Speed operation control method and system for steel belt strong-drive elevator

Abstract

The invention discloses a speed operation control method and system for a steel belt strong-drive elevator, and belongs to the technical field of elevator control. The method is applied to a steel belt strong-drive elevator speed operation control system comprising a host driving unit, a detection unit and a control unit. According to the method, initial parameter recording is triggered through a leveling signal detector, the angle increment and the real-time equivalent diameter of a traction wheel are calculated in real time in the ascending process of a lift car, and the rotating speed of a traction machine is optimized in real time based on a dynamic adjustment formula so as to maintain constant-speed running of the lift car; meanwhile, the deceleration elevator stopping process is controlled by presetting a deceleration position pulse value, parameters are dynamically adjusted in combination with crawling time, accurate leveling is achieved by adopting an S-shaped deceleration curve, and a layer height learning and exception handling mechanism is further included. According to the method, the problem that the equivalent diameter of the traction wheel is changed due to steel belt stacking and winding is solved, the speed fluctuation of the lift car is controlled within + / -0.2 m / min, the leveling precision reaches + / -1mm, the running stability and stopping accuracy of an elevator are remarkably improved, and the method is particularly suitable for an old building adding scene with the limited top floor height.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of elevator control technology, and in particular to a speed control method and system for a steel belt driven elevator. Background Art

[0002] Steel-belt-driven elevators, which use flat steel belts instead of traditional steel ropes, offer advantages such as compact structure and reduced hoistway space, and have broad application prospects in retrofitting elevators to older buildings. However, a core technical pain point lies in the fact that the steel belt is wound around the traction sheave in a superimposed winding pattern. As the car operates, the equivalent diameter of the traction sheave increases linearly with the number of steel belt turns (each turn increases by two times the steel belt thickness). If the traditional constant angular velocity control strategy is still used, the car linear velocity will increase simultaneously with the increase in equivalent diameter, resulting in speed fluctuations exceeding ±1.5 m / min, seriously affecting operational smoothness and the passenger experience.

[0003] At the same time, the existing control method has the following defects: First, the initial parameter records are easily affected by the leveling signal interference, resulting in the deviation of the equivalent diameter calculation benchmark; second, in the deceleration and elevator stop process, the deceleration position parameters need to be manually debugged repeatedly, which is inefficient and can easily cause the leveling accuracy to exceed ±5mm due to improper parameters; third, there is a lack of protection mechanism for abnormal situations such as excessive winding and jamming of steel belts, which poses a safety hazard; fourth, the long-term use of floor height data is prone to deviations due to the stretching of the steel belt, affecting the accuracy of position judgment.

[0004] These problems restrict the performance improvement and scenario adaptation of steel belt driven elevators. There is an urgent need for a speed control method that can dynamically compensate for equivalent diameter changes, optimize the elevator stopping process and provide abnormal protection. Summary of the Invention

[0005] The present invention provides a method and system for controlling the speed of a steel belt driven elevator. The technical solution is as follows: According to one aspect of the present application, a steel belt strong drive elevator speed operation control system is provided, the system comprising a main drive unit, a detection unit and a control unit; The main engine drive unit includes a traction wheel with a gradient circular structure and a flat steel belt, the contour curve of the traction wheel is a nested line, and the belt is wound on the traction wheel in a superimposed winding manner; The detection unit includes an encoder and a leveling signal detector. The encoder is installed on the traction machine corresponding to the traction wheel and is used to collect the angular position signal of the traction wheel to calculate the angle increment. The leveling signal detector is used to detect the bottom leveling signal and the top leveling signal of the car. The bottom leveling signal is used to indicate that the car is out of the bottom leveling when it jumps from the presence to the absence of the leveling signal, and the top leveling signal is used to indicate that the car is close to the top leveling when it jumps from the absence to the presence of the leveling signal. The control unit is electrically connected to the encoder and the leveling signal detector respectively, and is used to record the initial equivalent diameter and initial angle of the traction sheave when the car leaves the bottom leveling layer, and is also used to calculate the real-time equivalent diameter of the traction sheave according to the angle increment and adjust the real-time speed of the traction machine.

[0006] Optionally, the control unit calculates the real-time equivalent diameter D of the traction sheave n The formula is D n =D0+2×H×(θ / 360), where n is the real-time speed of the traction machine, θ is the angle increment relative to the initial angle θ0 acquired by the encoder, D0 is the initial equivalent diameter of the traction sheave, θ0 is the initial angle of the traction sheave, and H is the thickness of the steel belt; Each time the traction wheel rotates one circle, the increment of θ is 360 degrees, D n It increases linearly with the increase of θ.

[0007] Optionally, the control unit adjusts the real-time speed n of the traction machine as follows: n=n0×D0 / D n , where n0 is the ideal given speed when the elevator starts, and n varies with D n Increase proportionally to reduce, used to offset D n The impact of changes on the car linear speed.

[0008] Optionally, the deceleration and stopping process of the control unit includes an acceleration section, a constant speed section, a deceleration section, a crawling section and a stopping section; The control unit is preset with a deceleration position pulse value P d , when the pulse number of the encoder feedback reaches P d When the leveling signal detector detects that the top floor leveling signal jumps, the control unit triggers the stop section, decelerates the car speed to zero speed and completes the stop.

[0009] On the other hand, a speed control method for a steel belt driven elevator is provided, which is applied to a speed control system of a steel belt driven elevator, comprising: Step 1: When the car starts from the bottom floor, the leveling signal detector monitors the bottom floor leveling signal in real time. When the signal changes from being present to being absent, the control unit records the initial equivalent diameter D0 and initial angle θ0 of the traction sheave, and the encoder starts to collect the angle position signal. Step 2: During the upward movement of the car, the encoder feeds back the traction sheave angle position in real time. The control unit calculates the angle increment θ = θreal-time - θ0 and substitutes it into the formula D n =D0+2×H×(θ / 360), and the real-time equivalent diameter D is obtained. n ; Step 3: The control unit is based on the formula n=n0×D0 / D n , adjust the traction machine speed n in real time to maintain the car linear speed constant; Step 4: When the pulse number of the encoder feedback reaches the preset value P d When the traction machine enters the deceleration stage, the control unit controls the traction machine to enter the crawling stage after reducing the speed to the crawling speed; Step 5: When the leveling signal detector detects that the top leveling signal changes from zero to positive, the control unit triggers the stop section and controls the traction machine to decelerate to zero, completing the leveling.

[0010] Optionally, in step 4, the duration of the crawling segment is recorded as t, and the control unit automatically records and displays t; When t=0, determine P d If it is too large, the control unit will automatically reduce P d Avoid car collisions; When t>1 second, determine P d If it is too small, the control unit will automatically increase P d Improve operational efficiency and adjust the target to keep t within the range of 0.5 seconds to 1 second.

[0011] Optionally, in step 2, the accuracy of the angular position signal collected by the encoder is 0.1 degrees.

[0012] Optionally, in step 3, the adjustment frequency of the real-time rotation speed n is consistent with the encoder acquisition frequency.

[0013] Optionally, the method further includes a layer height learning step, including: The correspondence between the car position and floor height is established through the number of pulses fed back by the encoder.

[0014] The present invention provides a methanol-water solution automatic rehydration, preparation, detection, and control system for precisely controlling the methanol-water ratio and enabling automatic rehydration to improve the operating efficiency and stability of a methanol-to-hydrogen plant. The system comprises a raw material unit, a mixing unit, a storage unit, a rehydration unit, a detection unit, and a control unit. The raw material unit stores pure methanol and deionized water and monitors liquid level changes in real time using a liquid level sensor. The mixing unit uses a pump and a stirrer to precisely mix methanol and water in a set ratio. The storage unit stores the prepared methanol-water solution and delivers it to a reaction unit via a pump. The rehydration unit regulates the rehydration volume using a rehydration pump, a solenoid valve, and a relief valve to ensure timely replenishment of the methanol-water solution according to equipment needs. The detection unit monitors the status of the methanol-water solution in real time using concentration, level, temperature, and pressure sensors. The control unit receives signals from these sensors, processes the data, and adjusts the operating status of each system unit to ensure that the ratio, level, flow rate, temperature, and pressure of the methanol-water solution are always ideal. Through automated control and real-time feedback regulation, the present invention eliminates errors caused by manual operation, improves the efficiency of methanol-to-hydrogen plants, and improves hydrogen quality, thus offering broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 A schematic diagram of reducing the rotation speed of a main engine driven by a steel belt provided in this embodiment is shown; Figure 2 shows a running speed curve of a common traction ladder provided by this embodiment; Figure 3 The figure shows the optimized running speed curve of the steel belt strong drive elevator provided in this embodiment. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0018] In this document, "plurality" refers to two or more. "And / or" describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates an "or" relationship between the associated objects.

[0019] Example 1 According to one aspect of the present application, a steel belt strong drive elevator speed operation control system is provided, the system including a main drive unit, a detection unit and a control unit.

[0020] The main engine drive unit includes a traction wheel with a gradient circular structure and a flat steel belt. The contour curve of the traction wheel is a nested line and is wound on the traction wheel in an overlapping winding manner. The flat steel belt has a thickness of H = 3mm and a width of 30mm.

[0021] Among them, the trough line profile curve of the traction sheave meets the design of "the incremental radius of each circle is adapted to the thickness of the steel belt". Its curve equation is r(θ)=r0+(H / π)×(θ / 360), where r(θ) is the real-time radius when the traction sheave rotates by angle θ, r0 is the initial radius (r0=D0 / 2, D0 is the initial equivalent diameter), and H is the thickness of the steel belt (3mm). This curve makes the radius increment approximately 0.0083mm for every 1 degree of rotation of the traction sheave, ensuring that the steel belt fits tightly to the traction sheave contour when it is superimposed and wound, without slipping or gaps, avoiding deviations in equivalent diameter calculation caused by steel belt misalignment, and at the same time reducing friction loss between the steel belt and the traction sheave, extending the service life of the steel belt to more than 1.5 times that of traditional steel wire ropes.

[0022] The detection unit includes an encoder and a leveling signal detector. The encoder is installed on the traction machine corresponding to the traction wheel and is used to collect the angular position signal of the traction wheel to calculate the angle increment; the leveling signal detector is used to detect the bottom leveling signal and the top leveling signal of the car. Among them, the bottom leveling signal is used to indicate that the car is out of the bottom leveling when it jumps from presence to absence, and the top leveling signal is used to indicate that the car is close to the top leveling when it jumps from absence to presence.

[0023] The control unit is electrically connected to the encoder and the leveling signal detector respectively, and is used to record the initial equivalent diameter and initial angle of the traction sheave when the car leaves the bottom leveling layer. It is also used to calculate the real-time equivalent diameter of the traction sheave according to the angle increment and adjust the real-time speed of the traction machine.

[0024] Among them, the encoder is a 16-bit absolute encoder with a resolution of 65536 pulses / turn and a sampling frequency of ≥50Hz. It is coaxially connected to the traction machine output shaft during installation, with a coaxiality error of ≤0.02mm, ensuring the accuracy of angular position signal acquisition; the leveling signal detector is a photoelectric leveling switch with a detection distance of 5-10mm and a response time of ≤1ms. It is installed on both sides of the car top and has an alignment error of ≤2mm with the leveling baffle in the shaft, ensuring accurate triggering of the jump from "presence to absence" of the bottom leveling signal and "presence to absence" of the top leveling signal, avoiding deviation in the recording of the initial equivalent diameter D0 and the initial angle θ0.

[0025] This embodiment of the application addresses the core pain points of steel-belt driven elevators through a system architecture design consisting of a "gradually variable circular grooved wire traction sheave + high-precision detection unit + intelligent control unit" (see Figure 2). Structurally, the sheave's grooved wire profile (r(θ) = r0 + (H / π) × (θ / 360)) precisely matches the thickness of the steel belt, ensuring smooth, slip-free winding and gap-free operation. This avoids deviations in equivalent diameter calculations caused by misaligned steel belts and reduces frictional losses, extending the service life of the steel belt by more than 1.5 times that of traditional wire ropes. The combination of a 16-bit absolute encoder (resolution 65,536 pulses / turn) and a photoelectric leveling switch (response time ≤ 1ms) limits angular position acquisition errors to within ±0.5 degrees, and achieves a leveling signal transition trigger accuracy of ±2mm, providing a reliable data foundation for subsequent speed calculation and elevator stop control. At the functional level, the control unit establishes the correlation logic of "steel belt winding status-traction sheave parameters-car operation" by real-time recording the initial equivalent diameter D0 and the initial angle θ0, avoiding the problem of "equivalent diameter change leading to speed fluctuation" in traditional constant angular velocity control from the source. At the same time, the system is adapted to 3mm thick and 30mm wide flat steel belts, which greatly reduces the traction sheave diameter (the initial diameter is only 180mm), meeting the installation requirements of old buildings with a top floor height of less than 2.8m. Compared with traditional wire rope elevators (requiring a top floor height of more than 3.5m), the shaft space occupancy is reduced by more than 20%, significantly improving the elevator's adaptability to different scenarios.

[0026] Example 2 Optionally, the control unit calculates the real-time equivalent diameter D of the traction sheave n The formula is D n =D0+2×H×(θ / 360), where n is the real-time speed of the traction machine, θ is the angle increment relative to the initial angle θ0 acquired by the encoder, D0 is the initial equivalent diameter of the traction sheave, θ0 is the initial angle of the traction sheave, and H is the thickness of the steel belt. For each rotation of the traction sheave, the increment of θ is 360 degrees, and D n It increases linearly with the increase of θ.

[0027] Among them, D n =D0+2×H×(θ / 360) The derivation of the formula is based on the physical principle that "when the steel belt is wound in a superimposed manner, each turn of the steel belt increases the equivalent diameter of the traction sheave by 2 times the thickness of the steel belt". The steel belt is wound in a stacked manner. With each turn, the outer diameter of the traction sheave increases by one layer of steel belt thickness (the inner side adheres to the original wheel surface, and the outer side adds a thickness of H). Therefore, the equivalent diameter increment is 2H. The applicable boundary conditions of this formula are "θ≤θ max", where θmax is the maximum allowable rotation angle of the traction wheel, which is determined by the maximum number of steel belt layers that the traction wheel can accommodate. Taking D0=180mm, traction wheel width=80mm, and steel belt width=30mm as an example, the traction wheel can be wrapped with 2 layers of steel belt (total width 60mm≤80mm), θ max =720 degrees (2 turns), at this time the maximum equivalent diameter D max =180+2×3×(720 / 360)=192mm, to avoid the risk of the steel belt coming off the wheel due to excessive winding.

[0028] Optionally, the control unit adjusts the real-time speed n of the traction machine as follows: n=n0×D0 / D n , where n0 is the ideal given speed when the elevator starts, and n varies with D n Increase proportionally to reduce, used to offset D n The impact of changes on the car linear speed.

[0029] In an example, taking the ideal given speed of the elevator n0=1500rpm, D0=180mm, H=3mm as an example, when the traction wheel rotates 1 circle (θ=360 degrees), D n =180+2×3×(360 / 360)=186mm, real-time speed n=1500×180 / 186≈1451rpm; when rotating 2 circles (θ=720 degrees), D n =192mm, n=1500×180 / 192≈1406rpm; through speed adjustment, the car linear speed is always maintained at v=π×D0×n0 / 60=π×0.18×1500 / 60≈14.14m / min, and the speed fluctuation amplitude is ≤±0.2m / min, which is much lower than the ±1.5m / min fluctuation amplitude of traditional constant angular velocity control, verifying the effect of this formula on improving speed smoothness.

[0030] The embodiment of the present application realizes the precise control of the uniform speed operation of the steel belt driven elevator car by constructing a mathematical model of "real-time equivalent diameter calculation-dynamic speed adjustment". The technical effect can be quantitatively analyzed from the two aspects of calculation accuracy and speed stability. n =D0+2×H×(θ / 360) The formula is based on the physical principle that "each turn of the steel belt increases the equivalent diameter by 2H", combined with the maximum allowable rotation angle of the traction sheave θ max (720 degrees) boundary constraint ensures that the equivalent diameter calculation error is ≤±0.3mm, avoiding the risk of wheel off caused by excessive winding; taking D0=180mm and H=3mm as an example, when the traction wheel rotates 2 circles, D n The calculated value is 192mm, and the actual measured value is 191.8mm, with an error of only 0.1%, which verifies the accuracy of the formula. In terms of speed stability, n=n0×D0 / Dn The speed adjustment formula can offset the influence of the equivalent diameter change in real time. When n0=1500rpm, the traction wheel rotates 1 circle (D n =186mm) is adjusted to 1451rpm, and rotated 2 circles (D n =192mm) is adjusted to 1406rpm. The car linear speed is always stable at around 14.14m / min, with a fluctuation range of ≤±0.2m / min, which is much better than the ±1.5m / min fluctuation range of traditional constant angular velocity control. Passengers do not feel any obvious jerk. At the same time, the speed adjustment frequency is consistent with the encoder acquisition frequency (≥50Hz), avoiding speed mutations caused by adjustment lag, further improving operation smoothness, and solving the speed control problem caused by superimposed winding of steel belts.

[0031] Example 3 Optional, such as Figure 1 The diagram shows the reduction of the speed of the steel belt driven main engine, which controls the deceleration and elevator stopping process of the control unit, including the acceleration section, constant speed section, deceleration section, creeping section and stopping section.

[0032] The control unit has a preset deceleration position pulse value P d , when the pulse number of encoder feedback reaches P d When the leveling signal detector detects a jump in the top floor leveling signal, the control unit triggers the stop section, decelerating the car to zero speed to complete the stop.

[0033] In a possible implementation, the creeping speed is set to 0.2-0.3 m / min, which satisfies both the accuracy of leveling (avoiding high-speed rushing) and the operating efficiency (avoiding long waiting time caused by too low speed); the deceleration position pulse value P d The initial value of the d =Total running pulse number - P deceleration pulse number" setting, where the total running pulse number is the total pulse feedback value of the encoder from the bottom to the top of the car, and the P deceleration pulse number is the number of pulses required for the traction machine to decelerate from a constant speed to a creeping speed. Taking the pulse frequency corresponding to the constant speed = 10000 pulses / minute and the deceleration time = 2 seconds as an example, the P deceleration pulse number = 10000×(2 / 60)≈333 pulses. If the total running pulse number = 5000 pulses, then the initial value of Pd = 5000-333=4667 pulses, which is the subsequent P d Adjustments provide a benchmark.

[0034] Considering abnormal situations, the control unit has built-in P d Automatic adjustment algorithm, when the climbing time t of three consecutive stops is less than 0.5 seconds, the algorithm automatically adjusts P dReduce 50 pulses; when t is > 1 second for 3 consecutive times, P d Increase by 50 pulses until t stabilizes in the range of 0.5-1 second; if the abnormal situation of "the leveling signal is not triggered but the number of encoder pulses has reached the maximum value" occurs, the control unit immediately triggers emergency deceleration, reduces the car speed to 0.1m / min and issues an alarm signal, and records the P at the time of the fault. d value and angle increment, which is convenient for operation and maintenance personnel to check the fault of leveling signal detector or P d Setting bias problem.

[0035] In one example, a steel belt driven elevator was installed in an old building. The top floor height of the shaft was only 2.8m (traditional elevators require more than 3.5m). After applying this system, the following results were achieved.

[0036] The traction sheave adopts a dented line gradient circle structure, with its diameter increased from 180mm to 192mm, without increasing the shaft space. When the car is ascending, the speed fluctuation is ≤±0.2m / min through real-time adjustment of Dn and n, and passengers do not feel any obvious jerk. When decelerating to stop, the initial value of Pd is set to 4667 pulses. The first stop is t=0.3 seconds (<0.5 seconds). The system automatically reduces Pd to 4617 pulses, and the second stop is t=0.7 seconds (meets the requirements). Subsequent stops are stable at 0.6-0.8 seconds. The leveling accuracy is ≤±2mm, meeting the usage requirements.

[0037] Therefore, combined Figure 1 Further, Figure 1 The figure shows the speed difference between the steel belt driven elevator and the traditional traction elevator, and the control effect of this solution, with the running time t as the horizontal axis and the speed (unit: rpm) as the vertical axis. The figure contains two core curves. One is the "ideal speed curve of the traction elevator", which is a standard trapezoid and represents the speed change of the traditional traction elevator (with a fixed traction sheave diameter) - the speed rises rapidly in the acceleration section, maintains a constant speed in the uniform speed section, and drops rapidly in the deceleration section. The speed can maintain a uniform speed of the car without adjusting the speed throughout the whole process; the other is the "actual given speed curve of the steel belt driven elevator", the trend of which is basically the same as the ideal curve in the acceleration and deceleration sections. The key difference is reflected in the uniform speed section: as the car goes up, the steel belt is superimposed and wrapped around the traction sheave, and the equivalent diameter D of the traction sheave is reduced. n According to the formula "D n =D0+2×H×(θ / 360)” increases linearly to offset D nTo understand the impact of changes in speed on the car linear speed, the control unit adjusts the traction machine speed in real time according to the formula "n=n0×D0 / Dn", so that the curve shows a slow downward trend in the uniform speed section (for example, taking D0=180mm, H=3mm, and n0=1500rpm as an example, the speed drops to about 0.882n0 after the traction wheel rotates 4 times). The comparison of the two curves directly verifies the necessity and effectiveness of the "dynamic adjustment of speed to maintain uniform car speed" solution of this embodiment, which not only reflects the advantages of steel belt driven elevators due to D n The particularity of speed control caused by the change also proves that adjusting the speed through the formula can make the actual speed fit the ideal linear speed requirement and avoid speed fluctuations.

[0038] Combine Figure 2 , a common traction ladder running speed curve is given as a comparison with the solution of embodiment 3. Figure 2 As a comparison benchmark, the standard speed variation of a conventional traction elevator (with a fixed sheave diameter) is illustrated, with travel time as the horizontal axis and car speed as the vertical axis. The speed curve in the figure includes only three phases: acceleration, uniform speed, and deceleration. During the acceleration phase, the car speed rapidly increases from 0 to the rated uniform speed at a fixed acceleration, corresponding to a synchronous and constant increase in the traction motor speed. During the uniform speed phase, because the traction sheave diameter remains unchanged, the traction motor maintains a constant speed, ensuring stable car speed, resulting in a horizontal curve. During the deceleration phase, the speed rapidly decreases from the rated uniform speed to 0 at a fixed deceleration, allowing the car to stop. The simplicity of this curve stems from the fact that conventional traction elevators can accurately infer the actual car speed and position from encoder feedback of angular velocity, allowing accurate stopping without requiring additional transition phases. This characteristic highlights the technical necessity for optimizing the stopping process in steel belt-driven elevators, where the initial equivalent diameter D0 of the traction sheave is unknown and the speed and position cannot be directly inferred from the encoder. This provides a comparative reference for the stopping solution proposed in this embodiment.

[0039] Combine Figure 3 , gives the diagram of the optimized deceleration and elevator stop process, through Figure 3The optimized running speed curve of the steel belt driven elevator is fully presented, with the running time as the horizontal axis and the car speed as the vertical axis. On the basis of the "acceleration section, uniform speed section, and deceleration section" of ordinary traction elevators, the "creeping section and stopping section" are added to form a five-stage speed control logic. Specifically, the trends of the acceleration section and the uniform speed section are consistent with those of ordinary traction elevators. The uniform speed section can maintain a stable speed by adjusting the traction machine speed in real time; when the encoder feedback pulse number accumulates to the preset deceleration position pulse value Pd, it enters the deceleration section, and the car speed drops from the rated uniform speed value to the preset crawling speed (usually 0.2-0.3m / min); then it enters the crawling section, maintaining a stable crawling speed until the leveling signal detector detects a jump from "nothing to something" in the top leveling signal; finally, it enters the stopping section, and the car speed drops from the crawling speed to 0, and the impact of elevator stop is avoided by optimizing the deceleration curve. The diagram also shows the prompt "adjust the deceleration position backward", indicating that when the duration t of the crawling segment is too long, the deceleration start time can be delayed by increasing Pd, so that the crawling segment can better meet the leveling requirements. This reflects the core design of "adding crawling segments + dynamically adjusting Pd" to solve the leveling problem of steel belt driven elevators, and also provides visual operation guidance for actual debugging.

[0040] The embodiment of the present application optimizes the deceleration and stopping process (adding a crawling section + P d Dynamic adjustment) takes into account the leveling accuracy, operating efficiency and safety of steel belt driven elevators. The technical effect can be reflected in three aspects: elevator stopping accuracy, operating efficiency and fault protection. In terms of leveling accuracy, the crawling speed design of 0.2-0.3m / min, combined with the precise triggering of the leveling signal detector (detection distance 5-10mm), makes the leveling accuracy ≤±2mm, meeting the leveling error standard of the elevator industry; d The initial value is set according to "total running pulse number - P deceleration pulse number" (for example, when the total pulse is 5000, the initial P d =4667), combined with an automatic adjustment algorithm (±50 pulses for three consecutive t abnormalities), the crawl time t can be quickly stabilized within the range of 0.5-1 second, avoiding the blindness of manual debugging and improving debugging efficiency by over 60%. In terms of operational efficiency, when t is controlled within the target range, the total time from deceleration to stop of the elevator is shortened by 0.3-0.5 seconds compared to the "excessively long crawl" scenario (t>1 second), and the single-trip efficiency is improved by 8%-12%, making it particularly suitable for high-frequency use scenarios in high-rise residential elevators. In terms of safety, in the event of an abnormal situation where the "leveling signal is not triggered," the control unit can immediately trigger emergency deceleration (speed is reduced to 0.1m / min) and alarm, while also recording fault data, reducing the risk of floor collisions. Compared with traditional elevator stop processes without abnormal protection, the safety factor is increased by more than three times, fully solving the leveling control problem caused by the unknown equivalent diameter of steel belt driven elevators.

[0041] Example 4 On the other hand, a speed control method for a steel belt driven elevator is provided, which is applied to a speed control system of a steel belt driven elevator, comprising: Step 1: When the car starts from the bottom floor, the leveling signal detector monitors the bottom floor leveling signal in real time. When the signal changes from being present to being absent, the control unit records the initial equivalent diameter D0 and initial angle θ0 of the traction sheave, and the encoder starts to collect the angle position signal.

[0042] When the leveling signal detector monitors the bottom leveling signal, it needs to detect the "from presence to absence" jump three times in a row (interval ≤ 100ms) before the control unit determines that the car has truly left the bottom leveling floor, avoiding the incorrect recording of D0 and θ0 caused by single signal interference; at the same time, the control unit has a built-in initial parameter calibration function. When the elevator is started for the first time each day, it automatically controls the car to go back and forth at the bottom leveling position once, and compares the D0 deviation recorded when leaving the floor twice (the allowable deviation is ≤ 0.5mm). If the deviation exceeds the threshold, the encoder zero point calibration is triggered to ensure the accuracy of D0 and θ0 recording, providing a reliable benchmark for subsequent calculations.

[0043] Step 2: During the upward movement of the car, the encoder feeds back the traction sheave angle position in real time. The control unit calculates the angle increment θ = θreal-time - θ0 and substitutes it into the formula D n =D0+2×H×(θ / 360), and the real-time equivalent diameter D is obtained. n .

[0044] Optionally, in step 2, the accuracy of the angular position signal collected by the encoder is 0.1 degrees. After the encoder collects the angular position signal, the control unit first corrects θrealtime through a "sliding average filter" (taking the average of five consecutive collected values), then calculates θ=θrealtime-θ0, controlling the angle increment calculation error within ±0.1 degrees. Simultaneously, the control unit presets a maximum Dn threshold Dn_max (Dn_max=D0+2×H×N_max, where N_max is the maximum allowable number of windings of the traction sheave, determined by the steel belt width and the traction sheave width. For example, if the steel belt width is 30 mm and the traction sheave width is 80 mm, N_max=2 turns, and Dn_max=D0+12 mm). When the calculated Dn ≥ Dn_max, the control unit immediately issues an alarm and restricts the traction sheave from further rotation to prevent the steel belt from excessively winding and derailing.

[0045] Step 3: The control unit is based on the formula n=n0×D0 / D n , adjust the traction machine speed n in real time to maintain the car linear speed constant.

[0046] Optionally, in step 3, the adjustment frequency of the real-time speed n is consistent with the encoder acquisition frequency. The adjustment frequency of the real-time speed n is consistent with the encoder acquisition frequency (≥50Hz), and the control unit adopts an "incremental adjustment" strategy - after each calculation of Dn, the speed n is only fine-tuned by ±5rpm (to avoid sudden changes in speed). At the same time, the car speed feedback signal is collected in real time (via an additionally installed car speed sensor). When the car linear speed fluctuation exceeds ±0.1m / min, the speed adjustment range is automatically increased (±10rpm) to quickly compensate for the speed deviation. For example, when the calculated n should be 1451rpm but the actual car speed is 0.15m / min lower, the control unit adjusts the speed to 1461rpm, and the speed can return to the target value within one acquisition cycle.

[0047] Step 4: When the pulse number of the encoder feedback reaches the preset value P d When the traction machine enters the deceleration stage, the control unit controls the traction machine to enter the deceleration stage, reduces the speed to the crawling speed and then enters the crawling stage.

[0048] Optionally, in step 4, the duration of the crawling segment is recorded as t, and the control unit automatically records and displays t.

[0049] When t=0, determine P d If it is too large, the control unit will automatically reduce P d Avoid car rushing to the floor; when t>1 second, determine P d If it is too small, the control unit will automatically increase P d Improve operational efficiency and adjust the target to keep t within the range of 0.5 seconds to 1 second.

[0050] In summary, when the control unit automatically adjusts Pd, it adopts the "gradient adjustment" logic - when adjusting Pd for the first time, it is adjusted according to the amplitude of ±50 pulses; if t still exceeds the range of 0.5-1 second after adjustment, the second adjustment amplitude is reduced to ±30 pulses; the third and subsequent adjustments are fine-tuned according to ±20 pulses to avoid t repeatedly exceeding the target range due to large-scale adjustments; at the same time, the control unit in the crawling section monitors the traction wheel current in real time. When the current exceeds 1.2 times the rated value (indicating that the steel belt is stuck), the crawling speed is immediately reduced to 0.1m / min and an alarm is issued. After the current returns to normal, the original crawling speed is restored to prevent overload and damage to the steel belt.

[0051] Step 5: When the leveling signal detector detects that the top leveling signal changes from zero to positive, the control unit triggers the stop section and controls the traction machine to decelerate to zero, completing the leveling.

[0052] The stopping section adopts an "S-shaped deceleration curve" (rather than linear deceleration), with the deceleration acceleration gradually decreasing from 0.5m / s² to 0, to avoid the impact when the car stops. After leveling, the control unit compares the actual position of the car with the leveling reference position (determined by the leveling signal detector). If the deviation exceeds ±2mm, the traction motor is automatically controlled to fine-tune the car position at a speed of 0.05m / min until the deviation is ≤±1mm, achieving the dual protection of "precise stopping + secondary calibration". For example, if the car is detected to be 3mm above the ground after leveling, the control unit controls the traction motor to reverse, causing the car to slowly move down 3mm to complete the calibration.

[0053] Optionally, the method further includes a floor height learning step, in which a correspondence between the car position and the floor height is established through the number of pulses fed back by the encoder.

[0054] During the floor height learning step, the control unit automatically updates the correspondence between the car position and floor height (overwriting old data) after each round trip between the bottom floor and the top floor, avoiding position deviation caused by steel belt stretching during long-term operation; when it detects that the number of pulses corresponding to a certain floor height changes by more than 5% (indicating data abnormality), the re-learning process is automatically triggered, and the abnormal data is uploaded to the elevator monitoring platform to remind the operation and maintenance personnel to check the steel belt tension; for example, the original number of pulses corresponding to the 3rd floor is 3000, and after a certain learning, it becomes 3160 (a change of 5.3%), and the system immediately re-learns and issues an alarm.

[0055] The control method provided in the embodiment of the present application systematically solves the speed control problem of steel belt driven elevators through the full process design of "dynamic parameter calculation-real-time speed adjustment-intelligent elevator stop optimization". In terms of speed stability, the sliding average filter is used to correct the angle signal, combined with the ±5rpm incremental speed adjustment strategy, and cooperated with the car speed feedback compensation to reduce the linear speed fluctuation from the traditional method of ±1.5m / min to ±0.2m / min, and passengers do not feel obvious jerkiness; the initial parameters are confirmed by three signals and calibrated daily to ensure that the D0 and θ0 recording errors are ≤0.5mm, laying the foundation for accurate calculation. In terms of leveling accuracy, the S-shaped deceleration curve is combined with the ±1mm secondary calibration mechanism after leveling, which reduces the impact of elevator stops by 60% and improves the leveling accuracy to ±1mm; the Pd parameter is adjusted by gradient (50→30→20 pulses), which is 3 times more efficient than manual debugging, and the crawling time is stabilized in the optimal range of 0.5-1 seconds. In terms of safety and reliability, the Dn boundary limitation, crawling section current monitoring, and dynamic update of floor height data functions respectively avoid the risks of excessive steel belt winding, jamming, and position deviation, reducing the elevator failure downtime rate by 40%. This is especially suitable for old buildings with top-floor heights of less than 2.8 meters, reflecting the synergistic improvement of the method in accuracy, efficiency, and safety.

[0056] An embodiment of the present application further provides a computer-readable medium storing at least one instruction, which is loaded and executed by a processor to implement the steel belt driven elevator speed control method of each embodiment above.

[0057] The above description is merely an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A steel belt driven elevator speed control system, characterized in that: The system includes a host drive unit, a detection unit and a control unit; The main engine drive unit includes a traction wheel with a gradient circular structure and a flat steel belt, the contour curve of the traction wheel is a nested line, and the belt is wound on the traction wheel in a superimposed winding manner; The detection unit includes an encoder and a leveling signal detector. The encoder is installed on the traction machine corresponding to the traction wheel and is used to collect the angular position signal of the traction wheel to calculate the angle increment. The leveling signal detector is used to detect the bottom leveling signal and the top leveling signal of the car. The bottom leveling signal is used to indicate that the car is out of the bottom leveling when it jumps from the presence to the absence of the leveling signal, and the top leveling signal is used to indicate that the car is close to the top leveling when it jumps from the absence to the presence of the leveling signal. The control unit is electrically connected to the encoder and the leveling signal detector respectively, and is used to record the initial equivalent diameter and initial angle of the traction sheave when the car leaves the bottom leveling layer, and is also used to calculate the real-time equivalent diameter of the traction sheave according to the angle increment and adjust the real-time speed of the traction machine.

2. The steel belt driven elevator speed control system according to claim 1 is characterized in that: The control unit calculates the real-time equivalent diameter D of the traction sheave n The formula is D n =D0+2×H×(θ / 360), where n is the real-time speed of the traction machine, θ is the angle increment relative to the initial angle θ0 acquired by the encoder, D0 is the initial equivalent diameter of the traction sheave, θ0 is the initial angle of the traction sheave, and H is the thickness of the steel belt; Each time the traction wheel rotates one circle, the increment of θ is 360 degrees, D n It increases linearly with the increase of θ.

3. The steel belt driven elevator speed control system according to claim 1 is characterized in that: The formula for the control unit to adjust the real-time speed n of the traction machine is n=n0×D0 / D n , where n0 is the ideal given speed when the elevator starts, and n varies with D n Increase proportionally to reduce, used to offset D n The impact of changes on the car linear speed.

4. The steel belt driven elevator speed control system according to claim 1 is characterized in that: The deceleration and stopping process of the control unit includes an acceleration section, a constant speed section, a deceleration section, a crawling section and a stopping section; The control unit is preset with a deceleration position pulse value P d , when the pulse number of the encoder feedback reaches P d When the leveling signal detector detects that the top floor leveling signal jumps, the control unit triggers the stop section, decelerates the car speed to zero speed and completes the stop.

5. A speed control method for a steel belt driven elevator, characterized in that: The steel belt driven elevator speed control system according to any one of claims 1 to 4 comprises: Step 1: When the car starts from the bottom floor, the leveling signal detector monitors the bottom floor leveling signal in real time. When the signal changes from being present to being absent, the control unit records the initial equivalent diameter D0 and initial angle θ0 of the traction sheave, and the encoder starts to collect the angle position signal. Step 2: During the upward movement of the car, the encoder feeds back the traction sheave angle position in real time. The control unit calculates the angle increment θ = θreal-time - θ0 and substitutes it into the formula D n =D0+2×H×(θ / 360), and the real-time equivalent diameter D is obtained. n ; Step 3: The control unit is based on the formula n=n0×D0 / D n , adjust the traction machine speed n in real time to maintain the car linear speed constant; Step 4: When the pulse number of the encoder feedback reaches the preset value P d When the traction machine enters the deceleration stage, the control unit controls the traction machine to enter the crawling stage after reducing the speed to the crawling speed; Step 5: When the leveling signal detector detects that the top leveling signal changes from zero to positive, the control unit triggers the stop section and controls the traction machine to decelerate to zero, completing the leveling.

6. The speed control method for a steel belt driven elevator according to claim 5, characterized in that: In step 4, the duration of the crawling segment is recorded as t, and the control unit automatically records and displays t; When t=0, determine P d If it is too large, the control unit will automatically reduce P d Avoid car collisions; When t>1 second, determine P d If it is too small, the control unit will automatically increase P d Improve operational efficiency and adjust the target to keep t within the range of 0.5 seconds to 1 second.

7. The speed control method for a steel belt driven elevator according to claim 5, characterized in that: In step 2, the accuracy of the angular position signal collected by the encoder is 0.1 degrees.

8. The speed control method for a steel belt driven elevator according to claim 5, characterized in that: In step 3, the adjustment frequency of the real-time speed n is consistent with the encoder acquisition frequency.

9. The speed control method for a steel belt driven elevator according to claim 5, characterized in that: The method further includes a layer height learning step, including: The correspondence between the car position and floor height is established through the number of pulses fed back by the encoder.

Images