Low-speed vehicle rotary transformer excitation voltage amplification circuit

Abstract

The utility model discloses a low-speed vehicle rotary transformer excitation voltage amplification circuit, comprising an operational amplifier U1 used for acquiring an excitation signal, processing the excitation signal and outputting the processed excitation signal to a bias in-phase amplifier; the bias in-phase amplification unit is used for amplifying and biasing the excitation signal and then outputting a standard positive rotation wave; and the filtering unit is used for filtering the standard positive rotation wave and then outputting the filtered standard positive rotation wave to the rotary transformer sensor. According to the low-speed vehicle rotary transformer excitation voltage amplification circuit, coupling output is achieved through the capacitor C3, and direct-current interference signals are reduced; a large-current operational amplifier is used, so that the use of push-pull Mos is reduced; a capacitor C3 is used for zero-crossing output, and one path of excitation output is reduced; by adopting the characteristics of the capacitor C3 and the operational amplifier U1, the problem that decoding is unreliable due to the fact that signal distortion occurs and output signal parameters are not within a preset range in the existing rotary transformer circuit technology can be solved; and the capacitor C3 and the operational amplifier U1 are adopted, so that the structure is simple and the cost is low.

Description

Technical Field

[0001] The utility model relates to the technical field of low-speed vehicle resolvers, in particular to a low-speed vehicle resolver excitation voltage amplifier circuit. Background Art

[0002] The working principle of resolver requires a high-frequency sinusoidal signal input, which we usually call an excitation signal.

[0003] The existing technology uses simple gain adjustment and bias voltage adjustment to adapt to different resolver ratios to avoid problems such as excitation amplitude mismatch and response signal mismatch caused by synchronous amplification of DC components and AC voltages; or uses the characteristics of capacitors to solve the problem of signal distortion and output signal parameters not being within a preset range in existing resolver circuit technology, resulting in unreliable decoding.

[0004] However, the above resolver circuits all have the problems of high complexity, many components and high cost. Summary of the invention

[0005] The utility model aims to provide a low-speed vehicle resolver excitation voltage amplifier circuit.

[0006] To achieve the above purpose, the utility model provides the following technical solution: a low-speed vehicle resolver excitation voltage amplifier circuit, comprising:

[0007] Operational amplifier U1, used to obtain the excitation signal, process it and output it to the biased common-phase amplifier;

[0008] A biased in-phase amplifier unit, used to amplify the excitation signal and output a standard sine wave after biasing; and

[0009] The filtering unit is used to filter the standard sine wave and then output it to the resolver sensor.

[0010] Furthermore, the biased in-phase amplifier unit includes resistors R1, R2, and R3. The resistors R1 and R2 are connected in parallel and connected to the resistor R3. Pin 2 of the operational amplifier U1 is connected between the resistors R1, R2, and R3.

[0011] Furthermore, the filtering unit includes resistors R5, R6, capacitors C3, and C4. The capacitor C3 and resistor R5 are connected in series, and one end is connected to C2 and R3 in parallel, and the other end is connected to the resolver sensor. One end of the resistor R6 is connected to C4, and the other end of R6 is connected between C3 and R5.

[0012] Furthermore, it also includes a voltage dividing unit for obtaining a voltage and then dividing it to power the operational amplifier U1. The voltage dividing unit includes resistors R7 and R8. The resistors R7 and R8 are connected in series and connected to the 5th pin of the operational amplifier U1.

[0013] Furthermore, the pin 3 of the operational amplifier U1 is connected to a resistor R4, and one end of the resistor R4 is connected to an excitation signal.

[0014] Furthermore, the biased in-phase amplifier unit further includes capacitors C1 and C2, the capacitor C1 is connected in parallel with the resistors R1 and R2, and the capacitor C2 is connected in parallel with the resistor R3.

[0015] Furthermore, the model of the operational amplifier U1 is AD8397ARZ.

[0016] It can be seen from the above technical solution that the utility model has the following beneficial effects:

[0017] The low-speed vehicle resolver excitation voltage amplifier circuit outputs through capacitor C3 coupling, thereby reducing DC interference signals; uses a large current operational amplifier to reduce the use of push-pull MOS; uses capacitor C3 for zero-crossing output to reduce one excitation output; by adopting the characteristics of capacitor C3 and operational amplifier U1, the problem of signal distortion and output signal parameters not being within a preset range in the existing resolver circuit technology, thereby causing unreliable decoding, can be solved; the capacitor C3 and operational amplifier U1 have a simple structure and low cost, thereby solving the technical problems of high complexity, many devices and high cost of the existing resolver circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the overall circuit diagram of the utility model. DETAILED DESCRIPTION

[0019] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] See also Figure 1 The utility model provides a low-speed vehicle resolver excitation voltage amplifier circuit, including an operational amplifier U1, a biased in-phase amplifier unit, a filter unit and a voltage divider unit, wherein the 3rd pin of the operational amplifier U1 is connected to one end of a resistor R4, one end of the resistor R4 is connected to an excitation signal EXCIN+, and the other end of R4 is connected to a DSP, wherein the voltage divider unit includes resistors R7 and R8, and the resistors R7 and R8 are connected in series and connected to the 5th pin of the operational amplifier U1;

[0023] The filtering unit includes resistors R5, R6, capacitors C3, and C4. The capacitor C3 and the resistor R5 are connected in series, and one end is connected to C2 and R3 in parallel, and the other end is connected to the resolver sensor. One end of the resistor R6 is connected to C4, and the other end of R6 is connected between C3 and R5.

[0024] The biased common-mode amplifier unit includes resistors R1, R2, R3, capacitors C1, C2. The capacitor C1, resistors R1, R2 are connected in parallel and then connected to C2 and R3 in parallel. Pin 2 of the operational amplifier U1 is connected between the resistors R1, R2 and R3.

[0025] Working principle: First, the +5V voltage is divided by R7 and R8 and input to the 5th pin of the operational amplifier U1. The 6th and 7th pins of the operational amplifier U1 are short-circuited to form a follower amplifier. At this time, the 7th pin of the operational amplifier outputs a voltage reference VREF; EXCIN+ is an excitation signal output by the DSP, which is input to the 3rd pin of the operational amplifier U1 through R4; VREF output from the 7th pin of the operational amplifier U1 is input to the 2nd pin of the operational amplifier U1 after passing through R1; R1, R2, and R3 form a biased common-phase amplifier to convert the excitation signal EXCIN+ into a CIN+ is amplified and biased and output from pin 1 of operational amplifier U1; C1 provides pole compensation here, and its main working principle is to lower the control bandwidth and reduce its gain to 0dB before the phase of the power part or the part with other compensation reaches 180 degrees; C2 plays a role of DC isolation and AC passing here, filtering out the DC component of the sinusoidal wave output by operational amplifier U1, leaving only the standard sine wave; the standard sine wave is output from pin 2 of C2, filtered by C3 and R6, and then transmitted to the resolver sensor in the motor through R5.

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-speed vehicle resolver excitation voltage amplifier circuit, characterized in that: include: Operational amplifier U1, used to obtain the excitation signal, process it and output it to the biased common-phase amplifier; A biased in-phase amplifier unit is used to amplify the excitation signal and output a standard sine wave after biasing; as well as The filtering unit is used to filter the standard sine wave and then output it to the resolver sensor.

2. A low-speed vehicle resolver excitation voltage amplifier circuit according to claim 1, characterized in that: The biased in-phase amplifier unit includes resistors R1, R2, and R3. The resistors R1 and R2 are connected in parallel and connected to the resistor R3. The pin 2 of the operational amplifier U1 is connected between the resistors R1, R2, and R3.

3. The low-speed vehicle resolver excitation voltage amplifier circuit according to claim 1, characterized in that: The filtering unit includes resistors R5, R6, capacitors C3, and C4. The capacitor C3 and the resistor R5 are connected in series, and one end is connected to C2 and R3 in parallel, and the other end is connected to the resolver sensor. One end of the resistor R6 is connected to C4, and the other end of R6 is connected between C3 and R5.

4. The low-speed vehicle resolver excitation voltage amplifier circuit according to claim 1, characterized in that: It also includes a voltage dividing unit for obtaining a voltage and dividing it to supply power to the operational amplifier U1. The voltage dividing unit includes resistors R7 and R8. The resistors R7 and R8 are connected in series and connected to the 5th pin of the operational amplifier U1.

5. The low-speed vehicle resolver excitation voltage amplifier circuit according to claim 1, characterized in that: Pin 3 of the operational amplifier U1 is connected to a resistor R4 , and one end of the resistor R4 is connected to an excitation signal.

6. The low-speed vehicle resolver excitation voltage amplifier circuit according to claim 2, characterized in that: The biased in-phase amplifier unit further includes capacitors C1 and C2. The capacitor C1 is connected in parallel with the resistors R1 and R2. The capacitor C2 is connected in parallel with the resistor R3.

7. The low-speed vehicle resolver excitation voltage amplifier circuit according to claim 2, characterized in that: The model of the operational amplifier U1 is AD8397ARZ.

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