A traction machine brake coil impedance adaptive control method

Abstract

The application discloses a kind of traction machine brake-in coil impedance adaptive control method, comprising S1: preset brake-in coil power-on rate threshold and temperature;S2: monitor brake-in coil power-on rate and monitor brake-in coil temperature;S3: when brake-in coil power-on rate is less than or equal to preset power-on rate threshold, brake-in coil temperature is lower than or higher than preset temperature, the resistance and inductance of brake-in coil are re-learned;S4: staff starts control system and enters brake-in coil parameter self-learning mode, and the resistance and inductance of brake-in coil are learned;S5: according to the result after brake-in coil self-learning, current closed-loop control parameter is recalculated.The scheme is by starting control system and entering brake-in coil parameter self-learning mode, and the resistance and inductance of brake-in coil are learned, thereby obtaining better current control effect, reducing the overshoot of brake-in current in the strong excitation stage, and the current fluctuation in maintenance stage, to reduce the noise when brake-in operates.

Description

Technical Field

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

[0002] In order to reduce noise, the existing elevator control system brake generally adopts current source chopping control, as shown in the attached manual. Figure 1 As shown in the figure, the brake current closed loop of this solution 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. Existing solutions 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 the brake is opened, and the current fluctuation in steady state will also become larger, resulting in noise and other problems.

[0003] Chinese invention patent CN 107840219 B discloses a brake coil control circuit, comprising 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 to the main power supply for the brake coil. The solution also provides a brake coil control method, a brake control power supply device incorporating the brake coil control circuit, and an elevator utilizing the brake control power supply device. This solution utilizes the brake coil control circuit to control the brake coil's shutdown, which reduces 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 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, which achieves better current control effect by self-learning the brake coil parameters, reduces 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 brake operation.

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

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

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

[0009] S2: monitors the energization rate of the brake coil and the temperature of the brake coil;

[0010] S3: When the brake coil's energization rate is less than or equal to the preset energization rate threshold, and the brake coil's temperature is lower than or higher than the preset temperature, the brake coil's resistance and inductance 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 based on 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 operation instruction is received, the control system operation 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 moment, “k-1” represents the k-1th sampling moment, 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 ” represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment respectively.

[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 across the brake coil is calculated using 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 based on 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 energization rate of the brake coil and the temperature of the brake coil. When the energization rate of the brake coil is less than or equal to a preset energization 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. 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 This is a current source chopping control circuit diagram of an embodiment of a method for adaptively controlling the impedance of a traction machine brake coil according to the present invention;

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

[0026] Figure 3 A circuit diagram of identifying the brake coil inductance through 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 diagram showing the steps for calculating the RMS current of an embodiment of a method for adaptively controlling the 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. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the present invention, the technical solutions of the present invention are further described below in conjunction with the accompanying drawings and embodiments. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the 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 those of ordinary skill in the art without making creative efforts 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 various 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 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 such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the ability of ordinary technicians in this field to implement them. 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 here 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 brake coil's energization rate threshold and temperature;

[0034] S2: monitors the energization rate of the brake coil and the temperature of the brake coil;

[0035] S3: When the brake coil's energization rate is less than or equal to the preset energization rate threshold, and the brake coil's temperature is lower than or higher than the preset temperature, the brake coil's resistance and inductance 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 based on the results of the brake coil self-learning.

[0038] In practical applications 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 moment, “k-1” represents the k-1th sampling moment, 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 ” represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment respectively.

[0042] Identify the brake coil resistance R by volt-ampere method s : That is, by injecting low-voltage DC into the brake coil, 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, 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 is considered invalid, it can be simplified to Figure 3 As shown in the circuit diagram; In the actual application of this embodiment, the S4 is used to identify the brake coil inductance L through a high-frequency pulse test s , the high-frequency voltage U across the brake coil is calculated using 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 the differentiation of a function. In mathematics, the most common differential operator is d / dx, which represents the derivative of the independent variable x.

[0047] In practical applications of this embodiment, the parameters of the current closed-loop control are adjusted based on the calculation results of the resistance formula and the inductance formula of the brake coil.

[0048] As the instruction manual Figure 4 As shown, capacitive current refers to the current flowing through a capacitor. According to Ohm's law, the magnitude of the capacitive current is related to the voltage across the capacitor. When the voltage across the capacitor changes periodically, the capacitive current also changes periodically, and this change can be described by a sinusoidal function. The root mean square (RMS) of the capacitive current is the square root of the average square value of the capacitive current over a period of time and is an important indicator of the capacitive current. Figure 4To calculate the RMS current, first set a 1-second cycle, calculate the RMS current every 1 second, record 30 RMS values, and then calculate the RMS current within 30 seconds (MotoOH_30s) based on the 30 recorded RMS values. Then follow the previous steps to calculate the next MotoOH_30s, record the most recent 30 MotoOH_30s, and then average MotoOH_1min, MotoOH_2min, and MotoOH_15min. Then record the most recent 8 MotoOH_15s, and finally average MotoOH_2hour.

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

[0050] This solution calculates the brake coil's energization rate over a period of time based on the frequency of elevator operation. When the set threshold, DutyH, is reached, the brake coil temperature is considered to have exceeded the set temperature and the coil parameters have changed significantly. The brake coil's resistance and inductance need to be relearned, and the brake coil self-learning request is enabled.

[0051] If the elevator's operating frequency decreases or the elevator stops for a long time, and the brake coil's energization rate falls below the set threshold, DutyL, the brake coil temperature is considered below the set temperature and the coil parameters have changed significantly, requiring relearning of the brake coil's resistance and inductance. The brake coil self-learning request is then enabled. When the elevator stops, the control system enters brake coil parameter self-learning mode, automatically learning the resistance and inductance and recalculating the appropriate current closed-loop control parameters based on the learning results. Furthermore, if a system run command is received during the learning process, the brake self-learning mode automatically exits and responds to the system run command.

[0052] To sum up, 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 brake operation.

[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 skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to 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 brake coil's energization rate threshold and temperature; S2: monitors the energization rate of the brake coil and the temperature of the brake coil; S3: When the brake coil's energization rate is less than or equal to the preset energization rate threshold, and the brake coil's temperature is lower than or higher than the preset temperature, the brake coil's resistance and inductance 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 based on 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, wherein: The self-learning method of the brake coil resistance in S4 is to identify the brake coil resistance R by volt-ampere method. s Calculate the brake coil resistance R using the following resistance formula: s : 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 ” represent the brake coil current at the kth sampling moment and the brake coil current at the k-1th sampling moment respectively.

4. The method for adaptively controlling the impedance of a traction machine brake coil according to claim 3, characterized in that: When a high-frequency voltage U is applied to both ends of the brake coil through the drive module s In S4, the brake coil inductance L is identified by a high-frequency pulse test. s , the high-frequency voltage U across the brake coil is calculated using the following inductance formula: s : Among them, "i s ” represents the inductor current, and "d" or "dt" represents the differential operator.

5. The method for adaptively controlling the impedance of a traction machine brake coil according to claim 4, characterized in that: The parameters of the 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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