Resolver analog device and method based on a multiplying digital-to-analog converter
Patent Information
- Application Number
- CN202611157501.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-31
- Publication Date
- 2026-10-30
AI Technical Summary
本申请提供的一种基于乘法型数模转换器的旋转变压器模拟装置，以乘法型数模转换器替代传统模拟乘法器或数字信号处理方案，通过将激励信号直接作为参考电压实现无相位差的旋转变压器信号模拟。首先，该装置以增益可调放大器、第一乘法型数模转换电路、第二乘法型数模转换电路和控制逻辑电路构成信号链路，增益可调放大器接收旋转变压器激励信号并对其幅值进行调节，输出波形和相位与激励信号完全一致的信号，作为两路乘法型数模转换电路的共享参考电压；控制逻辑电路根据旋转变压器待模拟角度，分别控制两路乘法型数模转换电路将参考电压转换为正弦反馈信号和余弦反馈信号。整个信号链路中，激励信号直接作为参考电压参与乘法运算，不经过模数转换和数字信号处理环节，因此反馈信号与激励信号之间不存在相位延迟，从原理上消除了传统数字方案因模数转换和数字处理引入的相位差，避免了相位补偿电路带来的硬件复杂度。其次，该装置仅需增益可调放大器、乘法型数模转换器和控制逻辑电路即可实现完整功能，无需模拟乘法器、模数转换器等器件，结构简单、成本低。由于乘法型数模转换器工作在四象限模式，输出信号与参考电压的同相或反相关系由输入数字量决定，误差主要来源于乘法型数模转换器的线性度和分辨率，与模拟乘法器方案相比避免了温度漂移和非线性失真问题，精度和稳定性更高。通过改变控制逻辑电路输出的数字量即可实现0至360度全范围角度模拟，分辨率取决于数模转换器位数，灵活性和扩展性强。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of analog rotary transformer signal technology, specifically to a rotary transformer simulation device and method based on a multiplicative digital-to-analog converter. Background Technology
[0002] Resolver transformers, as highly reliable angular displacement sensors, are widely used in motor control, servo systems, aerospace, and industrial automation. They output orthogonal modulated signals related to the rotor angle through electromagnetic induction, offering advantages such as strong anti-interference capabilities and good environmental adaptability. Resolver simulation devices play a crucial role in system verification, providing a reliable testing and verification environment for motor control systems, servo drives, and aerospace equipment by accurately simulating the signal characteristics of resolvers.
[0003] Currently, rotary transformer simulation devices mainly employ analog multipliers, digital signal processors (DSPs) combined with analog-to-digital converters (ADCs), and digital-to-analog converters (DACs). Analog multiplier solutions suffer from large temperature drift, poor linearity, and low accuracy. While digital solutions offer higher accuracy, the analog-to-digital conversion and digital signal processing introduce phase delays, causing a phase difference between the feedback and excitation signals. This necessitates additional phase compensation circuitry, increasing hardware design complexity and cost. Furthermore, existing solutions struggle to balance dynamic performance and accuracy. Therefore, there is an urgent need for a rotary transformer simulation device that is simple in principle, highly accurate, low-cost, and capable of eliminating phase differences. Summary of the Invention
[0004] To address the problems existing in the prior art, this invention provides a rotary transformer simulation device and method based on a multiplicative digital-to-analog converter. With the multiplicative digital-to-analog converter as the core, it achieves synchronous output of the feedback signal and the excitation signal without phase difference by directly using the excitation signal as the reference voltage of the digital-to-analog converter. It has the advantages of simple principle, high accuracy and low cost.
[0005] This invention is achieved through the following technical solution: In a first aspect, this application provides a rotary transformer simulation device based on a multiplicative digital-to-analog converter, including a gain-adjustable amplifier, a first multiplicative digital-to-analog converter circuit, a second multiplicative digital-to-analog converter circuit, and a control logic circuit; The gain-adjustable amplifier adjusts the amplitude of the input rotary transformer excitation signal and outputs a signal with the same waveform and phase as the rotary transformer excitation signal; the output terminal of the gain-adjustable amplifier is simultaneously connected to the reference voltage input terminals of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit. The first multiplicative digital-to-analog converter (DAC) and the second multiplicative DAC use the output signal of the gain-adjustable amplifier as a reference voltage. The control logic circuit controls the first multiplicative DAC to convert the reference voltage into a sinusoidal feedback signal of the rotary transformer, and controls the second multiplicative DAC to convert the reference voltage into a cosine feedback signal of the rotary transformer, based on the angle to be simulated by the rotary transformer.
[0006] Preferably, the gain-adjustable amplifier is a PGA programmable amplifier, with a gain selectable range of 1 / 8, 1 / 4, 1 / 2, 1, 2, 4 and 8.
[0007] Preferably, both the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit operate in four-quadrant mode; The control logic circuit controls the first multiplicative digital-to-analog converter circuit to output a voltage signal proportional to sin(θ), and controls the second multiplicative digital-to-analog converter circuit to output a voltage signal proportional to cos(θ), where θ is the angle to be simulated by the rotary transformer.
[0008] Preferably, when the code value corresponding to sin(θ) is positive, the output signal of the first multiplicative digital-to-analog converter is in phase with the reference voltage; when the code value corresponding to sin(θ) is negative, the output signal is out of phase with the reference voltage.
[0009] Preferably, the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit output a negative reference voltage value when all data terminals are 0, and output a positive reference voltage value when all data terminals are 1.
[0010] Preferably, the code value of the first multiplicative digital-to-analog converter is obtained by mapping sin(θ), and the code value of the second multiplicative digital-to-analog converter is obtained by mapping cos(θ), where θ is the angle to be simulated by the rotary transformer.
[0011] Preferably, the resolution of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit is 16 bits.
[0012] Preferably, it further includes an overvoltage protection circuit, wherein the rotary transformer excitation signal is connected to the input terminal of the gain adjustable amplifier via the overvoltage protection circuit; the rotary transformer sine feedback signal and the rotary transformer cosine feedback signal are output via the overvoltage protection circuit.
[0013] Preferably, the sinusoidal feedback signal and the cosine feedback signal of the rotary transformer are in phase with the excitation signal of the rotary transformer.
[0014] Secondly, this application provides a simulation method for a rotary transformer simulation device based on a multiplicative digital-to-analog converter, comprising the following steps: Step 1: Set the gain of the adjustable amplifier. After the amplitude of the rotary transformer excitation signal is adjusted by the adjustable amplifier, a reference voltage signal with the same waveform and phase as the rotary transformer excitation signal is obtained. Step 2: The first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit use the reference voltage signal as the reference voltage. The control logic circuit controls the first multiplicative digital-to-analog converter circuit to convert the reference voltage into a sinusoidal feedback signal of the rotary transformer according to the angle to be simulated by the rotary transformer, and controls the second multiplicative digital-to-analog converter circuit to convert the reference voltage into a cosine feedback signal of the rotary transformer.
[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This application provides a resolver simulation device based on a multiplicative digital-to-analog converter (DAC). The DAC replaces traditional analog multipliers or digital signal processing schemes, achieving phase-difference-free resolver signal simulation by directly using the excitation signal as the reference voltage. First, the device uses a gain-adjustable amplifier, a first multiplicative DAC circuit, a second multiplicative DAC circuit, and control logic circuits to form a signal link. The gain-adjustable amplifier receives the resolver excitation signal and adjusts its amplitude, outputting a signal with waveform and phase completely consistent with the excitation signal, serving as the shared reference voltage for the two multiplicative DAC circuits. The control logic circuit, based on the angle of the resolver to be simulated, controls the two multiplicative DAC circuits to convert the reference voltage into a sine feedback signal and a cosine feedback signal, respectively. In the entire signal link, the excitation signal directly participates in the multiplication operation as the reference voltage, without going through analog-to-digital conversion or digital signal processing stages. Therefore, there is no phase delay between the feedback signal and the excitation signal, fundamentally eliminating the phase difference introduced by analog-to-digital conversion and digital processing in traditional digital schemes, and avoiding the hardware complexity caused by phase compensation circuits. Secondly, this device only requires a gain-adjustable amplifier, a multiplicative digital-to-analog converter (DAC), and control logic circuitry to achieve complete functionality, eliminating the need for analog multipliers, analog-to-digital converters, and other components, resulting in a simple structure and low cost. Since the multiplicative DAC operates in four-quadrant mode, the in-phase or out-of-phase relationship between the output signal and the reference voltage is determined by the input digital quantity. The error mainly originates from the linearity and resolution of the multiplicative DAC. Compared to analog multiplier solutions, it avoids temperature drift and nonlinear distortion problems, offering higher accuracy and stability. By changing the digital quantity output by the control logic circuitry, a full-range angle simulation from 0 to 360 degrees can be achieved. The resolution depends on the number of bits in the DAC, providing strong flexibility and scalability. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a functional principle block diagram of the rotary transformer simulation device based on a multiplication-type digital-to-analog converter of the present invention; Figure 2 This is a schematic diagram of the multiplication-type digital-to-analog converter of the present invention. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0019] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0021] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0022] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0023] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0024] A rotary transformer simulation device based on a multiplicative digital-to-analog converter includes a gain-adjustable amplifier, a first multiplicative digital-to-analog converter circuit, a second multiplicative digital-to-analog converter circuit, and a control logic circuit. The gain-adjustable amplifier adjusts the amplitude of the input rotary transformer excitation signal and outputs a signal with the same waveform and phase as the rotary transformer excitation signal; the output terminal of the gain-adjustable amplifier is simultaneously connected to the reference voltage input terminals of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit. The first multiplicative digital-to-analog converter (DAC) and the second multiplicative DAC use the output signal of the gain-adjustable amplifier as a reference voltage. The control logic circuit controls the first multiplicative DAC to convert the reference voltage into a sinusoidal feedback signal of the rotary transformer, and controls the second multiplicative DAC to convert the reference voltage into a cosine feedback signal of the rotary transformer, based on the angle to be simulated by the rotary transformer.
[0025] This device uses a multiplicative digital-to-analog converter (DAC) as its core, achieving phase-difference-free resolution transformer signal simulation by directly using the excitation signal as the reference voltage. A gain-adjustable amplifier adjusts the amplitude of the input resolution transformer excitation signal, outputting a signal whose waveform and phase are consistent with the excitation signal, serving as the shared reference voltage for both the first and second multiplicative DAC circuits. The control logic circuit, based on the angle of the resolution transformer to be simulated, controls the two multiplicative DAC circuits to convert the reference voltage into sinusoidal and cosine feedback signals, respectively. Since the multiplicative DAC operates in four-quadrant mode, whether the output signal is in phase or out of phase with the reference voltage depends on the input digital quantity. The entire conversion process does not involve analog-to-digital sampling or digital signal processing, therefore there is no phase delay between the feedback signal and the excitation signal. This device only requires a gain-adjustable amplifier, a multiplicative DAC, and control logic circuitry to simulate resolution transformer signals, eliminating the need for analog multipliers, analog-to-digital converters, or complex phase compensation circuits, resulting in a simple structure and low cost. Compared with the digital scheme, it eliminates the influence of phase difference on angle accuracy in principle, and the error mainly comes from the linearity and resolution of the multiplicative digital-to-analog converter; compared with the analog multiplier scheme, it avoids temperature drift and nonlinear distortion problems, and has higher accuracy and stability.
[0026] In some embodiments, the gain-adjustable amplifier is a PGA programmable amplifier. The PGA programmable amplifier adjusts the amplitude of the input resolver excitation signal, and the waveform and phase of the output signal are completely consistent with the input excitation signal. The value of gain k is determined according to the turns ratio characteristics of the resolver, so that the amplitude of the reference voltage signal matches the input range requirements of the subsequent multiplicative digital-to-analog converter circuit.
[0027] Preferably, the PGA programmable amplifier is the PGA855 from TI. This device has selectable gain ranges of 1 / 8, 1 / 4, 1 / 2, 1, 2, 4, and 8, configurable via three I / O pins.
[0028] Furthermore, the gain-adjustable amplifier can also be implemented using a digital potentiometer in conjunction with a fixed-gain operational amplifier, with the gain changed by adjusting the resistance value of the digital potentiometer; alternatively, a programmable gain amplifier can be used, with the gain range and step accuracy flexibly selected according to the actual characteristics of the rotary transformer.
[0029] In some embodiments, both the first multiplication-type digital-to-analog converter circuit and the second multiplication-type digital-to-analog converter circuit use the AD5546BRUZ from Analog Devices, with a resolution of 16 bits. Their principles are as follows: Figure 2As shown. The AD5546BRUZ is powered by ±15V. When the ROFS pin is connected to the R1 pin, the device operates in four-quadrant mode, with the reference voltage being either positive or negative, and the output voltage being either in phase or out of phase with the reference voltage. In this embodiment, both multiplication-type digital-to-analog converter circuits are configured in four-quadrant operating mode.
[0030] In four-quadrant operation mode, the phase relationship between the output signal and the reference voltage of the multiplicative digital-to-analog converter (DAC) is determined by the sign of the input code value: when the multiplier value corresponding to the input code value is positive, the output signal is in phase with the reference voltage; when the multiplier value corresponding to the input code value is negative, the output signal is out of phase with the reference voltage. Specifically, when all 16 data bits are 0, the multiplier value is -1, and the DAC outputs -V. REF That is, the output signal is inverted compared to the reference voltage; when all 16 data bits are 1, the multiplier value is +1, and the multiplicative digital-to-analog converter outputs +V. REF That is, the output signal is in phase with the reference voltage.
[0031] The control logic circuit outputs code values to the first multiplicative digital-to-analog converter (DAC) circuit and the second multiplicative DAC circuit, respectively, based on the angle θ to be simulated by the rotary transformer. The code value of the first multiplicative DAC circuit is obtained by mapping sin(θ), and the code value of the second multiplicative DAC circuit is obtained by mapping cos(θ).
[0032] When the angle of the simulated rotary transformer is θ, the control logic circuit outputs the code value [32768 + 32767 * sin(θ)] to the first multiplicative digital-to-analog converter circuit, and the output voltage of the first multiplicative digital-to-analog converter circuit is V. REF *sin(θ); The control logic circuit outputs the code value [32768+32767*cos(θ)] to the second multiplicative digital-to-analog converter circuit, and the output voltage of the second multiplicative digital-to-analog converter circuit is V. REF *cos(θ). Where V REF The voltage signal applied to the reference voltage pin, i.e., the output of the gain-adjustable amplifier. k*U 0 *SIN(ωt) .
[0033] Furthermore, multiplicative digital-to-analog converters can also use 12-bit or 14-bit resolution devices to reduce costs and are suitable for applications with lower accuracy requirements. Multiplicative digital-to-analog converters can also use DAC8812 or AD5453.
[0034] In some embodiments, the control logic circuit generates digital quantities corresponding to sin(θ) and cos(θ) based on the angle θ to be simulated by the rotary transformer by looking up a table or by real-time calculation, and outputs them to the data terminals of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit, respectively.
[0035] Furthermore, the control logic circuit can be implemented using an FPGA, CPLD, or microcontroller, and communicates with the multiplicative digital-to-analog converter circuit via an SPI interface.
[0036] The control logic circuit can also pre-store sine and cosine lookup tables, quickly obtain code values by looking up the tables, and reduce real-time calculation overhead; it can also use the CORDIC algorithm to calculate sine and cosine values in real time to reduce storage space usage.
[0037] In some embodiments, the rotary transformer simulation device further includes an overvoltage protection circuit. The rotary transformer excitation signal is connected to the input terminal of the gain-adjustable amplifier via the overvoltage protection circuit; the sine feedback signal output by the first multiplicative digital-to-analog converter circuit and the cosine feedback signal output by the second multiplicative digital-to-analog converter circuit are respectively output to the rotary transformer conditioning circuit after passing through the overvoltage protection circuit.
[0038] Preferably, the overvoltage protection circuit uses a TVS diode in conjunction with a current-limiting resistor to prevent large voltage signals from the rotary transformer conditioning circuit from damaging the internal circuitry of the analog device.
[0039] Preferably, the overvoltage protection circuit can also be implemented using a Schottky diode clamping circuit or a dedicated overvoltage protection chip.
[0040] Example 1 A rotary transformer simulation device based on a multiplicative digital-to-analog converter includes: an overvoltage protection circuit, a PGA programmable amplifier, a first multiplicative digital-to-analog converter circuit, a second multiplicative digital-to-analog converter circuit, and a control logic circuit.
[0041] The overvoltage protection circuit provides overvoltage protection for the rotary transformer simulation device, preventing high-voltage signals from the rotary transformer conditioning circuit from damaging the internal circuitry. The rotary transformer excitation signal is connected to the input of the PGA programmable amplifier via the overvoltage protection circuit. The output of the PGA programmable amplifier is simultaneously connected to the voltage reference inputs of the first multiplicative digital-to-analog converter (DAC) and the second multiplicative DAC. The output signal of the first multiplicative DAC, after passing through the overvoltage protection circuit, forms a sinusoidal feedback signal for the rotary transformer. The output signal of the second multiplicative DAC, after passing through the overvoltage protection circuit, forms a cosine feedback signal for the rotary transformer. The output of the control logic circuit is connected to the control inputs of the first and second multiplicative DACs, respectively.
[0042] In this embodiment, the PGA programmable amplifier can amplify or reduce the amplitude of the excitation signal according to the characteristics of the rotary transformer, while the waveform and phase of the output signal of the PGA programmable amplifier remain unchanged. The PGA programmable amplifier selected is the PGA855 from TI, and the gain can be selected as 1 / 8, 1 / 4, 1 / 2, 1, 2, 4 and 8, configured through 3 IO pins.
[0043] In this embodiment, the principles of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit are as follows: Figure 2 As shown, the operational amplifier is powered by ±15V, and the multiplicative digital-to-analog converter is the AD5546BRUZ from Analog Devices, with a resolution of 16 bits.
[0044] When the ROFS pin is connected to the R1 pin, the AD5546BRUZ operates in four-quadrant mode, with either a positive or negative reference voltage, and the output can be in phase or out of phase with the reference voltage. When the ROFS pin is connected to the RFB pin, the AD5546BRUZ operates in unipolar two-quadrant mode, with either a positive or negative reference voltage, and the output can only be in phase with the reference voltage. In this embodiment, the AD5546BRUZ operates in four-quadrant mode.
[0045] In this embodiment, when all 16 data bits are 0, the first multiplication-type digital-to-analog converter and the second multiplication-type digital-to-analog converter output -VREF; when all 16 data bits are 1, the first multiplication-type digital-to-analog converter and the second multiplication-type digital-to-analog converter output +VREF.
[0046] When the angle of the analog rotary transformer is θ, let the code value of the multiplicative digital-to-analog converter circuit 1 be [32768 + 32767 * sin(θ)], then the output voltage of the first multiplicative digital-to-analog converter circuit is V. REF *sin(θ); Let the code value of the second multiplication type digital-to-analog converter be [32768+32767*cos(θ)], then the output voltage of the multiplication type digital-to-analog converter 2 is V. REF *cos(θ).
[0047] The operation of the rotary transformer simulation device in this embodiment includes the following steps: Step 1: Set the gain k of the PGA programmable amplifier according to the characteristics of the resolver. The gain can be selected in the range of 1 / 8, 1 / 4, 1 / 2, 1, 2, 4, and 8. (Resolver excitation signal) U 0 *SIN(ωt) The reference voltage signal is obtained after passing through a PGA programmable amplifier. k*U 0 *SIN(ωt) ; Step 2: Apply the reference voltage signal to the reference voltage pins of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit. Both the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit operate in four-quadrant mode. The control logic circuit, based on the angle θ to be simulated by the rotary transformer, outputs a digital quantity corresponding to sin(θ) to the first multiplicative digital-to-analog converter circuit and a digital quantity corresponding to cos(θ) to the second multiplicative digital-to-analog converter circuit; the output voltage of the first multiplicative digital-to-analog converter circuit is V. REF *sin(θ), the output voltage of the second multiplicative digital-to-analog converter circuit is V. REF *cos(θ).
[0048] Step 3: The signals output from the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit are respectively passed through the overvoltage protection circuit to form a sine feedback signal and a cosine feedback signal of the rotary transformer with the same phase as the excitation signal and whose amplitude includes sine and cosine information of angle θ. These signals are then output to the rotary transformer conditioning circuit, thus realizing the simulation of the rotary transformer signal.
[0049] In this embodiment, the sinusoidal feedback signal and cosine feedback signal of the rotary transformer are in phase with the excitation signal of the rotary transformer, and the phase difference is zero, which eliminates the phase delay introduced by analog-to-digital conversion and digital signal processing in principle.
[0050] This rotary transformer simulation device can be used in the hardware-in-loop testing of full authority digital electronic control systems for various types of aero engines. It has been verified by electronic controllers of various types of generators and can achieve accurate simulation of rotary transformer position information with a simulation angle resolution of 16 bits, enabling simulation of the full range from 0 to 360°.
[0051] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.
Claims
1. A resolver analog device based on a multiplication type digital-to-analog converter, characterized by, It includes a gain-adjustable amplifier, a first multiplicative digital-to-analog converter circuit, a second multiplicative digital-to-analog converter circuit, and a control logic circuit; The gain-adjustable amplifier adjusts the amplitude of the input rotary transformer excitation signal and outputs a signal with the same waveform and phase as the rotary transformer excitation signal; the output terminal of the gain-adjustable amplifier is simultaneously connected to the reference voltage input terminals of the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit. The first multiplicative digital-to-analog converter (DAC) and the second multiplicative DAC use the output signal of the gain-adjustable amplifier as a reference voltage. The control logic circuit controls the first multiplicative DAC to convert the reference voltage into a sinusoidal feedback signal of the rotary transformer, and controls the second multiplicative DAC to convert the reference voltage into a cosine feedback signal of the rotary transformer, based on the angle to be simulated by the rotary transformer.
2. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, The gain-adjustable amplifier is a PGA programmable amplifier with a gain selectable range of 1 / 8, 1 / 4, 1 / 2, 1, 2, 4 and 8.
3. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, Both the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit operate in four-quadrant mode; The control logic circuit controls the first multiplicative digital-to-analog converter circuit to output a voltage signal that is proportional to sin(θ); The control logic circuit controls the second multiplicative digital-to-analog converter circuit to output a voltage signal proportional to cos(θ), where θ is the angle to be simulated by the rotary transformer.
4. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 3, characterized in that, When the code value corresponding to sin(θ) is positive, the output signal of the first multiplicative digital-to-analog converter circuit is in phase with the reference voltage. When the code value corresponding to sin(θ) is negative, the output signal is out of phase with the reference voltage.
5. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, When the data terminals of the first multiplicative digital-to-analog converter and the second multiplicative digital-to-analog converter are all 0, they output a negative reference voltage value. When all values at the data terminal are 1, a positive reference voltage value is output.
6. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, The code value of the first multiplicative digital-to-analog converter is obtained by mapping sin(θ), and the code value of the second multiplicative digital-to-analog converter is obtained by mapping cos(θ), where θ is the angle to be simulated by the rotary transformer.
7. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, The resolution of both the first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit is 16 bits.
8. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, It also includes an overvoltage protection circuit, through which the rotary transformer excitation signal is connected to the input terminal of the gain-adjustable amplifier; the rotary transformer sine feedback signal and the rotary transformer cosine feedback signal are output through the overvoltage protection circuit.
9. The rotary transformer simulation device based on a multiplication-type digital-to-analog converter according to claim 1, characterized in that, The sinusoidal feedback signal and the cosine feedback signal of the rotary transformer are in phase with the excitation signal of the rotary transformer.
10. A simulation method for a rotary transformer simulation device based on a multiplicative digital-to-analog converter as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Set the gain of the adjustable amplifier. After the amplitude of the rotary transformer excitation signal is adjusted by the adjustable amplifier, a reference voltage signal with the same waveform and phase as the rotary transformer excitation signal is obtained. Step 2: The first multiplicative digital-to-analog converter circuit and the second multiplicative digital-to-analog converter circuit use the reference voltage signal as the reference voltage. The control logic circuit controls the first multiplicative digital-to-analog converter circuit to convert the reference voltage into a sinusoidal feedback signal of the rotary transformer according to the angle to be simulated by the rotary transformer, and controls the second multiplicative digital-to-analog converter circuit to convert the reference voltage into a cosine feedback signal of the rotary transformer.