Tractor band-type brake coil impedance self-adaptive control method

Abstract

The invention discloses a traction machine band-type brake coil impedance self-adaptive control method. The method comprises the steps that S1, the power-on rate threshold value and the temperature of a band-type brake coil are preset; s2, monitoring the power-on rate of the band-type brake coil and monitoring the temperature of the band-type brake coil; s3, when the power-on rate of the band-type brake coil is smaller than or equal to a preset power-on rate threshold value and the temperature of the band-type brake coil is lower than or higher than a preset temperature, the resistance and inductance of the band-type brake coil are learned again; s4, a worker starts a control system and enters a band-type brake coil parameter self-learning mode, and the resistance and inductance of the band-type brake coil are learned; and S5, recalculating the current closed-loop control parameters according to the self-learning result of the band-type brake coil. According to the scheme, by starting the control system and entering the band-type brake coil parameter self-learning mode, the resistance and inductance of the band-type brake coil are learned, so that a better current control effect is obtained, overshoot of band-type brake current in a strong excitation stage and current fluctuation in a maintenance stage are reduced, and noise during band-type brake operation is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of elevator control systems, and in particular relates to an impedance adaptive control method for a traction machine brake coil. Background Art

[0002] In order to reduce noise, the elevator control system of the prior art generally adopts current source chopping control, as shown in the attached manual. Figure 1 As shown; the brake current closed loop of this scheme adopts PI regulator for control. In order to achieve better control effect and reduce the noise caused by brake current overshoot, it is necessary to select appropriate proportional integral parameters. The existing schemes generally adopt fixed proportional integral parameters, which will not be adjusted during the subsequent operation of the elevator. In this way, when the elevator runs frequently and the temperature of the brake coil rises, it will cause a large current overshoot when opening the gate, and the current fluctuation will also increase in steady state, resulting in noise and other problems.

[0003] Chinese invention patent CN 107840219 B discloses a brake coil control circuit, including a control unit, an auxiliary power supply, a first switch, an output detection unit and a signal coupling unit. The control unit is connected to the auxiliary power supply, the first switch, the output detection unit and the signal coupling unit respectively. The first switch connects the auxiliary power supply and the main power supply for the brake coil. The scheme also provides a brake coil control method, a brake control power supply device with the brake coil control circuit built in, and an elevator using the brake control power supply device; this scheme realizes the shutdown control of the brake coil through the brake coil control circuit, which reduces the noise to a certain extent, but the effect in actual application may not be ideal.

[0004] Therefore, the present invention provides a method for adaptively controlling the impedance of a traction machine brake coil to solve the technical problems raised by the above-mentioned background technology. Summary of the invention

[0005] In response to the problems raised by the above background technology, the purpose of the present invention is to provide a method for adaptively controlling the impedance of a traction machine brake coil, thereby obtaining a better current control effect through self-learning of the brake coil parameters, reducing the overshoot of the brake current in the strong excitation stage and the current fluctuation in the maintenance stage, thereby reducing the noise during the operation of the brake.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for adaptively controlling the impedance of a traction machine brake coil comprises the following steps:

[0008] S1: preset the energization rate threshold and temperature of the brake coil;

[0009] S2: monitor the power-on rate of the brake coil and the temperature of the brake coil;

[0010] S3: When the power-on rate of the brake coil is less than or equal to the preset power-on rate threshold and the temperature of the brake coil is lower than or higher than the preset temperature, the resistance and inductance of the brake coil are relearned;

[0011] S4: The staff starts the control system and enters the brake coil parameter self-learning mode to learn the resistance and inductance of the brake coil;

[0012] S5: Recalculate the current closed-loop control parameters according to the results of the brake coil self-learning.

[0013] It is further defined that when the brake coil parameters are self-learned and the control system operating instruction is received, the control system operating instruction is responded to first.

[0014] It is further defined that the self-learning method of the brake coil resistance in S3 is to identify the brake coil resistance R by volt-ampere method. s , calculate the brake coil resistance R by the following formula s :

[0015]

[0016] Among them, "k" represents the kth sampling time, "k-1" represents the k-1th sampling time, and "U k ” and “U k-1 " respectively represent the brake coil voltage at the kth sampling moment and the brake coil voltage at the k-1th sampling moment, "I k ” and “I k-1 " respectively represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment.

[0017] It is further defined that the identification of the brake coil inductance L by the high-frequency pulse test in S4 s , the high-frequency voltage U at both ends of the brake coil is calculated by the following formula s :

[0018]

[0019] Among them, "i s ” represents the inductor current, and “d” or “dt” represents the differential operator.

[0020] It is further defined that the parameters of the current closed-loop control are adjusted according to the calculation results of the resistance formula and the inductance formula of the brake coil.

[0021] Beneficial effects of the present invention:

[0022] The present invention provides an adaptive control method for the impedance of a traction machine brake coil, which monitors the power-on rate of the brake coil and the temperature of the brake coil. When the power-on rate of the brake coil is less than or equal to a preset power-on rate threshold and the temperature of the brake coil is lower than or higher than a preset temperature, the staff starts the control system and enters the brake coil parameter self-learning mode to learn the resistance and inductance of the brake coil. Finally, the current closed-loop control parameters are recalculated according to the results of the brake coil self-learning, and the proportion and integral parameters of the current closed-loop control are adjusted according to the resistance and inductance, thereby obtaining a better current control effect, reducing the overshoot of the brake current in the strong excitation stage and the current fluctuation in the maintenance stage, thereby reducing the noise during the operation of the brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention can be further illustrated by the non-limiting examples given in the accompanying drawings;

[0024] Figure 1 A current source chopping control circuit diagram of an embodiment of a method for adaptively controlling impedance of a traction machine brake coil according to the present invention;

[0025] Figure 2 A circuit diagram of identifying the resistance of a brake coil using a volt-ampere method according to an embodiment of a method for adaptively controlling the impedance of a traction machine brake coil of the present invention;

[0026] Figure 3 A circuit diagram of identifying the inductance of a brake coil by a high-frequency pulse test in an embodiment of a method for adaptively controlling the impedance of a traction machine brake coil according to the present invention;

[0027] Figure 4 A current root mean square calculation step diagram of an embodiment of a method for adaptively controlling impedance of a traction machine brake coil according to the present invention;

[0028] Figure 5 The present invention is a flowchart of the steps of an embodiment of a method for adaptively controlling the impedance of a traction machine brake coil according to the present invention. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. 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 the field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0031] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] As the instruction manual Figure 1 As shown, a method for adaptively controlling the impedance of a traction machine brake coil of the present invention comprises the following steps:

[0033] S1: preset the energization rate threshold and temperature of the brake coil;

[0034] S2: monitor the power-on rate of the brake coil and the temperature of the brake coil;

[0035] S3: When the power-on rate of the brake coil is less than or equal to the preset power-on rate threshold and the temperature of the brake coil is lower than or higher than the preset temperature, the resistance and inductance of the brake coil are relearned;

[0036] S4: The staff starts the control system and enters the brake coil parameter self-learning mode to learn the resistance and inductance of the brake coil;

[0037] S5: Recalculate the current closed-loop control parameters according to the results of the brake coil self-learning.

[0038] In the actual application of this embodiment, when the brake coil parameters are self-learned and the control system operation instruction is received, the control system operation instruction is responded to first.

[0039] As the instruction manual Figure 2 As shown, in the actual application of this embodiment, the self-learning method of the brake coil resistance in S3 is to identify the brake coil resistance R by volt-ampere method. s , calculate the brake coil resistance R by the following formula s :

[0040]

[0041] Among them, "k" represents the kth sampling time, "k-1" represents the k-1th sampling time, and "U k ” and “U k-1 " respectively represent the brake coil voltage at the kth sampling moment and the brake coil voltage at the k-1th sampling moment, "I k ” and “I k-1 " respectively represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment.

[0042] Identification of brake coil resistance R by volt-ampere method s : That is, by injecting low-voltage DC into the brake coil, and then chopping the bus voltage to obtain a high-frequency voltage pulse sequence, and finally keeping the duty cycle constant to obtain an equivalent low-voltage DC current.

[0043] As the instruction manual Figure 3 As shown in the figure, when a high-frequency voltage U is applied to both ends of the brake coil through the drive module s When the internal resistance of the brake coil can be considered invalid, it can be simplified as Figure 3 As shown in the circuit diagram; In the practical application of this embodiment, the brake coil inductance L is identified by the high-frequency pulse test in S4 s , the high-frequency voltage U at both ends of the brake coil is calculated by the following formula s :

[0044]

[0045] Among them, "i s ” represents the inductor current, and “d” or “dt” represents the differential operator.

[0046] A differential operator is a symbol that represents a differential operation on a function. In mathematics, the most common differential operator is d / dx, which represents the derivative operation with respect to the independent variable x.

[0047] In the actual application of this embodiment, the parameters of the current closed-loop control are adjusted according to the calculation results of the resistance formula and the inductance formula of the brake coil.

[0048] As the instruction manual Figure 4 As shown, the capacitive current refers to the current passing through the capacitor. According to Ohm's law, the size of the capacitive current is related to the voltage across the capacitor. When the size of the voltage across the capacitor changes periodically, the capacitive current will also change periodically, and this change can be described by a sine function. The root mean square of the capacitive current is the square root of the average value of the square value of the capacitive current in a cycle, and it is an important indicator to describe the size of the capacitive current. Figure 4For the calculation steps of the root mean square current, first set a cycle period of 1 second, calculate the effective value of the current every 1 second, record 30 effective values, and then calculate the root mean square current MotoOH_30s within 30 seconds based on the recorded 30 effective values; then calculate the next MotoOH_30s according to the above steps, record the most recent 30 MotoOH_30s, and then calculate the average of MotoOH_1min, MotoOH_2min and MotoOH_15min, and then record the most recent 8 MotoOH_15s, and finally calculate the average of MotoOH_2hour.

[0049] The principles of this solution are as follows:

[0050] This solution calculates the power-on rate of the brake coil over a period of time according to the frequency of elevator operation. When the set threshold DutyH is reached, it is considered that the brake coil temperature exceeds the set temperature and the coil parameters have changed significantly. It is necessary to relearn the resistance and inductance of the brake coil and set the brake coil self-learning request to be valid.

[0051] If the frequency of elevator operation decreases or the elevator stops for a long time, and the power-on rate of the brake coil is less than the set threshold DutyL, it is considered that the brake coil temperature is lower than the set temperature, and the coil parameters have changed significantly. It is necessary to relearn the resistance and inductance of the brake coil, and set the brake coil self-learning request to be valid. When the elevator stops running, the control system is started to enter the brake coil parameter self-learning mode, automatically learn the resistance and inductance, and recalculate the appropriate current closed-loop control parameters based on the learning results. In addition, if a system operation command is received during the learning process, the brake self-learning mode automatically exits and responds to the system operation command.

[0052] In summary, the present invention provides a method for adaptively controlling the impedance of a traction machine brake coil, which monitors the power-on rate of the brake coil and the temperature of the brake coil. When the power-on rate of the brake coil is less than or equal to a preset power-on rate threshold and the temperature of the brake coil is lower than or higher than a preset temperature, the staff starts the control system and enters the brake coil parameter self-learning mode to learn the resistance and inductance of the brake coil. Finally, the current closed-loop control parameters are recalculated according to the results of the brake coil self-learning, and the proportional and integral parameters of the current closed-loop control are adjusted according to the resistance and inductance, thereby obtaining a better current control effect, reducing the overshoot of the brake current in the strong excitation stage and the current fluctuation in the maintenance stage, thereby reducing the noise during the operation of the brake.

[0053] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for adaptively controlling the impedance of a traction machine brake coil, characterized in that: The steps include: S1: preset the energization rate threshold and temperature of the brake coil; S2: monitor the power-on rate of the brake coil and the temperature of the brake coil; S3: When the power-on rate of the brake coil is less than or equal to the preset power-on rate threshold and the temperature of the brake coil is lower than or higher than the preset temperature, the resistance and inductance of the brake coil are relearned; S4: The staff starts the control system and enters the brake coil parameter self-learning mode to learn the resistance and inductance of the brake coil; S5: Recalculate the current closed-loop control parameters according to the results of the brake coil self-learning.

2. The method for adaptively controlling the impedance of a traction machine brake coil according to claim 1, characterized in that: When the brake coil parameters are self-learned and the control system operation instruction is received, the control system operation instruction is responded to first.

3. The method for adaptively controlling the impedance of a traction machine brake coil according to claim 1, characterized in that: The self-learning method of the brake coil resistance in S3 is to identify the brake coil resistance R by volt-ampere method. s , calculate the brake coil resistance R by the following formula s : Where, "k" represents the kth sampling time, "k-1" represents the k-1th sampling time, and "U k ” and “U k-1 " respectively represent the brake coil voltage at the kth sampling moment and the brake coil voltage at the k-1th sampling moment, "I k ” and “I k-1 " respectively represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment.

4. The method for adaptively controlling the impedance of a traction machine brake coil according to claim 1, characterized in that: The high-frequency pulse test in S4 is used to identify the brake coil inductance L s , the high-frequency voltage U at both ends of the brake coil is calculated by the following formula s : Among them, "i s ” represents the inductor current, and "d" or "dt" represents the differential operator.

5. A method for adaptively controlling the impedance of a traction machine brake coil according to claims 3 and 4, characterized in that: The parameters of current closed-loop control are adjusted based on the calculation results of the resistance formula and inductance formula of the brake coil.

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