Bypass switching control method and device, computer readable medium and program product

Abstract

The embodiment of the invention discloses a bypass switching control method and device, a computer readable medium and a program product. A specific embodiment of the method comprises the steps of performing soft start operation on a target motor through a soft starter corresponding to the target motor; in the soft start operation process, the zero crossing point time of the current is detected to serve as first zero crossing point time; sampling the input voltage of the power grid in real time to obtain sampling information; according to the sampling information, generating zero crossing point time of the power grid voltage as second zero crossing point time; generating a compensation zero-crossing point time according to the first zero-crossing point time and the second zero-crossing point time; and controlling a bypass contactor corresponding to the target motor to operate according to the compensation zero crossing point time. According to the embodiment, the zero crossing point time error of the phase current caused by power grid voltage interference can be reduced, so that false triggering of overtime protection is reduced, and the situation that the soft starter cannot be normally started is reduced.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to the technical field of power electronic converters, and in particular, to a bypass switching control method, device, computer-readable medium, and program product. Background Art

[0002] A soft starter is a motor control device that integrates functions such as soft starting, soft stopping, light-load energy saving, and multiple protection functions of a motor. It can not only start the motor smoothly without impact throughout the starting process, but also adjust parameters during the starting process according to the characteristics of the motor load, such as the current limiting value, starting time, etc. After confirming the completion of soft start, it is necessary to quickly switch the bypass contactor. Currently, the commonly used method to confirm the completion of soft start is to directly detect the zero-crossing time of the current, or indirectly detect the zero-crossing time of the phase current by detecting the voltage across two antiparallel thyristors.

[0003] However, when using the above methods, there are often the following technical problems: The above two detection and control methods are very susceptible to grid voltage interference and abnormal detection. When designing a soft starter, in order to avoid damage to the thyristor due to long-term conduction and heating, a soft start protection time is usually set (that is, soft start needs to be completed within a specified time, and if it times out, the start fails and a fault shutdown is reported), resulting in the detected zero-crossing time of the voltage or current may always be greater than the soft start protection time (for example, 800 us), thus triggering the start timeout protection, and ultimately causing the soft starter to fail to start normally.

[0004] The above information disclosed in this background art section is only used to enhance the understanding of the background of the inventive concept, and thus, it may include information that does not form the prior art known to those of ordinary skill in the art in this country. Summary of the Invention

[0005] The content part of the present disclosure is used to briefly introduce concepts, which will be described in detail in the following detailed implementation part. The content part of the present disclosure is not intended to identify the key features or essential features of the claimed technical solution, nor is it intended to be used to limit the scope of the claimed technical solution.

[0006] Some embodiments of the present disclosure propose a bypass switching control method, device, computer-readable medium, and program product to solve one or more of the technical problems mentioned in the above background art section.

[0007] In a first aspect, some embodiments of the present disclosure provide a bypass switching control method, which includes: performing a soft start operation on the target motor through a soft starter corresponding to the target motor; during the soft start operation, detecting the zero-crossing time of the current as the first zero-crossing time; performing real-time sampling on the grid input voltage to obtain sampling information; generating the zero-crossing time of the grid voltage as the second zero-crossing time according to the sampling information; generating a compensated zero-crossing time according to the first zero-crossing time and the second zero-crossing time; and controlling the bypass contactor corresponding to the target motor to operate according to the compensated zero-crossing time.

[0008] Optionally, the performing a soft start operation on the target motor through a soft starter corresponding to the target motor includes: using thyristors included in the soft starter to adjust the voltage of the target motor so that the current of the target motor increases.

[0009] Optionally, the method further includes: controlling the thyristors to stop operating in response to the successful operation of the bypass contactor.

[0010] Optionally, the method further includes: controlling the bypass contactor to disconnect in response to detecting a shutdown operation corresponding to the target motor; reducing the motor supply voltage of the target motor through the soft starter so that the target motor shuts down smoothly.

[0011] Optionally, the performing real-time sampling on the grid input voltage to obtain sampling information includes: performing a step-down process on the grid input voltage to obtain the processed grid input voltage; passing the processed grid input voltage through the analog-to-digital converter module of the control board to obtain each sampled voltage as the sampling information.

[0012] Optionally, the soft starter includes two antiparallel thyristors; and the detecting the zero-crossing time of the current as the first zero-crossing time during the soft start operation includes: detecting the voltages across the two thyristors; controlling the two thyristors to turn off in response to detecting that the phase current of the circuit meets a preset threshold condition, where the voltage difference across each thyristor is greater than a preset threshold in the off state; controlling the two thyristors to turn on in response to detecting that the phase current of the circuit does not meet the preset threshold condition, where the voltage difference across each thyristor is less than a preset voltage in the on state; outputting a voltage pulse square wave signal based on the detected voltages; and generating the zero-crossing time of the current as the first zero-crossing time based on the voltage pulse square wave signal.

[0013] Optionally, generating the zero-crossing time of the current as the first zero-crossing time based on the above voltage pulse square wave signal includes: sending the above voltage pulse square wave signal to the timer module of the control board; generating the zero-crossing time of the current as the first zero-crossing time through the above timer module.

[0014] In a second aspect, some embodiments of the present disclosure provide an electronic device, including: one or more processors; a target motor for providing power; a storage device on which one or more programs are stored, and when the one or more programs are executed by the one or more processors, the one or more processors implement the method described in any implementation manner of the first aspect above.

[0015] In a third aspect, some embodiments of the present disclosure provide a computer-readable medium on which a computer program is stored, and when the program is executed by a processor, the method described in any implementation manner of the first aspect above is implemented.

[0016] In a fourth aspect, some embodiments of the present disclosure provide a computer program product, including a computer program, and when the computer program is executed by a processor, the method described in any implementation manner of the first aspect above is implemented.

[0017] The above-mentioned various embodiments of the present disclosure have the following beneficial effects: Through the bypass switching control method of some embodiments of the present disclosure, the zero-crossing time error of the phase current caused by grid voltage interference can be reduced, thereby reducing the false triggering of over-time protection and reducing the situation where the soft starter cannot start normally. Specifically, the reason for the abnormal start of the soft starter is that the two detection and control methods involved in the background technology are very susceptible to grid voltage interference and detect abnormally. When designing the soft starter, in order to avoid the thyristor from being damaged due to long-term conduction and heating, a soft start protection time is usually set, resulting in the zero-crossing time of the detected voltage or current may always be greater than the soft start protection time, thereby triggering the start over-time protection, and ultimately resulting in the abnormal start of the soft starter. Based on this, in the bypass switching control method of some embodiments of the present disclosure, first, the target motor is soft-started by the soft starter corresponding to the target motor. Then, during the above soft start operation, the zero-crossing time of the current is detected as the first zero-crossing time. Thus, the zero-crossing time of the current can be detected during the soft start of the target motor. Next, the grid input voltage is sampled in real time to obtain sampling information. Thus, the continuously changing voltage can be sampled discretely in real time. Secondly, according to the above sampling information, the zero-crossing time of the grid voltage is generated as the second zero-crossing time. Thus, the zero-crossing time of the grid voltage can be determined. Then, according to the above first zero-crossing time and the above second zero-crossing time, a compensated zero-crossing time is generated. Thus, the zero-crossing time of the current can be compensated by the zero-crossing time of the grid voltage, and the zero-crossing time error of the phase current caused by grid voltage interference can be reduced. Finally, according to the above compensated zero-crossing time, the bypass contactor corresponding to the target motor is controlled to operate. Thus, it is possible to avoid the situation where the detected zero-crossing time of the voltage or current is always greater than the soft start protection time and trigger the start over-time protection, thereby reducing the false triggering of the over-time protection, quickly switching the bypass contactor, and further reducing the situation where the soft starter cannot start normally. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In combination with the accompanying drawings and referring to the following specific embodiments, the above and other features, advantages, and aspects of the various embodiments of the present disclosure will become more obvious. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the elements and elements are not necessarily drawn to scale.

[0019] Figure 1 is a flowchart according to some embodiments of the bypass switching control method of the present disclosure;

[0020] Figure 2 is a schematic diagram of current zero-crossing detection according to some embodiments of the bypass switching control method of the present disclosure;

[0021] Figure 3 It is a schematic diagram of the zero-crossing detection waveform of the normal grid input voltage of the bypass switching control method according to some embodiments of the present disclosure;

[0022] Figure 4 It is a schematic diagram of the zero-crossing detection waveform of the grid input voltage distortion of the bypass switching control method according to some embodiments of the present disclosure;

[0023] Figure 5 It is a schematic structural diagram of an electronic device suitable for implementing some embodiments of the present disclosure. Detailed Embodiments

[0024] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although some embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided to more thoroughly and completely understand the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for exemplary purposes and are not used to limit the protection scope of the present disclosure.

[0025] In addition, it should be noted that for the sake of convenience of description, only parts related to the relevant invention are shown in the drawings. Without conflict, the embodiments in the present disclosure and the features in the embodiments can be combined with each other.

[0026] It should be noted that concepts such as "first" and "second" mentioned in the present disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or mutual dependence relationship of the functions performed by these devices, modules or units.

[0027] It should be noted that the modifications of "one" and "multiple" mentioned in the present disclosure are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly specified in the context, it should be understood as "one or more".

[0028] The names of the messages or information exchanged between multiple devices in the embodiments of the present disclosure are only for illustrative purposes and are not used to limit the scope of these messages or information.

[0029] The present disclosure will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0030] Figure 1 Flow 100 of some embodiments of the bypass switching control method according to the present disclosure is shown. The bypass switching control method includes the following steps:

[0031] Step 101, perform a soft start operation on the target motor through the soft starter corresponding to the target motor.

[0032] In some embodiments, the execution subject of the bypass switching control method (such as an electronic device including a motor) can perform a soft start operation on the above-mentioned target motor through the soft starter corresponding to the target motor. Among them, the above-mentioned target motor can be a motor controllable by the above-mentioned execution subject. The above-mentioned execution subject can be any device equipped with a motor. For example, the above-mentioned execution subject can be an air conditioner compressor or a crane. The above-mentioned soft starter can be a device for controlling the start and stop of an alternating current induction motor (mainly a three-phase asynchronous motor). By adjusting the voltage or current when the motor starts, the motor speed is gradually increased to achieve the soft start of the motor, thus avoiding the impact current and mechanical stress generated at the moment of start. The above-mentioned soft starter can be a bypass type soft starter, which can achieve efficient operation of the motor after startup through the cooperation of the soft starter and the bypass contactor. The bypass type soft start scheme can not only reduce the motor starting current, but also reduce the energy loss and heat generation caused by the long-term operation of the thyristor. Since the thyristor does not need to work for a long time, but only works for a short time during the startup process, there is no need to design a large heat dissipation and cooling device for the thyristor, thus greatly reducing the volume and cost of the soft starter. In practice, thyristors can be used for voltage regulation, and the voltage is gradually increased by adjusting the conduction angle to make the motor current rise smoothly. The soft starter gradually increases the voltage of the above-mentioned target motor, thereby achieving the smooth start of the motor and limiting the starting current.

[0033] Step 102, during the soft start operation, detect the zero-crossing time of the current as the first zero-crossing time.

[0034] In some embodiments, the above-mentioned execution subject can detect the zero-crossing time of the current as the first zero-crossing time during the above-mentioned soft start operation. In practice, the above-mentioned execution subject can detect the zero-crossing time of the current as the first zero-crossing time by directly detecting the phase current. The zero-crossing time can be the duration of the zero-crossing point.

[0035] As Figure 2 shown, when the current approaches 0A, the output square wave is at a low level, otherwise it is at a high level, and t1 is the zero-crossing time. When the grid voltage is normal and distortion-free, as Figure 3 the simulation waveform, as the conduction angle of the thyristor gradually increases, the zero-crossing time of the phase current waveform gradually decreases, and the low-level time of the converted square wave pulse signal also becomes smaller and smaller. When the thyristor is fully conducting, the square wave signal becomes fully high level, indicating that the soft start stage is completed. Figure 3 The bar chart in

[0036] Figure 4 Figure 4The simulation waveform shows that due to the distortion of the grid input voltage all the time, the zero-crossing time of the phase current is prolonged. After the thyristors are fully turned on, the detected zero-crossing time of the phase current is about 1.16 ms, which is still greater than the soft-start protection time of 800 μs. Eventually, the soft starter fails to switch to bypass, resulting in a startup failure.

[0037] Optionally, the above soft starter may include two antiparallel thyristors.

[0038] In some optional implementation manners of some embodiments, the above execution entity may detect the zero-crossing time of the current as the first zero-crossing time during the above soft-start operation through the following steps:

[0039] The first step is to detect the voltages across the two thyristors.

[0040] The first step is to control the two thyristors to turn off in response to detecting that the phase current of the circuit meets the preset threshold condition. Wherein, in the off state, the voltage difference across each thyristor is greater than the preset threshold. The above preset threshold condition may be that the difference between the phase current and 0 A is less than the preset current magnitude. The preset current magnitude can be set to be greater than 0 and close to 0, so that the two thyristors can be controlled to turn off and cut off when the phase current is close to 0 A. The above preset threshold may be 0 V. After the thyristors are turned off and cut off, a voltage difference will be generated across the thyristors.

[0041] The second step is to control the two thyristors to turn on in response to detecting that the phase current of the circuit does not meet the above preset threshold condition. Wherein, in the on state, the voltage difference across each thyristor is less than the preset voltage. The preset voltage can be set to be greater than 0 and close to 0. In the on state of the thyristor, the voltage difference across each thyristor is close to 0 V. Thus, the two thyristors can be controlled to turn on when the phase current is greater than 0 A.

[0042] The third step is to output a voltage pulse square wave signal based on the detected voltage. In practice, a hardware zero-crossing detection circuit can be used. When there is voltage across the thyristor, a low level is output, and when the thyristor is on and there is no voltage across it, a high level is output to obtain the voltage pulse square wave signal.

[0043] In the fourth step, based on the above voltage pulse square wave signal, generate the zero-crossing time of the current as the first zero-crossing time. In practice, the above voltage pulse square wave signal can be sent to the timer module of the control board. The timer module of the control board can refer to a functional module built into the control board for setting and controlling various time parameters, including delay time, cycle time, etc. Then, through the above timer module, the zero-crossing time of the current can be generated as the first zero-crossing time. The counter in the timer module can record time. When the zero-crossing of the current is detected, the current count value can be captured. According to the captured count value and the timer clock frequency, the zero-crossing time can be generated. For example, the ratio of the captured count value to the timer clock frequency can be determined as the zero-crossing time of the current.

[0044] Step 103: Perform real-time sampling on the grid input voltage to obtain sampling information.

[0045] In some embodiments, the above execution entity can perform real-time sampling on the grid input voltage to obtain sampling information. In practice, the grid input voltage can be sampled in real time based on a preset sampling frequency to obtain each sampled voltage as sampling information. For example, the above preset sampling frequency can be 80 kHz.

[0046] In some optional implementation manners of some embodiments, the grid input voltage can be subjected to step-down processing to obtain the processed grid input voltage. In practice, the grid input voltage can be reduced to the target voltage by means of resistor voltage division and operational amplifier attenuation. The target voltage can be the working voltage adapted to the above target motor. For example, the above target voltage can be 3.3 V. Then, the above processed grid input voltage passes through the analog-to-digital converter module of the control board to obtain each sampled voltage as sampling information. The control board can be an MCU control board. The analog-to-digital converter module can be the ADC module of the control board. The analog-to-digital converter module can convert a continuously varying analog signal into a discrete digital signal for digital processing. The analog-to-digital converter module can sample the grid input voltage in real time at a preset sampling frequency to obtain each sampled voltage as sampling information. Thus, real-time sampling of the grid input voltage can be performed through the analog-to-digital converter module.

[0047] Step 104: Generate the zero-crossing time of the grid voltage as the second zero-crossing time according to the sampling information.

[0048] In some embodiments, the above-mentioned execution entity may generate the zero-crossing time of the grid voltage as the second zero-crossing time according to the above-mentioned sampling information. In practice, the zero-crossing time of the grid voltage can be detected by directly detecting the voltage waveform as the second zero-crossing time. When the grid voltage is undistorted, the calculated second zero-crossing time is close to 0. When the grid voltage is distorted, the actual zero-crossing time of the grid voltage can be calculated.

[0049] Step 105: Generate a compensated zero-crossing time according to the first zero-crossing time and the second zero-crossing time.

[0050] In some embodiments, the above-mentioned execution entity may generate a compensated zero-crossing time according to the above-mentioned first zero-crossing time and the above-mentioned second zero-crossing time. In practice, the difference between the above-mentioned first zero-crossing time and the above-mentioned second zero-crossing time can be determined as the compensated zero-crossing time.

[0051] Step 106: Control the bypass contactor corresponding to the target motor to operate according to the compensated zero-crossing time.

[0052] In some embodiments, the above-mentioned execution entity may control the bypass contactor corresponding to the above-mentioned target motor to operate according to the above-mentioned compensated zero-crossing time. The bypass contactor can be an electrical component that can be used to provide a bypass in a circuit to protect other components in the circuit from overload or short circuit. In practice, in response to determining that the above-mentioned compensated zero-crossing time is less than the soft start protection time, switch to operate the bypass contactor corresponding to the above-mentioned target motor. For example, the soft start protection time can be 800 us.

[0053] Optionally, the above-mentioned execution entity may control the thyristor to stop operating in response to the successful operation of the above-mentioned bypass contactor. Thus, the thyristor can be controlled to stop working after successfully switching to the bypass contactor. At this time, the target motor can be directly powered by the grid, and the thyristor enters the off state, avoiding energy loss and heat dissipation problems caused by long-term power-on.

[0054] Optionally, the above-mentioned execution entity may control the above-mentioned bypass contactor to disconnect in response to detecting a stop operation corresponding to the above-mentioned target motor. Wherein, the above-mentioned stop operation can be an operation to turn off the motor. For example, the motor can be turned off by a button on the device or by a control on the screen. Then, the motor supply voltage of the above-mentioned target motor can be reduced by the above-mentioned soft starter so that the above-mentioned target motor stops smoothly. In practice, the conduction angle of the thyristor included in the above-mentioned soft starter can be controlled to gradually reduce the motor supply voltage to achieve smooth shutdown. For example, the motor supply voltage can be reduced at a preset voltage reduction rate to achieve smooth shutdown.

[0055] Optionally, a voltage sensor may be connected to the input end of the above-mentioned target motor. A current sensor may be installed on the above-mentioned target motor. A rotational speed detector may be installed on the motor shaft of the above-mentioned target motor. For example, the rotational speed detector may be an optical encoder, and the rotational speed may be detected through a grating. A temperature sensor may be set at a preset position of the above-mentioned target motor. The preset position may be a key part of the motor or the soft starter. For example, the preset position may be the winding or the heat sink position. A force sensor may be set on the motor drive chain of the above-mentioned target motor. A vibration sensor may be set at the motor housing of the above-mentioned target motor. For example, the vibration sensor may include at least one of the following: an accelerometer, a laser vibrometer, and a piezoelectric sensor. The accelerometer can be used to measure the vibration acceleration of the motor or the structure. The laser vibrometer can be used for non-contact measurement of vibration displacement. The piezoelectric sensor can be used for measurement of high-frequency vibration.

[0056] Optionally, the above-mentioned execution entity may also respond to detecting a shutdown operation corresponding to the above-mentioned target motor and execute the following loop steps:

[0057] First step, collect voltage through the above-mentioned voltage sensor.

[0058] Second step, collect current through the above-mentioned current sensor.

[0059] Third step, collect the motor rotational speed through the above-mentioned rotational speed detector.

[0060] Fourth step, collect the motor temperature through the above-mentioned temperature sensor.

[0061] Fifth step, collect the motor load through the above-mentioned force sensor. Here, the mechanical load may include the magnitude of the force detected by the force sensor.

[0062] Sixth step, collect vibration information through the above-mentioned vibration sensor. The vibration information may include but is not limited to at least one of the following: vibration acceleration, vibration displacement.

[0063] Seventh step, combine the above-mentioned voltage, the above-mentioned current, the above-mentioned motor rotational speed, the above-mentioned motor temperature, the above-mentioned motor load, and the above-mentioned vibration information into multi-dimensional features. In practice, the above-mentioned voltage, the above-mentioned current, the above-mentioned motor rotational speed, the above-mentioned motor temperature, the above-mentioned motor load, and the above-mentioned vibration information may be concatenated into multi-dimensional features.

[0064] Eighth step, determine the combined multi-dimensional features within a preset historical time period and the above-mentioned multi-dimensional features as a multi-dimensional feature sequence. The preset historical time period may be the combined multi-dimensional features before the current execution of the loop step. Thus, the time-series multi-dimensional data of the motor can be determined.

[0065] In the ninth step, normalize the above multi-dimensional feature sequence to obtain a normalized multi-dimensional feature sequence. Thus, data of different scales can be adjusted to the same range, facilitating the calculation of the neural network model.

[0066] In the tenth step, input the above normalized multi-dimensional feature sequence into the spatial feature extraction layer of the pre-trained motor control information generation model to obtain a feature map. Among them, the above motor control information generation model can be a neural network model that takes multi-dimensional feature data of the motor as input and control information as output. The above motor control information generation model can include a spatial feature extraction layer, a bidirectional long short-term memory network layer, a spatio-temporal attention mechanism layer, and a reinforcement learning network. The above motor control information generation model can capture complex dynamic changes during motor operation and simultaneously use the attention mechanism to focus on key time steps and features. The above spatial feature extraction layer can be used to extract spatial features in the input data, capture the mutual relationship between each sensor signal, and multiple spatio-temporal convolutional kernels (Spatial-Temporal Convolutional Kernels) can be used. Each convolutional kernel is responsible for capturing specific spatial and temporal patterns, and residual connections are adopted to prevent the problem of gradient disappearance. The above feature map can be a feature map after spatio-temporal convolution operation.

[0067] In the eleventh step, input the above feature map into the above bidirectional long short-term memory network layer to obtain a hidden state. The above bidirectional long short-term memory network layer can be used to capture long-term dependencies in time series data and understand the changing trend of the motor state. Bidirectional LSTM (Bi-LSTM) can be used, which can capture dependencies in the time series from both the forward and reverse directions simultaneously. The output of Bi-LSTM is the result of concatenating the hidden states in both directions. The above hidden state can be the hidden state after being processed by the Bi-LSTM layer.

[0068] In the twelfth step, input the above hidden state into the above spatio-temporal attention mechanism layer to obtain a weighted hidden state. The above spatio-temporal attention mechanism layer can be used to highlight important time steps and features, improving the model's attention to key information. The self-attention mechanism can be used to calculate the importance weights of each time step. Then, a weighted sum of the hidden states of each time step is performed to obtain the final weighted hidden state.

[0069] In the thirteenth step, input the above weighted hidden state into the above reinforcement learning network to obtain control information. The above reinforcement learning network can be used to optimize the control strategy to ensure smooth motor stop. The above reinforcement learning network can use a Deep Q-Network (DQN) or Policy Gradient Methods to learn the optimal control strategy. During the training process, the strategy can be continuously adjusted through interaction with the environment to enable the motor to stop smoothly. The above control information can include the voltage adjustment amount.

[0070] In the fourteenth step, control the above soft starter to reduce the motor supply voltage of the above target motor through the above control information, so that the above target motor stops smoothly. In practice, the soft starter can be controlled to reduce the motor supply voltage of the above target motor by the above voltage adjustment amount.

[0071] In the fifteenth step, in response to determining that the above target motor has not completely stopped, execute the above loop steps again. Thus, by monitoring the state of the motor, the above loop steps can be repeated and the control signal can be continuously adjusted until the motor completely stops.

[0072] The above first step to the fifteenth step are an inventive point of the embodiment of the present disclosure, which solves the technical problem of "when controlling the motor to stop, it is usually controlled based on fixed parameters or a preset simple mathematical model, and it is difficult to adapt to changing load conditions. Especially in industrial applications, the motor load may change frequently, resulting in the failure or performance degradation of traditional motor stop control strategies." The factors that cause the failure or performance degradation of the motor stop control strategy are often as follows: controlling based on fixed parameters or a preset simple mathematical model is difficult to adapt to changing load conditions. Especially in industrial applications, the motor load may change frequently. If the above factors are solved, the adaptability of the motor stop control strategy can be improved. To achieve this effect, the present disclosure combines a spatio-temporal convolutional network, a bidirectional long short-term memory network, a spatio-temporal attention mechanism, and a reinforcement learning module. It can not only effectively capture the complex dynamic changes during motor operation, but also optimize the control strategy through the attention mechanism and reinforcement learning to ensure smooth motor stop. It has higher accuracy and robustness compared to traditional methods and can be applied to various complex industrial application scenarios.

[0073] The above-described embodiments of the present disclosure have the following beneficial effects: Through the bypass switching control method of some embodiments of the present disclosure, the zero-crossing time error of the phase current caused by grid voltage interference can be reduced, thereby reducing the false triggering of over-time protection and reducing the situation where the soft starter cannot start normally. Specifically, the reason for the inability of the soft starter to start normally is that the two detection and control methods described in the background art are very susceptible to grid voltage interference and abnormal detection. When designing the soft starter, in order to avoid the thyristor from being damaged due to long-term conduction and heating, a soft start protection time is usually set, resulting in the zero-crossing time of the detected voltage or current being always greater than the soft start protection time, thus triggering start over-time protection and ultimately causing the soft starter to be unable to start normally. Based on this, in the bypass switching control method of some embodiments of the present disclosure, first, the target motor is soft-started by the soft starter corresponding to the target motor. Then, during the above soft start operation, the zero-crossing time of the current is detected as the first zero-crossing time. Thus, the zero-crossing time of the current can be detected during the soft start of the target motor. Next, the grid input voltage is sampled in real time to obtain sampling information. Thus, real-time discrete sampling of the continuously changing voltage can be performed. Secondly, according to the above sampling information, the zero-crossing time of the grid voltage is generated as the second zero-crossing time. Thus, the zero-crossing time of the grid voltage can be determined. Then, according to the above first zero-crossing time and the above second zero-crossing time, a compensated zero-crossing time is generated. Thus, the zero-crossing time of the current can be compensated by the zero-crossing time of the grid voltage, and the zero-crossing time error of the phase current caused by grid voltage interference can be reduced. Finally, according to the above compensated zero-crossing time, the bypass contactor corresponding to the target motor is controlled to operate. Thus, it is possible to avoid the zero-crossing time of the detected voltage or current being always greater than the soft start protection time and triggering start over-time protection, thereby reducing the false triggering of over-time protection, quickly switching the bypass contactor, and further reducing the situation where the soft starter cannot start normally.

[0074] Reference is made below to Figure 5 , which shows a schematic structural diagram of an electronic device 500 (such as an air-conditioning compressor) suitable for implementing some embodiments of the present disclosure. Figure 5 The electronic device shown is only an example and should not impose any limitations on the functions and usage scope of the embodiments of the present disclosure.

[0075] As Figure 5As shown, the electronic device 500 may include a processing device 501 (such as a central processing unit, a graphics processing unit, etc.), which may perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 502 or the program loaded from the storage device 508 into the random access memory (RAM) 503. In the RAM 503, various programs and data required for the operation of the electronic device 500 are also stored. The processing device 501, the ROM 502, and the RAM 503 are connected to each other through a bus 504. The input / output (I / O) interface 505 is also connected to the bus 504.

[0076] Generally, the following devices may be connected to the I / O interface 505: an input device 506 including, for example, a touch screen, a touchpad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 507 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 508 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 509. The output device 507 may further include a target motor, which may be used to provide power. The communication device 509 may allow the electronic device 500 to communicate with other devices wirelessly or wiredly to exchange data. Although Figure 5 the electronic device 500 with various devices is shown, it should be understood that it is not required to implement or have all the shown devices. Instead, more or fewer devices may be implemented or had. Figure 5 Each block shown in may represent a device or, as needed, multiple devices.

[0077] Specifically, according to some embodiments of the present disclosure, the process described above with reference to the flowchart may be implemented as a computer software program. For example, some embodiments of the present disclosure include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes program codes for performing the method shown in the flowchart. In such some embodiments, the computer program may be downloaded and installed from the network through the communication device 509, or installed from the storage device 508, or installed from the ROM 502. When the computer program is executed by the processing device 501, the above functions defined in the method of some embodiments of the present disclosure are executed.

[0078] It should be noted that the computer-readable media described in some embodiments of the present disclosure may be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In some embodiments of the present disclosure, the computer-readable storage medium may be any tangible medium that contains or stores a program, and the program can be used by or in combination with an instruction execution system, apparatus, or device. In some embodiments of the present disclosure, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The computer-readable signal medium may also be any computer-readable medium other than the computer-readable storage medium, and the computer-readable signal medium can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted by any appropriate medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0079] In some embodiments, the client and the server can communicate using any currently known or future-developed network protocol such as HTTP (HyperText Transfer Protocol), and can be interconnected with digital data communication in any form or medium (e.g., a communication network). Examples of communication networks include local area networks ("LAN"), wide area networks ("WAN"), the Internet (e.g., the Internet), and end-to-end networks (e.g., ad hoc end-to-end networks), as well as any currently known or future-developed networks.

[0080] The above computer-readable medium may be included in the above electronic device; or may exist separately without being assembled into the electronic device. The above computer-readable medium carries one or more programs, and when the above one or more programs are executed by the electronic device, the electronic device is caused to: perform a soft start operation on the target motor through the soft starter corresponding to the target motor; during the above soft start operation, detect the zero-crossing time of the current as the first zero-crossing time; perform real-time sampling on the grid input voltage to obtain sampling information; generate the zero-crossing time of the grid voltage as the second zero-crossing time according to the above sampling information; generate a compensated zero-crossing time according to the above first zero-crossing time and the above second zero-crossing time; and control the bypass contactor corresponding to the target motor to operate according to the above compensated zero-crossing time.

[0081] Computer program code for performing the operations of some embodiments of the present disclosure may be written in one or more programming languages or combinations thereof. The above programming languages include object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., by using an Internet service provider to connect through the Internet).

[0082] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code that contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system for performing the specified functions or operations, or may be implemented by a combination of dedicated hardware and computer instructions.

[0083] The functions described above in this document can be performed, at least in part, by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that can be used include: Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Application Specific Standard Products (ASSPs), Systems on a Chip (SOCs), Complex Programmable Logic Devices (CPLDs), and so on.

[0084] Some embodiments of the present disclosure also provide a computer program product, including a computer program which, when executed by a processor, implements any of the above bypass switching control methods.

[0085] The above description is only some preferred embodiments of the present disclosure and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the embodiments of the present disclosure is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above inventive concept. For example, technical solutions formed by mutually replacing the above features with technical features having similar functions (but not limited to) disclosed in the embodiments of the present disclosure.

Claims

1. A bypass switching control method, comprising: Performing a soft start operation on a target motor through a soft starter corresponding to the target motor; During the soft start operation, detecting the zero-crossing time of the current as the first zero-crossing time; Performing real-time sampling on the grid input voltage to obtain sampling information; Generating the zero-crossing time of the grid voltage as the second zero-crossing time according to the sampling information; Generating a compensated zero-crossing time according to the first zero-crossing time and the second zero-crossing time; Controlling the operation of a bypass contactor corresponding to the target motor according to the compensated zero-crossing time.

2. The method according to claim 1, wherein, The performing a soft start operation on the target motor through a soft starter corresponding to the target motor comprises: Using thyristors included in the soft starter to adjust the voltage of the target motor so that the current of the target motor rises.

3. The method according to claim 2, wherein, The method further comprises: Controlling the thyristors to stop operating in response to successful operation of the bypass contactor.

4. The method according to claim 1, wherein, The method further comprises: Controlling the bypass contactor to disconnect in response to detecting a stop operation corresponding to the target motor; Reducing the motor supply voltage of the target motor through the soft starter so that the target motor stops smoothly.

5. The method according to claim 1, wherein The performing real-time sampling on the grid input voltage to obtain sampling information comprises: Performing a step-down process on the grid input voltage to obtain a processed grid input voltage; Passing the processed grid input voltage through an analog-to-digital converter module of a control board to obtain sampled voltages as sampling information.

6. The method according to claim 1, wherein, The soft starter includes two antiparallel thyristors; And the detecting the zero-crossing time of the current as the first zero-crossing time during the soft start operation comprises: Detecting the voltages across the two thyristors; Controlling the two thyristors to turn off in response to detecting that the phase current of the circuit satisfies a preset threshold condition, wherein, in the off state, the voltage difference across each thyristor is greater than a preset threshold; Controlling the two thyristors to turn on in response to detecting that the phase current of the circuit does not satisfy the preset threshold condition, wherein, in the on state, the voltage difference across each thyristor is less than a preset voltage; Outputting a voltage pulse square wave signal based on the detected voltages; Generating the zero-crossing time of the current as the first zero-crossing time based on the voltage pulse square wave signal.

7. The method according to claim 6, wherein The generating the zero-crossing time of the current as the first zero-crossing time based on the voltage pulse square wave signal comprises: Sending the voltage pulse square wave signal to a timer module of a control board; Generating the zero-crossing time of the current as the first zero-crossing time through the timer module.

8. An electronic device, comprising: One or more processors; A target motor for providing power; A storage device having stored thereon one or more programs, When the one or more programs are executed by the one or more processors, enabling the one or more processors to implement the method according to any one of claims 1-7.

9. A computer-readable medium having a computer program stored thereon, wherein, The computer program, when executed by a processor, implements the method according to any one of claims 1-7.

10. A computer program product comprising a computer program which, when executed by a processor, implements the method according to any one of claims 1 - 7.

Images