Brake power supply control method and device, brake power supply and elevator brake system

Abstract

The invention relates to a band-type brake power supply control method and device, a band-type brake power supply and an elevator band-type brake system.The band-type brake power supply control method comprises the steps that the output voltage of the band-type brake power supply in each preset period is collected to serve as feedback voltage, and the deviation between each feedback voltage and target voltage is calculated; according to the deviation and a PID control parameter, calculating a PID variable quantity of each preset period, and accumulating the previous PID variable quantities to obtain a PID output signal of the current preset period; the PID control parameters comprise a proportional parameter, an integral parameter and a differential parameter; wherein before the band-type brake power supply is connected to a load, the proportion parameter, the integral parameter and the differential parameter are adjusted to be within a first preset range, and then the differential parameter is controlled to be reduced to be within a second preset range; and adjusting the output voltage to the target voltage according to the PID output signal. The output voltage conversion cost of the band-type brake power supply is reduced, and the output voltage precision of the band-type brake power supply is improved.

Description

Technical Field

[0001] The present application relates to the technical field of brake control, and in particular to a brake power supply control method, device, brake power supply and elevator brake system. Background Art

[0002] The brake is a mechanical device usually used in motor systems. Its function is to provide resistance or braking force when the motor stops running to prevent the load from moving unexpectedly or to keep the load in a stable position. The opening and closing of the brake is controlled by the output voltage of the brake power supply. When the brake power supply is connected to the brake, the brake is opened to allow the motor to operate normally; when the brake power supply is disconnected from the brake, the brake stops the motor. The voltage conversion of the traditional pure hardware brake power supply requires a large number of components such as resistors, and the circuit is relatively complex. The voltage required for the brakes of different manufacturers may be different. Therefore, the brake power supply needs to modify the components to change the output voltage to match the brake, resulting in a high control cost for the brake power supply. At the same time, since the voltage conversion of the traditional brake power supply is completed by pure hardware, if there is fluctuation at the input end, there must be fluctuation at the output end, resulting in low voltage accuracy and stability of the brake power supply output, and low control accuracy. Summary of the invention

[0003] Based on this, it is necessary to provide a brake power supply control method, device, brake power supply and elevator brake system to address the above technical problems.

[0004] In a first aspect, an embodiment of the present application provides a brake power supply control method, the method comprising:

[0005] Collecting the output voltage of the brake power supply in each preset cycle as a feedback voltage, and calculating the deviation between each feedback voltage and a target voltage;

[0006] According to the deviation and PID control parameters, the PID change amount of each preset cycle is calculated, and the PID change amounts of all previous cycles are accumulated to obtain the PID output signal of the current preset cycle; the PID control parameters include proportional parameters, integral parameters and differential parameters;

[0007] Wherein, before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to decrease to a second preset range;

[0008] According to the PID output signal, the output voltage is adjusted to be stable before the brake power supply is connected to the load, and is stabilized to the target voltage within the first time after the brake power supply is connected to the load.

[0009] In one embodiment, the brake power supply control method is applied to an elevator brake, the brake power supply is connected to the elevator brake through a brake switch, and before the brake power supply is connected to a load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to decrease to a second preset range, including:

[0010] During the closing process of the brake switch, the proportional parameter, the integral parameter and the differential parameter are adjusted to be within a first preset range, and then the differential parameter is controlled to decrease to be within a second preset range.

[0011] In one embodiment, the adjusting the proportional parameter, the integral parameter and the differential parameter within a first preset range, and then controlling the differential parameter to decrease within a second preset range, includes:

[0012] Adjust the proportional parameter to a range of 0.01 to 0.2, the integral parameter to a range of 0.005 to 0.015, and the differential parameter to a range of 0.1 to 0.5;

[0013] Then the differential parameter is controlled to be reduced to within the range of 0.01 to 0.02.

[0014] In one embodiment, before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and before the differential parameter is controlled to decrease to a second preset range, the method further includes:

[0015] In N preset cycles, the PID output signal is controlled to be a first preset value, and the output current of the brake power supply is collected, and the output voltage adjusted by the first preset value is less than the target voltage;

[0016] When the output current is greater than a current threshold, the input end of the brake power supply is controlled to be disconnected.

[0017] In one embodiment, the method further comprises:

[0018] Collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the product of the output voltage and the output current after the brake switch is closed and before the output current stabilizes as the output capacitance of each preset cycle;

[0019] The ratio of the difference between the output capacitance and the initial capacitance in each preset cycle to the initial capacitance is calculated, and the ratios in multiple preset cycles are compared to determine the aging trend of the output capacitance.

[0020] In one embodiment, the method further comprises:

[0021] Collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the ratio of the output voltage to the output current after the brake switch is closed and the output current is stable as the output resistance of each preset cycle;

[0022] The ratio of the difference between the output resistance and the initial resistance in each preset cycle to the initial resistance is calculated, and the ratios in multiple preset cycles are compared to determine the aging trend of the output resistance.

[0023] In one embodiment, adjusting the proportional parameter, the integral parameter and the differential parameter within a first preset range includes:

[0024] The proportional parameter, the integral parameter and the differential parameter are adjusted in sequence.

[0025] In a second aspect, an embodiment of the present application further provides a brake power supply control device, comprising:

[0026] A data acquisition module is used to collect the output voltage of the brake power supply in each preset cycle and feed it back to the PID control module;

[0027] The PID control module is used to calculate the deviation between each output voltage and the target voltage; and according to the deviation and the PID control parameter, calculate the PID change of each preset cycle, and accumulate the previous PID changes to obtain the PID output signal of the current preset cycle; the PID control parameters include proportional parameters, integral parameters and differential parameters; according to the PID output signal, adjust the output voltage to the target voltage; and before the brake power supply is connected to the load, adjust the proportional parameter, the integral parameter and the differential parameter to a first preset range, and then control the differential parameter to decrease to a second preset range.

[0028] In a third aspect, an embodiment of the present application further provides a brake power supply, which includes a controller and a drive circuit, wherein the drive circuit includes a switch tube, and the controller is used to execute a brake power supply control method as described in any one of the first aspects above, so as to adjust the duty cycle of the switch tube through the PID output signal, thereby adjusting the output voltage of the drive circuit to the target voltage.

[0029] In a fourth aspect, an embodiment of the present application further provides an elevator brake system, comprising a brake power supply, a brake switch and an elevator brake as described in the third aspect above, which are connected in sequence;

[0030] The elevator brake system also includes an elevator control system and a server. The controller and the brake switch are both controlled by the elevator control system. The controller is communicatively connected to the server. The server is used to set the target voltage, and receive and display the output voltage and output current of the brake power supply for each preset cycle.

[0031] The above-mentioned brake power supply control method, device, brake power supply and elevator brake system collect the output voltage of the brake power supply in each preset cycle as the feedback voltage, calculate the deviation between each feedback voltage and the target voltage; calculate the PID change amount of each preset cycle according to the deviation and PID control parameters, and accumulate the previous PID changes to obtain the PID output signal of the current preset cycle; the PID control parameters include proportional parameters, integral parameters and differential parameters; wherein, before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to be reduced to a second preset range; according to the PID output signal, the output voltage is adjusted to be stable before the brake power supply is connected to the load, and stabilized to the target voltage within the first time after the brake power supply is connected to the load; the cost of converting the output voltage of the brake power supply is reduced; the output voltage of the brake power supply can be adjusted without modifying the circuit, and is suitable for brakes of different voltage models; and the accuracy of the output voltage of the brake power supply is effectively improved, overshoot is reduced, and control accuracy and stability are improved.

[0032] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0034] Figure 1 is a schematic diagram of voltage conversion of a brake power supply in an embodiment;

[0035] Figure 2 is a flow chart of a brake power supply control method in an embodiment;

[0036] Figure 3 is a schematic diagram of a PID control loop of a brake power supply output voltage in one embodiment;

[0037] Figure 4 The figure is a schematic diagram of the output voltage waveform of the brake power supply in an embodiment where PID segmented control is not adopted;

[0038] Figure 5 The figure is a schematic diagram of the output voltage waveform of the brake power supply using PID segmented control in one embodiment;

[0039] Figure 6 is a schematic diagram of voltage and current waveforms output by a brake power supply in an embodiment;

[0040] Figure 7 The figure is a structural block diagram of a brake power supply control device in an embodiment. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0042] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0043] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0044] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation, and may represent the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0045] Brake is a mechanical device, usually used in motor systems, which provides resistance or braking force when the motor stops running to prevent the load from moving unexpectedly or keep the load in a stable position. The brake power supply is used to provide power to the brake. When the brake power supply is connected to the brake, the brake opens to allow the motor to operate normally; when the brake power supply is disconnected from the brake, the brake stops the motor. Figure 1 It is a schematic diagram of the principle of the brake power supply in the embodiment of the present application converting the input voltage into the voltage required for the brake, wherein the input voltage of the brake power supply is 220V AC mains, which is converted to 310V through a pressure relay, a starting resistor relay, a starting resistor, and a rectifier device. The PID control module controls the MOS tube in the drive circuit by controlling the duty cycle of the PWM wave to adjust the output voltage to the target voltage for powering the brake.

[0046] The present application embodiment provides a brake power control method, such as Figure 2 As shown, the method comprises the following steps:

[0047] Step 201 : collecting the output voltage of the brake power supply in each preset cycle as a feedback voltage, and calculating the deviation between each feedback voltage and a target voltage.

[0048] Specifically, the output voltage of the brake power supply in each preset period can be collected by an analog-to-digital converter (ADC), the preset period is 150us, the output voltage is used as the feedback voltage, and the deviation between each feedback voltage and the target voltage set by the server is calculated by the PID control algorithm. The calculation formula is as follows:

[0049] Uerror = Utarget – Ureal (1)

[0050] The error Uerror in formula (1) is the difference between the target voltage Utarget and the feedback voltage Ureal.

[0051] Step 202, according to the deviation and the PID control parameters, calculate the PID change of each preset cycle, and accumulate the PID changes of all previous times to obtain the PID output signal of the current preset cycle; the PID control parameters include a proportional parameter, an integral parameter and a differential parameter; wherein, before the brake power supply is connected to the load, adjust the proportional parameter, the integral parameter and the differential parameter to a first preset range, and then control the differential parameter to be reduced to a second preset range.

[0052] In the embodiment of the present application, the PID control algorithm adopts incremental PID control, and specifically designs an incremental PID control algorithm suitable for the brake power supply. The voltage deviation Uerror calculated in step 201 is used as the input of the PID control. Since the PID control algorithm has a differential process, it is necessary to record the last voltage deviation Uerrorlast and the last voltage deviation Uerrorlastlast, and calculate the PID change pidincrement of each preset cycle by formula (2):

[0053] pidincrement=(Kp×(Uerror-Uerrorlast))+(Ki×Uerror)+(Kd×(Uerror-2×

[0054] Uerrorlastlast+Uerrorlast))(2)

[0055] Among them, Kp in formula (2) is the proportional parameter, Ki is the integral parameter, and Kd is the differential parameter. The calculated PID change pidincrement may be a positive value or a negative value.

[0056] By accumulating the PID change pidincrement, the PID output signal pidout of the current preset cycle can be obtained. The calculation formula is as follows:

[0057] pidout += pidincrement (3)

[0058] Among them, the adjustment of the proportional parameter Kp, the integral parameter Ki, and the differential parameter Kd follows the following method: before the brake power supply is connected to the load, the proportional parameter Kp, the integral parameter Ki, and the differential parameter Kd are adjusted to within the first preset range, and then the differential parameter Kd is controlled to be reduced to within the second preset range. That is, whenever the brake power supply is in a no-load state, a two-stage PID control parameter adjustment method is used for adjustment: first, the proportional parameter Kp, the integral parameter Ki, and the differential parameter Kd are each set to a value within their respective first preset ranges, and the first preset range of each parameter may be different. At this time, the calculated PID output signal can greatly reduce the overshoot of the output voltage, improve the output voltage accuracy, and achieve the stability of the output voltage. For example, the PID control parameter can stabilize the output voltage at a first voltage that deviates from the target voltage within a small range; then the differential parameter Kd is reduced to a value within the second preset range. At this time, the calculated PID output signal can improve the anti-interference of the output voltage. After that, the brake power supply is connected to the load, which can improve the overall robustness, make the output voltage less affected by the fluctuation of the input end, and greatly reduce the amplitude and time of the output voltage oscillation.

[0059] Step 203: According to the PID output signal, the output voltage is adjusted to be stable before the brake power supply is connected to the load, and stabilized to the target voltage within the first time after the brake power supply is connected to the load.

[0060] By adjusting the above two-stage PID control parameters, it is possible to ensure that the output voltage of the brake power supply is stable in the no-load state, and after connecting to the load, it can quickly stabilize to the target voltage, thereby avoiding brake abnormalities and accidents caused by fluctuations at the input end.

[0061] Exemplarily, before the brake power supply is connected to the load, the proportional parameter Kp, the integral parameter Ki and the differential parameter Kd are respectively set to the first proportional parameter Kp1, the first integral parameter Ki1 and the first differential parameter Kd1, so as to adjust the output voltage of the brake power supply to be stable at a first voltage 10V higher than the target voltage before the load is connected, and then the proportional parameter Kp, the integral parameter Ki and the differential parameter Kd are respectively set to the first proportional parameter Kp1, the first integral parameter Ki1 and the second differential parameter Kd2, where the second differential parameter Kd2 is smaller than the first differential parameter Kd1, so as to adjust the output voltage of the brake power supply to be stable at the target voltage within 10ms after the load is connected.

[0062] In one embodiment, adjusting the proportional parameter, the integral parameter and the differential parameter to within a first preset range includes adjusting the proportional parameter, the integral parameter and the differential parameter in sequence.

[0063] Specifically, first fix the integral parameter Ki and the differential parameter Kd to 0, and adjust the proportional parameter Kp. When the proportional parameter Kp is adjusted to Kp1 within the first preset range, the output voltage responds faster, but there is a large overshoot. Next, adjust the integral parameter Ki, gradually increase Ki to Ki1 within the first preset range, and the voltage output overshoot is reduced, but the output will jitter. Finally, adjust the differential parameter Kd, gradually increase Kd to Kd1 within the first preset range, and the system overshoot is reduced while the steady-state fluctuation is reduced, and the output voltage is stable.

[0064] The brake power supply control method in the embodiment of the present application realizes rapid stabilization of the brake power supply output voltage through incremental PID regulation and segmented adjustment of PID control parameters when the brake power supply is in a no-load state, and is applicable to motor brake power supplies in any field.

[0065] In one of the embodiments, the PID change pidincrement is controlled not to be higher than a maximum value and not to be lower than a minimum value to prevent it from changing too fast and affecting the stability of the PID control.

[0066] In one embodiment, the PID output signal pidout is controlled not to be higher than a maximum value. Since the PID output signal pidout is directly related to the duty cycle of the PWM wave, the value cannot be too large, otherwise the converted voltage will be too high and the power device MOS tube will be broken down.

[0067] In one embodiment, collecting the output voltage of the brake power supply in each preset cycle as the feedback voltage includes: collecting and recording the output voltage of the brake power supply in each preset cycle, adding the output voltage of the current preset cycle and the output voltage of previous preset cycles, taking the average value and normalizing, and using the obtained voltage data as the feedback voltage input to the PID control. In this way, the sampled output voltage can be filtered.

[0068] like Figure 3As shown in the figure, a schematic diagram of the PID control loop for the target voltage output by the brake power supply is shown. Among them, the target voltage is the given signal of the PID control module, and the input of the PID control module is the deviation e(t) between the feedback voltage and the target voltage in the t-th preset cycle. The deviation is adjusted by the PID control algorithm and the corresponding proportional parameter Kp, integral parameter Ki, and differential parameter Kd to output the adjustment variable Δu(t). The adjustment variable will act on the PWM drive circuit, that is, adjust the duty cycle of the PWM wave. The duty cycle of the PWM wave will be directly related to the MOS tube in the drive circuit. The higher the duty cycle of the PWM wave, the longer the conduction time of the MOS tube, and the higher the output voltage of the drive circuit, and vice versa. The output voltage of the driving circuit is input into the ADC sampling module through the operational amplifier step-down circuit. The output voltage value of the current t-th preset cycle collected is added to the previous output voltage values, i.e., the (t-1)th to (ti)th times, and then the average value and normalization processing are performed to obtain the feedback voltage. The deviation is processed with the target voltage and used as the input of the PID control module to realize the cyclic dynamic adjustment of the algorithm, and finally realize the stable output of the brake power supply output voltage to ensure the normal operation of the brake.

[0069] The PID control module of the brake power supply in the embodiment of the present application adopts an incremental PID control method, compares the target voltage with the feedback voltage currently output by the brake power supply, and adjusts the output voltage of the brake power supply by changing the duty cycle of the PWM wave. The output voltage of the brake power supply can be adjusted without modifying the circuit, and can be adapted to brakes of different voltage models. The incremental PID adjustment has the characteristics of fast adjustment speed, stable output, and strong anti-interference ability, which makes the voltage output by the brake power supply more stable, with smaller overshoot, and effectively protects the brake.

[0070] In one embodiment, the brake power supply control method is applied to an elevator brake, the brake power supply is connected to the elevator brake through a brake switch, and before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to decrease to a second preset range, including: during the closing process of the brake switch, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to decrease to a second preset range. The closing process of the brake switch is the time from the brake switch receiving the closing instruction to the completion of the closing action. When the brake switch completes the closing action, the brake power supply changes from no-load to load state.

[0071] Since the elevator operation process requires frequent stopping and starting, when the elevator control system controls the elevator to stop, that is, controls the brake switch to be disconnected, so that the elevator brake can stop the elevator host and stop the elevator; when the elevator control system controls the elevator to stop and start, that is, controls the brake switch to be closed, so that the elevator brake can be opened to allow the elevator host to operate normally and start the elevator. Therefore, in the field of elevators, it is particularly necessary to control the stability and anti-interference of the output voltage at the moment of the brake switch closing, so as to avoid the influence of the brake power input end on the elevator brake at the moment of the brake power supply connection, thereby ensuring the safety of the elevator operation. Therefore, by using the control timing of the brake switch from receiving the closing instruction to completing the closing action, the proportional parameter, the integral parameter and the differential parameter are adjusted to the first preset range, and then the differential parameter is controlled to be reduced to the second preset range, which can effectively improve the accuracy of the brake power supply output voltage, reduce the overshoot voltage of the brake power supply, thereby reducing the current at the moment of the brake switch closing, and effectively protect the elevator brake and brake power supply. In this embodiment, the brake switch is a brake contactor, and its control timing from receiving the closing instruction issued by the elevator control system to completing the closing action is 100ms.

[0072] In one embodiment, the adjustment of the proportional parameter, the integral parameter and the differential parameter to a first preset range, and then controlling the differential parameter to decrease to a second preset range includes: adjusting the proportional parameter to a range of 0.01 to 0.2, the integral parameter to a range of 0.005 to 0.015, and the differential parameter to a range of 0.1 to 0.5; and then controlling the differential parameter to decrease to a range of 0.01 to 0.02. It has been verified that the above data range can ensure that the output voltage is adjusted during the closing process of the brake switch, so as to achieve a stable output voltage when the brake switch is in a no-load state, thereby improving the accuracy of the brake power supply output when the elevator starts running; and the instantaneous current of the load connection, that is, the instantaneous current of the brake switch when the brake switch is closed, is small, and the output voltage can quickly stabilize to the target voltage, and the oscillation amplitude is small.

[0073] Specifically, the process of adjusting the PID control parameters in the first section is: first fix the integral parameter Ki and the differential parameter Kd to 0, adjust the proportional parameter Kp, when the proportional parameter Kp is between 0.01 and 0.2, the output voltage of the brake power supply responds faster, but there is a large overshoot; next adjust the integral parameter Ki, gradually increase the integral parameter Ki to between 0.005 and 0.015, the voltage output overshoot is reduced, and the output will have jitter; finally adjust the differential parameter Kd, gradually increase the differential parameter Kd to between 0.1 and 0.5, the system overshoot is reduced and the steady-state fluctuation is reduced, but the robustness of the system is weakened. If there is fluctuation at the input end after the brake is opened, the output voltage will oscillate, causing the brake to work abnormally and cause an accident; then control the differential parameter Kd to be reduced to the range of 0.01 to 0.02, while ensuring that the system overshoot is reduced, the stability of the system is also guaranteed. When the embodiment of the present application switches to the second stage of adjusting the PID control parameters, that is, adjusting the differential parameter Kd for the second time, the system is already in a stable output state. It only needs to improve the robustness of the system and enhance its anti-interference ability, without considering the overshoot and response speed of the output voltage.

[0074] See also Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the output voltage waveform of the brake power supply without PID segmented control. Figure 5 The figure is a schematic diagram of the output voltage waveform of the brake power supply using PID segmented control. Comparative analysis shows that the voltage overshoot is reduced by about 30V by using segmented PID control parameters, which improves the control accuracy and effectively reduces the current when the contactor is closed, effectively protecting the elevator brake and brake power supply. In the figure, the moment when the relay is closed is when the brake switch is closed; this time point is the end point of the control sequence for controlling the closing of the brake switch.

[0075] In one of the embodiments, before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to within a first preset range, and before the differential parameter is controlled to be reduced to within a second preset range, the method further includes: within N preset cycles, controlling the PID output signal to be a first preset value, and collecting the output current of the brake power supply, the output voltage adjusted by the first preset value is less than the target voltage; when the output current is greater than the current threshold, controlling the input end of the brake power supply to be disconnected.

[0076] Specifically, in order to prevent misoperation during the installation process, which may cause the brake power supply output voltage to be short-circuited by mistake, resulting in damage to the brake power supply and the brake, the embodiment of the present application also implements a corresponding short-circuit overcurrent protection mechanism. Since the PID control function is in the preset periodic function, the control has a certain delay. If the brake power supply is short-circuited at the beginning, the feedback voltage is always 0. At this time, the system becomes open-loop control, and the PWM wave duty ratio is relatively high, resulting in a large output voltage of the MOS tube, a short circuit, and damage to the brake power supply.

[0077] In order to make up for the defects of PID control delay, the present application performs short-circuit overcurrent detection within N preset periods before each two-stage adjustment of the PID control parameters. For example, the preset period is 150us, and N is 5. During this period, the PID output signal is controlled to be a first preset value, so that the duty cycle of PWM is a smaller value. The output voltage adjusted by the first preset value is less than the target voltage and is only used for overcurrent detection. By collecting the output current of the brake power supply to determine whether the brake power supply output is short-circuited, when the output current is greater than the current threshold, it is determined that the brake power supply is short-circuited, and the input end of the brake power supply is controlled to be disconnected, thereby effectively protecting the brake power supply and the brake.

[0078] In the brake power control method of the embodiment of the present application, the brake power chip has an ADC sampling function, and is configured with two sampling channels to sample voltage and current respectively, and the reference voltage is 3.3V. Figure 6 The figure shows the voltage and current waveforms of the brake power supply output. By collecting the output voltage and output current of the brake power supply in each preset cycle, the aging trend of the brake output capacitor and output resistor is determined by calculation, so that maintenance personnel can replace the brake in time.

[0079] In one embodiment, the method further includes collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the product of the output voltage and the output current after the brake switch is closed and before the output current stabilizes as the output capacitance of each preset cycle; calculating the ratio of the difference between the output capacitance and the initial capacitance in each preset cycle to the initial capacitance, and comparing the ratios of multiple preset cycles to determine the aging trend of the output capacitance.

[0080] Specifically, the elevator provides brake power through the brake power board, which is equipped with a brake power chip and an analog-to-digital converter ADC. The output voltage of the brake power board must pass through the brake contactor and then reach the elevator brake. After the brake switch is closed, that is, the brake contactor is energized, the output voltage first charges the capacitor C in the brake. At this time, the output voltage U and output current I at each time point within the Δt time are sampled by the analog-to-digital converter ADC, and the capacity of the capacitor C is calculated. The capacity Qc of the capacitor C is calculated using the following formula:

[0081] Qc=∫(U×I)dt (4)

[0082] Exemplarily, the power board timer interrupt cycle, i.e., the preset cycle, is configured to be 150us. At the moment when the brake contactor is energized, the product of the output voltage U and the output current I within each 150us is summed until the current reaches a stable value. At this time, the brake is opened and the elevator runs. When the elevator is installed, the initial capacity of the brake capacitor C is calculated as Qc1 and written into the memory FLASH of the brake power chip to prevent power loss. Later, each time the elevator runs, after the brake switch is closed and before the output current stabilizes, that is, Figure 6 Between the two dotted lines in the figure, the capacity Qc2 of the capacitor C in the current preset cycle is calculated to determine the aging trend of the output capacitor. The embodiment of the present application uses the following formula to calculate the aging degree of the brake capacitor AngingPencent_C:

[0083] AngingPencent_C = abs(Qc2- Qc1) / Qc1 (5)

[0084] Among them, the value of the brake capacitor aging degree AngingPencent_C is between 0-1, and the larger the value, the more serious the aging of the capacitor.

[0085] In one of the embodiments, the method further includes collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the ratio of the output voltage to the output current after the brake switch is closed and the output current is stable as the output resistance of each preset cycle; calculating the ratio of the difference between the output resistance and the initial resistance in each preset cycle to the initial resistance, and comparing the ratios of multiple preset cycles to determine the aging trend of the output resistance.

[0086] Specifically, after the brake opening current stabilizes, the output voltage U and output current I are detected every 150us, and the resistance R of the brake is calculated:

[0087] R=U / I (6)

[0088] The initial brake resistance is R1, which is written into the memory FLASH of the brake power chip. Figure 6 After the dotted line on the right side of the graph, the current brake resistance R2 is calculated, and the brake resistance aging degree AngingPencent_R is calculated using the following formula:

[0089] AngingPencent_R = abs(R2-R1) / R1 (7)

[0090] Among them, the value of the brake resistance aging degree AngingPencent_R is greater than or equal to 0, and the larger the value is, the higher the resistance aging degree is.

[0091] The present application also provides a brake power supply control device, such as Figure 7 As shown, it includes a data acquisition module 10 and a PID control module 20. The data acquisition module 10 is used to collect the output voltage of the brake power supply of each preset cycle and feed it back to the PID control module 20. The PID control module 20 is used to calculate the deviation between each output voltage and the target voltage; and according to the deviation and the PID control parameter, the PID change of each preset cycle is calculated, and the previous PID changes are accumulated to obtain the PID output signal of the current preset cycle; the PID control parameter includes a proportional parameter, an integral parameter and a differential parameter; according to the PID output signal, the output voltage is adjusted to the target voltage; it is also used to adjust the proportional parameter, the integral parameter and the differential parameter to a first preset range before the brake power supply is connected to the load, and then control the differential parameter to decrease to a second preset range.

[0092] It should be noted that the above modules can be functional modules or program modules, and can be implemented by software or hardware. For modules implemented by hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0093] In this embodiment, an electronic device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0094] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0095] Optionally, in this embodiment, the processor may be configured to execute the steps in any of the above method embodiments through a computer program.

[0096] It should be noted that the specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementation modes, and will not be repeated in this embodiment.

[0097] In addition, in combination with the brake power control method provided in the above embodiments, a storage medium may be provided in this embodiment to implement the method. The storage medium stores a computer program; when the computer program is executed by a processor, any brake power control method in the above embodiments is implemented.

[0098] An embodiment of the present application also provides a brake power supply, which includes a controller and a drive circuit, and the drive circuit includes a switch tube. The controller is used to execute the brake power supply control method described in any one of the above embodiments to adjust the duty cycle of the switch tube through the PID output signal, thereby adjusting the output voltage of the drive circuit to the target voltage.

[0099] An embodiment of the present application also provides an elevator brake system, comprising a brake power supply, a brake switch and an elevator brake as described in any one of the above embodiments connected in sequence; the elevator brake system also includes an elevator control system and a server, the controller and the brake switch are both controlled by the elevator control system, the controller is communicatively connected to the server, and the server is used to set the target voltage, and receive and display the output voltage and output current of the brake power supply for each preset cycle.

[0100] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A brake power supply control method, characterized in that: The method comprises: Collecting the output voltage of the brake power supply in each preset cycle as a feedback voltage, and calculating the deviation between each feedback voltage and a target voltage; According to the deviation and PID control parameters, the PID change amount of each preset cycle is calculated, and the PID change amounts of all previous cycles are accumulated to obtain the PID output signal of the current preset cycle; the PID control parameters include proportional parameters, integral parameters and differential parameters; Wherein, before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and then the differential parameter is controlled to decrease to a second preset range; According to the PID output signal, the output voltage is adjusted to be stable before the brake power supply is connected to the load, and is stabilized to the target voltage within the first time after the brake power supply is connected to the load.

2. The method according to claim 1, characterized in that The brake power supply control method is applied to an elevator brake, wherein the brake power supply is connected to the elevator brake through a brake switch, and before the brake power supply is connected to a load, the proportional parameter, the integral parameter and the differential parameter are adjusted to within a first preset range, and then the differential parameter is controlled to decrease to within a second preset range, including: During the closing process of the brake switch, the proportional parameter, the integral parameter and the differential parameter are adjusted to be within a first preset range, and then the differential parameter is controlled to decrease to be within a second preset range.

3. The method according to claim 2, characterized in that The adjusting the proportional parameter, the integral parameter and the differential parameter within a first preset range, and then controlling the differential parameter to decrease within a second preset range comprises: Adjust the proportional parameter to a range of 0.01 to 0.2, the integral parameter to a range of 0.005 to 0.015, and the differential parameter to a range of 0.1 to 0.5; Then the differential parameter is controlled to be reduced to within the range of 0.01 to 0.

02.

4. The method according to claim 1, characterized in that: Before the brake power supply is connected to the load, the proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, and before the differential parameter is controlled to decrease to a second preset range, the method further includes: In N preset cycles, the PID output signal is controlled to be a first preset value, and the output current of the brake power supply is collected, and the output voltage adjusted by the first preset value is less than the target voltage; When the output current is greater than a current threshold, the input end of the brake power supply is controlled to be disconnected.

5. The method according to claim 2, characterized in that: The method further comprises: Collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the product of the output voltage and the output current after the brake switch is closed and before the output current stabilizes as the output capacitance of each preset cycle; The ratio of the difference between the output capacitance and the initial capacitance in each preset cycle to the initial capacitance is calculated, and the ratios in multiple preset cycles are compared to determine the aging trend of the output capacitance.

6. The method according to claim 2, characterized in that The method further comprises: Collecting the output voltage and output current of the brake power supply in each preset cycle, and calculating the ratio of the output voltage to the output current after the brake switch is closed and the output current is stable as the output resistance of each preset cycle; The ratio of the difference between the output resistance and the initial resistance in each preset cycle to the initial resistance is calculated, and the ratios in multiple preset cycles are compared to determine the aging trend of the output resistance.

7. The method according to claim 1, characterized in that The proportional parameter, the integral parameter and the differential parameter are adjusted to a first preset range, include, The proportional parameter, the integral parameter and the differential parameter are adjusted in sequence.

8. A brake power supply control device, characterized in that: include: A data acquisition module is used to collect the output voltage of the brake power supply in each preset cycle and feed it back to the PID control module; The PID control module is used to calculate the deviation between each output voltage and the target voltage; And according to the deviation and PID control parameters, the PID change of each preset cycle is calculated, and the previous PID changes are accumulated to obtain the PID output signal of the current preset cycle; the PID control parameters include proportional parameters, integral parameters and differential parameters; according to the PID output signal, the output voltage is adjusted to the target voltage; it is also used to adjust the proportional parameter, the integral parameter and the differential parameter to a first preset range before the brake power supply is connected to the load, and then control the differential parameter to decrease to a second preset range.

9. A brake power supply, characterized in that: The brake power supply includes a controller and a drive circuit, the drive circuit includes a switch tube, and the controller is used to execute the brake power supply control method as described in any one of claims 1 to 7, so as to adjust the duty cycle of the switch tube through the PID output signal, thereby adjusting the output voltage of the drive circuit to the target voltage.

10. An elevator brake system, characterized in that: comprising a brake power supply, a brake switch and an elevator brake as claimed in claim 9 connected in sequence; The elevator brake system also includes an elevator control system and a server. The controller and the brake switch are both controlled by the elevator control system. The controller is communicatively connected to the server. The server is used to set the target voltage, and receive and display the output voltage and output current of the brake power supply for each preset cycle.

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