Signal conversion circuit and sensor

Abstract

The utility model discloses a signal conversion circuit and a sensor, the circuit comprising: a first resistor voltage divider circuit, having a first input end for accessing a first phase voltage signal, having a second input end for accessing a second phase voltage signal, and also having a voltage output end, a first output end and a second output end; a second resistor voltage divider circuit, having a first input end for accessing a third phase voltage signal, and also having a third output end and a fourth output end, the second end of the second resistor voltage divider circuit is connected to the voltage output end of the first resistor voltage divider circuit; the utility model outputs a first differential signal and a second differential signal after voltage division processing of the first phase voltage signal, the second phase voltage signal and the third phase voltage signal through the first resistor voltage divider circuit and the second resistor voltage divider circuit; and changes the phase difference between the first differential signal and the second differential signal by adjusting the resistance distribution of the first resistor voltage divider circuit and the second resistor voltage divider circuit.

Description

Technical Field

[0001] The utility model relates to the technical field of three-phase measurement systems, in particular to a signal conversion circuit and a sensor. Background Art

[0002] In a three-phase measurement system, the three-phase signal is generally sampled, and the sampled signal is converted into a two-phase signal through software calculation, and used for subsequent algorithm processing.

[0003] The processing method of the existing technology uses relatively complex algorithm processing in the algorithm processing process from three phases to two phases, which occupies software computing power and has a certain time delay, which is not conducive to timely processing of signals. Utility Model Content

[0004] The main purpose of the utility model is to provide a signal conversion circuit, which aims to realize the conversion of three-phase signals into two-phase signals by using hardware circuits without occupying software resources.

[0005] To achieve the above object, the utility model proposes a signal conversion circuit; the circuit comprises:

[0006] A first resistor voltage divider circuit, wherein the first resistor voltage divider circuit has a first input terminal for receiving a first phase voltage signal, the first resistor voltage divider circuit has a second input terminal for receiving a second phase voltage signal, and the first resistor voltage divider circuit further has a voltage output terminal, a first output terminal, and a second output terminal;

[0007] The first resistor voltage divider circuit is used to output a first voltage through the voltage output terminal after voltage division processing of the first phase voltage signal and the second phase voltage signal, and to output a first differential signal through the first output terminal of the first resistor voltage divider circuit and the second output terminal of the first resistor voltage divider circuit;

[0008] a second resistor voltage divider circuit, wherein the second resistor voltage divider circuit has a first input terminal for receiving a third phase voltage signal, a second terminal of the second resistor voltage divider circuit is connected to a voltage output terminal of the first resistor voltage divider circuit, and the second resistor voltage divider circuit further has a third output terminal and a fourth output terminal;

[0009] The second resistor voltage divider circuit is used to divide the first voltage and the third phase voltage signal and then output a second differential signal through the third output terminal of the second resistor voltage divider circuit and the fourth output terminal of the second resistor voltage divider circuit.

[0010] Optionally, the first resistor voltage divider circuit includes:

[0011] a first resistor, a second resistor, a third resistor, and a fourth resistor;

[0012] The first end of the first resistor is connected to the first phase voltage signal, and the second end is connected to the first end of the second resistor; the second end of the second resistor is connected to the first end of the third resistor; the second end of the third resistor is connected to the second end of the fourth resistor; the first end of the fourth resistor is connected to the second phase voltage signal;

[0013] Among them, the second end of the first resistor is the first output end of the first resistor voltage divider circuit, the second end of the fourth resistor is the second output end of the first resistor voltage divider circuit; the second end of the second resistor is the voltage output end of the first resistor voltage divider circuit.

[0014] Optionally, the second resistor voltage divider circuit

[0015] a fifth resistor, a sixth resistor and a seventh resistor;

[0016] The first end of the fifth resistor is connected to the third phase voltage signal, and the second end is connected to the first end of the sixth resistor; the second end of the sixth resistor is connected to the second end of the seventh resistor; the first end of the seventh resistor is connected to the voltage output end of the first resistor voltage divider circuit;

[0017] Among them, the first end of the seventh resistor is the second end of the second resistor voltage divider circuit; the second end of the fifth resistor is the third output end of the second resistor voltage divider circuit, and the second end of the seventh resistor is the fourth output end of the second resistor voltage divider circuit.

[0018] Optionally, the circuit further includes:

[0019] An isolation circuit, whose input end is connected to the voltage output end of the first resistor voltage divider circuit, and whose output end is connected to the second end of the second resistor voltage divider circuit; the isolation circuit is used to isolate and output the first voltage to the second resistor voltage divider circuit.

[0020] Optionally, the isolation circuit includes:

[0021] A voltage follower, wherein the positive input terminal of the voltage follower is connected to the voltage output terminal of the first resistor voltage divider circuit, and the output terminal and the negative input terminal of the voltage follower are connected to the second terminal of the second resistor voltage divider circuit.

[0022] Optionally, the signal conversion circuit further includes:

[0023] A first phase current signal access terminal, used for accessing a first phase current signal;

[0024] A second phase current signal access terminal, used for accessing a second phase current signal;

[0025] A third-phase current signal access terminal, used for accessing a third-phase current signal;

[0026] a preprocessing circuit, wherein a first input terminal of the preprocessing circuit is connected to the first phase current signal access terminal, a second input terminal is connected to the second phase current signal access terminal, and a third input terminal is connected to the third phase current signal access terminal; a first output terminal of the preprocessing circuit is connected to the first input terminal of the first resistor voltage divider circuit, a second output terminal of the preprocessing circuit is connected to the second input terminal of the first resistor voltage divider circuit, and a third output terminal of the preprocessing circuit is connected to the first input terminal of the second resistor voltage divider circuit;

[0027] The preprocessing circuit is used to convert the first phase current signal into a first phase voltage signal and output it to the first input end of the first resistor divider circuit, and to convert the second phase current signal into a second phase voltage signal and output it to the second input end of the first resistor divider circuit; the preprocessing circuit is also used to convert the third phase current signal into a third phase voltage signal and output it to the first input end of the second resistor divider circuit.

[0028] Optionally, the preprocessing circuit includes:

[0029] A first bias voltage access terminal, used for accessing a first bias voltage;

[0030] A second bias voltage access terminal, used for accessing a second bias voltage;

[0031] a first signal conversion circuit, wherein the first input terminal is connected to the first bias voltage access terminal, the second input terminal is connected to the second bias voltage access terminal, and the third input terminal is connected to the first phase current signal access terminal; the first signal conversion circuit is used to convert the first phase current signal into the first phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the first input terminal of the first resistor divider circuit;

[0032] a second signal conversion circuit, wherein a first input terminal is connected to the first bias voltage access terminal, a second input terminal is connected to the second bias voltage access terminal, and a third input terminal is connected to the second phase current signal access terminal; the second signal conversion circuit is used to convert the second phase current signal into the second phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the second input terminal of the first resistor divider circuit;

[0033] A third signal conversion circuit, wherein the first input terminal is connected to the first bias voltage access terminal, the second input terminal is connected to the second bias voltage access terminal, and the third input terminal is connected to the third phase current signal access terminal; the third signal conversion circuit is used to convert the third phase current signal into the third phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the first input terminal of the second resistance voltage divider circuit.

[0034] Optionally, the first signal conversion circuit includes:

[0035] an eighth resistor, a ninth resistor, a tenth resistor and a first operational amplifier;

[0036] The first end of the tenth resistor is connected to the second bias voltage access terminal, and the second end is connected to the positive input terminal of the first operational amplifier; the negative input terminal of the first operational amplifier is connected to the first phase current signal access terminal; the first end of the eighth resistor is connected to the first bias voltage access terminal, and the second end is connected to the first end of the ninth resistor and the negative input terminal of the first operational amplifier; the second end of the ninth resistor is connected to the first input terminal of the first resistor voltage divider circuit.

[0037] Optionally, the first resistor voltage divider circuit further includes:

[0038] a seventeenth resistor and an eighteenth resistor;

[0039] The first end of the seventeenth resistor is connected to the second end of the first resistor, and the first end of the eighteenth resistor is connected to the second end of the third resistor.

[0040] The utility model also provides a sensor, which comprises the signal conversion circuit.

[0041] The utility model proposes a signal conversion circuit and a sensor; the signal conversion circuit comprises: a first resistor voltage divider circuit, the first resistor voltage divider circuit has a first input end for accessing a first phase voltage signal, the first resistor voltage divider circuit has a second input end for accessing a second phase voltage signal, and the first resistor voltage divider circuit also has a voltage output end, a first output end and a second output end; the first resistor voltage divider circuit is used to output a first voltage through the voltage output end after voltage division processing of the first phase voltage signal and the second phase voltage signal, and output a first differential signal through the first output end of the first resistor voltage divider circuit and the second output end of the first resistor voltage divider circuit; a second resistor voltage divider circuit, the second resistor voltage divider circuit has a first input end for accessing a third phase voltage signal, the second end of the second resistor voltage divider circuit is connected to the voltage output end of the first resistor voltage divider circuit, and the second resistor voltage divider circuit also has a third output end and a fourth output end; the second resistor voltage divider circuit is used to output a second differential signal through the first output end of the second resistor voltage divider circuit and the second output end of the second resistor voltage divider circuit after voltage division processing of the first voltage and the third phase voltage signal. The utility model outputs a first differential signal and a second differential signal after voltage division processing of the first phase voltage signal, the second phase voltage signal and the third phase voltage signal through a first resistor voltage divider circuit and a second resistor voltage divider circuit; and adjusts the phase difference between the first differential signal and the second differential signal by adjusting the resistance distribution of the first resistor voltage divider circuit and the second resistor voltage divider circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0043] Figure 1 This is a schematic diagram of the structure of an embodiment of a signal conversion circuit of the utility model;

[0044] Figure 2 This is a schematic diagram of the structure of another embodiment of the signal conversion circuit of the utility model;

[0045] Figure 3 This is a structural schematic diagram of another embodiment of the signal conversion circuit of the utility model;

[0046] Figure 4 This is a structural diagram of another embodiment of the signal conversion circuit of the utility model;

[0047] Figure 5 This is a structural diagram of another embodiment of the signal conversion circuit of the utility model;

[0048] Figure 6 It is a structural schematic diagram of another embodiment of the signal conversion circuit of the utility model.

[0049] Description of Figure Numbers:

[0050]

[0051]

[0052] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0053] 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 of 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.

[0054] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0055] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] In addition, in the present utility model, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0057] The utility model provides a signal conversion circuit.

[0058] Reference Figure 1 , the signal conversion circuit comprises: a first resistor voltage divider circuit 100, the first resistor voltage divider circuit 100 has a first input terminal for receiving a first phase voltage signal, the first resistor voltage divider circuit 100 has a second input terminal for receiving a second phase voltage signal, and the first resistor voltage divider circuit 100 also has a voltage output terminal, a first output terminal and a second output terminal;

[0059] The first resistor voltage divider circuit 100 is used to output a first voltage through the voltage output terminal after voltage division processing of the first phase voltage signal and the second phase voltage signal, and to output a first differential signal through the first output terminal of the first resistor voltage divider circuit 100 and the second output terminal of the first resistor voltage divider circuit 100;

[0060] a second resistor voltage divider circuit 200, wherein the second resistor voltage divider circuit 200 has a first input terminal for receiving a third phase voltage signal, a second terminal of the second resistor voltage divider circuit 200 is connected to a voltage output terminal of the first resistor voltage divider circuit 100, and the second resistor voltage divider circuit 200 further has a third output terminal and a fourth output terminal;

[0061] The second resistor voltage divider circuit 200 is used to divide the first voltage and the third phase voltage signal and then output a second differential signal through the third output terminal of the second resistor voltage divider circuit 200 and the fourth output terminal of the second resistor voltage divider circuit 200 .

[0062] It should be noted that the first phase voltage signal, the second phase voltage signal and the third phase voltage signal are all vectors, and there are phase differences between the three voltage signals; the three-phase to two-phase circuit is used to process the three-phase signal with phase differences to obtain a first differential signal and a second differential signal, wherein the difference between the phase of the first differential signal and the phase of the second differential signal is a predetermined phase difference. The predetermined phase difference can be determined by the R&D personnel, and the R&D personnel can construct the first resistor voltage divider circuit 100 and the second resistor voltage divider circuit 200 according to the determined predetermined phase difference and the phase difference between the three-phase voltage signals. In an embodiment of the utility model, the first phase voltage signal, the second phase voltage signal and the third phase voltage signal can each differ in phase by 120 degrees, that is, the phase of the first phase voltage signal differs by 120 degrees from the phase of the second phase voltage signal, the phase of the first phase voltage signal differs by 120 degrees from the phase of the third phase voltage signal, and the phase of the second phase voltage signal differs by 120 degrees from the phase of the third phase voltage signal. The predetermined phase difference value may be 90 degrees, that is, the phase of the first differential signal and the phase of the second differential signal differ by 90 degrees.

[0063] The first resistor voltage divider circuit 100 is connected to the first phase voltage signal and the second phase voltage signal, and is used to divide the first phase voltage signal and the second phase voltage signal; it should be noted that the first resistor R1 voltage divider includes a resistor voltage divider circuit, and the first input end for connecting the first phase voltage signal and the second input end for connecting the second phase voltage signal are located at different positions of the resistor voltage divider circuit; since the first phase voltage signal and the second phase voltage signal have different phases, the voltage signal at other positions of the resistor voltage divider circuit can be obtained by performing related vector operations on the first phase voltage signal and the second phase voltage signal; it should be noted that the phase of the voltage obtained after the vector operation is related to the phase of the first phase voltage signal, the phase of the second phase voltage and the position in the resistor voltage divider circuit. In particular, when the phase of the first phase voltage signal differs from the phase of the second phase voltage by 0 degrees or 180 degrees, the phase of the voltage obtained after the vector operation is the same as or opposite to the phase of the first phase voltage.

[0064] Reference Figure 2In one embodiment of the utility model, the first resistor voltage divider circuit 100 includes a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4. The first end of the first resistor R1 is connected to the first phase voltage signal, and the second end is connected to the first end of the second resistor R2; the second end of the second resistor R2 is connected to the first end of the third resistor R3; the second end of the third resistor R3 is connected to the second end of the fourth resistor R4; the first end of the fourth resistor R4 is connected to the second phase voltage signal. The first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 constitute a resistor voltage divider circuit, wherein the first end of the first resistor R1 and the first end of the fourth resistor R4 are respectively connected to the first phase voltage signal and the second phase voltage signal; for other terminal positions in the resistor voltage divider circuit, for example: the second end of the first resistor R1, the second end of the second resistor R2 and the second end of the third resistor R3. The voltage at the selected terminal is related to the following factors: the first phase voltage signal, the second phase voltage signal and the resistance distribution of the resistor voltage divider circuit. In this embodiment, since the resistor voltage divider circuit is a linear system with homogeneity and superposition, the positions of other endpoints in the resistor voltage divider circuit can be used to calculate the first voltage under the first phase voltage signal and the second voltage under the second phase voltage signal, respectively; then the first voltage and the second voltage are vector-summed to obtain the voltage of the endpoint under the first phase voltage signal and the second phase voltage signal. For example, the voltage at the second end of the first resistor R1 is The voltage at the second end of the second resistor R2 is The voltage at the second end of the third resistor R3 is Among them, U represents the first phase voltage signal, V represents the second phase voltage signal; the first phase voltage signal and the second phase voltage signal are vectors. Three endpoints are selected in the resistor voltage divider circuit, and they are respectively used as the voltage output end, the first output end and the second output end of the first resistor voltage divider circuit 100. The first differential signal is the vector difference between the first output end and the second output end. In particular, the second end of the first resistor R1 can be selected as the first output end, the second end of the second resistor R2 can be selected as the voltage output end, and the second end of the third resistor R3 can be selected as the second output end; the first differential signal is It should be noted that, in this embodiment, four resistors are selected to illustrate the process of the resistor divider circuit dividing the first phase voltage signal and the second phase voltage signal; it does not mean that only four resistors can be used to form the resistor divider circuit. In other embodiments of the utility model, the resistor divider circuit may include three resistors, five resistors, six resistors or other numbers of resistors; it is only necessary to be able to select three endpoints in the resistor divider circuit, and the voltage values ​​of the three endpoints are respectively the vector sum of the algebraic expression corresponding to the first phase voltage signal and the algebraic expression corresponding to the second phase voltage signal. In addition, in this embodiment, the endpoint selected by the voltage output terminal can be the same as the endpoint selected by the first output terminal or the endpoint selected by the second output terminal, but the endpoint selected by the first output terminal is different from that selected by the second output terminal.

[0065] The second resistor voltage divider circuit 200 includes a resistor voltage divider circuit, which is used to output a second differential signal after voltage division processing of the first voltage and the third phase voltage signal. The second differential signal is related to the resistance distribution of the resistor voltage divider circuit in the second resistor voltage divider circuit 200, the position of the third output terminal and the second output terminal of the second resistor voltage divider circuit 200 in the resistor voltage divider circuit, the third phase voltage signal and the first voltage. Among them, the first voltage is related to the first resistor voltage divider circuit 100, the first phase voltage signal and the second phase voltage signal. Referring to the above embodiment, the phase of the second differential signal is related to the first phase voltage signal, the second phase voltage signal, the third phase voltage signal, the resistance in the first resistor voltage divider circuit 100, and the resistance in the second resistor voltage divider circuit 200; when the first phase voltage signal, the second phase voltage signal, and the third phase voltage signal do not change, the resistance composition of the first resistor voltage divider circuit 100 and the resistance composition of the second resistor voltage divider circuit 200 can be selected to achieve the goal that the difference between the phase of the second differential signal and the phase of the first differential signal is the predetermined phase difference. Specifically, the resistance values ​​of the first resistor R1 to the fourth resistor R4 and the resistance values ​​of the resistors in the second resistor voltage divider circuit 200 in the above embodiment are selected so that the difference between the phase of the second differential signal and the phase of the first differential signal is the predetermined phase difference. In particular, when the first phase voltage signal, the second phase voltage signal and the third phase voltage signal can differ in phase by 120 degrees, the resistance values ​​of the resistors in the first resistor voltage divider circuit 100 and the resistance values ​​of the resistors in the second resistor voltage divider circuit 200 are selected so that the phase of the first differential signal and the phase of the second differential signal differ by 90 degrees.

[0066] Reference Figure 3In one embodiment of the utility model, the second resistor voltage divider circuit 200 includes a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7. The second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6; the second end of the sixth resistor R6 is connected to the second end of the seventh resistor R7; the first end of the seventh resistor R7 is connected to the voltage output end of the first resistor voltage divider circuit 100; wherein the first end of the fifth resistor R5 is connected to the third phase voltage signal, and the first end of the seventh resistor R7 is connected to the first voltage. For other end positions in the second resistor voltage divider circuit 200, for example: the second end of the fifth resistor R5 and the second end of the sixth resistor R6. The voltages at the other end positions are related to the first voltage, the third phase voltage, the resistance values ​​of the fifth resistor R5, the sixth resistor R6 and the seventh resistor R7; it should be noted that the value of the first voltage is related to the first resistor voltage divider circuit 100, the first phase voltage signal and the second phase voltage signal. In this embodiment, the second end of the fifth resistor R5 and the second end of the sixth resistor R6 can be selected as the third output end of the second resistor voltage divider circuit 200 and the fourth output end of the second resistor voltage divider circuit 200, respectively. Because the resistor voltage divider circuit in the second resistor voltage divider circuit 200 is a linear system, it satisfies homogeneity and superposition; the voltage at the first output end is The voltage at the second output terminal is The voltage of the second differential signal is Wherein, W represents the third phase voltage signal, and Z represents the first voltage. It should be noted that, in this embodiment, three resistors are selected to illustrate the process of the resistor divider circuit in the second resistor divider circuit 200 dividing the first voltage and the third phase voltage signal; it does not mean that only three resistors can be used to form the resistor divider circuit. In other embodiments of the utility model, the resistor divider circuit may include four resistors, five resistors, six resistors or other numbers of resistors; it is only necessary to be able to select two endpoints in the resistor divider circuit, and the voltage values ​​of the two endpoints are respectively the vector differences of the algebraic expression corresponding to the first voltage and the algebraic expression corresponding to the third phase voltage signal.

[0067] It can be seen from the above embodiment that the phase difference between the phase of the first voltage and the phase of the first differential signal is related to the resistance distribution of the resistance divider circuit in the first resistance divider circuit 100, and the phase of the second differential signal is related to the first voltage, the third phase voltage signal and the resistance distribution in the second resistance divider circuit 200; therefore, the phase of the second differential signal and the phase of the first differential signal are related to the first phase voltage signal, the second phase voltage signal, the third phase voltage signal, the resistance distribution in the first resistance divider circuit 100 and the resistance distribution in the second resistance divider circuit 200. When the phase relationship between the first phase voltage signal, the second phase voltage signal and the third phase voltage signal is determined, the resistance distribution in the first resistance divider circuit 100 and the resistance distribution in the second resistance divider circuit 200 can be changed so that the phase difference between the phase of the first differential signal and the phase of the second differential signal is the predetermined phase difference. It should be noted that the resistance distribution is related to the voltage at each endpoint of the resistance divider circuit. Specifically, the resistance distribution in the first resistance divider circuit 100 affects the voltage expression of the endpoint, the algebraic expression before the first phase voltage signal and the algebraic expression before the second phase voltage signal; the resistance distribution in the second resistance divider circuit 200 affects the voltage expression of the endpoint, the algebraic expression before the first voltage and the algebraic expression before the third phase voltage signal.

[0068] It should be noted that the signal conversion circuit proposed in the present invention uses a hardware circuit to complete the conversion of a three-phase signal into a two-phase signal.

[0069] The utility model proposes a signal conversion circuit; the circuit comprises: a first resistor voltage divider circuit 100, the first resistor voltage divider circuit 100 has a first input terminal for receiving a first phase voltage signal, the first resistor voltage divider circuit 100 has a second input terminal for receiving a second phase voltage signal, the first resistor voltage divider circuit 100 also has a voltage output terminal, a first output terminal and a second output terminal; the first resistor voltage divider circuit 100 is used to divide the first phase voltage signal and the second phase voltage signal and output a first voltage through the voltage output terminal, and output a first voltage through the first output terminal of the first resistor voltage divider circuit 100 and the first resistor The second output end of the voltage divider circuit 100 outputs a first differential signal; the second resistor voltage divider circuit 200, the second resistor voltage divider circuit 200 has a first input end for accessing a third phase voltage signal, the second end of the second resistor voltage divider circuit 200 is connected to the voltage output end of the first resistor voltage divider circuit 100, and the second resistor voltage divider circuit 200 also has a first output end and a second output end; the second resistor voltage divider circuit 200 is used to divide the first voltage and the third phase voltage signal, and then output a second differential signal through the third output end of the second resistor voltage divider circuit 200 and the fourth output end of the second resistor voltage divider circuit 200. The utility model outputs a first differential signal and a second differential signal after voltage division processing of the first phase voltage signal, the second phase voltage signal and the third phase voltage signal through the first resistor voltage divider circuit 100 and the second resistor voltage divider circuit 200; and adjusts the phase difference between the first differential signal and the second differential signal by adjusting the resistance distribution of the first resistor voltage divider circuit 100 and the second resistor voltage divider circuit 200.

[0070] Reference Figure 2 In one embodiment of the present utility model, the first resistor voltage divider circuit 100 includes:

[0071] A first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4;

[0072] The first end of the first resistor R1 is connected to the first phase voltage signal, and the second end is connected to the first end of the second resistor R2; the second end of the second resistor R2 is connected to the first end of the third resistor R3; the second end of the third resistor R3 is connected to the second end of the fourth resistor R4; the first end of the fourth resistor R4 is connected to the second phase voltage signal;

[0073] Among them, the second end of the first resistor R1 is the first output end of the first resistor voltage divider circuit 100, the second end of the fourth resistor R4 is the second output end of the first resistor voltage divider circuit 100; the second end of the second resistor R2 is the voltage output end of the first resistor voltage divider circuit 100.

[0074] In this embodiment, the voltage divider circuit composed of the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 divides the first phase voltage signal and the second phase voltage signal to output a first voltage and a first differential signal; and in this embodiment, the second end of the first resistor R1 is the first output end of the first resistor voltage divider circuit 100, the second end of the fourth resistor R4 is the second output end of the first resistor voltage divider circuit 100; the second end of the second resistor R2 is the voltage output end of the first resistor voltage divider circuit 100. Referring to the above embodiment, the voltage at the voltage output end is The voltage at the first output terminal is The voltage at the second output terminal is The first differential signal output by the first output terminal and the second output terminal is Wherein, U represents the first phase voltage signal, and V represents the second phase voltage signal.

[0075] Reference Figure 3 In one embodiment of the present utility model, the second resistor voltage divider circuit 200 includes a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7;

[0076] The first end of the fifth resistor R5 is connected to the third phase voltage signal, and the second end is connected to the first end of the sixth resistor R6; the second end of the sixth resistor R6 is connected to the second end of the seventh resistor R7; the first end of the seventh resistor R7 is connected to the voltage output end of the first resistor voltage divider circuit 100;

[0077] Among them, the first end of the seventh resistor R7 is the second end of the second resistor voltage divider circuit 200; the second end of the fifth resistor R5 is the third output end of the second resistor voltage divider circuit 200, and the second end of the seventh resistor R7 is the fourth output end of the second resistor voltage divider circuit 200.

[0078] In this embodiment, the resistor voltage divider circuit composed of the fifth resistor R5, the sixth resistor R6 and the seventh resistor R7 divides the first voltage and the third phase voltage signal to output a second differential signal; and in this embodiment, the second end of the fifth resistor R5 is the third output end of the second resistor voltage divider circuit 200, and the second end of the seventh resistor R7 is the fourth output end of the second resistor voltage divider circuit 200. Referring to the above embodiment, the voltage of the first output end is The voltage at the second output terminal is The voltage of the second differential signal is Wherein, W represents the third phase voltage signal, and Z represents the first voltage.

[0079] In one embodiment of the present invention, the signal conversion circuit further includes:

[0080] The isolation circuit 300 has an input end connected to the voltage output end of the first resistor divider circuit 100 and an output end connected to the second end of the second resistor divider circuit 200 ; the isolation circuit 300 is used to isolate and output the first voltage to the second resistor divider circuit 200 .

[0081] In this embodiment, in order to avoid mutual interference between the first resistor voltage divider circuit 100 and the second resistor voltage divider circuit 200, an isolation circuit 300 is provided between the voltage output end of the first resistor voltage divider circuit 100 and the second end of the second resistor voltage divider circuit 200; the isolation circuit 300 is used to isolate the first resistor voltage divider circuit 100 from the second resistor voltage divider circuit 200; and to isolate and output the first voltage to the second resistor voltage divider circuit 200, so that the second resistor voltage divider circuit 200 does not affect the potential of each resistor end point in the first resistor voltage divider circuit 100. The isolation circuit 300 may include: a voltage follower VF1, an optocoupler circuit, a magnetic coupling circuit, or a capacitive isolation circuit, etc.

[0082] In an embodiment of the present invention, the isolation circuit 300 includes:

[0083] A voltage follower VF1 , wherein the positive input terminal of the voltage follower VF1 is connected to the voltage output terminal of the first resistor voltage divider circuit 100 , and the output terminal and the negative input terminal of the voltage follower VF1 are connected to the second terminal of the second resistor voltage divider circuit 200 .

[0084] In the above embodiments, the three-phase signal is a three-phase voltage signal, but in actual application, there is a situation where the three-phase signal is a three-phase current signal; when the three-phase signal is a three-phase current signal, preprocessing is required to convert the three-phase current signal into a corresponding three-phase voltage signal.

[0085] Reference Figure 4 In one embodiment of the present utility model, the signal conversion circuit further includes:

[0086] A first phase current signal access terminal 500 is used to access a first phase current signal;

[0087] The second phase current signal access terminal 600 is used to access the second phase current signal;

[0088] The third phase current signal access terminal 700 is used to access the third phase current signal;

[0089] A preprocessing circuit 400, wherein a first input terminal of the preprocessing circuit 400 is connected to the first phase current signal access terminal 500, a second input terminal is connected to the second phase current signal access terminal 600, and a third input terminal is connected to the third phase current signal access terminal 700; a first output terminal of the preprocessing circuit 400 is connected to a first input terminal of the first resistor voltage divider circuit 100, a second output terminal of the preprocessing circuit 400 is connected to a second input terminal of the first resistor voltage divider circuit 100, and a third output terminal of the preprocessing circuit 400 is connected to a first input terminal of the second resistor voltage divider circuit 200;

[0090] The preprocessing circuit 400 is used to convert the first phase current signal into a first phase voltage signal and output it to the first input end of the first resistor divider circuit 100, and to convert the second phase current signal into a second phase voltage signal and output it to the second input end of the first resistor divider circuit 100; the preprocessing circuit 400 is also used to convert the third phase current signal into a third phase voltage signal and output it to the first input end of the second resistor divider circuit 200.

[0091] In this embodiment, the preprocessing circuit 400 converts the first phase current signal, the second phase current signal and the third phase current signal into a first phase voltage signal, a second phase voltage signal and a third phase voltage signal respectively; the preprocessing circuit 400 outputs the first phase voltage signal to the first input end of the first resistor voltage divider circuit 100, and outputs the second phase voltage signal to the second input end of the first resistor voltage divider circuit 100, and also outputs the third phase voltage signal to the first input end of the second resistor voltage divider circuit 200. The preprocessing circuit 400 may include a current signal conversion voltage signal circuit, and the current signal conversion voltage signal circuit is used to convert the three-phase current signal into a three-phase voltage signal.

[0092] The preprocessing circuit 400 may include a resistor voltage divider circuit and a voltage follower VF1. When current passes through the resistor voltage divider circuit, different potentials are generated at the endpoints of each resistor. The input end of the voltage follower VF1 may be connected to one endpoint of the resistor voltage divider circuit, and the output end is connected to the first resistor voltage divider circuit 100 or the second resistor voltage divider circuit 200. The voltage follower VF1 is used to output the voltage at the endpoint to the first resistor voltage divider circuit 100 or the second resistor voltage divider circuit 200. Three groups of resistor voltage divider circuits and voltage followers VF1 may be used to convert a three-phase current signal into a three-phase voltage signal.

[0093] The pre-processing circuit 400 may further include a transimpedance amplifier, which may convert the current signal into a voltage signal; three groups of transimpedance amplifiers may be used to convert the three-phase current signal into a three-phase voltage signal.

[0094] The pre-processing circuit 400 may further include a transistor, using a current-type device transistor to control the output voltage value through current; three groups of transistors may be used to convert a three-phase current signal into a three-phase voltage signal.

[0095] Reference Figure 5 In one embodiment of the present utility model, the preprocessing circuit 400 includes:

[0096] A first bias voltage access terminal 440, used for accessing a first bias voltage;

[0097] The second bias voltage access terminal 450 is used to access the second bias voltage;

[0098] A first signal conversion circuit 410, wherein a first input terminal is connected to the first bias voltage access terminal 440, a second input terminal is connected to the second bias voltage access terminal 450, and a third input terminal is connected to the first phase current signal access terminal 500; the first signal conversion circuit 410 is used to convert the first phase current signal into the first phase voltage signal according to the first bias voltage and the second bias voltage, and then output the converted signal to the first input terminal of the first resistor voltage divider circuit 100;

[0099] A second signal conversion circuit 420, wherein the first input terminal is connected to the first bias voltage access terminal 440, the second input terminal is connected to the second bias voltage access terminal 450, and the third input terminal is connected to the second phase current signal access terminal 600; the second signal conversion circuit 420 is used to convert the second phase current signal into the second phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the second input terminal of the first resistor divider circuit 100;

[0100] The third signal conversion circuit 430 has a first input terminal connected to the first bias voltage access terminal 440, a second input terminal connected to the second bias voltage access terminal 450, and a third input terminal connected to the third phase current signal access terminal 700; the third signal conversion circuit 430 is used to convert the third phase current signal into the third phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the first input terminal of the second resistor divider circuit 200.

[0101] In this embodiment, the preprocessing circuit 400 includes three signal conversion circuits, and the signal conversion circuit includes a transimpedance amplifier circuit; the circuit structures of the first signal conversion circuit 410, the second signal conversion circuit 420 and the third signal conversion circuit 430 are consistent;

[0102] Reference Figure 6 , the first signal conversion circuit 410 is used to convert the first phase current signal into the first phase voltage signal and then output it to the first input end of the first resistance voltage divider circuit 100;

[0103] The first signal conversion circuit 410 includes: an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and a first operational amplifier U1;

[0104] The first end of the tenth resistor R10 is connected to the second bias voltage access terminal 450, and the second end is connected to the positive input terminal of the first operational amplifier U1; the negative input terminal of the first operational amplifier U1 is connected to the first phase current signal access terminal 500; the first end of the eighth resistor R8 is connected to the first bias voltage access terminal 440, and the second end is connected to the first end of the ninth resistor R9 and the negative input terminal of the first operational amplifier U1; the second end of the ninth resistor R9 is connected to the first input terminal of the first resistor voltage divider circuit 100.

[0105] The second signal conversion circuit 420 includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13 and a second operational amplifier U2;

[0106] The first end of the thirteenth resistor R13 is connected to the second bias voltage access terminal 450, and the second end is connected to the positive input terminal of the second operational amplifier U2; the negative input terminal of the second operational amplifier U2 is connected to the second phase current access terminal; the first end of the eleventh resistor R11 is connected to the first bias voltage access terminal 440, and the second end is connected to the first end of the twelfth resistor R12 and the negative input terminal of the second operational amplifier U2; the second end of the twelfth resistor R12 is connected to the second end of the first resistor voltage divider circuit 100;

[0107] The third signal conversion circuit 430 includes:

[0108] A fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16 and a third operational amplifier U3;

[0109] The first end of the sixteenth resistor R16 is connected to the second bias voltage access terminal 450, and the second end is connected to the positive input terminal of the third operational amplifier U3; the negative input terminal of the third operational amplifier U3 is connected to the third phase current access terminal; the first end of the fourteenth resistor R14 is connected to the first bias voltage access terminal 440, and the second end is connected to the first end of the fifteenth resistor R15 and the negative input terminal of the third operational amplifier U3; the second end of the fifteenth resistor R15 is connected to the first end of the second resistor voltage divider circuit 200.

[0110] Since the circuit structures of the first signal conversion circuit 410 , the second signal conversion circuit 420 and the third signal conversion circuit 430 are the same, only the first signal conversion circuit 410 is described here, and the other signal conversion circuits also have the same properties.

[0111] Due to the virtual short and virtual open properties of the first operational amplifier U1, the potential of the negative input terminal of the first operational amplifier U1 is equal to the potential of its positive input terminal, and the value of the voltage at the positive input terminal is equal to the value of the second bias voltage; the second end of the eighth resistor R8 is analyzed, the first phase current signal flows into this end point, and the current flowing through the eighth resistor R8 at the first bias voltage access terminal 440 also flows into this end point. According to Kirchhoff's current law, the magnitude of the current flowing through the ninth resistor R9 is The voltage at the second end of the ninth resistor R9, that is, the first phase voltage is Among them, I R9 is the current flowing through the ninth resistor R9, I U is the first phase current, U1 is the first bias voltage, and U2 is the second bias voltage. The first bias voltage may be 5V, and the second bias voltage may be 3.8V.

[0112] Due to the virtual short and virtual open properties of the second operational amplifier U2, the potential of the negative input terminal of the second operational amplifier U2 is equal to the potential of its positive input terminal, and the voltage value of the positive input terminal is equal to the value of the second bias voltage; the second end of the eleventh resistor R11 is analyzed, the second phase current signal flows into this end point, and the current flowing through the eleventh resistor R11 at the first bias voltage access terminal 440 also flows into this end point. According to Kirchhoff's current law, the magnitude of the current flowing through the twelfth resistor R12 is The voltage at the second end of the twelfth resistor R12, i.e., the second phase voltage is Among them, I R12 is the current flowing through the twelfth resistor R12, I V is the second phase current, U1 is the first bias voltage, and U2 is the second bias voltage.

[0113] Due to the virtual short and virtual open properties of the third operational amplifier U3, the potential of the negative input terminal of the third operational amplifier U3 is equal to the potential of its positive input terminal, and the value of the voltage at the positive input terminal is equal to the value of the second bias voltage; the second end of the fourteenth resistor R14 is analyzed, the third phase current signal flows into this end point, and the current flowing through the fourteenth resistor R14 at the first bias voltage access terminal 440 also flows into this end point. According to Kirchhoff's current law, the magnitude of the current flowing through the fifteenth resistor R15 is The voltage at the second end of the twelfth resistor R12, i.e., the second phase voltage is Among them, I R15 is the current flowing through the twelfth resistor R12, I W is the second phase current, U1 is the first bias voltage, and U2 is the second bias voltage.

[0114] In the above embodiment, the first differential signal and the second differential signal are voltage signals, which are not conducive to long-distance transmission.

[0115] In an embodiment of the present utility model, the first resistor voltage divider circuit 100 further includes:

[0116] a seventeenth resistor R17 and an eighteenth resistor R18;

[0117] A first end of the seventeenth resistor R17 is connected to the second end of the first resistor R1 , and a first end of the eighteenth resistor R18 is connected to the second end of the third resistor R3 .

[0118] The second resistor voltage divider circuit 200 further includes:

[0119] a nineteenth resistor R19 and a twentieth resistor R20;

[0120] A first end of the nineteenth resistor R19 is connected to the second end of the fifth resistor R5 , and a first end of the twentieth resistor R20 is connected to the second end of the sixth resistor R6 .

[0121] The seventeenth resistor R17 and the eighteenth resistor R18 convert the first differential signal from a voltage form to a current form, and the nineteenth resistor R19 and the twentieth resistor R20 convert the second differential signal from a voltage form to a current form.

[0122] The present invention further provides a sensor, the sensor comprising the signal conversion circuit. The specific structure of the signal conversion circuit refers to the above embodiment. Since the sensor adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0123] The above description is only an optional embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A signal conversion circuit, characterized in that: The circuit comprises: A first resistor voltage divider circuit, wherein the first resistor voltage divider circuit has a first input terminal for receiving a first phase voltage signal, the first resistor voltage divider circuit has a second input terminal for receiving a second phase voltage signal, and the first resistor voltage divider circuit further has a voltage output terminal, a first output terminal, and a second output terminal; The first resistor voltage divider circuit is used to output a first voltage through the voltage output terminal after voltage division processing of the first phase voltage signal and the second phase voltage signal, and to output a first differential signal through the first output terminal of the first resistor voltage divider circuit and the second output terminal of the first resistor voltage divider circuit; a second resistor voltage divider circuit, wherein the second resistor voltage divider circuit has a first input terminal for receiving a third phase voltage signal, a second terminal of the second resistor voltage divider circuit is connected to a voltage output terminal of the first resistor voltage divider circuit, and the second resistor voltage divider circuit further has a third output terminal and a fourth output terminal; The second resistor voltage divider circuit is used to divide the first voltage and the third phase voltage signal and then output a second differential signal through the third output terminal of the second resistor voltage divider circuit and the fourth output terminal of the second resistor voltage divider circuit.

2. The signal conversion circuit according to claim 1, characterized in that: The first resistor voltage divider circuit comprises: a first resistor, a second resistor, a third resistor, and a fourth resistor; The first end of the first resistor is connected to the first phase voltage signal, and the second end is connected to the first end of the second resistor; the second end of the second resistor is connected to the first end of the third resistor; the second end of the third resistor is connected to the second end of the fourth resistor; the first end of the fourth resistor is connected to the second phase voltage signal; Among them, the second end of the first resistor is the first output end of the first resistor voltage divider circuit, the second end of the fourth resistor is the second output end of the first resistor voltage divider circuit; the second end of the second resistor is the voltage output end of the first resistor voltage divider circuit.

3. The signal conversion circuit according to claim 1, characterized in that: The second resistor voltage divider circuit comprises: a fifth resistor, a sixth resistor and a seventh resistor; The first end of the fifth resistor is connected to the third phase voltage signal, and the second end is connected to the first end of the sixth resistor; the second end of the sixth resistor is connected to the second end of the seventh resistor; the first end of the seventh resistor is connected to the voltage output end of the first resistor voltage divider circuit; Among them, the first end of the seventh resistor is the second end of the second resistor voltage divider circuit; the second end of the fifth resistor is the third output end of the second resistor voltage divider circuit, and the second end of the seventh resistor is the fourth output end of the second resistor voltage divider circuit.

4. The signal conversion circuit according to any one of claims 1 to 3, characterized in that: The circuit further comprises: An isolation circuit, whose input end is connected to the voltage output end of the first resistor voltage divider circuit, and whose output end is connected to the second end of the second resistor voltage divider circuit; the isolation circuit is used to isolate and output the first voltage to the second resistor voltage divider circuit.

5. The signal conversion circuit according to claim 4, characterized in that: The isolation circuit comprises: A voltage follower, wherein the positive input terminal of the voltage follower is connected to the voltage output terminal of the first resistor voltage divider circuit, and the output terminal and the negative input terminal of the voltage follower are connected to the second terminal of the second resistor voltage divider circuit.

6. The signal conversion circuit according to any one of claims 1 to 3, characterized in that: The signal conversion circuit also includes: A first phase current signal access terminal, used for accessing a first phase current signal; A second phase current signal access terminal, used for accessing a second phase current signal; A third-phase current signal access terminal, used for accessing a third-phase current signal; a preprocessing circuit, wherein a first input terminal of the preprocessing circuit is connected to the first phase current signal access terminal, a second input terminal is connected to the second phase current signal access terminal, and a third input terminal is connected to the third phase current signal access terminal; a first output terminal of the preprocessing circuit is connected to the first input terminal of the first resistor voltage divider circuit, a second output terminal of the preprocessing circuit is connected to the second input terminal of the first resistor voltage divider circuit, and a third output terminal of the preprocessing circuit is connected to the first input terminal of the second resistor voltage divider circuit; The preprocessing circuit is used to convert the first phase current signal into a first phase voltage signal and output it to the first input end of the first resistor divider circuit, and to convert the second phase current signal into a second phase voltage signal and output it to the second input end of the first resistor divider circuit; the preprocessing circuit is also used to convert the third phase current signal into a third phase voltage signal and output it to the first input end of the second resistor divider circuit.

7. The signal conversion circuit according to claim 6, characterized in that: The preprocessing circuit comprises: A first bias voltage access terminal, used for accessing a first bias voltage; A second bias voltage access terminal, used for accessing a second bias voltage; a first signal conversion circuit, wherein the first input terminal is connected to the first bias voltage access terminal, the second input terminal is connected to the second bias voltage access terminal, and the third input terminal is connected to the first phase current signal access terminal; the first signal conversion circuit is used to convert the first phase current signal into the first phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the first input terminal of the first resistor divider circuit; a second signal conversion circuit, wherein a first input terminal is connected to the first bias voltage access terminal, a second input terminal is connected to the second bias voltage access terminal, and a third input terminal is connected to the second phase current signal access terminal; the second signal conversion circuit is used to convert the second phase current signal into the second phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the second input terminal of the first resistor divider circuit; A third signal conversion circuit, wherein the first input terminal is connected to the first bias voltage access terminal, the second input terminal is connected to the second bias voltage access terminal, and the third input terminal is connected to the third phase current signal access terminal; the third signal conversion circuit is used to convert the third phase current signal into the third phase voltage signal according to the first bias voltage and the second bias voltage, and then output it to the first input terminal of the second resistance voltage divider circuit.

8. The signal conversion circuit according to claim 7, characterized in that: The first signal conversion circuit comprises: an eighth resistor, a ninth resistor, a tenth resistor and a first operational amplifier; The first end of the tenth resistor is connected to the second bias voltage access terminal, and the second end is connected to the positive input terminal of the first operational amplifier; the negative input terminal of the first operational amplifier is connected to the first phase current signal access terminal; the first end of the eighth resistor is connected to the first bias voltage access terminal, and the second end is connected to the first end of the ninth resistor and the negative input terminal of the first operational amplifier; the second end of the ninth resistor is connected to the first input terminal of the first resistor voltage divider circuit.

9. The signal conversion circuit according to claim 2, characterized in that: The first resistor voltage divider circuit further includes: a seventeenth resistor and an eighteenth resistor; The first end of the seventeenth resistor is connected to the second end of the first resistor, and the first end of the eighteenth resistor is connected to the second end of the third resistor.

10. A sensor, characterized in that: The sensor comprises a signal conversion circuit as described in any one of claims 1-9.

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