An elevator drive control system

Abstract

The application discloses an elevator car driving control system, and belongs to the elevator technical field. The driving control system comprises a driving motor speed detector for detecting the rotating speed of a driving motor of an elevator device, a driving motor current detector for detecting the current of the driving motor, a driving motor current controller for generating the expected torque of the driving motor according to the difference between the current instruction value and the current detection value of the driving motor, and a driving motor speed controller for generating the current instruction value of the driving motor according to the difference between the speed instruction value and the speed detection value of the driving motor, and further comprises a driving motor speed instruction generating unit for generating the speed instruction value of the driving motor according to the car speed instruction inputted from outside, the rotating detection value of the driving motor and the speed detection value of the elevator car. The technical scheme has the beneficial effects that the deformation amount of the flexible connecting body is included in the driving control cycle, and the driving control performance is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of elevators, and in particular to an elevator drive control system. Background Art

[0002] In existing technology, the elevator's drive motor is typically controlled to maintain stable speed control for passengers and ensure both passenger comfort and elevator efficiency. Traditional drive motor control utilizes the motor's mathematical model and employs a voltage-current dual-closed-loop variable-frequency vector speed control technology to regulate the motor's speed. This so-called dual-closed-loop variable-frequency speed control technology is based on the motor's mathematical model and uses feedback from the motor's speed detection value to adjust the motor's operating speed, thereby adjusting the elevator car's travel speed.

[0003] Taking traction elevator equipment as an example, the existing elevator structure is as follows Figure 1 As shown in FIG, which includes an elevator car 11, a traction sheave 12 and a counterweight device 13, the upper end of the elevator car 11 and one side of the traction sheave 12 ( Figure 1 The left side of the traction wheel 12 is connected by a flexible connector (such as a wire rope) 14, and the other side ( Figure 1 The upper end of the counterweight 13 is also connected to the right side of the elevator car 11 by a flexible connector, and the lower end of the counterweight 13 is connected to the lower end of the elevator car 11 by a compensating chain 15. If the elevator system is a non-traction elevator, that is, an elevator system controlled by a drive wheel, the main difference is that the counterweight 13 is removed, that is, the drive wheel is directly connected to the lower end of the elevator car.

[0004] Whether it is a traction elevator or a non-traction elevator, in the traditional double-closed-loop variable voltage and frequency speed regulation technology, the motor rotor, drive wheel / traction wheel, flexible connector, and elevator car are regarded as a whole (hereinafter referred to as the transmission assembly). The transmission assembly is rigidly connected, that is, the deformation of the internal connection is ignored, so that the rotor angular velocity of the drive motor is directly converted into the moving speed of the elevator car, or conversely, the speed detection value of the drive motor is directly converted according to the moving speed control instruction of the elevator car. On this basis, the speed detection value of the drive motor is used to realize the speed closed-loop control of the drive motor.

[0005] However, in actual operation, the internal connections of the aforementioned transmission assembly are not all rigid. A typical example is the flexible connector between the elevator car and the drive / traction sheave. The flexible connector itself has a certain elastic damping effect. During the operation of the elevator car, due to the tension generated by the elevator car and the drive / traction sheave, the flexible connector will produce a certain amount of elongation, that is, a certain amount of dynamic deformation. This will cause the input and output signals passing through the flexible connector to have a significant time delay, and the time domain and frequency domain characteristics of the input and output signals will be different. Therefore, if the aforementioned transmission assembly is treated as a rigidly connected whole to control the speed of the elevator car, the dynamic characteristics of the flexible connector itself will inevitably be ignored, resulting in a decrease in drive control performance. In particular, when the elastic modulus of the flexible connector is large, the elevator hoist height is large, and the elevator car is located at a low position (in this case, the length of the flexible connector between the elevator car and the drive / traction sheave is long), the dynamic deformation of the flexible connector is relatively large, which will have a significant impact on the speed control of the elevator car. From the perspective of the passenger experience, it is manifested as a more obvious vertical vibration of the elevator car during movement.

[0006] In the prior art, there are some technical solutions to solve the problem of vertical vibration of the elevator car. The more mainstream technical solution is to detect the absolute position of the elevator car, use the absolute position of the elevator car to obtain the moving speed of the elevator car, and then use the detected value of the moving speed of the elevator car to realize the speed closed-loop control of the elevator car. However, the controlled object of the speed closed-loop control should be a whole composed of the elevator drive motor and the above-mentioned transmission assembly. If only the elevator drive motor is considered as the controlled object (that is, only the moving speed of the elevator car is considered) when designing the speed control, and the influence of the transmission assembly (mainly the flexible connector) on the overall speed control of the elevator equipment is ignored, it will also lead to a decrease in the control performance of the speed closed-loop control, and it will not be able to eliminate the vertical vibration phenomenon during the operation of the elevator.

[0007] To address the issue of vertical vibration in elevator cars during operation, Japanese patent JP2004123256A discloses an elevator speed control device. This device calculates the vibration frequency of the elevator car based on the elevator car's detection value, load, and a signal component that matches the calculated car vibration frequency. It then removes the set car speed command value and outputs the result. Finally, the speed of the drive motor is controlled based on the output speed command value. This published patent primarily utilizes a notch filter to remove the elevator car's vibration frequency component from the overall speed command value, thereby suppressing the vertical vibration of the elevator car. However, this solution suffers from complex parameter calculations, making practical application difficult and costly.

[0008] Chinese patent CN112739637A discloses an elevator control device that suppresses elevator car vibration by superimposing a frequency component that suppresses the car's vibration on the speed command value. However, the technical solution in this published patent assumes two basic conditions: the first is that the transmission characteristic from the drive motor to the elevator car has a second-order delay factor, and the second is that the attenuation coefficient of the rope between the elevator car and the sheave is zero. These two assumptions negatively impact the final speed regulation performance, causing the application of this technical solution to negatively impact the closed-loop speed control of the elevator car.

[0009] The previously published document "Vertical-vibration control of elevators using estimated car acceleration feedback compensation" (IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 47, NO. 1, FEBRUARY 2000, P91-99) proposes using an extended full-order observer to observe the acceleration of the elevator car, filtering the speed command of the drive motor with a high-pass filter to obtain an acceleration command value, and then suppressing the vertical vibration of the elevator car through acceleration feedback control. While this technical solution superficially solves the problem of vertical vibration of the elevator car, it does not essentially implement the technical solution by analyzing the cause of the vertical vibration of the elevator car. Instead, it simply controls vibration through acceleration feedback. As a result, the actual control effect of this technical solution is heavily dependent on the accuracy of the observed car angular velocity results, and its actual control effect is very limited.

[0010] In summary, the existing technical solutions for solving the problem of vertical vibration of elevator cars do not involve in-depth analysis of the causes of the vertical vibration of the elevator car, nor do they eliminate the vibration from the root. Instead, they only feed back, filter and adjust the signal based on the appearance of the vibration. Naturally, the actual control effect is unsatisfactory. Summary of the Invention

[0011] Based on the above technical problems, the present invention aims to provide a technical solution for an elevator drive control system, in which the elevator car and the flexible connector connecting the elevator car are respectively used as controlled objects to design a drive controller, thereby incorporating the dynamic deformation of the flexible connector into the closed-loop drive control cycle, thereby improving the drive control performance of the elevator car.

[0012] The above technical solutions specifically include:

[0013] An elevator drive control system, applied to an elevator device, the elevator device comprising an elevator car, a counterweight device, a drive wheel, and a flexible connector connecting the elevator car and the counterweight device and suspended on the drive wheel, the drive control system comprising: a drive motor speed detector for detecting the speed of a drive motor of the elevator device, a drive motor current detector for detecting the current of the drive motor, a drive motor current controller for generating a desired torque of the drive motor based on a difference between a current command value of the drive motor and a current detection value, and a drive motor speed controller for generating the current command value of the drive motor based on a difference between a speed command value of the drive motor and a speed detection value; wherein the drive control system further comprises:

[0014] A drive motor speed command generating unit generates a speed command value for the drive motor based on an externally input car speed command, a rotation detection value of the drive motor, and a speed detection value of the elevator car.

[0015] Preferably, the elevator drive control system, wherein the drive control system further comprises:

[0016] A compensation torque generating unit is configured to generate a compensation torque according to a speed detection value of the drive motor, a speed detection value of the elevator car, and a mass of the flexible connector;

[0017] Compensation unit: Compensates the desired torque output by the drive motor current controller using at least the compensation torque output by the compensation torque generation unit to obtain a final drive motor torque instruction.

[0018] Preferably, in the elevator drive control system, the compensation unit uses the sum of the compensation torque output by the compensation torque generating unit and the desired torque of the drive motor as the final drive motor torque instruction;

[0019] or

[0020] The compensation unit first calculates the sum of the compensation torque output by the compensation torque generation unit and the desired torque of the drive motor as a preliminary result, then calculates the difference between the preliminary result and the torque generated by the counterweight device, and uses the obtained difference as the final drive motor torque instruction.

[0021] Preferably, in the elevator drive control system, the compensation torque generating unit further comprises:

[0022] A first force generating module is configured to generate a first force between the flexible connector and the elevator car according to a speed detection value of the drive motor and a speed detection value of the elevator car;

[0023] A first calculation module is configured to calculate the gravity exerted on the flexible connector according to the position of the elevator car and the linear density of the flexible connector;

[0024] A second calculation module is configured to calculate the sum of the gravity of the flexible connector and the first force as a first intermediate result, then calculate the product of the mass of the flexible connector and the equivalent acceleration of the flexible connector as a second intermediate result, and finally calculate and output the difference between the first intermediate result and the second intermediate result;

[0025] A third calculation module is configured to calculate the product of the output result of the second calculation module and the radius of the driving wheel and use the product as the compensation torque.

[0026] Preferably, in the elevator drive control system, the drive motor speed instruction generating unit further comprises:

[0027] A first force generating module is configured to generate a first force between the flexible connector and the elevator car according to a speed detection value of the drive motor and a speed detection value of the elevator car;

[0028] A car speed controller generates a command value of the first acting force according to an externally input speed command value of the elevator car and a speed detection value of the elevator car;

[0029] Flexible connector deformation controller: generates a speed instruction value for the drive motor according to the instruction value for the first force and the first force output by the first force generation module.

[0030] Preferably, in the elevator drive control system, the first force generating module further comprises:

[0031] Spring force calculation submodule: calculates the spring force of the flexible connector according to the elongation deformation of the flexible connector;

[0032] Resistance calculation submodule: calculates the resistance of the flexible connector according to the speed of the flexible connector's elongation and deformation;

[0033] The difference calculation submodule is used to output the difference between the spring force and the resistance as the first action force.

[0034] Preferably, in the elevator drive control system, the first force generating module further comprises:

[0035] Spring force calculation submodule: calculates the spring force of the flexible connector according to the elongation deformation of the flexible connector;

[0036] Resistance calculation submodule: calculates the resistance of the flexible connector according to the speed of the flexible connector's elongation and deformation;

[0037] The difference calculation submodule is used to output the difference between the spring force and the resistance as the first action force.

[0038] Preferably, in the elevator drive control system, the spring force calculation submodule calculates the spring force of the flexible connector according to the following formula:

[0039]

[0040] in,

[0041] ΔL(x) is used to represent the sum of the elongation deformation of the flexible connection body between the driving wheel and the position x of the infinitesimal element dx on the flexible connection body;

[0042] F 弹 Used to represent the spring force exerted on the microelement dx on the flexible connector;

[0043] E is used to represent the elastic modulus of the flexible connector;

[0044] ΔL(x) is calculated by the difference between the rotation detection value of the drive motor and the speed detection value of the elevator car.

[0045] Preferably, in the elevator drive control system, the resistance calculation submodule calculates the resistance of the flexible connector according to the following formula:

[0046]

[0047] in,

[0048] F 阻 Used to represent the resistance of the flexible connector;

[0049] ΔL is used to represent the sum of the elongation deformations of the flexible connector;

[0050] c represents the damping coefficient of the flexible connector.

[0051] Preferably, in the elevator drive control system, the control object of the flexible connector deformation controller is the flexible connector located between the drive wheel and the elevator car, and the mathematical model of the flexible connector is constructed as follows:

[0052]

[0053] in,

[0054] ΔL(x) is used to represent the sum of the elongation deformation of the flexible connection body between the driving wheel and the position x of the infinitesimal element dx on the flexible connection body;

[0055] F 弹 Used to represent the spring force exerted on the microelement dx on the flexible connector;

[0056] E is used to represent the elastic modulus of the flexible connector;

[0057] ΔL(x) is calculated by the difference between the rotation detection value of the drive motor and the speed detection value of the elevator car;

[0058] F 阻 Used to represent the resistance of the flexible connector;

[0059] ΔL is used to represent the total elongation deformation of the flexible connector;

[0060] c represents the damping coefficient of the flexible connector;

[0061] F2 is used to represent the first acting force.

[0062] Preferably, in the elevator drive control system, the difference between the acceleration of the elevator car and the linear acceleration of the drive wheel at a current moment is used as the equivalent acceleration of the flexible connector at a next moment.

[0063] The beneficial effect of the above technical solution is: the elevator car and the flexible connector connecting the elevator car are respectively used as controlled objects to design the drive control system, so that the dynamic deformation of the flexible connector is included in the closed-loop drive control cycle, thereby improving the drive control performance of the elevator car. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is a structural diagram of an elevator device in the prior art;

[0065] Figure 2 It is a schematic diagram of an elevator drive control system in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0066] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0067] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0068] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0069] Based on the problems existing in the prior art mentioned above, in the technical solution of the present invention, the elevator car, flexible connector, drive wheel / traction wheel and motor rotor are no longer regarded as an integral transmission combination. Instead, the elevator car and flexible connector are respectively regarded as controlled objects to design the drive control method, thereby obtaining the drive control instructions of the elevator car.

[0070] In a preferred embodiment of the present invention, an elevator drive control system is provided, which is applied to an elevator device, such as Figure 1 As shown in the figure, it includes an elevator car 11 and a drive wheel (such as a traction wheel 12 in a traction elevator), a flexible connector 14 (such as a steel rope) is connected between the upper end of the elevator car 11 and the drive wheel, and a compensation chain 15 is connected between the lower end of the elevator car 11 and the drive wheel 12.

[0071] Then Figure 2 As shown in , the elevator drive control system includes a drive motor speed detector 21 for detecting the speed of the drive motor of the elevator device, a drive motor current detector 22 for detecting the current of the drive motor, a drive motor current controller 23 for generating the desired torque of the drive motor based on the difference between the current command value and the current detection value of the drive motor, and a drive motor speed controller 24 for generating the current command value of the drive motor based on the difference between the speed command value and the speed detection value of the drive motor. The drive motor speed detector 21, drive motor current detector 22, drive motor current controller 23, and drive motor speed controller 24 are implemented using traditional voltage-current dual closed-loop variable-voltage and variable-frequency vector speed control technology, and will not be described in detail here.

[0072] In the present invention, the elevator drive control system further comprises a drive motor speed command generating unit, which generates a speed command value of the drive motor according to an externally input car speed command, a rotation detection value of the drive motor and a speed detection value of the elevator car.

[0073] Furthermore, if Figure 2 As shown in , the above-mentioned drive motor speed instruction generating unit further includes:

[0074] A first force generating module: generating a first force between the flexible connector and the elevator car according to a speed detection value of the drive motor and a speed detection value of the elevator car;

[0075] Car speed controller 25: generates a first force command value according to an externally input car speed command value and a car speed detection value;

[0076] The flexible connection body deformation controller 26 generates a speed instruction value for the driving motor according to the instruction value of the first force and the first force output by the first force generation module.

[0077] Specifically, a force analysis of the elevator car shows that the forces acting on the elevator car during operation include: the downward pull on the elevator car caused by the gravity of the compensation chain 15 connected to the lower end of the elevator car due to its own mass, the downward gravity caused by the elevator car's own weight and the load inside the car, and the upward pull on the elevator car caused by the lower end of the flexible connector. Therefore, the motion equation of the elevator car should be:

[0078]

[0079] in:

[0080] m 厢 Used to represent the total mass of the elevator car and the load in the car;

[0081] m 链 Used to indicate the quality of the compensation chain;

[0082] g is the gravity coefficient;

[0083] F2 is used to represent the downward pulling force generated by the upper end of the elevator car on the flexible connector, which is the first force mentioned above.

[0084] v2 is used to represent the speed detection value of the elevator car, so it is used The acceleration of the elevator car can be calculated.

[0085] The weight of the elevator car and the weight of the load in the car m 厢 The mass m of the compensation chain can be obtained by measuring the weighing device installed on the car. 链 is a fixed value. Therefore, as long as the real-time speed of the elevator car is obtained, the value of the first force between the elevator car and the flexible connector can be calculated. In the embodiment of the present invention, the real-time speed of the elevator car can be detected by detecting the absolute position of the elevator car, that is, the speed detection value of the elevator car mentioned above.

[0086] Accordingly, in the above-mentioned car speed controller 25, the difference between the externally input given speed instruction of the elevator car and the speed detection value of the elevator car is input into the above-mentioned formula (1), and the final output is the instruction value of the first force, that is, how to adjust so that the actual operation of the elevator car matches the given speed instruction as much as possible. In the present invention, F is used 2_ref Indicates the command value of the first force.

[0087] The above detection of the elevator car's own weight and the weight of the load in the car m 厢 The method of obtaining the speed detection value of the elevator car by the above-mentioned detection can be implemented by using the existing technology, and will not be described in detail here.

[0088] In a preferred embodiment of the present invention, the first force generating module further comprises:

[0089] Spring force calculation submodule 27: calculates the spring force of the flexible connector according to the elongation deformation of the flexible connector;

[0090] Resistance calculation submodule 28: calculates the resistance of the flexible connector according to the speed of the flexible connector's elongation and deformation;

[0091] The difference calculation submodule is used to output the difference between the spring force and the resistance as the first action force.

[0092] Furthermore, as mentioned above, during the operation of the elevator equipment, the flexible connector between the elevator car and the drive wheel can be equivalent to a combination of a spring and a damper when subjected to the tension of the elevator car and the drive wheel. The spring effect is manifested in that when it is subjected to an external force along its length, it will produce an elongation deformation in the same direction as the external force, and the amount of this elongation deformation is related to the external tension; the damping effect is manifested in that when the flexible connector is deformed, it will produce resistance that hinders its deformation, and the magnitude of this resistance is related to the speed at which the elongation deformation is generated. Therefore, when considering the force analysis of the flexible connector, the spring deformation effect and the damping effect of the flexible connector should be comprehensively considered.

[0093] In addition, the flexible connector is affected by its own gravity due to its own mass, and the effect of gravity on different parts of the flexible connector is different. Specifically, the closer a point on the flexible connector is to the drive wheel, the greater the gravity acting on that point, and the greater the elongation deformation at that point, due to the relatively longer length of the flexible connector below it, and vice versa. Therefore, when analyzing the elongation deformation of the flexible connector, it cannot be simply viewed as a lumped parameter system, but rather as a distributed parameter system. The elongation deformation of each point on the flexible connector will change and is closely related to the external force affecting that point.

[0094] In the present invention, for the spring effect of the flexible connector, the microelement method is used to analyze the elongation deformation of the flexible connector. For a microelement dx on the flexible connector, the elongation deformation dL generated by it should be expressed as:

[0095]

[0096] in,

[0097] F is used to represent the external force on the microelement dx of the flexible connector;

[0098] E is used to represent the elastic modulus of the flexible connector;

[0099] dx is used to represent the length of the infinitesimal element.

[0100] Then Figure 1 As shown in , the elongation deformation caused by the flexible connection between the driving wheel and the micro-element dx should be the sum of the elongation deformations of all micro-elements dx. Therefore, the relationship between the elongation deformation caused by the flexible connection between the driving wheel and a micro-element dx and the position x of the micro-element dx can be expressed as:

[0101]

[0102] in,

[0103] ΔL(x) is used to represent the elongation from the driving wheel to position x;

[0104] F 弹 That is, the external force on the microelement dx of the flexible connector mentioned above, when the deformation speed of the microelement is not considered, the external force F can be considered as a spring force, so F is used here. 弹 express.

[0105] According to the above formula (3), if the elongation deformation of the flexible connector is known, the spring force F on the flexible connector can be directly calculated. 弹, that is, the spring effect of the flexible connector can be quantified. The elongation deformation of the flexible connector can be expressed by the difference between the travel distance of the elevator car and the rotation distance of the drive wheel, that is, the edge linear velocity of the drive wheel can be calculated by multiplying the rotation angle θ of the drive wheel by the radius R of the drive wheel, and then the difference between the edge linear velocity and the displacement speed of the elevator car can be calculated to obtain the elongation deformation of the flexible connector. The rotation angle θ of the drive wheel can be obtained by the rotary encoder set inside the drive wheel, and the displacement speed of the elevator car can be obtained by detecting the absolute speed of the elevator car as described above. Therefore, the elongation deformation of the flexible connector can be calculated by real-time detection, that is, the elongation deformation of the flexible connector is known. According to the above formula (3), the spring force F on the flexible connector can be obtained 弹 In other words, the spring force calculation submodule 27 can use the above formula (3) to calculate the spring force F generated on the flexible connector based on the known quantity. 弹 .

[0106] It should be noted that when the elevator equipment is a traction elevator, the difference between the rotation angle of the traction sheave and the displacement speed detection results of the elevator car cannot be directly equivalent to the elongation deformation of the flexible connector. It should also include the slippage generated between the flexible connector and the traction sheave during the movement of the elevator car. This slippage is inevitable during the operation of a traction elevator and cannot be reduced. However, it can be corrected by the known distance between two fixed reference objects in the elevator shaft, such as the doors between two adjacent elevator floors, or other fixed objects. The premise of the correction is that the elevator car has passed the two fixed objects, that is, it has traveled the above-mentioned known distance.

[0107] When the elevator equipment is a non-traction elevator, since the driving wheel control does not produce slip, the elongation deformation of the flexible connector can be directly obtained according to the difference between the rotation angle of the driving wheel and the displacement speed of the elevator car.

[0108] In the embodiment of the present invention, considering that the slip amount has little effect on the overall elongation deformation of the flexible connector, in order to unify the calculation methods of traction elevators and non-traction elevators, the influence of the slip amount is not considered here, and ΔL is directly used to represent the elongation deformation of the flexible connector. This ΔL is the sum of the elongations ΔL(x) corresponding to the infinitesimal element dx at each position on the flexible connector.

[0109] In the present invention, regarding the damping effect of the flexible connector, as described above, the damping force is related to the elongation deformation of the flexible connector. Therefore, the damping force of the flexible connector can be expressed by the following formula:

[0110]

[0111] in,

[0112] F 阻 Used to represent the damping force of the flexible connection;

[0113] c is the damping coefficient of the flexible connector.

[0114] The elongation deformation of the flexible connector can be obtained according to the above detection values, and the resistance of the flexible connector can be obtained according to formula (4), that is, the damping effect of the flexible connector can be quantified.

[0115] Furthermore, for a specific microelement at the connection between the flexible connector and the elevator car, the tension exerted by the elevator car, the load in the car, and the compensation chain is equal to the difference between the spring force and the damping force exerted on the specific microelement by the adjacent microelement, which can be expressed as:

[0116] F2=F 弹 -F 阻 ; (5)

[0117] Then the spring force F of the flexible connector is calculated in the spring force calculation submodule 26 and the resistance calculation submodule 27 respectively. 弹 and resistance F 阻 After that, the difference calculation submodule can calculate the first force F2 according to the above formula (5).

[0118] In a preferred embodiment of the present invention, the drive control system further comprises:

[0119] Compensation torque generating unit 29: generates compensation torque according to the speed detection value of the driving motor, the speed detection value of the elevator car and the mass of the flexible connection body;

[0120] The compensation unit 30 compensates the desired torque of the drive motor using at least the compensation torque output by the compensation torque generation unit to obtain a final drive motor torque instruction, which is the final instruction value acting on the drive motor of the elevator device and driving and controlling the elevator device.

[0121] Furthermore, for a non-traction elevator, the compensation unit 30 uses the sum of the compensation torque output by the compensation torque generation unit 29 and the desired torque of the drive motor as the final drive motor torque instruction.

[0122] For traction elevators, the influence of the torque generated by the counterweight device needs to be considered. Therefore, the compensation unit 30 first calculates the sum of the compensation torque output by the compensation torque generation unit 29 and the desired torque of the drive motor and uses it as a preliminary result. Then, the difference between the preliminary result and the torque generated by the counterweight device is calculated and the difference is used as the final drive motor torque command. Specifically, the force analysis of the flexible connector itself is performed:

[0123] For the flexible connector, there are mainly the downward pulling force F2 exerted by all the components under the elevator car (including the elevator car, partial load and compensation chain) on the lower end of the flexible connector, the upward pulling force F1 exerted by the driving wheel on the upper end of the flexible connector, and the self-weight force F of the flexible connector. 绳 , then the motion equation of the flexible connector should be:

[0124] F2+F 绳 -F1=m 绳 ·a 绳 ; (6)

[0125] in,

[0126] m 绳 Used to represent the mass of the flexible connector;

[0127] a 绳 Used to represent the equivalent acceleration of a flexible connection body.

[0128] In the above formula (6):

[0129] F 绳 It is only related to the flexible connector itself and is calculated according to the following formula:

[0130] F 绳 =ρgl; (7)

[0131] ρ is the linear density of the flexible connector;

[0132] l is the length of the flexible connector.

[0133] Equivalent acceleration a of the flexible connector 绳 can be expressed as:

[0134] a 绳 =a1+a2; (8)

[0135] a1 is used to represent the acceleration of the flexible connector, which can be calculated based on the angular acceleration of the driving wheel, that is, the angular acceleration of the driving wheel is multiplied by the radius R of the driving wheel, which will not be repeated here.

[0136] Regarding the above formula (7), although the flexible connector will stretch after being subjected to tension and its linear density ρ will also decrease accordingly, this change is very subtle and has little impact on the overall system. Therefore, the change in linear density ρ is ignored in the present invention and is treated as a constant value.

[0137] The reason why the acceleration of the flexible connector is not directly used to represent its equivalent acceleration is as mentioned above. During the actual operation of the elevator car, the forces acting on different positions of the flexible connector are different. This is mainly because the gravity at different positions on the flexible connector will change according to the change in the length of the flexible connector below that position and the change in the length of the compensation chain. Therefore, it will affect the deformation speed and deformation acceleration of the flexible connector at different positions. After considering the above factors, the concept of deformation equivalent acceleration a2 of the flexible connector is introduced. The final equivalent acceleration a can be obtained only after the deformation equivalent acceleration a2 is used to correct the acceleration a1 of the flexible connector calculated from the angular acceleration of the drive wheel. 绳 The deformation equivalent acceleration a2 can be calculated by the elongation deformation variable ΔL(x) on each microelement dx, that is, the deformation equivalent acceleration a2 can be obtained by differentiating the elongation deformation variable ΔL with respect to time.

[0138] In addition, in engineering practice, the deformation length of the flexible connector is generally small relative to its length in its natural state, and the acceleration caused by the dynamic characteristics of the flexible connector is not particularly obvious in its length direction. Therefore, for some application scenarios where the accuracy requirements for acceleration are not so high (for example, the speed controller itself has a certain robustness), the acceleration a1 of the flexible connector can be directly used as its equivalent acceleration a 绳 , without having to calculate the equivalent acceleration a using the above formula (8).

[0139] Therefore, after the command value of the first force F2 and F 绳 、m 绳 And the equivalent acceleration a of the flexible connector 绳 After that, the above formula (6) can be used to calculate the command value of the upward pulling force F1 applied by the driving wheel to the upper end of the flexible connector.

[0140] Then the force analysis of the driving wheel shows that:

[0141] For a traction elevator, the driving wheel is the traction wheel, which is mainly affected by the torque T applied by the driving motor. e , the torque T generated by the tension applied to the traction sheave by the upper end of the flexible connector on the elevator car side 绳 (that is, compensation torque) and the torque T generated by the tension applied by the flexible connector on the traction sheave on the counterweight device side 重 Since the dynamic characteristics of the flexible connection between the counterweight device and the traction sheave have relatively little effect on the speed control on the elevator car side, the connection between the counterweight device and the traction sheave is regarded as a rigid connection in this application.

[0142] The anticlockwise rotation direction of the traction wheel is the positive direction, and the clockwise rotation direction is the negative direction. The motion equation of the traction wheel can be expressed as:

[0143]

[0144] Where J is used to represent the equivalent moment of inertia of all components suspended on the traction sheave (including the flexible connector, counterweight, elevator car, and compensation chain);

[0145] ω is the rotor angular velocity of the elevator equipment's drive motor.

[0146] Transforming the above formula (9) we can get:

[0147]

[0148] In the above formula (10), F1 can be calculated by the above formula (6) to obtain the corresponding instruction value.

[0149] R is the radius of the traction sheave.

[0150] In the present invention, after the rotor torque T of the driving motor is known, e , the command value of the pulling force F1, the radius R of the traction wheel, and the mass m of the elevator car and the load in the car 重 Then, the command value v of the edge linear velocity v1 of the traction wheel can be calculated according to the above formula (10): 1_ref It should be noted that the car speed controller 25 outputs the first force command value F 2_ref , which is used to represent the difference between the actual first force and the first force expected by the given car speed command. The edge linear velocity command value v of the traction wheel output here is 1_ref , which is used to indicate the expected value after adjusting and compensating the real-time edge linear velocity.

[0151] For non-traction elevators, since they are driven by driving wheels and have no counterweight device, T does not exist in the above formula (9). 重 , there is no influence of the counterweight device in the equivalent moment of inertia J, and m does not exist in the above formula (10) 重 ·g·R, the rest of the calculation method is the same as that of the traction elevator and will not be repeated here.

[0152] Furthermore, when the driving wheel is a traction wheel, it is necessary to consider the torque T generated by the counterweight device. 重 The effect of the desired torque output by the motor current controller and the above compensation torque T 绳 After adding, calculate the added result and torque T 重The difference between them is used as the final drive motor torque instruction to drive and control the elevator equipment using a double closed-loop variable voltage and variable frequency speed regulation method.

[0153] When the driving wheel is a non-traction wheel, that is, a self-driving wheel, it is only necessary to convert the desired torque output by the driving motor current controller and the above-mentioned compensation torque T 绳 The sum of the two can be used as the final drive motor torque command, without considering the impact of the counterweight device, that is, there is no need to calculate the torque T 重 .

[0154] In a preferred embodiment of the present invention, the compensation torque generating unit 29 further comprises:

[0155] A first force generating module: generating a first force between the flexible connector and the elevator car according to a speed detection value of the drive motor and a speed detection value of the elevator car;

[0156] The first calculation module calculates the gravity acting on the flexible connector according to the position of the elevator car and the linear density of the flexible connector;

[0157] The second calculation module calculates the sum of the gravity of the flexible connector and the first force as a first intermediate result, then calculates the product of the mass of the flexible connector and the equivalent acceleration of the flexible connector as a second intermediate result, and finally calculates and outputs the difference between the first intermediate result and the second intermediate result;

[0158] The third calculation module calculates the product of the output result of the second calculation module and the radius of the driving wheel and uses it as the compensation torque.

[0159] Specifically:

[0160] The operating principle of the first force generating module has been explained above and will not be repeated here.

[0161] The first calculation module calculates the gravity F of the flexible connector according to the above formula (7): 绳 .

[0162] The second calculation module calculates the pulling force F1 according to the above formula (6).

[0163] The third calculation module uses the formula T 绳 =F1·R is realized, and the compensation torque is finally obtained.

[0164] In a preferred embodiment of the present invention, the control object of the flexible connector deformation controller is the flexible connector located between the drive wheel and the elevator car. The mathematical model of the flexible connector is constructed according to the above formulas (3)-(5). Therefore, the above flexible connector deformation controller 26 uses the flexible connector as the controlled object and finally calculates the command value v of the edge linear velocity of the drive wheel according to the above formulas (6)-(8) and (10). 1_ref .

[0165] In a preferred embodiment of the present invention, the difference between the acceleration of the elevator car at the current moment and the linear acceleration of the driving wheel is used as the equivalent acceleration of the flexible connector at the next moment.

[0166] Specifically, theoretically, the equivalent acceleration a of the flexible connector can be calculated using the above formula (8) and related descriptions: 绳 But as mentioned above, the calculation of a 绳 It is necessary to first calculate the acceleration a1 of the flexible connector and the deformation acceleration a2 of the flexible connector. The calculation of the deformation acceleration a2 requires the calculation of the overall elongation deformation ΔL of the flexible connector, so it is necessary to calculate the elongation deformation ΔL(x) of each infinitesimal element dx on the flexible connector. Considering the high computational complexity of this entire calculation process, in practice, in order to balance accuracy and processing efficiency, in this embodiment, the difference between the acceleration of the elevator car at the current moment and the linear acceleration of the drive wheel is directly used as the equivalent acceleration of the flexible connector at the next moment. The acceleration of the above-mentioned elevator car can be obtained by detecting the absolute position of the elevator car, and the linear acceleration of the drive wheel can be obtained by the angular acceleration of the drive wheel and the radius of the drive wheel. The angular acceleration of the drive wheel can be detected by the encoder inside the drive wheel. These detection and calculation processes are the same as those above and will not be repeated here.

[0167] Of course, if the accuracy of the calculated values ​​is considered purely without considering the processing efficiency and the computing power of the system, the equivalent acceleration of the flexible connector can be calculated according to the above formula (8) and its related descriptions according to the theoretical design. That is, the following formula can be integrated to calculate the equivalent acceleration of the flexible connector:

[0168]

[0169] Here, ω is used to represent the angular velocity of the driving wheel.

[0170] To sum up, in the technical solution of the present invention, after performing a force analysis on the elevator car, driving wheel and flexible connector in the elevator equipment, speed controllers for the elevator car and the flexible connector are added to the traditional voltage / current dual closed-loop variable-frequency speed regulation control system, and the compensating torque of the driving wheel affected by the flexible connector and the torque generated by the counterweight device are added, thereby solving the problem of vertical vibration of the elevator car from the root, which can not only ensure the passengers' riding experience, but also improve the speed control performance of the elevator car and improve the control efficiency.

[0171] The above description is only a preferred embodiment of the present invention and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. An elevator drive control system, applied to an elevator device, the elevator device comprising an elevator car, a counterweight device, a drive wheel, and a flexible connector connecting the elevator car and the counterweight device and suspended from the drive wheel, the drive control system comprising: A drive motor speed detector for detecting the speed of the drive motor of the elevator device, a drive motor current detector for detecting the current of the drive motor, a drive motor current controller for generating a desired torque of the drive motor according to a difference between a current command value of the drive motor and a current detection value, and a drive motor speed controller for generating the current command value of the drive motor according to a difference between a speed command value of the drive motor and a speed detection value; characterized in that the drive control system further includes: A drive motor speed command generating unit generates a speed command value of the drive motor according to an externally input car speed command, a rotation detection value of the drive motor, and a speed detection value of the elevator car; The drive control system further includes: A compensation torque generating unit is configured to generate a compensation torque according to a speed detection value of the drive motor, a speed detection value of the elevator car, and a mass of the flexible connector; a compensation unit: compensating the desired torque of the drive motor by at least using the compensation torque output by the compensation torque generation unit to obtain a final drive motor torque command; The compensation unit uses the sum of the compensation torque output by the compensation torque generation unit and the desired torque of the drive motor as the final drive motor torque command; or The compensation unit first calculates the sum of the compensation torque output by the compensation torque generation unit and the desired torque of the drive motor as a preliminary result, then calculates the difference between the preliminary result and the torque generated by the counterweight device, and uses the obtained difference as the final drive motor torque instruction.

2. The elevator drive control system according to claim 1, wherein: The compensation torque generating unit further comprises: A first force generating module is configured to generate a first force between the flexible connector and the elevator car according to a speed detection value of the drive motor and a speed detection value of the elevator car; A first calculation module is configured to calculate the gravity exerted on the flexible connector according to the position of the elevator car and the linear density of the flexible connector; A second calculation module is configured to calculate the sum of the gravity of the flexible connector and the first force as a first intermediate result, then calculate the product of the mass of the flexible connector and the equivalent acceleration of the flexible connector as a second intermediate result, and finally calculate and output the difference between the first intermediate result and the second intermediate result; A third calculation module is configured to calculate the product of the output result of the second calculation module and the radius of the driving wheel and use the product as the compensation torque.

3. The elevator drive control system according to claim 2, wherein: The first force generation module further comprises: Spring force calculation submodule: calculates the spring force of the flexible connector according to the elongation deformation of the flexible connector; Resistance calculation submodule: calculates the resistance of the flexible connector according to the speed of the flexible connector's elongation and deformation; The difference calculation submodule is used to output the difference between the spring force and the resistance as the first action force.

4. The elevator drive control system according to claim 3, wherein: The spring force calculation submodule calculates the spring force of the flexible connector according to the following formula: ； in, The sum of the elongation deformations of the flexible connection body between the driving wheel and the position x of the microelement dx on the flexible connection body is used to represent the sum of the elongation deformations of the flexible connection body between the driving wheel and the microelement dx on the flexible connection body; Used to represent the spring force exerted on the microelement dx on the flexible connector; E is used to represent the elastic modulus of the flexible connector; It is calculated by the difference between the rotation detection value of the drive motor and the speed detection value of the elevator car.

5. The elevator drive control system according to claim 3, wherein: The resistance calculation submodule calculates the resistance of the flexible connector according to the following formula: ； in, Used to represent the resistance of the flexible connector; Used to represent the sum of the elongation deformation of the flexible connector; c represents the damping coefficient of the flexible connector.

6. The elevator drive control system according to claim 2, wherein: The difference between the acceleration of the elevator car at the current moment and the linear acceleration of the driving wheel is used as the equivalent acceleration of the flexible connection at the next moment.

Images