as phase A and phase B. The negative sequence current is... ,in For a complex operator, after the phase crosses zero, if the cumulative negative sequence current of more than 25% over one sampling period is greater than 2.5I... e , such as I e =50A, 2.5I e =125A, then it is determined to be a two-phase short circuit, and F is sent. f Signal.

[0091] Motor and connected equipment fault diagnosis: Monitor the instantaneous current change within a 20ms current cycle: If the current exhibits a pattern of first increasing, then decreasing, and then increasing again, such as rising from 80A to 120A and then decreasing to 80A, with the cycle repeating, it is determined that the motor rotor is out of sync or the reducer is stuck, and a fault prediction signal F is sent. b .

[0092] Winding diagnosis: Harmonic content can indicate inter-turn short circuits in motor windings; sudden current increase and three-phase imbalance rate exceeding 5% can indicate inter-phase short circuits in motors; increased leakage current can indicate decreased motor insulation.

[0093] Bearing diagnosis: The presence of characteristic sidebands in the current spectrum indicates early damage to the motor, and a significant increase in current fluctuation amplitude can predict motor bearing wear.

[0094] Rotor diagnosis: The current spectrum shows slip frequency characteristic components, indicating a broken rotor bar; the current waveform fluctuates periodically, indicating an eccentric fault.

[0095] The controller operates on a 24-hour cycle, incorporating the fault signal F from the protection system after a fault occurs. f Fault prediction signals with degradation warning The protection mechanism is implemented, and the specific logic is as follows:

[0096] Calculation of operating stability index: Based on the statistics of the previous work cycle, the actual operating current during 8 hours of operation and the remaining standby time is less than I. e The percentage of time the current is less than I during 7.2 hours out of an 8-hour period. e If the proportion is 90%, then the operating condition stability index = 90%.

[0097] Fault prediction rate F b1 Calculation: Statistical analysis of F within a work cycle b The ratio of the number of signal triggers to the total number of monitoring times—for example, if 1000 monitoring times are conducted in a day, 950 of them will trigger. ,but =95%.

[0098] Execution of protective actions:

[0099] If a single work cycle If the failure rate is ≥80%, the fault prediction for this cycle is deemed effective but does not trigger a shutdown; observation of the next cycle is required. If the next cycle is affected by changes in operating conditions, such as a decrease in the hardness of the coal seam being cut, the fault prediction will be deemed effective. If the threshold drops to 70%, no warning will be issued.

[0100] If two consecutive work cycles meet If the load is ≥95% and the operating stability index is ≥90%, intermittent protection will be triggered: In the first cycle, the machine will be shut down and locked for 10 minutes, prompting the user to check for load degradation, such as cutter tooth wear; if in the third cycle… If it remains stable at ≥95%, then proceed according to the formula. Calculate the protection time.

[0101] If triggered In the event of a short circuit fault, the controller immediately drives the contactor to disconnect the load power supply, thus providing post-fault protection. All outputs are sent to the actuator via relays to ensure reliable shutdown of the load.

[0102] This application features multiple harmonic content data acquisition, analysis, and storage capabilities. Based on the characteristics of the tunneling equipment's multi-branch network, shared bus power supply, and nonlinear loads, it performs harmonic analysis and data storage on the tunneling equipment's power supply network and nonlinear loads. The system performs high-speed sampling of various data categories, and the acquired harmonic current and voltage data is analyzed online and stored offline. By monitoring harmonic content, power quality is assessed, providing a basis for implementing filtering or compensation measures. Monitoring the harmonic content of nonlinear loads reveals the tunneling equipment's electrical control system's filtering and mitigation capabilities for nonlinear load circuits, and monitors the quality of the energy feedback power supply for the four-quadrant frequency converter, preventing impact on other linear loads. Harmonic content monitoring allows for automatic switching between different feedback modes for nonlinear loads. Built-in algorithms calculate various power parameters of the tunneling equipment: THD (Total Harmonic Distortion), UHD (Upper Harmonic Distortion), and ILD (Increased Harmonic Distortion). High-precision chips are used to capture voltage and current waveforms at a sampling rate of 20,000 times per second. The harmonic spectrum is decomposed using an FFT algorithm, and different harmonics are classified based on the load characteristics and operating conditions of the tunneling equipment. This allows for the identification of harmonic content variations under different operating conditions. The tunneling equipment's electrical control system can automatically compensate and filter according to different operating conditions, reducing energy loss, heat generation, and improving reliability and power quality. The stored high-speed sampled data is then analyzed offline using artificial intelligence. Deep learning models are employed, combined with different underground operating conditions, and using operating conditions and load characteristics as references, to capture data variations during tunneling equipment operation, discovering patterns in data variation and providing models and strategies for tunneling equipment fault prediction.

[0103] The method in this embodiment is based on the above-described electronic control system and specifically includes the following steps:

[0104] Step S1: High-speed synchronous sampling

[0105] Start the high-speed processor: After the tunneling equipment is powered on, the high-speed processor automatically initializes the A / D conversion device, sets the sampling frequency to 50 microseconds, and starts the time window marking function, generating a timestamp every 50 microseconds.

[0106] Signal input: The secondary current signal (0-5A) of the multi-circuit current transformer and the secondary voltage signal (0-100V) of the voltage transformer are input to the sampling terminal of the high-speed processor through analog signal lines. The A / B / C phases of the same circuit are switched in time-division by a high-speed electronic switching switch.

[0107] Synchronous sampling: The high-speed processor synchronously collects the current signal and bus voltage signal of all load circuits within each time window, binds the sampled value with a timestamp, and temporarily stores it in the internal cache with a cache capacity of ≥1MB to ensure that no data is lost.

[0108] Step S2: Raw signal processing

[0109] Signal Calculation: The high-speed processor uses the Short-Time Fourier Transform algorithm to calculate the original signal in the cache, obtaining the RMS current value, RMS voltage value, phase angle, and 2nd-50th harmonic data for each circuit; simultaneously, it determines the actual operating current I according to the logic in "2.1.2". S .

[0110] Data distribution: The effective values ​​of current and voltage are transmitted to the traditional controller via RS485 bus, and the original power signals with timestamps are packaged and sent to the embedded industrial computer via Ethernet.

[0111] Step S3: Data storage and retrieval

[0112] Categorized storage: After receiving files, the embedded industrial control computer stores them to the solid-state drive according to a three-level directory structure of load category-phase-time.

[0113] Data Extraction: Users can extract data in two ways:

[0114] Offline extraction: Insert the USB flash drive into the industrial computer's USB port, select the file via the touchscreen, and click export.

[0115] Wireless extraction: Select the corresponding file in the mobile APP, send an extraction request, and the industrial control computer will compress the file and send it to the APP via WiFi.

[0116] Step S4: Online Health Diagnosis

[0117] Load characteristic classification: The embedded industrial control computer reads the load identifier of the data file, such as the load is truncated, and automatically matches the corresponding diagnostic algorithm, that is, the heavy load algorithm.

[0118] Anomaly type analysis: Classified by electrical / mechanical anomalies and symmetrical / asymmetrical anomalies.

[0119] Electrical anomalies, such as short circuits: Analyze the instantaneous peak current and negative sequence current, and determine the three-phase / two-phase short circuit according to the logic of "2.2.2".

[0120] Mechanical abnormalities, such as jamming: Analyze the regular changes in the current cycle to determine the fault of the motor or reducer.

[0121] Diagnostic result output: The diagnostic results, such as the A-phase blockage of the cut-off load, will be displayed. =95% is displayed on the industrial control computer touch screen and mobile APP.

[0122] Step S5: Protection and Early Warning Execution

[0123] Signal reception: The controller receives signals sent by the high-speed processor. Signals and industrial control computer transmission Signal and operating condition stability index.

[0124] Protection Judgment: Determine whether protection is triggered according to the logic in 2.3. If it is triggered for two consecutive cycles... If the stability index is ≥95% and the stability index is ≥90%, then an intermittent shutdown will be triggered; if triggered If the machine fails to shut down, it will be shut down immediately.

[0125] Action execution: The controller drives the contactor to disconnect the load power supply and simultaneously illuminates the fault indicator light. f Corresponding to the red light, F b The corresponding yellow light indicates the cause of the fault, and the operation panel displays the cause of the fault, such as a three-phase short circuit or a warning of tooth wear.

[0126] Step S6: Selection of feedback control current

[0127] To address the slow speed regulation issue of traditional RMS feedback, this embodiment uses the average instantaneous current of a fraction of a k-wave as the feedback current:

[0128] Matching load type with k value: Setting the k value:

[0129] For stable loads, such as fans and hydraulic pumps: k=8, one cycle is divided into 8 segments, each segment is 2.5ms.

[0130] For heavy loads, such as truncated loads: k=2, one cycle is divided into 2 segments, each segment is 10ms.

[0131] Frequent load starts, such as loading: k=4, one cycle is divided into 4 segments, each segment is 5ms.

[0132] For heavy-load start-up loads, such as transportation: k=6, one cycle is divided into 6 segments, each segment ≈3.33ms.

[0133] Sampling point count calculation: Sampling period T = 50 microseconds, the number of sampling points for one 20ms cycle is i = 20 × 1000 / 50 = 400; calculate the number of sampling points i used for feedback based on the k value. j =i / k, for example, when cutting load k=2, i j =400 / 2=200.

[0134] Feedback current calculation: An improved Fourier algorithm is used to calculate the instantaneous average current of the 1 / k wave. This average value is sent to the frequency converter as the feedback current, enabling precise speed regulation of the load. The speed regulation response time is reduced from the traditional 100ms to less than 25ms. Although embodiments of the present invention have been shown and described, these specific embodiments are merely illustrative of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art can make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. An electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment, comprising a multi-loop three-phase current transformer, a common bus three-phase voltage transformer, a processor / analyzer, a transmitter, and a controller, wherein the controller is used to perform control of various actuators of the tunneling equipment, sensor information processing, status signal interaction, operation mode signal processing, and human-machine interaction data transmission, characterized in that, It also includes high-speed processors and embedded industrial control computers; The high-speed sampling module completes wide-range, multi-variable power synchronous sampling; the processing and analysis module completes the instantaneous value, effective value, power factor, and harmonic content of the actual electrical signal; the transmission module completes the real-time transmission of large-capacity data; the micro industrial computer stores the data; the controller receives the electrical signal analysis results and completes the functions of driving, executing, and displaying; at the same time, the high-speed processor calculates multiple harmonics and evaluates and analyzes the power quality and nonlinear load. The high-speed processor is connected to the multi-loop three-phase current transformer and the common bus three-phase voltage transformer, and is used to synchronously acquire the original secondary current signal and the original secondary voltage signal of the power supply bus of each loop with different load categories in real time at a sampling frequency of 50 microseconds. The high-speed processor has multiple A / D conversion devices embedded in it. Each A / D conversion device has an independent sampling loop. Each load loop occupies one A / D channel. The A, B, and C phases of the same loop are converted by A / D in a time-sharing manner through a high-speed electronic conversion switch. The three-phase power supply voltage shares one A / D channel. The high-speed processor aligns and integrates the data from different current and voltage sensors in time or space to realize synchronous and same-frequency sampling of multi-loop current and bus voltage. The high-speed processor is also used to calculate the acquired raw signal using the short-time Fourier algorithm and wavelet transform to obtain the effective values ​​of current, voltage, phase angle, and harmonics of each loop; and to calculate the upper half-wave value within the full cycle based on the load rated current I. Compared with the calculated value of the second half wave The average value determines the actual operating current. The effective values ​​of the current and voltage are transmitted to the controller for traditional electrical protection. The high-speed processor is communicatively connected to the embedded industrial control computer and is used to transmit the packaged original electrical signals to the embedded industrial control computer. The embedded industrial control computer is used to store the original electrical signals and classify and store data according to the load categories of hydraulic system oil pump load, coal cutting system cutting load, rake claw system loading load, conveying system transport load, and dust removal load, combined with the phases A, B, and C and the time sequence. The embedded industrial control computer is also used to interact with the high-speed processor via FTP protocol and to realize offline data retrieval via USB interface or external wireless communication interface. The embedded industrial control computer is also used for online diagnosis: classifying and analyzing current data according to the load characteristics of stable hydraulic oil pump load, heavy-duty cutting load, and frequently starting load; using different algorithms according to the type of signal anomaly caused by electrical / mechanical and the symmetrical / asymmetrical anomaly, to determine three-phase short circuit, two-phase short circuit, and asynchronous or jammed faults in motor connection equipment. The controller is used to execute protection strategies: combining faults With fault prediction Fault prediction rate is measured using a 1-day work cycle. ; When two consecutive work cycles When the operating condition stability index is greater than 90% and the actual operating current is ≥95%, an intermittent protection signal is issued, initially with a 10-minute shutdown and lockout per day. The operating condition stability index is the percentage of the actual operating current that is less than the rated current in the previous working cycle. When the stability exceeds 95%, the protection lockout shutdown time is calculated according to the formula. Calculation; protection signal It is used to drive the load to stop.

2. The electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 1, characterized in that: The A / D conversion logic of the high-speed processor is as follows: Phase A, Phase B, and Phase C of the same load circuit are sequentially connected to the corresponding A / D channel of the circuit through a high-speed electronic conversion switch. The three-phase power supply voltage is fixedly connected to a dedicated A / D channel. Data from different current and voltage sensors are aligned and integrated in time or space to ensure the accuracy of power factor calculation for each circuit. By monitoring power factor, current amplitude, and operating conditions in real time, the load can be protected in real time by working period and working area. Different working periods and working areas can be distinguished by power factor and load characteristics, so as to implement more reliable protection. The method has changed from time delay and current amplitude protection to a combination of power factor and current. By monitoring the power factor, the basis for the performance of the design power and the actual load is provided, and data samples are provided for subsequent design and selection.

3. The electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 1, characterized in that: The high-speed processor determines the actual operating current. The specific logic is as follows: If the calculated value of the first half of the first full cycle Compared with the calculated value of the second half wave If the difference is less than 0.5I, then ; like and The difference is greater than 0.5 Then the calculated value of the first half of the second full cycle will be... and In comparison, if and If the difference is ≤0.5I, then And so on; Through the above logic, the high-speed processor controls the electrical short-circuit protection fault time to within 10ms.

4. The electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 1, characterized in that: The classification and storage logic of the embedded industrial control computer is as follows: Create first-level folders based on load categories, corresponding to hydraulic oil pump loads, cutting loads, loading loads, transportation loads, and dust removal loads respectively; Each first-level folder contains second-level subfolders categorized as Phase A, Phase B, and Phase C. Each second-level subfolder is divided into several storage files in chronological order, and the file splitting period matches the sampling data capacity requirements; The wireless communication interface supports setting the data extraction category, time range, and file size to achieve accurate extraction of fault data.

5. The electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 1, characterized in that: The fault diagnosis logic of the embedded industrial control computer is as follows: Three-phase short circuit detection: If the instantaneous currents of phases A, B, and C, after the phase crossing zero point, accumulate to more than 25% of the rated load current over one sampling period, then the short circuit criterion is met. When the value is 8 times the value, it is determined to be a three-phase short circuit; Two-phase short circuit determination: The negative sequence current formed by the instantaneous currents of any two phases (A, B, and C) after the phase zero-crossing point accumulates to more than 25% of the total current over one sampling period. When the value is 2.5 times the value, it is determined to be a two-phase short circuit; Motor and connected equipment fault diagnosis: If the instantaneous current shows a regular increase within one current cycle during the rotation of the motor and connected equipment, it is determined to be a fault of equipment asynchrony or jamming.

6. The electrical control system for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 1, characterized in that: The controller's protection strategy also includes: if within a single working cycle If the failure rate is ≥80%, the fault prediction for that cycle is considered valid; if the failure rate is ≥80% in the next work cycle, the fault prediction is considered valid. The controller does not issue a warning shutdown signal when the temperature drops; it only does so when two consecutive operating cycles meet the requirements. Intermittent protection signals are triggered only when the operating condition stability index is greater than 90% and the operating condition stability index is greater than 95%.

7. A method for high-speed sampling health diagnosis and protection of tunneling equipment, characterized in that, Includes the following steps: S1: High-speed synchronous sampling The high-speed processor synchronously acquires the original current signals of the secondary side of multi-loop three-phase current transformers and the original voltage signals of the secondary side of three-phase voltage transformers with a common bus at a sampling frequency of 50 microseconds. The high-speed processor allocates sampling channels by using multiple embedded independent A / D conversion devices, with one A / D channel for one loop and one A / D channel for three-phase voltage. The A / B / C phases of the same loop are sampled in a time-division manner through high-speed electronic conversion switches, and the original sampled values ​​marked with time windows are established to ensure sampling synchronization. S2: Raw Signal Processing The high-speed processor uses the short-time Fourier algorithm and wavelet transform to calculate the acquired raw signal and obtain the effective value of the current, effective value of the voltage, phase angle and each harmonic of each circuit. Using the rated current I as a reference, the calculated values ​​of the upper half-wave within the full cycle are obtained. Compared with the calculated value of the second half wave The difference is used to determine the actual operating current I. S The effective values ​​of the current and voltage are transmitted to the controller, and the packaged original power signal is transmitted to the embedded industrial computer. S3: Data Storage and Retrieval The embedded industrial computer stores the original power signals according to load type, phase, and time sequence; it receives high-speed processor data via FTP protocol and realizes offline data extraction via USB interface or wireless communication interface. S4: Online Health Diagnosis The embedded industrial control computer analyzes current data according to load characteristics, and uses different algorithms according to electrical / mechanical abnormality type and symmetrical / asymmetrical abnormality to determine three-phase short circuit, two-phase short circuit and motor connection equipment fault; S5: Protection and Early Warning Execution The controller combines fault With fault prediction Testing is conducted on a 1-day work cycle. ; When two consecutive work cycles When the efficiency is ≥95% and the operating condition stability index is greater than 90%, an intermittent protection signal is issued; When the stability exceeds 95%, according to Calculate the protection time; use the protection signal Drive load shutdown.

8. The method for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 7, characterized in that: In step S1, the sampling synchronization control logic of the high-speed processor is as follows: based on the time window, ensure that the sampling of all loop current signals and bus voltage signals is completed within the same time window, and the time-division sampling interval of phases A / B / C of the same loop does not affect the power factor calculation accuracy.

9. The method for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 7, characterized in that: In step S4, the specific basis for fault judgment is as follows: Three-phase short circuit: After the instantaneous current of phases A / B / C crosses zero, the cumulative current exceeding 25% of one sampling period exceeds 8I. e ; Two-phase short circuit: When the negative sequence currents of any two phases accumulate to more than 25% of the total current over one sampling period after the phase crosses zero, exceeding 2.5I. e ; Motor fault: The instantaneous current increases regularly within one current cycle.

10. A method for high-speed sampling health diagnosis and protection of tunneling equipment according to claim 7, characterized in that: It also includes the feedback control current selection step: Set a cycle division coefficient k according to the load type, and take k=2, 4, 6, 8; The number of sampling points i = 20 × 1000 / T for one cycle is calculated based on the sampling period T. The number of sampling points i used for feedback calculation is then determined. j =i / k; An improved Fourier algorithm is used to calculate the instantaneous average current of the k-th wave, and this average value is used as the feedback current for load speed control.

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