Method for processing phase detection signal of resolver conversion system, chip and system

Abstract

The application provides a method for processing a phase detection signal of a resolver conversion system, a chip and a system. The method comprises: obtaining a first phase detection signal component and a second phase detection signal component; the first phase detection signal component is the same frequency and the same phase as an excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency; the first phase detection signal component and the second phase detection signal component are respectively synchronized with a sine signal and a cosine signal based on a preset amplitude ratio to obtain a first phase detection output signal and a second phase detection output signal; and the preset amplitude ratio is configured to at least partially offset a second harmonic component generated by the first phase detection signal component and a second harmonic component generated by the second phase detection signal component in the phase detection output signal. The application considers the tracking response speed while ensuring the conversion accuracy, and effectively alleviates the technical contradiction between the accuracy and the conversion speed in the existing resolver conversion system.

Description

Technical Field

[0001] This invention relates to the field of synchronous phase detection technology, and specifically to a phase detection signal processing method, chip, and system for a rotary transformer conversion system. Background Technology

[0002] Rotary transformers are widely used in servo motors, aerospace, industrial robots, electric vehicle drive systems, and other fields requiring high-precision angle measurement in harsh environments. The sine and cosine signals output by the rotary transformer, modulated by the excitation frequency, need to be converted into angle values ​​by a rotary transformer conversion system for use by subsequent control systems. Existing rotary transformer conversion systems generally employ synchronous phase detection technology. This involves multiplying the sine and cosine signals output by the rotary transformer using a reference signal that is in phase and frequency with the excitation signal, obtaining a phase-detected output signal containing DC and harmonic components of angle information. This signal is then filtered to extract the DC component for closed-loop tracking and conversion. Building upon this, many systems further employ Type II tracking loops to achieve dynamic angle tracking and decoding.

[0003] However, in existing synchronous phase detection schemes, the phase detection output signal inevitably generates a second harmonic component in addition to the DC component. This second harmonic component will reduce the system's angle conversion accuracy; adding a filtering stage to suppress harmonics during the processing of the Type II tracking loop will introduce phase lag, affecting the tracking response speed.

[0004] Therefore, there is an urgent need to provide a phase detection signal processing method, chip, and system for a rotary transformer conversion system, which can actively control the generation of second harmonic components and improve conversion accuracy and tracking response speed. Summary of the Invention

[0005] In view of this, it is necessary to provide a method for generating and processing phase detection signals in a rotary transformer conversion system to solve the technical problem of difficulty in balancing conversion accuracy and tracking response speed in the prior art.

[0006] To address the aforementioned technical problems, in a first aspect, the present invention provides a phase detection signal processing method for a rotary transformer conversion system, used for synchronously phase detecting the sinusoidal and cosine signals output by the rotary transformer after excitation frequency modulation, comprising: Acquire a first phase detection signal component and a second phase detection signal component; the first phase detection signal component is in phase and frequency with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency; Based on a preset amplitude ratio, the first phase detection signal component and the second phase detection signal component are synchronously phase-detected with the sine signal and the cosine signal, respectively, to obtain the first phase detection output signal and the second phase detection output signal; the first phase detection output signal and the second phase detection output signal include a DC component related to the rotation angle of the rotary transformer; The preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out.

[0007] In one possible implementation, the step of synchronously phase-detecting the first phase-detection signal component and the second phase-detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, to obtain the corresponding first phase-detection output signal and second phase-detection output signal, includes: The first phase detection signal component and the second phase detection signal component are superimposed at the preset amplitude ratio to obtain a composite phase detection signal; The composite phase detection signal is multiplied by the sine signal and the cosine signal respectively for synchronous phase detection, thereby obtaining the first phase detection output signal and the second phase detection output signal.

[0008] In one possible implementation, the step of synchronously phase-detecting the first phase-detection signal component and the second phase-detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, to obtain the corresponding first phase-detection output signal and second phase-detection output signal, includes: The first phase detection signal component is multiplied by the sine signal and the cosine signal respectively to obtain the first mixing signal and the second mixing signal. The second phase detection signal component is multiplied by the sine signal and the cosine signal respectively to obtain the third mixing signal and the fourth mixing signal. The first mixing signal and the third mixing signal are superimposed with the preset amplitude ratio to obtain the first phase detection output signal, and the second mixing signal and the fourth mixing signal are superimposed with the preset amplitude ratio to obtain the second phase detection output signal.

[0009] In one possible implementation, the first phase detection signal component and the second phase detection signal component have the same signal type.

[0010] In one possible implementation, when the first phase detection signal component is a sine wave signal, the preset amplitude ratio is 1.

[0011] In one possible implementation, when the first phase detection signal component is a square wave signal, the amplitude of the second phase detection signal component is 2 / 3 of the amplitude of the first phase detection signal component.

[0012] In one possible implementation, when the first phase detection signal component is a square wave signal, the amplitude of the second phase detection signal component is 5 / 8 of the amplitude of the first phase detection signal component.

[0013] One possible implementation also includes: The first phase detection output signal and the second phase detection output signal are filtered by a notch filter to obtain a first optimized output signal and a second optimized output signal. The center frequency of the notch filter is configured to be four times the excitation frequency.

[0014] Secondly, the present invention also provides a resolver decoding chip, comprising: The signal input interface is used to receive the sinusoidal and cosine signals modulated by the excitation frequency from the rotary transformer. A phase detection signal generation circuit is used to generate a first phase detection signal component and a second phase detection signal component; the frequency of the first phase detection signal component is in phase with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency; A synchronous phase detection circuit, connected to the phase detection signal generation circuit, is used to synchronously phase-detect the first phase detection signal component and the second phase detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, thereby obtaining a first phase detection output signal and a second phase detection output signal; wherein, the preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out; An angle generation circuit, connected to the synchronous phase detection circuit, is used to generate the angle value of the resolver decoder based on the first phase detection output signal and the second phase detection output signal. The signal output interface is used to output the angle value to an external device or an internal control chip.

[0015] Thirdly, the present invention also provides a rotary transformer conversion system, comprising: a rotary transformer decoding chip and a peripheral chip; The resolver decoding chip is the resolver decoding chip described in the above possible implementations; The peripheral chip is connected to the resolver decoding chip and is used to receive the angle value generated by the resolver decoding chip.

[0016] The beneficial effects of this invention are as follows: The phase detection signal processing method for the rotary transformer conversion system provided by this invention acquires a first phase detection signal component with the same frequency and phase as the excitation frequency and a second phase detection signal component with a frequency three times the excitation frequency. Based on a preset amplitude ratio, these two components are synchronously phase-detected with the sine and cosine signals output by the rotary transformer, respectively. This ensures that the second harmonic component generated by the first phase detection signal component and the second phase detection signal component in the phase detection output signal at least partially cancel each other out. Compared to the passive processing method in the prior art, which generates the second harmonic first and then filters it out, this invention preprocesses the second harmonic during the generation of the phase detection output signal, eliminating or significantly reducing the second harmonic in the phase detection output signal. This allows the Type II tracking loop to maintain conversion accuracy while also considering tracking response speed, effectively alleviating the technical contradiction between accuracy and conversion speed in existing rotary transformer conversion systems. Furthermore, this invention only requires acquiring the second phase detection signal component and adding it to the synchronous phase detection process in the prior art to achieve the above objectives. It is effectively compatible with existing technologies and easy to integrate into chips. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic flowchart of an embodiment of the phase detection signal processing method for the rotary transformer conversion system provided by the present invention; Figure 2 A schematic flowchart of an embodiment of the present invention, which obtains the first phase detection output signal and the second phase detection output signal by superposition followed by phase detection; Figure 3 A schematic flowchart of an embodiment of the present invention, which obtains the first phase detection output signal and the second phase detection output signal by means of first phase detection and then superposition; Figure 4 This invention provides a schematic diagram of an embodiment of a periodic square wave signal corresponding to a first phase detection signal component, a second phase detection signal component, and a composite phase detection signal. Figure 5 The frequency-phase diagram of the notch filter provided by this invention; Figure 6 This is a schematic diagram of an embodiment of the rotary transformer conversion system provided by the present invention; Figure 7This is a schematic diagram of an embodiment of the resolver decoding chip provided by the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] It should be understood that the illustrative drawings are not drawn to scale. The flowcharts used in this invention illustrate operations implemented according to some embodiments of the invention. It should be understood that the operations in the flowcharts may be implemented out of order, and steps without logical contextual relationships may be reversed or performed simultaneously. Furthermore, those skilled in the art, guided by the content of this invention, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] This invention provides a phase detection signal processing method, chip, and system for a rotary transformer conversion system, which are described below.

[0023] Figure 1 This is a schematic flowchart of an embodiment of the phase detection signal processing method for a resolver conversion system provided by the present invention, used to synchronously detect the phase of the sinusoidal and cosine signals modulated by the excitation frequency output of the resolver. Figure 1 As shown, the phase detection signal processing method for the rotary transformer conversion system includes: S101. Obtain the first phase detection signal component and the second phase detection signal component; the first phase detection signal component is in phase and frequency with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency.

[0024] S102. Based on a preset amplitude ratio, the first phase detection signal component and the second phase detection signal component are synchronously phase-detected with the sine signal and the cosine signal, respectively, to obtain the first phase detection output signal and the second phase detection output signal; the first phase detection output signal and the second phase detection output signal include a DC component related to the rotation angle of the rotary transformer.

[0025] The preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out.

[0026] Compared with existing technologies, the phase detection signal processing method for a resolver conversion system provided in this invention acquires a first phase detection signal component that is in phase with the excitation frequency and a second phase detection signal component with a frequency three times the excitation frequency. Based on a preset amplitude ratio, these two components are synchronously phase-detected with the sine and cosine signals output by the resolver, respectively. This ensures that the second harmonic component generated by the first phase detection signal component and the second phase detection signal component in the phase detection output signal at least partially cancel each other out. Compared to the passive processing method in existing technologies that first generates the second harmonic and then filters it out, this invention preprocesses the second harmonic during the generation of the phase detection output signal, eliminating or significantly reducing the second harmonic in the phase detection output signal. This allows the Type II tracking loop to maintain conversion accuracy while ensuring tracking response speed, effectively alleviating the technical contradiction between accuracy and conversion speed in existing resolver conversion systems. Furthermore, this invention only requires acquiring the second phase detection signal component and adding it to the synchronous phase detection process in existing technologies to achieve the above objectives, effectively ensuring compatibility with existing technologies and facilitating chip integration.

[0027] As can be seen from the above description, the purpose of the embodiments of the present invention is to suppress the second harmonic component in the first phase detection output signal and the second phase detection output signal, which can be achieved in the following two equivalent ways: the first is to first superimpose the first phase detection signal component and the second phase detection signal component, and then use the superimposed phase detection signal to synchronously detect the sine signal and the cosine signal respectively, that is, the superposition followed by phase detection method; the second is to use the first phase detection signal component and the second phase detection signal component to synchronously detect the sine signal and the cosine signal respectively, and then superimpose the obtained signals, that is, the phase detection followed by superposition method.

[0028] In specific embodiments of the present invention, such as Figure 2 As shown, step S102 includes: S201. The first phase detection signal component and the second phase detection signal component are superimposed with a preset amplitude ratio to obtain a composite phase detection signal. S202. Multiply the composite phase detection signal with the sine signal and the cosine signal respectively to perform synchronous phase detection, and obtain the first phase detection output signal and the second phase detection output signal accordingly.

[0029] In specific embodiments of the present invention, such as Figure 3 As shown, step S102 further includes: S301. Multiply the first phase detection signal component with the sine signal and the cosine signal respectively to obtain the first mixing signal and the second mixing signal. S302. Multiply the second phase detection signal component with the sine signal and the cosine signal respectively to obtain the third mixing signal and the fourth mixing signal. S303. The first mixing signal and the third mixing signal are superimposed with a preset amplitude ratio to obtain the first phase detection output signal, and the second mixing signal and the fourth mixing signal are superimposed with a preset amplitude ratio to obtain the second phase detection output signal.

[0030] The embodiments of the present invention provide two equivalent methods for obtaining the first phase detection output signal and the second phase detection output signal: superposition followed by phase detection and phase detection followed by superposition. This improves the diversity of methods and provides options for engineering applications.

[0031] To achieve second harmonic cancellation, in a specific embodiment of the present invention, the first phase detection signal component and the second phase detection signal component have the same signal type.

[0032] Specifically, the first phase detection signal component and the second phase detection signal component can be sine waves or square waves.

[0033] Because of its pure spectrum and simple harmonic components, sine wave signals are widely used in aerospace, military fire control, and high-precision inertial navigation applications where extremely high conversion accuracy is required. Square wave signals can be directly generated using comparators or simple digital logic circuits, eliminating the need for complex sine wave oscillators or digital-to-analog converters. This results in low cost, simple circuit structure, and applicability to analog chips and systems with high anti-interference requirements.

[0034] In addition, in digital processors, square wave and triple-frequency square wave signals can be combined with the timing of clock signals to generate +1 / -1 periodic signals. Synchronous phase detection of sine and cosine signals modulated by excitation frequency can be performed through + / - sign gating, combined with their respective amplitude ratios. The operation is simple and suitable for digital chips and systems.

[0035] When the first phase detection signal component is a sine wave signal, the specific process for determining the preset amplitude ratio is as follows: The sine signal is represented by S12, the cosine signal by C12, and the excitation frequency is... The angle of the rotary transformer is The first phase detection signal component is The second phase detection signal component is If implemented by first superimposing and then detecting the phase, the composite phase detection signal is: Based on this composite phase detection signal, the first phase detection output signal is: (1) If synchronous phase detection is performed using only the first phase detection signal component according to the existing technology, the first phase detection output signal is: (2) Comparing equations (1) and (2), it can be seen that: based on the composite phase detection signal after the superposition of the first phase detection signal component and the second phase detection signal component, the low harmonic frequency shifts from the 2nd to the 4th, and the amplitudes of the two are the same. Therefore, when the first phase detection signal component is a sine wave signal, the preset amplitude ratio is 1.

[0036] It should be noted that the lowest harmonic frequency is the main factor affecting the system's accuracy and bandwidth. Increasing the lowest harmonic frequency can widen the system bandwidth, enhance the system's tracking performance, and increase the system gain, which is beneficial for improving accuracy.

[0037] It should be understood that the process of the second phase detection output signal is the same as that of the first phase detection output signal, and will not be repeated here.

[0038] When the first phase detection signal component is a square wave signal, the specific process for determining the preset amplitude ratio is as follows: The sinusoidal signal modulated by the excitation frequency is represented as S12, and the cosine signal is represented as C12. The excitation frequency is... The angle of the rotary transformer is The Fourier series of the second phase detection signal component is: If the first two terms of the second phase detection signal component are taken and superimposed sequentially, then the second phase detection signal component is: Based on this, the third mixing signal is: (3) In equation (3), the third mixing signal consists of the second and fourth harmonics and higher-order harmonics, but does not include the DC component.

[0039] The first phase detection signal component corresponding to the square wave signal is If the first two terms of the first phase detection signal component are taken and used for synchronous phase detection, the first mixing signal is: (4) Comparing equations (3) and (4), it can be seen that the coefficient of the second harmonic in the first mixing signal is -1 / 3, and the coefficient of the second harmonic in the third mixing signal is 1 / 2. In order to completely eliminate the second harmonic component, in the specific embodiment of the present invention, the amplitude of the second phase detection signal component is 2 / 3 of the amplitude of the first phase detection signal component.

[0040] Multiplying the amplitude of equation (3) by 2 / 3 and then superimposing it with equation (4), ignoring harmonics of order 4 and above, we get: (5) Comparing Equation (5) and Equation (4), the second harmonic in Equation (5) is completely canceled out, and the lowest harmonic shifts to the fourth harmonic.

[0041] In practical engineering applications, the fourth harmonic should not be too high, otherwise it will increase the design burden of subsequent filters and may affect the overall accuracy of the system.

[0042] As can be seen from equation (3), the coefficient of the fourth harmonic in the third mixing signal is -1 / 2.

[0043] The first mixing signal determination process requires additional input. This is because: the fifth harmonic component of a square wave With input signal Multiplication, product to sum That is, the difference between the 5th harmonic and the 1st input signal produces the 4th harmonic, with a coefficient of 1 / 10. Adding this to the coefficient of the 4th harmonic in equation (4), we can get the overall coefficient of the 4th harmonic as 1 / 10 - 1 / 6 = -1 / 15.

[0044] If synchronous phase detection is performed with the amplitude of the second phase detection signal component being 2 / 3 of the amplitude of the first phase detection signal component, the second harmonic is indeed completely canceled out. However, the coefficient of the fourth harmonic is: (6) That is: the amplitude of the fourth harmonic is from Increased to It was magnified 6 times.

[0045] In order to suppress the second harmonic while taking into account the amplification of the fourth harmonic, in a preferred embodiment of the present invention, when the first phase detection signal component is a square wave signal, the amplitude of the second phase detection signal component is 2 / 3 of the amplitude of the first phase detection signal component.

[0046] At this point, the coefficient of the 4th harmonic is: (7) Second harmonic coefficient:

[0047] As can be seen from the above description, although the second harmonic is not completely eliminated, its harmonic coefficient is very small and can be ignored. Based on this, the fourth harmonic is suppressed to a certain extent.

[0048] Furthermore, the calculation of 2 / 3 cannot be achieved using simple bit shifting; a multiplier must be used, consuming computational resources. In binary, division by 2 and division by 8 can be achieved through a right shift operation, eliminating the need for a multiplier and reducing resource consumption.

[0049] It should be noted that in practical engineering, the preset amplitude ratio of 2 / 3 for completely eliminating the second harmonic can be reduced to a smaller value, such as 1 / 2, depending on the requirements. Both can achieve the technical effect of partially eliminating the second harmonic to a considerable extent, while minimizing resource consumption.

[0050] In the above embodiments, the synchronous phase detection method based on square wave signals is to perform phase detection first and then superposition. In practical applications, it can also be achieved by superposition first and then phase detection, that is, superimposing the first phase detection signal component and the second phase detection signal component, which are square wave signals, to obtain a composite phase detection signal before performing synchronous phase detection. Specifically, one periodic waveform of the first phase detection signal component, the second phase detection signal component, and the composite phase detection signal is as follows: Figure 4 As shown, Figure 4 The square wave in the signal is the first phase detection signal component, and the third harmonic square wave is the second phase detection signal component. When they are superimposed, they form the composite phase detection signal.

[0051] As can be seen from the description of the above embodiments: after synchronous phase detection of the sine and cosine signals based on the first and second phase detection signal components, the amplitude of the fourth harmonic component will increase. To further suppress the fourth harmonic component, in some embodiments of the present invention, after step S102, the following is further included: The first phase detection output signal and the second phase detection output signal are filtered by a notch filter to obtain the first optimized output signal and the second optimized output signal. The center frequency of the notch filter is configured to be four times the excitation frequency.

[0052] Specifically, the transfer function formula for a second-order notch filter is expressed as:

[0053] in, Indicates the center frequency of the notch filter. , Indicates the attenuation coefficient. This represents the Laplace transform factor.

[0054] In a specific embodiment of the present invention, the excitation frequency is 10kHz, and the center frequency of the notch filter is... =40kHz. Center frequency attenuation 1 / 10 (-20 dB), bandwidth at center frequency 5kHz, its amplitude and phase as a function of frequency curves are as follows. Figure 5 As shown.

[0055] This invention, through cascading a notch filter with a center frequency four times the excitation frequency after the phase detection output signal, utilizes the narrowband frequency-selective attenuation characteristics of the notch filter to perform targeted deep attenuation of the residual fourth harmonic component. In other words, with the second harmonic suppressed and the lowest interference frequency shifted to the fourth order, further filtering of the fourth harmonic energy allows for a wider bandwidth design without affecting conversion accuracy, balancing the system's tracking response speed and angle conversion accuracy.

[0056] In summary, the phase detection signal processing method for the rotary transformer conversion system proposed in this invention addresses the technical problem that traditional phase detection methods, whether using sine waves or square waves, inevitably generate the second harmonic of the excitation signal. The subsequent filtering to reduce this influence leads to a trade-off between accuracy and bandwidth, resulting in performance limitations. By superimposing a third harmonic phase detection signal component and pre-setting its amplitude, the phase detection output signal is free from the second harmonic, thus alleviating the trade-off between accuracy and bandwidth in traditional systems. Furthermore, in the phase detection output signal generation and synchronous phase detection processing stages of this invention, notch filtering technology can be incorporated at the front end of the Type II tracking loop to suppress higher-order harmonics, further enhancing the balance between tracking response speed and accuracy.

[0057] On the other hand, embodiments of the present invention also provide a resolver decoding chip, such as... Figure 6 As shown, the resolver decoding chip 600 includes: The signal input interface 610 is used to receive the sine and cosine signals modulated by the excitation frequency from the rotary transformer.

[0058] Specifically, such as Figure 6 As shown, the front-end input interface 610 includes a first interface 611 for receiving an initial sine signal and a second interface 612 for receiving an initial cosine signal.

[0059] The phase detection signal generation circuit 620 is used to generate a first phase detection signal component and a second phase detection signal component; the first phase detection signal component is in phase and frequency with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency.

[0060] The synchronous phase detection circuit 630 is connected to the phase detection signal generation circuit and is used to synchronously phase-detect the first phase detection signal component and the second phase detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, so as to obtain the first phase detection output signal and the second phase detection output signal. The preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out.

[0061] Angle generation circuit 640, connected to synchronous phase detection circuit, is used to generate the angle value of resolver decoding based on the first phase detection output signal and the second phase detection output signal.

[0062] Specifically, the angle generation circuit 640 is a Type II tracking loop, such as... Figure 6 As shown, SIN0 and COS0 refer to the signals containing angle information extracted after synchronous phase detection. The specific working process of the Type II tracking loop 630 is as follows: SIN / COS unit, output tracking signal , , It's the tracking angle.

[0063] The error synthesis unit synthesizes the error angle between the input angle and the tracking angle.

[0064] The purpose of the Type II tracking loop 630 is to ensure that the tracking angle quickly tracks the input angle:

[0065] When tracking the input angle, the output of the error synthesis unit tends to zero; otherwise, it continues to track.

[0066] The SIN / COS unit's angle output is a relatively ideal internal angle signal; if the input angle deviates, this deviation is directly reflected in the internal angle signal, i.e., the tracking angle accuracy, which is in principle directly determined by the input angle. Here, the filter in the Type II tracking loop suppresses harmonic terms of the input angle through filtering.

[0067] It should be understood that the filters, angular velocity integrators, and position integrators in the Type II tracking loop are all mature technologies and will not be elaborated upon here.

[0068] The signal output interface 650 is used to output angle values ​​to peripherals or internal control chips.

[0069] The control chip for the peripheral device can be a chip used in different application scenarios, which will not be elaborated on here.

[0070] The resolver decoding chip 600 provided in the above embodiments can implement the technical solutions described in the embodiments of the phase detection signal processing method of the resolver conversion system. The specific implementation principles of each circuit can be found in the corresponding content of the embodiments of the phase detection signal processing method of the resolver conversion system, which will not be repeated here.

[0071] On the other hand, embodiments of the present invention also provide a rotary transformer conversion system, such as Figure 7 As shown, the resolver conversion system 700 includes: a resolver decoding chip 600 and a peripheral chip 701; The resolver decoding chip 600 is the resolver decoding chip in any of the above embodiments; Peripheral chip 701 is connected to resolver decoding chip 600 and is used to receive angle values ​​generated by resolver decoding chip 600.

[0072] In a practical application scenario, peripheral chip 701 is a motor control microcontroller (MCU) or digital signal processor (DSP). The resolver decoder chip 600 sends the decoded angle value to peripheral chip 701 via an SPI interface or a parallel interface.

[0073] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.), and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0074] The phase detection signal processing method, chip, and system of a rotary transformer conversion system provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A phase detection signal processing method for a rotary transformer conversion system, used to synchronously detect the phase of a sinusoidal signal and a cosine signal modulated by an excitation frequency output from the rotary transformer, characterized in that, include: Acquire the first phase detection signal component and the second phase detection signal component; The first phase detection signal component is in phase and frequency with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency. Based on a preset amplitude ratio, the first phase detection signal component and the second phase detection signal component are synchronously phase-detected with the sine signal and the cosine signal, respectively, to obtain the first phase detection output signal and the second phase detection output signal; the first phase detection output signal and the second phase detection output signal include a DC component related to the rotation angle of the rotary transformer; The preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out.

2. The phase detection signal processing method for the rotary transformer conversion system according to claim 1, characterized in that, The step of synchronously phase-detecting the first phase-detection signal component and the second phase-detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, and obtaining the corresponding first phase-detection output signal and second phase-detection output signal, includes: The first phase detection signal component and the second phase detection signal component are superimposed at the preset amplitude ratio to obtain a composite phase detection signal; The composite phase detection signal is multiplied by the sine signal and the cosine signal respectively for synchronous phase detection, thereby obtaining the first phase detection output signal and the second phase detection output signal.

3. The phase detection signal processing method for the rotary transformer conversion system according to claim 1, characterized in that, The step of synchronously phase-detecting the first phase-detection signal component and the second phase-detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, and obtaining the corresponding first phase-detection output signal and second phase-detection output signal, includes: The first phase detection signal component is multiplied by the sine signal and the cosine signal respectively to obtain the first mixing signal and the second mixing signal. The second phase detection signal component is multiplied by the sine signal and the cosine signal respectively to obtain the third mixing signal and the fourth mixing signal. The first mixing signal and the third mixing signal are superimposed with the preset amplitude ratio to obtain the first phase detection output signal, and the second mixing signal and the fourth mixing signal are superimposed with the preset amplitude ratio to obtain the second phase detection output signal.

4. The phase detection signal processing method for the rotary transformer conversion system according to claim 1, characterized in that, The first phase detection signal component and the second phase detection signal component have the same signal type.

5. The phase detection signal processing method for the rotary transformer conversion system according to claim 4, characterized in that, When the first phase detection signal component is a sine wave signal, the preset amplitude ratio is 1.

6. The phase detection signal processing method for the rotary transformer conversion system according to claim 4, characterized in that, When the first phase detection signal component is a square wave signal, the amplitude of the second phase detection signal component is 2 / 3 of the amplitude of the first phase detection signal component.

7. The phase detection signal processing method for the rotary transformer conversion system according to claim 4, characterized in that, When the first phase detection signal component is a square wave signal, the amplitude of the second phase detection signal component is 5 / 8 of the amplitude of the first phase detection signal component.

8. The phase detection signal processing method for a rotary transformer conversion system according to any one of claims 1-7, characterized in that, Also includes: The first phase detection output signal and the second phase detection output signal are filtered by a notch filter to obtain a first optimized output signal and a second optimized output signal. The center frequency of the notch filter is configured to be four times the excitation frequency.

9. A resolver decoding chip, characterized in that, include: The signal input interface is used to receive the sinusoidal and cosine signals modulated by the excitation frequency from the rotary transformer. A phase detection signal generation circuit is used to generate a first phase detection signal component and a second phase detection signal component. The first phase detection signal component is in phase and frequency with the excitation signal, and the frequency of the second phase detection signal component is three times the excitation frequency. A synchronous phase detection circuit, connected to the phase detection signal generation circuit, is used to synchronously phase-detect the first phase detection signal component and the second phase detection signal component with the sine signal and the cosine signal respectively based on a preset amplitude ratio, thereby obtaining a first phase detection output signal and a second phase detection output signal; wherein, the preset amplitude ratio is configured such that the second harmonic component generated by the first phase detection signal component and the second harmonic component generated by the second phase detection signal component in the phase detection output signal at least partially cancel each other out; An angle generation circuit, connected to the synchronous phase detection circuit, is used to generate the angle value of the resolver decoder based on the first phase detection output signal and the second phase detection output signal. The signal output interface is used to output the angle value to an external device or an internal control chip.

10. A rotary transformer conversion system, characterized in that, include: Resolver decoding chip and peripheral chip; The resolver decoding chip is the resolver decoding chip described in claim 9; The peripheral chip is used to receive the angle value generated by the resolver decoding chip.

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