An anti-interference synchronous acquisition and transmission system for motor angle and status signals

Abstract

The present invention discloses an anti-interference synchronous acquisition and transmission system for motor angle and status signals, which includes a signal isolation module, a parallel interface module, and a signal processing module; the signal isolation module receives the status signals related to motor control sent by the motor driver; the signal isolation module electrically isolates the status signals and then sends them to the signal processing module in parallel through the parallel interface module; the signal processing module simultaneously receives the motor angle signals collected and sent by the angle sensor, and synchronously combines the status signals and the motor angle signals and sends them to an external terminal. The direct transmission of the motor angle signals to this system can avoid their interference by the noise signals of the motor driver. The transmission of the status signals sent by the motor driver to this system through the methods of electrical isolation and parallel interface can improve their anti-interference ability and transmission accuracy. The motor angle signals and the status signals are simultaneously received and processed by this system, which can achieve synchronization in time and is beneficial for comparative analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of motor commissioning, and more specifically, to an anti-interference synchronous acquisition and transmission system for motor angle and status signals. Background Art

[0002] At present, motors are widely used in various industries. When controlling and commissioning a motor, it is necessary to be able to observe the operating state of the motor in real time (such as speed, angular position, etc.). By using an angle sensor installed on the motor shaft, the motor angle signal can be accurately and quickly acquired. The acquired motor angle signal usually needs to be compared with other motor control-related status signals (for example: the motor angle signal estimated by the motor driver) for analyzing the operating state of the motor. There are two traditional solutions for processing the motor angle signal collected by the angle sensor. One is to decode the motor angle signal collected by the angle sensor through a decoding circuit board and send it to the upper computer for observation and analysis; the other is to directly send the motor angle signal collected by the angle sensor to the motor driver. After being decoded by the motor driver, it is used as the motor angle position feedback. The motor driver can continue to combine the motor angle signal and the motor control status signal generated by itself and send it to the upper computer for analysis.

[0003] In motor control applications, developers often need to perform real-time and synchronous comparative analysis on the true angle of the motor operation (the motor angle signal collected by the angle sensor) and the motor control-related status signals generated by the motor driver (for example: the motor angle signal estimated by the motor driver). This requires that the motor angle signal acquisition and comparison solution can collect and upload the above two signals in real time, synchronously, quickly, and accurately.

[0004] The traditional solution one cannot collect the status signals sent by the motor driver. The motor driver can only separately send the status signals that need to be compared and analyzed to the host computer. This mechanism cannot ensure that the angle signals collected by the angle sensor uploaded to the host computer are synchronized with the status signals sent by the motor driver in terms of timing. Therefore, the work of accurate comparison and analysis cannot be carried out; in the traditional solution two, the angle signals collected by the angle sensor are received by the motor driver, merged with the status signals that the motor driver itself needs to compare and analyze, and then sent to the host computer for analysis. However, the motor driver is often powered by high voltage, with large input and output currents, and there are many switching devices in the circuit. Therefore, there are many electrical noises in its circuit. Whether the motor driver is receiving the motor angle signals collected by the angle sensor or sending the merged signals to the host computer, it is easily interfered by electrical noises, resulting in signal distortion and serious frame loss, and it cannot quickly and completely carry out signal comparison and analysis. Especially in the motor driver circuit with "hot ground design" (the control ground wire and the power ground wire are the same ground wire), since the signals sent by the angle sensor are generally analog signals or digital signals with very fast frequencies, this noise interference phenomenon is inevitable. Moreover, when the motor driver with hot ground design receives the motor angle signals collected by the angle sensor, it cannot be directly electrically connected and must add an electrical isolation circuit (opto-isolation, magnetic isolation circuit), increasing the cost.

[0005] Therefore, how to achieve the fast acquisition and upload of motor angle sensor signals, how to synchronize with the status signals that need to be compared sent by the motor driver, and how to improve the anti-interference ability of signal acquisition and transmission are all problems that need to be urgently solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides an anti-interference synchronous acquisition and transmission system for motor angle and status signals, including a signal isolation module, a parallel interface module, and a signal processing module; the signal isolation module receives the status signals related to motor control sent by the motor driver; the signal isolation module electrically isolates the status signals and then sends them to the signal processing module in parallel through the parallel interface module; the signal processing module simultaneously receives the motor angle signals collected and sent by the angle sensor, and synchronously merges the status signals and the motor angle signals and sends them to an external terminal. The motor angle signals collected by the angle sensor are directly transmitted to the signal processing module of the system, which can avoid being interfered by the noise signals of the motor driver; the status signals generated by the motor driver are transmitted to the signal processing module of the system through the methods of electrical isolation and parallel interface, which can improve its anti-interference ability and transmission speed, and increase the accuracy of signal transmission. The motor angle signals and the status signals are received and processed by the system at the same time and transmitted to the signal processing module at the same time. Therefore, the signal processing module can synchronize and merge the above two signals in terms of timing and send them to the host computer, facilitating signal comparison and analysis.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] An anti-interference synchronous acquisition and transmission system for motor angle and status signals, comprising a signal isolation module, a parallel interface module and a signal processing module; the signal isolation module receives status signals related to motor control sent by a motor driver; the signal isolation module electrically isolates the status signals and then sends them in parallel to the signal processing module through the parallel interface module; the signal processing module simultaneously receives the motor angle signals collected and sent by an angle sensor, and synchronously combines the status signals and the motor angle signals and sends them to an external terminal.

[0009] Preferably, the external terminal is a host computer, and the host computer receives the status signals and the motor angle signals after synchronous combination and performs analysis and comparison.

[0010] Preferably, the motor driver sends the status signals in parallel, and the motor driver is electrically connected to a high-power power system.

[0011] Preferably, the signal processing module decodes the motor angle signals to obtain decoded angle signals, performs debounce processing on the status signals to obtain debounced status signals, and synchronizes and combines the decoded angle signals and the debounced status signals and sends them to the host computer.

[0012] Preferably, the specific steps of the debounce processing are as follows:

[0013] Step 21: Sample the parallel data output by the parallel interface module;

[0014] Step 22: Determine whether the parallel data sampled in the current sampling period is equal to the currently updated parallel data; if so, clear the debounce count register, and make the currently cached parallel data equal to the currently updated parallel data again, and exit the debounce processing of the current sampling period; otherwise, enter Step 23;

[0015] Step 23: Determine whether the parallel data sampled in the current sampling period is equal to the currently cached parallel data; if not, update the currently cached parallel data, make the currently cached parallel data equal to the parallel data sampled in the current sampling period, and clear the debounce count register, and exit the debounce processing of the current sampling period; otherwise, enter Step 24;

[0016] Step 24: Increment the count value of the debounce count register by 1;

[0017] Step 25: Determine whether the count value is greater than a set threshold. If not, exit the debounce processing for the current sampling period; otherwise, proceed to Step 26;

[0018] Step 26: Update the currently updated parallel data, making the currently updated parallel data equal to the currently cached parallel data, and clear the debounce count register to complete the debounce processing for the current sampling period.

[0019] As can be seen from the above technical solutions, compared with the prior art, the present invention discloses and provides an anti-interference synchronous acquisition and transmission system for motor angle and status signals. The motor angle signal collected by the angle sensor is directly transmitted to the signal processing module without passing through the motor driver for processing, avoiding interference of the motor angle signal by the noise signal of the motor driver. The system of the present invention is powered by a separate externally connected 15V DC power supply, which is converted into a weak power supply such as 5V or 3.3V on the circuit board of the system. In order to increase the anti-interference ability of the present invention system to receive the status signal sent by the motor driver and avoid the signal sent from interfering with the weak power supply system connected to the present invention system, the present invention adopts a parallel interface module and a signal isolation module to implement a signal transmission mechanism of parallel transmission and electrical isolation. Parallel transmission enables more effective signal data bits to be transmitted per unit time, thereby reducing the signal change rate and increasing the anti-interference ability of the signal. Electrical isolation completely isolates the strong power supply system connected to the motor driver from the weak power supply connected to the present invention system, avoiding signal interference caused by the noise of the motor driver to the present invention system. At the same time, the signal processing module performs debounce processing on the status signal sent by the motor driver to ensure the correctness of the signal data, and parallel transmission slows down the signal change rate, thereby ensuring sufficient time for debounce processing of the signal. Therefore, the present invention uses a signal isolation module, a parallel interface module, and a signal processing module to transmit and process the motor angle signal collected by the angle sensor and the status signal sent by the motor driver, improving the speed and reliability of signal transmission during the motor test, and making the signals synchronized in time, which is beneficial for signal comparison and analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for description in the embodiments or the prior art. Obviously, the drawings described below are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0021] Figure 1 The drawings are schematic diagrams of the signal transmission path of the synchronous acquisition and transmission system for motor angle and status signals provided by the present invention;

[0022] Figure 2 The accompanying drawing is a general schematic diagram of the signal acquisition and transmission system provided by the present invention;

[0023] Figure 3 The accompanying drawing is a signal processing and transmission schematic diagram of the signal processing module provided by the present invention;

[0024] Figure 4 The accompanying drawing is a flowchart of the debounce processing of the signal processing module provided by the present invention;

[0025] Figure 5 The accompanying drawing is a comparison result diagram of the embodiments provided by the present invention. Detailed implementation manners

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] An embodiment of the present invention discloses an anti-interference synchronous acquisition and transmission system for motor angle and status signals, including a signal isolation module, a parallel interface module, and a signal processing module; the signal isolation module receives status signals related to motor control sent by a motor driver; the signal isolation module electrically isolates the status signals and then sends them in parallel to the signal processing module through the parallel interface module; the signal processing module simultaneously receives the motor angle signals collected and sent by an angle sensor, and synchronously combines the status signals and the motor angle signals and sends them to an external terminal.

[0028] To further optimize the above technical solution, the external terminal is a host computer, and the host computer receives the synchronously combined status signals and motor angle signals sent by the signal processing module and performs analysis and comparison.

[0029] To further optimize the above technical solution, the motor driver sends status signals in parallel and is electrically connected to a 380V three-phase power supply or a single-phase 220V power supply, etc. The power supply connected to the motor driver is strong electricity, and its noise signal will be relatively serious, and the interference to the data signal is relatively large. The anti-interference effect of the signal acquisition and transmission of the present invention is better.

[0030] To further optimize the above technical solution, the signal processing module decodes the motor angle signals to obtain the decoded angle signals, performs debounce processing on the status signals to obtain the debounced status signals, and synchronizes and combines the decoded angle signals and the debounced status signals and sends them to the host computer.

[0031] To further optimize the above technical solution, the status signal can be an estimated motor angle signal estimated by the motor driver through an algorithm.

[0032] To further optimize the above technical solution, the specific steps of the debounce processing are as follows:

[0033] S21: Sample the parallel data output by the parallel interface module; the data signals on the parallel interface module are represented by the high and low levels of each signal bit terminal on the parallel interface (high level represents 1, low level represents 0). The signal processing module samples these high and low level signals at a relatively fast sampling frequency to determine whether they are high level or low level signals, and then forms the parallel data sampled in the current sampling period according to the high and low level combinations of all signal bits;

[0034] S22: Determine whether the parallel data sampled in the current sampling period is equal to the currently updated parallel data; if so, clear the debounce count register, and make the currently cached parallel data equal to the currently updated parallel data, and exit the debounce processing of the current sampling period; otherwise, enter S23;

[0035] S23: Determine whether the parallel data sampled in the current sampling period is equal to the currently cached parallel data. If they are not equal, update the currently cached parallel data, make the currently cached parallel data equal to the parallel data sampled in the current sampling period, and clear the debounce count register, and exit the debounce processing of the current sampling period; otherwise, enter S24;

[0036] S24: Increment the count value of the debounce count register by 1;

[0037] S25: Determine whether the count value is greater than the set threshold. If not, exit the debounce processing of the current sampling period; otherwise, enter S26;

[0038] S26: Update the currently updated parallel data, make the currently updated parallel data equal to the currently cached parallel data, and clear the debounce count register to complete the debounce processing of the current sampling period.

[0039] To further optimize the above technical solution, the sampling period is equal to the control period of the signal processing module. Each control period refers to the execution period of the core program of the signal processing module. Within one execution period, the signal processing module will complete tasks such as signal sampling, signal decoding, signal merging, and synchronous transmission.

[0040] Embodiment

[0041] Such as Figure 1The signal transmission path of the present invention is shown. In each control cycle, the system of the present invention simultaneously receives the angle signal collected by the angle sensor and the status signal related to motor control that the motor driver needs to send. Both of these signals are transmitted to the signal processing module of the device for data processing.

[0042] After the status signal sent by the motor driver is electrically isolated by the signal isolation module, it is sent to the signal processing module through the parallel communication method of the parallel interface module.

[0043] As Figure 2 The general circuit schematic diagram of this embodiment is shown. The signal processing module is mainly composed of a CPU, a resolver decoding chip, and some peripheral circuits. The CPU selects the DSP processor U1 with the model number TMS320F28335. The motor angle sensor selects a resolver (abbreviation: resolver), and the corresponding resolver decoding chip selects the chip U2 with the model number AD2S1210. It forms a resolver signal excitation and decoding circuit with some peripheral devices. A pair of excitation signals (EXC+, EXC-) generated by the excitation circuit are sent to the resolver through the connector J2. The angle information of the resolver rotor (the rotor is fixed on the motor shaft) acts on the excitation signal to generate two pairs of resolver angle feedback signals (COS+, COS- and SIN+, SIN-). The feedback signals are sent to the resolver decoding chip through the connector J2 for signal decoding. The decoded signal is the decoded motor angle signal. The data is transmitted through the SPI interface between the resolver decoding chip and the CPU, and the decoded motor angle signal is transmitted to the CPU of the signal processing module.

[0044] The signal isolation module is mainly composed of a signal isolation chip and some peripheral circuits. The status signal sent by the motor driver is transmitted to the signal isolation module through the connector J1. The isolation chips of the signal isolation module select the magnetic coupling isolation chips U3, U4, U5, and U6 with the model number ADUM1400. The signal isolation module enables the status signal sent by the motor driver to be transmitted to the signal processing module after electrical isolation.

[0045] The parallel interface module is mainly composed of the parallel interfaces of the CPU and the magnetic coupling isolation chip respectively, and the connection circuit between the interfaces. Compared with the serial communication circuit, it can transmit the status signal sent by the motor driver to the signal processing module more quickly and accurately, which is convenient for the signal processing module to perform debounce processing on the signal.

[0046] After the signal processing module synchronously combines and processes the motor angle signal and the status signal sent by the motor driver, it is sent to the host computer through the connector J3 in the form of a CAN bus.

[0047] The signal processing module is the central control unit of the entire system. The processing steps of the signal within this unit are as Figure 3 shown:

[0048] S1: Within the same execution cycle, the signal processing module first decodes the angle signal collected by the angle sensor;

[0049] S2: At the same time, the signal processing module performs "debouncing" on the status signal sent by the motor driver, thereby eliminating the glitches and noise on the status signal sent by the motor driver, ensuring that the status signal data sent by the motor driver is accurately updated;

[0050] S3: After obtaining the above two accurate signals, the signal processing module synchronously combines the two signals in terms of timing and sends them to the host computer for comparative analysis.

[0051] The method steps for the signal processing module to perform "debouncing" on the signal in software are as Figure 4 shown:

[0052] S21: Sample the parallel data output by the parallel interface module;

[0053] S22: Determine whether the parallel data NewSampleData sampled in the current sampling period is equal to the currently updated parallel data AcceptedData, where the currently updated parallel data refers to the accurate parallel data after debouncing processing; if so, clear the debounce count register, where the main function of the debounce count register is to count the number of consecutive cycles of the changed parallel data in the subsequent sampling when the parallel data NewSampleData sampled in the current sampling period changes compared with the previous sampling period, and make the currently cached parallel data BufferData equal to the currently updated parallel data AcceptedData again, and exit the debounce processing of the current sampling period. The main purpose of BufferData is to store the changed parallel data when the parallel data sampled in the current sampling period changes compared with the previous sampling period; otherwise, enter S23;

[0054] S23: Determine whether the parallel data sampled in the current sampling period is equal to the currently cached parallel data. If not, it means a new data appears, then update the currently cached parallel data, make the currently cached parallel data equal to the parallel data sampled in the current sampling period, clear the debounce count register, and re-count the number of sampling periods for the continuous appearance of the new data, and exit the debounce processing of the current sampling period; otherwise, enter S24;

[0055] S24: Increment the count value of the debounce count register by 1;

[0056] S25: Determine whether the count value is greater than the set threshold. If not, exit the debounce processing for the current sampling period; otherwise, if it is greater than the set threshold, indicating that a new valid parallel data has occurred, then proceed to S26;

[0057] S26: Update the currently updated parallel data AcceptedData to obtain the new accurately debounced data. Let the currently updated parallel data AcceptedData be equal to the currently buffered parallel data BufferData. At this time, the currently buffered parallel data BufferData is an accurately debounced parallel data, and clear the debounce count register to prepare for receiving the next new parallel data, successfully completing the debounce processing for the current sampling period.

[0058] As Figure 5 shown is an example of the actual test results of the present invention, which is an angle comparison analysis diagram of the motor operating state drawn by the host computer. The abscissa in the figure represents the number of received signal data (10,000 data are received per second), and the ordinate represents the position angle of the motor (for example: 180°). The solid line represents the motor angle signal collected by the angle sensor, and the dashed line represents the estimated motor angle signal sent by the motor driver. It can be seen that even when communicating with a motor driver designed with a hot ground and high-voltage power supply, the motor angle and status signal synchronous acquisition and transmission system of the present invention can still synchronously, quickly, and accurately send the estimated motor angle signal of the motor driver and the real motor angle signal collected by the angle sensor (resolver) to the host computer.

[0059] Advantages of the present invention:

[0060] 1) In the field of motor control, through the system of the present invention, the real motor angle signal sent by the angle sensor and other state signals related to motor control that need to be compared and analyzed sent by the motor driver (for example: the estimated motor angle signal of the motor driver) can be sampled, and these two signals can be synchronized in time sequence and merged and sent to the host computer. The present invention can more conveniently synchronously integrate the angle signal collected by the angle sensor and the signals sent by other devices that need to be compared and analyzed, making the signals to be compared synchronous in time sequence, which is crucial when analyzing these signals.

[0061] 2) In terms of electricity, the present invention is independent of the motor driver and is connected to a weak current system. The angle signal collected by the angle sensor "bypasses" the motor driver and is uploaded to the host computer through the present invention. Therefore, fundamentally, the angle signal collected by the angle sensor is avoided from being interfered by the electrical noise of the motor driver. Since the present invention also adopts some methods for eliminating signal interference (adding a signal isolation module and a parallel interface module, and performing debounce processing on the signal in the signal processing module), when communicating with the motor driver, especially when communicating with the motor driver designed with "hot ground", the advantages are obvious. Compared with other solutions, it can collect the status signal sent by the motor driver at high speed and accurately. Therefore, whether collecting the angle signal of the angle sensor or the status signal sent by other devices such as the motor driver, the interference of the noise signal can be eliminated, so that the collected signal is accurate and can be uploaded quickly, which is convenient for signal analysis.

[0062] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For the relevant parts, refer to the description in the method part.

[0063] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An anti-interference synchronous acquisition and transmission system for motor angle and status signals, characterized in that, Including: A signal isolation module, a parallel interface module, and a signal processing module; The signal isolation module receives the status signal sent by the motor driver; the signal isolation module electrically isolates the status signal and then sends it in parallel to the signal processing module through the parallel interface module; the signal processing module simultaneously receives the motor angle signal collected and sent by the angle sensor, and synchronously combines the status signal and the motor angle signal and sends them to an external terminal; The system is powered by a single externally connected DC power supply, and the DC power supply is converted into a low-voltage power supply in the system; The signal processing module decodes the motor angle signal to obtain a decoded angle signal, and performs debounce processing on the status signal to obtain a debounced status signal; the specific steps of the debounce processing are as follows: Step 21: Sample the parallel data output by the parallel interface module; Step 22: Determine whether the parallel data sampled in the current sampling period is equal to the currently updated parallel data; If so, clear the debounce count register, and make the currently cached parallel data equal to the currently updated parallel data again, and exit the debounce processing of the current sampling period; Otherwise, go to step 23; Step 23: Determine whether the parallel data sampled in the current sampling period is equal to the currently cached parallel data. If they are not equal, update the currently cached parallel data, make the currently cached parallel data equal to the parallel data sampled in the current sampling period, and clear the debounce count register, and exit the debounce processing of the current sampling period; Otherwise, go to step 24; Step 24: Increment the count value of the debounce count register by 1; Step 25: Determine whether the count value is greater than the set threshold. If not, exit the debounce processing of the current sampling period; Otherwise, go to step 26; Step 26: Update the currently updated parallel data, make the currently updated parallel data equal to the currently cached parallel data, and clear the debounce count register to complete the debounce processing of the current sampling period.

2. The anti-interference motor angle and status signal synchronous acquisition and transmission system according to claim 1, characterized in that, The external terminal is a host computer, and the host computer receives the status signal and the motor angle signal after synchronous combination and performs analysis and comparison.

3. An anti-interference synchronous acquisition and transmission system for motor angle and status signals according to claim 1, characterized in that, The motor driver sends the status signal in parallel, and the motor driver is electrically connected to the high-voltage power supply system.

4. An anti-interference synchronous acquisition and transmission system for motor angle and status signals according to claim 2, characterized in that Synchronize and combine the decoded angle signal and the debounced status signal, and send them to the host computer.

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