Digital monitoring operation and maintenance system, method, equipment and medium for excitation carbon brush and collecting ring

Abstract

The invention discloses an excitation carbon brush and collecting ring digital monitoring operation and maintenance system, method and device and a medium, and belongs to the technical field of power equipment monitoring, and the method comprises the steps: obtaining the real-time current data of a plurality of carbon brushes, and determining the deviation degree of each carbon brush current relative to a reference current; according to the generator operation condition parameters, determining a deviation threshold value used for judging carbon brush current abnormity; when it is detected that the current deviation degree of the target carbon brush exceeds a deviation threshold value, an adjustment control signal is generated; and responding to the adjustment control signal, performing mechanical stimulation operation on the target carbon brush, and changing the contact state of the target carbon brush and the collector ring. Automatic balance adjustment of the current of the carbon brush is realized through mechanical stimulation operation, and the service life of the carbon brush is prolonged.

Description

Technical Field

[0001] This invention relates to the field of power equipment monitoring technology, specifically to a digital monitoring and maintenance system, method, equipment, and medium for excitation carbon brushes and slip rings. Background Technology

[0002] As a key component of synchronous generators, the generator excitation system's operational stability directly impacts the safe and reliable operation of the power system. The sliding electrical contact system, composed of excitation carbon brushes and slip rings, plays a crucial role in transmitting excitation current to the rotor windings. In large generator sets, multiple carbon brushes are typically connected in parallel to meet the demands of high current transmission. As a consumable component, monitoring the operational status of carbon brushes has always been a key focus of power plant equipment management. In recent years, digital monitoring technology has been widely applied in the field of power equipment condition monitoring. Real-time acquisition of parameters such as carbon brush current, temperature, and vibration to achieve online monitoring of carbon brush operating status has become an industry trend.

[0003] However, existing carbon brush monitoring systems primarily focus on parameter acquisition and over-limit alarms, lacking effective automatic adjustment mechanisms. In actual operation, uneven current distribution frequently occurs among multiple carbon brushes operating in parallel due to factors such as uneven carbon brush pressure, differences in contact resistance, and varying degrees of wear. Excessive current on some carbon brushes can lead to localized overheating, accelerating brush wear and, in severe cases, even causing sparking or arcing. Traditional solutions rely on manual inspection and adjustment, which are not only slow to respond but also difficult to guarantee effective adjustments. Furthermore, existing monitoring systems use fixed thresholds, which cannot adapt to the generator's operating characteristics under different load conditions, easily leading to false alarms or missed alarms. If the problem of uneven carbon brush current is not effectively resolved in the long term, it will significantly shorten the lifespan of the carbon brushes, increase maintenance costs, and affect the economic efficiency of the unit's operation. Summary of the Invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by this invention is: how to achieve automatic balance adjustment of carbon brush current, accurate judgment of abnormal state, and active improvement of contact state through a deviation threshold determination mechanism based on operating conditions and a mechanical stimulation adjustment method, while ensuring operational safety under high temperature and ignition conditions.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a digital monitoring and maintenance system for excitation carbon brushes and slip rings, comprising: acquiring real-time current data of multiple carbon brushes and determining the degree of deviation of the current of each carbon brush relative to a reference current; Based on the generator operating parameters, determine the deviation threshold for judging abnormal carbon brush current; When the current deviation of the target carbon brush is detected to exceed the deviation threshold, an adjustment control signal is generated; In response to the adjustment control signal, a mechanical stimulation operation is performed on the target carbon brush to change the contact state between the target carbon brush and the slip ring.

[0007] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, wherein determining the degree of deviation of each carbon brush current from the reference current includes: Collect current data from multiple carbon brushes on the same slip ring; A reference current is calculated based on the current data of the multiple carbon brushes, and the reference current is a statistical value of the current data of the multiple carbon brushes. Calculate the difference between the current value of each carbon brush and the reference current; The degree of deviation is determined based on the difference between the current value of each carbon brush and the reference current, and the rated parameters of the carbon brush.

[0008] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, the step of determining the deviation threshold for judging abnormal carbon brush current based on generator operating parameters includes: Obtain the excitation current and rotor speed of the generator; Consult the carbon brush current deviation comparison table based on the excitation current value and the rotor speed; Read the corresponding deviation threshold from the carbon brush current deviation lookup table; The carbon brush current deviation comparison table is established based on the wear pattern of carbon brushes under different excitation currents and speeds.

[0009] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, the system reads the corresponding deviation threshold from the carbon brush current deviation lookup table, including: Obtain the cumulative running time of the target carbon brush; Based on the excitation current value, the rotor speed, and the cumulative operating time, the deviation threshold is looked up from the carbon brush current deviation lookup table; The carbon brush current deviation reference table includes deviation thresholds set for carbon brushes with different usage durations. The deviation threshold for carbon brushes whose cumulative operating time exceeds a set proportion of their rated lifespan is greater than the deviation threshold for carbon brushes whose cumulative operating time does not exceed the set proportion.

[0010] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, the mechanical stimulation operation performed on the target carbon brush includes: Control the brush holder drive device associated with the target carbon brush; The brush holder is displaced by the brush holder drive device. The displacement change includes a first action that moves the carbon brush a first displacement distance away from the collector ring and a second action that moves the carbon brush a second displacement distance closer to the collector ring, wherein the first displacement distance and the second displacement distance are equal. The displacement change is repeated within a set time period.

[0011] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, the mechanical stimulation operation on the target carbon brush further includes: After performing the displacement change consisting of the first action and the second action, the real-time current value of the target carbon brush is obtained; The real-time current value is compared with the current value before the displacement change to determine the magnitude of the current change; If the current change amplitude is less than the change threshold, then in the next displacement change, both the first displacement distance and the second displacement distance will be adjusted to a set multiple of the current displacement distance; If the current change amplitude is greater than or equal to the change threshold and the current deviation of the target carbon brush drops below the deviation threshold, then the current first displacement distance and second displacement distance are maintained and the process continues until the set number of times is completed; If, after performing a set number of displacement changes, the current deviation of the target carbon brush still exceeds the deviation threshold, the target carbon brush is marked as an abnormal carbon brush and the physical location identifier of the target carbon brush is output.

[0012] As a preferred embodiment of the digital monitoring and maintenance system for excitation carbon brushes and slip rings described in this invention, the generation of the adjustment and control signal includes graded judgment conditions: Acquire the temperature data of the target carbon brush and the arc intensity data of the corresponding slip ring region; If the temperature data is lower than the first temperature threshold, the adjustment control signal is generated directly. If the temperature data is between the first temperature threshold and the second temperature threshold, the adjustment control signal is generated when the arc intensity data is lower than the arc threshold, and the generation of the adjustment control signal is prohibited when the arc intensity data is higher than the arc threshold. If the temperature data is higher than the second temperature threshold, the generation of the adjustment control signal is prohibited and a high temperature alarm message is output.

[0013] This invention provides a digital monitoring and maintenance method for excitation carbon brushes and slip rings.

[0014] To address the aforementioned technical problems, the present invention further provides the following technical solution: a digital monitoring and maintenance method for excitation carbon brushes and slip rings, comprising a current monitoring module, a threshold determination module, a control signal generation module, and an execution module, wherein: The current monitoring module is used to acquire real-time current data of multiple carbon brushes and determine the degree of deviation of the current of each carbon brush relative to the reference current. The threshold determination module is used to determine the deviation threshold for judging abnormal carbon brush current based on the generator operating condition parameters; The control signal generation module is used to generate an adjustment control signal when the detected current deviation of the target carbon brush exceeds the deviation threshold. The execution module is used to respond to the adjustment control signal, perform mechanical stimulation operation on the target carbon brush, and change the contact state between the target carbon brush and the slip ring.

[0015] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, characterized in that the processor executes the computer program to implement the steps of the digital monitoring and maintenance system for excitation carbon brushes and slip rings.

[0016] The present invention provides a computer-readable storage medium having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of the aforementioned digital monitoring and maintenance system for excitation carbon brushes and slip rings.

[0017] The beneficial effects of this invention are as follows: When the generator's operating conditions change, this invention determines the deviation threshold of the carbon brush current based on the current operating conditions, thereby ensuring the accuracy of anomaly detection under variable loads. Furthermore, upon detecting an abnormality in the carbon brush current, mechanical stimulation is immediately introduced to actively intervene in the contact state between the carbon brush and the slip ring, overcoming the limitations of traditional monitoring which can only provide passive warnings, and achieving a leap from state detection to active control. This invention utilizes the correlation established between the degree of carbon brush current deviation and mechanical stimulation parameters, continuously revising the stimulation intensity based on real-time feedback of the deviation, forming a closed-loop control. Therefore, the physical contact characteristic-based control of this invention provides a faster response and more accurate measurement compared to manual intervention. Simultaneously, when the temperature exceeds the limit or an arc flash occurs, this invention stops the mechanical intervention action based on the judgment result, avoiding the risk of applying mechanical action under hazardous conditions, and achieving safety protection through the fusion of multiple parameters. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is an overall flowchart of a digital monitoring and maintenance system for excitation carbon brushes and slip rings provided in one embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of a digital monitoring and maintenance system for excitation carbon brushes and slip rings provided in one embodiment of the present invention; Figure 3 This is a computer equipment diagram of a digital monitoring and maintenance system for excitation carbon brushes and slip rings provided in one embodiment of the present invention. Detailed Implementation

[0020] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0021] Example 1, referring to Figure 1 This is the first embodiment of the present invention, which provides a digital monitoring and maintenance method for excitation carbon brushes and slip rings, including: S100: Acquire real-time current data of multiple carbon brushes and determine the degree of deviation of each carbon brush current from the reference current; S200: Determine the deviation threshold for judging abnormal carbon brush current based on the generator operating condition parameters; S300: When the current deviation of the target carbon brush is detected to exceed the deviation threshold, an adjustment control signal is generated; S400: Responds to the regulation control signal and performs mechanical stimulation on the target carbon brush to change the contact state between the target carbon brush and the slip ring.

[0022] It should be noted that the generator excitation system uses multiple carbon brushes connected in parallel to supply power to the rotor windings. Ideally, each carbon brush should evenly share the excitation current. However, in actual operation, factors such as aging of the carbon brush clamping springs, brush holder installation errors, and uneven carbon brush material lead to differences in the contact resistance between the carbon brushes and the slip rings. Carbon brushes with lower contact resistance carry a larger current, resulting in increased local temperature rise and a faster carbon powder wear rate; carbon brushes with higher contact resistance carry a smaller current and fail to fully utilize their conductivity. Over long-term operation, this uneven current distribution creates a vicious cycle: high-current carbon brushes experience accelerated wear, further deteriorating the contact condition; low-current carbon brushes, lacking sufficient current density, are prone to oxide film formation, increasing contact resistance.

[0023] Therefore, to address the aforementioned problem of uneven carbon brush current distribution, steps S100 to S400 are used to quantitatively assess the deviation of each carbon brush current, and a deviation threshold query mechanism associated with generator operating conditions is constructed to solve the adaptability problem of a fixed threshold under varying operating conditions. This invention actively intervenes in the contact state between the carbon brush and the slip ring through mechanical stimulation. By briefly changing the contact pressure, the oxide film is damaged, and the carbon powder is redistributed, promoting a more uniform contact resistance and achieving automatic balance adjustment of the carbon brush current.

[0024] Example 2, refer to Figure 1 This is the second embodiment of the present invention, which provides a digital monitoring and maintenance method for excitation carbon brushes and slip rings.

[0025] S100: Acquire real-time current data of multiple carbon brushes and determine the degree of deviation of each carbon brush current from the reference current.

[0026] It is important to note that in a generator excitation system, the number of carbon brushes installed on each slip ring is determined by the magnitude of the excitation current. Large steam turbine generators typically have 8 to 16 carbon brushes on a single slip ring. These carbon brushes are connected in parallel to share the task of transmitting the excitation current. Ideally, the total excitation current should be evenly distributed among the carbon brushes. However, factors such as differences in contact resistance, uneven clamping force, and varying degrees of wear cause the actual current distribution to deviate from this ideal state.

[0027] Step S100 determines the degree of deviation of each carbon brush current from the reference current, including steps A1 to A4: Step A1: Collect current data from multiple carbon brushes on the same collector ring.

[0028] Current data is acquired via a current sensor mounted on the carbon brush leads. Two types of sensors are used: Hall effect current sensors and shunt current sensors. The former achieves non-contact measurement based on the Hall effect, while the latter calculates the current value by measuring the voltage across the shunt resistor. The sampling frequency is set between 10Hz and 100Hz to ensure the capture of transient changes in the excitation current. Considering electromagnetic interference in the excitation circuit, the raw sampling data undergoes low-pass filtering, with the cutoff frequency set to 0.4 times the sampling frequency to eliminate high-frequency noise components.

[0029] Step A2: Calculate the reference current based on the current data of multiple carbon brushes. The reference current is the statistical value of the current data of multiple carbon brushes. The statistical values ​​can be calculated using the following methods: arithmetic mean method (summing the current values ​​of n carbon brushes and dividing by n); median method (sorting the n current values ​​by size and taking the value at the (n+1) / 2 position (n is odd) or the average of the values ​​at the n / 2 and n / 2+1 positions (n ​​is even); and truncated mean method (removing the largest and smallest 10% of data and calculating the average of the remaining data). The selection criteria are: arithmetic mean is used when the carbon brush current distribution is close to a normal distribution; median is used when there are individual outliers; and truncated mean is used when both stability and representativeness need to be considered.

[0030] Step A3: Calculate the difference between the current value of each carbon brush and the reference current.

[0031] difference The calculation uses the relative deviation form: ; in, Let i be the actual current of the i-th carbon brush. This is the reference current. It should be noted that the relative deviation eliminates the influence of different load levels on the deviation assessment, making the degree of deviation comparable across the entire operating range.

[0032] Step A4: Determine the degree of deviation based on the difference between the current value of each carbon brush and the reference current, and the rated parameters of the carbon brush. Degree of Deviation Defined as: ; in, This refers to the rated current of the carbon brush. The rated current of the carbon brush is determined according to the technical parameters provided by the manufacturer, and is usually the product of the rated current density of the carbon brush (2-10 A / cm²) and the cross-sectional area of ​​the carbon brush. (Normalization process is required to determine the degree of deviation.) It is a dimensionless parameter, which facilitates lateral comparison and threshold setting between carbon brushes of different specifications.

[0033] Through the above processing steps, this invention establishes a quantitative evaluation method for carbon brush current deviation based on statistical reference values. Compared with traditional methods that only monitor the total excitation current or a single temperature parameter, this invention, through real-time calculation of individual current deviations, can detect anomalies in the early stages of current distribution imbalance, providing a time window for preventive maintenance and avoiding accelerated wear and overheating failures caused by long-term overload of local carbon brushes.

[0034] S200: Determine the deviation threshold for judging abnormal carbon brush current based on the generator operating parameters.

[0035] The operating conditions of carbon brushes vary under different generator operating conditions. During low-load operation, the excitation current is small, the current density between the carbon brush and the slip ring is low, and the contact state is relatively unstable. During high-load operation, the excitation current increases, the current density rises, and the contact between the carbon brush and the slip ring tends to stabilize. Therefore, using a fixed deviation threshold to determine carbon brush current anomalies can lead to misjudgments or missed detections. This invention establishes a deviation threshold determination mechanism associated with operating conditions to achieve accurate judgment of carbon brush current anomalies.

[0036] Step S200 includes steps S210 to S230: Step S210: Obtain the excitation current value and rotor speed of the generator.

[0037] The excitation current value is obtained by measuring a current transformer installed in the excitation circuit, with a measurement accuracy class of not less than 0.5. The secondary side signal of the current transformer is converted into a standard voltage signal by a signal conditioning circuit, and then sampled by an analog-to-digital converter before being sent to the monitoring system. The rotor speed is measured by an optical encoder or a magnetoelectric speed sensor installed on the generator shaft end, with a measurement resolution of not less than 360 pulses per revolution. The sampling period of both parameters is synchronized with the carbon brush current sampling to ensure data time consistency.

[0038] Step S220: Refer to the carbon brush current deviation comparison table based on the excitation current value and rotor speed.

[0039] The carbon brush current deviation lookup table uses a two-dimensional lookup table structure. The horizontal axis represents the excitation current range, and the vertical axis represents the rotor speed range. The excitation current is divided into multiple ranges according to the percentage of the rated excitation current, such as: 0-20%, 20%-40%, 40%-60%, 60%-80%, 80%-100%, 100%-120%. The rotor speed is divided according to the percentage of the rated speed, such as: 0-50%, 50%-80%, 80%-95%, 95%-105%. Each operating point corresponds to a deviation threshold, forming a lookup matrix.

[0040] Step S230: Read the corresponding deviation threshold from the carbon brush current deviation lookup table.

[0041] The lookup process employs a bilinear interpolation algorithm. When the actual operating parameters fall between the nodes in the table, interpolation is performed using the threshold values ​​of four adjacent nodes. For example, when the excitation current is 55% of the rated value and the rotor speed is 92% of the rated value, the system automatically locates the range (40%-60%, 80%-95%) and performs interpolation based on the position of the specific values ​​within the range to obtain an accurate deviation threshold.

[0042] The carbon brush current deviation comparison table is established based on the wear pattern of carbon brushes under different excitation currents and speeds.

[0043] The process of establishing the comparison table includes: accumulating long-term operating data and statistically analyzing parameters such as the wear rate, current distribution characteristics, and failure probability of carbon brushes under different operating conditions; establishing a wear model by combining the physical properties of carbon brush materials, such as the temperature coefficient of resistivity and the variation law of friction coefficient; and forming the final comparison table data through experimental verification and field data correction.

[0044] Step S230 involves reading the corresponding deviation threshold from the carbon brush current deviation lookup table, including steps S231 and S232: Step S231: Obtain the cumulative running time of the target carbon brush.

[0045] The cumulative operating time is monitored using the timer function of the monitoring system, starting from the installation and commissioning of the carbon brush, with an accuracy down to the hour. The timing data is stored in non-volatile memory to ensure data integrity after power failure. When a carbon brush is replaced, maintenance personnel reset the corresponding carbon brush's timer via a human-machine interface. The system also records the installation date, model, and specifications of each carbon brush for easy lifecycle management.

[0046] Step S232: Based on the excitation current value, rotor speed and cumulative running time, look up the deviation threshold from the carbon brush current deviation reference table.

[0047] The expanded lookup table adds a time dimension, forming a three-dimensional query structure. Cumulative running time is divided as a percentage of the carbon brush's rated lifespan, for example: 0-25%, 25%-50%, 50%-75%, 75%-100%, and over 100%. The query algorithm has been upgraded to trilinear interpolation to ensure a reasonable deviation threshold is obtained under any operating condition and usage duration.

[0048] The carbon brush current deviation comparison table includes deviation thresholds set for carbon brushes with different usage durations. The deviation threshold for carbon brushes whose cumulative operating time exceeds a set percentage of their rated lifespan is greater than the deviation threshold for carbon brushes whose cumulative operating time does not exceed the set percentage.

[0049] Specifically, the deviation threshold for new carbon brushes (0-25% of rated lifespan) is relatively strict because new carbon brushes have a smooth surface and good contact, and the current distribution should be relatively uniform under normal circumstances; the threshold for mid-term carbon brushes (25%-75% of rated lifespan) is appropriately relaxed to allow for differences in current distribution due to normal wear; the threshold for aged carbon brushes (75%-100% of rated lifespan) is further relaxed, but serious imbalance still needs to be prevented; the threshold for carbon brushes that have exceeded their service life (more than 100% of rated lifespan) is the most lenient, with a focus on preventing extreme failures such as breakage and severe wear.

[0050] Through step S200, the present invention achieves accurate judgment of carbon brush current abnormalities, which not only avoids frequent false alarms caused by fixed thresholds, but also ensures the timely detection of real abnormalities, providing a reliable basis for subsequent adjustment and control.

[0051] S300: When the current deviation of the target carbon brush is detected to exceed the deviation threshold, an adjustment control signal is generated.

[0052] A carbon brush current deviation exceeding a threshold indicates that the current distribution imbalance has reached a level requiring intervention. However, directly performing mechanical adjustment carries risks, as mechanical action under high temperature or arcing conditions may exacerbate the malfunction. This invention ensures the safety of adjustment operations by introducing a graded judgment mechanism based on temperature and arc intensity.

[0053] Step S300 generates the regulation control signal, which includes graded judgment conditions, specifically: The system acquires temperature data of the target carbon brush and arc intensity data of the corresponding slip ring area. Temperature data is measured using a resistance temperature detector (RTD) or thermocouple sensor mounted on the brush holder, with the sensor probe in close contact with the brush tip. The temperature range is 0-200℃, and the response time is no more than 5 seconds. Arc intensity data is acquired using a photoelectric sensor installed inside the slip ring cover. The sensor uses a silicon photovoltaic cell as the photosensitive element, with a spectral response range covering 300-1100nm, capable of detecting arc light generated by poor contact between the carbon brush and the slip ring. The signals from both types of sensors are isolated, amplified, and filtered before being sent to the monitoring system.

[0054] If the temperature data is below a first temperature threshold, an adjustment control signal is directly generated. For example, the first temperature threshold is determined based on the carbon brush material characteristics; for electrographite carbon brushes, the first temperature threshold is set to 80℃, and for metal-graphite carbon brushes, it is set to 90℃. A temperature below the first threshold indicates that the carbon brush is within its normal operating temperature range. In this case, the current deviation is mainly caused by poor contact, and mechanical stimulation is safe and feasible. The adjustment control signal includes information such as the target carbon brush number, the current deviation level, and the suggested adjustment intensity.

[0055] If the temperature data falls between the first and second temperature thresholds, an adjustment control signal is generated when the arc intensity data is below the arc intensity threshold, and is disabled when the arc intensity data is above the arc intensity threshold. For example, the second temperature threshold is set to the first threshold plus 30°C, i.e., 110°C for electrographite carbon brushes and 120°C for metal graphite carbon brushes. The arc intensity threshold is automatically adjusted based on the background light intensity, typically set to 3-5 times the background light intensity. A temperature in the middle range indicates that the carbon brush has already generated some heat, and the adjustment strategy needs to be determined based on whether arcing occurs. Adjustment can be made cautiously when there is no arcing, but should be prohibited when arcing occurs to prevent exacerbating the malfunction.

[0056] If the temperature exceeds the second temperature threshold, the generation of regulation control signals will be prohibited, and a high-temperature alarm message will be output. Under high temperatures, the mechanical strength of the carbon brush material decreases, and forced mechanical action may cause the carbon brush to crack or accelerate wear. The high-temperature alarm message includes the carbon brush number, measured temperature, and duration, and will notify maintenance personnel via audible and visual alarms and remote communication. Immediate manual inspection and handling are recommended.

[0057] S400: Responds to the regulation control signal and performs mechanical stimulation on the target carbon brush to change the contact state between the target carbon brush and the slip ring.

[0058] By applying controlled reciprocating motion to the brush holder, a slight disturbance is generated at the contact interface between the carbon brush and the slip ring, which breaks up any oxide film that may form and redistributes the contact points, thereby improving the uniformity of the contact resistance.

[0059] Step S400 involves performing mechanical stimulation on the target carbon brush, including steps B1 to B4: Step B1: Control the brush holder drive mechanism associated with the target carbon brush. The brush holder drive mechanism employs either a piezoelectric ceramic actuator or an electromagnetic actuator. The piezoelectric ceramic actuator utilizes the inverse piezoelectric effect to generate micrometer-level precision displacement under the influence of an electric field, with a response frequency reaching the kilohertz level; the electromagnetic actuator drives the armature movement through electromagnetic force, offering a larger displacement range but slightly lower precision. The drive mechanism is connected to the brush holder via a flexible hinge or elastic connector, transmitting the driving force while allowing the brush holder to float normally.

[0060] Step B2: The brush holder is displaced by a brush holder drive mechanism. The drive signal is generated by a dedicated controller, and the signal waveform can be selected as a sine wave, triangular wave, or trapezoidal wave. The initial drive voltage is determined based on the carbon brush pressure and friction coefficient to ensure sufficient displacement without exceeding the material's elastic limit. The controller has overcurrent and overvoltage protection functions to prevent damage to the drive mechanism.

[0061] Step B3: Displacement change includes a first action that moves the carbon brush a first displacement distance away from the slip ring, and a second action that moves the carbon brush a second displacement distance closer to the slip ring. The first and second displacement distances are equal. The initial value of the displacement distance is set to 0.1-0.5 mm, with the specific value determined based on the carbon brush size and wear condition. The first action reduces the contact pressure between the carbon brush and the slip ring, helping to break up static friction and oxide film; the second action restores the contact pressure and re-establishes electrical contact. The execution speed of both actions is controlled within the range of 1-10 mm / s to avoid mechanical shock caused by excessive speed or affecting the adjustment effect by excessive slowness.

[0062] Step B4: Repeat the displacement change within the set time period. The cycle of a single reciprocating motion is 0.2-2 seconds, and it is performed continuously within a time period of 10-60 seconds. The number of repetitions is determined based on the initial deviation; the greater the deviation, the more stimulations are required. Continuously monitor the carbon brush current during execution, and terminate the process early once the desired effect is achieved.

[0063] It should be noted that performing mechanical stimulation on the target carbon brush also includes steps C1 to C3: Step C1: After the displacement change consisting of the first and second actions, acquire the real-time current value of the target carbon brush. Current acquisition is synchronized with displacement control to ensure that the acquired value is the steady-state current value after the actions are performed. The acquisition delay is set to 50-200ms after the action is completed, waiting for the transient current process to end. Multiple samples are taken and the average value is calculated to improve measurement reliability.

[0064] Step C2: Compare the real-time current value with the current value before the displacement change to determine the magnitude of the current change. The magnitude of the current change reflects the effectiveness of the mechanical stimulation. Simultaneously, record the direction of the current change (increase or decrease) to provide a basis for subsequent adjustments.

[0065] Step C3: Based on the current change amplitude determined in step C2, further judgment is made, specifically including: If the current change is less than the change threshold, the first and second displacement distances in the next displacement change will both be adjusted to a set multiple of the current displacement distance. The change threshold is set to 5%, indicating that the current stimulus intensity is insufficient. The set multiple is 1.2-1.5, gradually increasing the stimulus intensity. The upper limit of the displacement distance is set to 2mm to prevent over-adjustment from damaging the equipment.

[0066] If the current change is greater than or equal to the change threshold and the current deviation of the target carbon brush drops below the deviation threshold, the current first and second displacement distances are maintained and execution continues until the set number of times is completed. The set number of times is generally 10-20 times to ensure the stability of the adjustment effect. After execution, the system records the adjustment parameters and effects as the data basis for subsequent optimization.

[0067] If, after performing a set number of displacement changes, the current deviation of the target carbon brush still exceeds the deviation threshold, the target carbon brush is marked as abnormal and its physical location is output. The physical location identifier includes the unit number, slip ring number (positive / negative), and carbon brush serial number, facilitating quick location by maintenance personnel. The abnormality marker triggers a level two alarm, indicating the need for manual intervention and suggesting potential mechanical faults such as carbon brush jamming, severe wear, or spring failure.

[0068] Through the aforementioned mechanical stimulation operation and its feedback adjustment mechanism, this invention achieves active balance adjustment of the carbon brush current. Compared with traditional passive monitoring, this invention can immediately take corrective measures after detecting abnormal current distribution, preventing the problem from worsening. Compared with manual adjustment, mechanical stimulation operation has the advantages of rapid response, precise adjustment, and good repeatability, significantly improving the operational reliability of the excitation system.

[0069] In summary, this invention determines the deviation threshold of the carbon brush current based on the current operating conditions when the generator's operating conditions change, thereby ensuring the accuracy of anomaly detection under variable loads. Furthermore, upon detecting an abnormality in the carbon brush current, it immediately introduces mechanical stimulation to actively intervene in the contact state between the carbon brush and the slip ring, overcoming the limitations of traditional monitoring which only provides passive warnings, and achieving a leap from state detection to active control. This invention utilizes the correlation between the degree of carbon brush current deviation and mechanical stimulation parameters, continuously revising the stimulation intensity based on real-time feedback of the deviation, forming a closed-loop control. Therefore, this invention's control based on physical contact characteristics offers a faster response and more accurate measurement compared to manual intervention. Simultaneously, when the temperature exceeds the limit or arcing occurs, this invention stops the mechanical intervention based on the judgment result, avoiding the risk of applying mechanical action under hazardous conditions, and achieving safety protection through the fusion of multiple parameters.

[0070] Example 3, referring to Figure 2 This is the third embodiment of the present invention, which provides a digital monitoring and maintenance system for excitation carbon brushes and slip rings, including: The module comprises a current monitoring module, a threshold determination module, a control signal generation module, and an execution module, wherein: The current monitoring module is used to acquire real-time current data of multiple carbon brushes and determine the degree of deviation of the current of each carbon brush relative to the reference current. The threshold determination module is used to determine the deviation threshold for judging abnormal carbon brush current based on the generator operating condition parameters; The control signal generation module is used to generate an adjustment control signal when the detected current deviation of the target carbon brush exceeds the deviation threshold. The execution module is used to respond to the adjustment control signal, perform mechanical stimulation operation on the target carbon brush, and change the contact state between the target carbon brush and the slip ring.

[0071] Example 4, refer to Figure 3This is the fourth embodiment of the present invention, which differs from the previous three embodiments in that: if the function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0072] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0073] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0074] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0075] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A digital monitoring and maintenance system for excitation carbon brushes and slip rings, characterized in that: include, Acquire real-time current data from multiple carbon brushes to determine the degree of deviation of each carbon brush current from the reference current. Based on the generator operating parameters, determine the deviation threshold for judging abnormal carbon brush current; When the current deviation of the target carbon brush is detected to exceed the deviation threshold, an adjustment control signal is generated; In response to the adjustment control signal, a mechanical stimulation operation is performed on the target carbon brush to change the contact state between the target carbon brush and the slip ring.

2. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 1, characterized in that: Determining the degree of deviation of each carbon brush current from the reference current includes: Collect current data from multiple carbon brushes on the same slip ring; A reference current is calculated based on the current data of the multiple carbon brushes; the reference current is a statistical value of the current data of the multiple carbon brushes. Calculate the difference between the current value of each carbon brush and the reference current; The degree of deviation is determined based on the difference between the current value of each carbon brush and the reference current, and the rated parameters of the carbon brush.

3. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 2, characterized in that: The step of determining the deviation threshold for judging abnormal carbon brush current based on generator operating parameters includes: Obtain the excitation current and rotor speed of the generator; Consult the carbon brush current deviation comparison table based on the excitation current value and the rotor speed; Read the corresponding deviation threshold from the carbon brush current deviation lookup table; The carbon brush current deviation comparison table is established based on the wear pattern of carbon brushes under different excitation currents and speeds.

4. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 3, characterized in that: Read the corresponding deviation threshold from the carbon brush current deviation lookup table, including: Obtain the cumulative running time of the target carbon brush; Based on the excitation current value, the rotor speed, and the cumulative operating time, the deviation threshold is looked up from the carbon brush current deviation lookup table; The carbon brush current deviation reference table includes deviation thresholds set for carbon brushes with different usage durations. The deviation threshold for carbon brushes whose cumulative operating time exceeds a set proportion of their rated lifespan is greater than the deviation threshold for carbon brushes whose cumulative operating time does not exceed the set proportion.

5. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 4, characterized in that: Performing mechanical stimulation on the target carbon brush includes: Control the brush holder drive device associated with the target carbon brush; The brush holder is displaced by the brush holder drive device. The displacement change includes a first action that moves the carbon brush a first displacement distance away from the collector ring and a second action that moves the carbon brush a second displacement distance closer to the collector ring, wherein the first displacement distance and the second displacement distance are equal. The displacement change is repeated within a set time period.

6. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 5, characterized in that: Performing mechanical stimulation on the target carbon brush further includes: After performing the displacement change consisting of the first action and the second action, the real-time current value of the target carbon brush is obtained; The real-time current value is compared with the current value before the displacement change to determine the magnitude of the current change; If the current change amplitude is less than the change threshold, then in the next displacement change, both the first displacement distance and the second displacement distance will be adjusted to a set multiple of the current displacement distance; If the current change amplitude is greater than or equal to the change threshold and the current deviation of the target carbon brush drops below the deviation threshold, then the current first displacement distance and second displacement distance are maintained and the process continues until the set number of times is completed; If, after performing a set number of displacement changes, the current deviation of the target carbon brush still exceeds the deviation threshold, the target carbon brush is marked as an abnormal carbon brush and the physical location identifier of the target carbon brush is output.

7. The digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in claim 6, characterized in that: The generation of the regulation control signal includes graded judgment conditions: Acquire the temperature data of the target carbon brush and the arc intensity data of the corresponding slip ring region; If the temperature data is lower than the first temperature threshold, the adjustment control signal is generated directly. If the temperature data is between the first temperature threshold and the second temperature threshold, the adjustment control signal is generated when the arc intensity data is lower than the arc threshold, and the generation of the adjustment control signal is prohibited when the arc intensity data is higher than the arc threshold. If the temperature data is higher than the second temperature threshold, the generation of the adjustment control signal is prohibited and a high temperature alarm message is output.

8. A digital monitoring and maintenance method for excitation carbon brushes and slip rings, using a digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in any one of claims 1 to 7, characterized in that, include: The module comprises a current monitoring module, a threshold determination module, a control signal generation module, and an execution module, wherein: The current monitoring module is used to acquire real-time current data of multiple carbon brushes and determine the degree of deviation of the current of each carbon brush relative to the reference current. The threshold determination module is used to determine the deviation threshold for judging abnormal carbon brush current based on the generator operating condition parameters. The control signal generation module is used to generate an adjustment control signal when the detected current deviation of the target carbon brush exceeds the deviation threshold. The execution module is used to respond to the adjustment control signal, perform mechanical stimulation operation on the target carbon brush, and change the contact state between the target carbon brush and the slip ring.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the digital monitoring and maintenance system for excitation carbon brushes and slip rings as described in any one of claims 1 to 7.

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