Incremental encoder level conversion module

Abstract

The utility model discloses a level conversion module of an incremental encoder, which belongs to the technical field of circuit design, and adopts the technical scheme that the level conversion module comprises an encoder, a 24V input power supply, a 5V differential to single-ended circuit module, a driving optocoupler circuit module, a single-ended to 24V differential signal circuit module, a first 24V to 5V circuit and a second 24V to 5V circuit. A 5V differential signal of the encoder is received, a 24V differential signal is output after conversion, driving and secondary conversion, and meanwhile, a 24V-to-5V circuit is used for supplying power to each component. The beneficial effects are that 5V differential signals output by the incremental encoder are converted into 24V differential signals, so that transmission signals can be stably and reliably transmitted in a long distance, and the anti-interference capability of the transmission signals is enhanced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of circuit design, specifically related to a incremental encoder level conversion module. BACKGROUND

[0002] The development of motor control technology can be traced back to the end of the 19th century, with the widespread application of electricity, the motor gradually became an indispensable equipment in industrial production. In the development process of motor control technology, people are constantly exploring more efficient and accurate control methods. Double-fed wind power control system as an important application field of motor control technology, has also experienced continuous development and improvement.

[0003] In the motor control system, the stability and accuracy of signal transmission are crucial. Especially in long-distance transmission or high-speed conditions, signal attenuation and interference problems are increasingly prominent. In order to solve these problems, people began to explore level conversion technology to convert low-level signals into high-level signals, thereby enhancing the anti-interference ability and transmission distance of the signal.

[0004] Incremental encoder is a commonly used sensor device, which can convert the speed and position information of the motor into electrical signal output. With the continuous development of industrial automation technology, incremental encoder is increasingly widely used in motor control systems. Especially in double-fed wind power control system, incremental encoder is used to accurately measure the speed and rotor position, providing important technical support for realizing high-performance control.

[0005] In traditional level conversion modules, people usually use simple resistance voltage division or amplification circuit to realize level conversion. However, these methods have many shortcomings, such as large signal attenuation, poor anti-interference ability, etc. In order to solve these problems, people began to develop more advanced level conversion modules.

[0006] The Chinese patent with publication number CN218679031U discloses an encoder signal level conversion circuit. Although this patent also involves signal conversion, it is mainly used for multi-channel level conversion circuit to realize communication between devices driven by different voltages, and the converted TTL signal does not have significant improvement in anti-interference ability and transmission distance. UTILITY MODEL CONTENT

[0007] In order to solve the problem of instability of 5V differential transmission signal under the condition of high speed and long distance transmission of existing traditional motor. The utility model provides a kind of incremental encoder level conversion module, converts the 5V differential signal output by incremental encoder into 24V differential signal, so that transmission signal can be stably and reliably transmitted at long distance, and the anti-interference ability of transmission signal is enhanced.

[0008] To achieve the above object, the technical scheme of the utility model is as follows:

[0009] A kind of incremental encoder level conversion module, including encoder, 24V input power supply, 5V difference single-ended circuit module, driving optical coupling circuit module, single-ended 24V difference signal circuit module, first 24V-5V circuit and second 24V-5V circuit, 5V difference signal of encoder output is connected 5V difference single-ended circuit module by input connector, the 5V difference single-ended circuit module is connected driving optical coupling circuit module, the driving optical coupling circuit module is connected single-ended 24V difference signal circuit module, 24V difference signal is output by output connector of the single-ended 24V difference signal circuit module, the 24V input power supply is connected single-ended 24V difference signal circuit module, 24V input power supply is connected driving optical coupling circuit module by first 24V-5V circuit, 24V input power supply is connected encoder, 5V difference single-ended circuit module and driving optical coupling circuit module by second 24V-5V circuit.

[0010] Further, the 5V difference single-ended circuit module adopts differential signal processing chip with model AM26LS32.

[0011] Further, the driving optical coupling circuit module adopts isolated optical coupler and Schmidt positive logic chip with model SN74AHC1G04.

[0012] Further, the single-ended 24V difference signal circuit module adopts driver with model OL7272.

[0013] Further, the first 24V-5V circuit adopts power module with model K7805.

[0014] Further, the second 24V-5V circuit adopts power module with model WRB2405ZP-3WR2.

[0015] The utility model has the advantages that:

[0016] 1, enhance signal transmission distance: by converting the 5V difference signal output by incremental encoder into 24V difference signal, the signal can be stably transmitted over a longer distance, solving the problem of 5V difference transmission signal instability under the condition of motor high speed and long distance transmission.

[0017] 2, improve signal anti-interference ability: the stability of differential signal transmission and the anti-interference of isolated optical coupler are used to effectively reduce the influence of external interference on signal transmission.

[0018] 3, improve system reliability: the level conversion module can stably transmit signals, reducing system failure caused by signal interference or unstable transmission. Attached Figure Description

[0019] Figure 1 This is a block diagram of the encoder level conversion module of this utility model;

[0020] Figure 2 This is a schematic diagram of the encoder level conversion module of this utility model;

[0021] The attached figures are labeled as follows:

[0022] 1. Encoder; 2. 24V input power supply; 3. 5V differential to single-ended circuit module; 4. Drive optocoupler circuit module; 5. Single-ended to 24V differential signal circuit module; 6. First 24V to 5V circuit; 7. Second 24V to 5V circuit. Detailed Implementation

[0023] Example 1

[0024] An incremental encoder level conversion module includes an encoder 1, a 24V input power supply 2, a 5V differential-to-single-ended circuit module 3, a drive optocoupler circuit module 4, a single-ended to 24V differential signal circuit module 5, a first 24V to 5V circuit 6, and a second 24V to 5V circuit 7. The 5V differential signal output by the encoder 1 is connected to the 5V differential-to-single-ended circuit module 3 via an input connector. The 5V differential-to-single-ended circuit module 3 is connected to the drive optocoupler circuit module 4. The drive optocoupler circuit module 4 is connected to the single-ended to 24V differential signal circuit module 5. The single-ended to 24V differential signal circuit module 5 outputs a 24V differential signal via an output connector. The 24V input power supply 2 is connected to the single-ended to 24V differential signal circuit module 5. The 24V input power supply 2 is connected to the drive optocoupler circuit module 4 via the first 24V to 5V circuit 6. The 24V input power supply 2 is connected to the encoder 1, the 5V differential-to-single-ended circuit module 3, and the drive optocoupler circuit module 4 via the second 24V to 5V circuit 7.

[0025] The 5V differential-to-single-ended circuit module 3 uses a differential signal processing chip of model AM26LS32.

[0026] The driving optocoupler circuit module 4 uses an isolation optocoupler and a Schmitt positive logic chip of model SN74AHC1G04.

[0027] The single-ended to 24V differential signal circuit module 5 uses a driver of model OL7272.

[0028] The first 24V to 5V circuit 6 uses a power module of model K7805.

[0029] The second 24V-to-5V circuit 7 adopts a power module with a model of WRB2405ZP-3WR2.

[0030] The following is a further description of the principle block diagram of the utility model:

[0031] The three pairs of differential signals A / B / Z are matched by terminal resistors and filtered, and then enter the differential signal processing chip. The chip for realizing 5V differential-to-single-ended signal function is AM26LS32, which is an RS422 interface integrated chip and can realize 4-way differential signal processing. The logic of this differential signal processing is that when the differential positive signal is greater than the differential negative signal, the output is high level, and vice versa. This positive logic processing circuit makes the chip output logic consistent with the differential positive signal logic, without the need for other logic processing. The power supply of AM26LS32 is 5V, and the voltage input of the entire level conversion module is 24V, so it is necessary to convert 24V to 5V power supply for AM26LS32 and incremental encoder power supply.

[0032] The signal after the differential processing chip is a 0-5V square wave signal, which has weak driving ability, and the signal current required by the isolation optocoupler driver is large, so a Schmitt positive logic chip is selected to be connected at the rear end of the differential processing chip to enhance the driving ability of the signal. The Schmitt positive logic chip can generate an 8-mA current when the signal is high at 5V, and the minimum driving current of the isolation optocoupler is only 3mA, which is sufficient to drive the optocoupler. The power supply of the Schmitt positive logic chip is 5V, which is the same as the power supply of the encoder.

[0033] The isolation optocoupler is an electrical signal isolator that plays a role in digital isolation and anti-interference. The logic of the optocoupler is positive, that is, when the input is high, the optocoupler is turned on and the output logic is high. Since the ground of the optocoupler is an isolated ground, a 24V-to-5V power supply is needed to power the optocoupler.

[0034] The single-ended-to-differential chip at the rear end of the optocoupler is OL7272, which is a four-way differential line driver that can convert the three signals A / B / Z into 24V differential signals. Similarly, the chip does not use the input pin ground. The feature of this chip is that it can run when the driving cable length exceeds 100 meters. The standard power supply of OL7272 is 24V, which is directly powered by the 24V power supply converted by the level conversion.

[0035] Currently, the vector control method is usually used in the control system of double-fed wind power generation, and the detection of speed and rotor position is the condition for realizing high-performance control. The incremental encoder plays an important role in such accurate measurement.

[0036] Incremental encoders utilize photoelectric conversion to output three sets of square wave pulses A, B, and Z. Differential drive incremental encoders output three-phase signals: A+ / A-, B+ / B-, and Z+ / Z-. This 5V differential signal offers stable transmission with minimal attenuation and strong anti-interference capabilities, making it suitable for long-distance transmission. As the detection speed increases, the pulse width of the output signal narrows. This level conversion module converts this 5V differential signal to a 24V differential signal, further enhancing anti-interference capabilities. When detecting high-speed incremental encoders and outputting narrow-pulse square wave pulses, these narrow pulses can be transmitted over even greater distances.

[0037] Example 2

[0038] This embodiment provides a detailed description of the circuit structure and connection relationships of this utility model in conjunction with the accompanying drawings.

[0039] like Figure 1 As shown, an incremental encoder level conversion module includes an encoder 1, a 24V input power supply 2, a 5V differential to single-ended circuit module 3, a drive optocoupler circuit module 4, a single-ended to 24V differential signal circuit module 5, a first 24V to 5V circuit 6, and a second 24V to 5V circuit 7. The 5V differential signal output by the encoder 1 is connected to the 5V differential to single-ended circuit module 3 through an input connector. The 5V differential to single-ended circuit module 3 is connected to the drive optocoupler circuit module 4. The drive optocoupler circuit module 4 is connected to the single-ended to 24V differential signal circuit module 5. The single-ended to 24V differential signal circuit module 5 outputs a 24V differential signal through an output connector. The 24V input power supply 2 is connected to the single-ended to 24V differential signal circuit module 5. The 24V input power supply 2 is connected to the drive optocoupler circuit module 4 through the first 24V to 5V circuit 6. The 24V input power supply 2 is connected to the encoder 1, the 5V differential to single-ended circuit module 3, and the drive optocoupler circuit module 4 through the second 24V to 5V circuit 7.

[0040] like Figure 2 As shown, the input connectors include J1 and J2; the output connectors include J3 and J4; the 5V differential to single-ended circuit includes U5; the driving optocoupler circuit includes U1, U2, U4, U6, U7, U8, U12, U14, and U15; the single-ended to 24V differential signal circuit includes U13; the first 24V to 5V circuit 6 includes U16; and the second 24V to 5V circuit 7 includes U10.

[0041] J1 includes pins 1 to 4; J3 includes pins 1 to 4; U5 is a differential signal processing chip of model AM26LS32, including pins 1 to 16; U1 is a Schmitt positive logic chip of model SN74AHC1G04, including pins 1 to 5; U2 is a Schmitt positive logic chip of model SN74AHC1G04, including pins 1 to 5; U4 is a Schmitt positive logic chip of model SN74AHC1G04, including pins 1 to 5; U6 is a Schmitt positive logic chip of model SN74AHC1G04, including pins 1 to 5; U7 is a Schmitt positive logic chip of model SN74AHC1G04. The chip includes pins 1 to 5; U8 is a Schmitt positive logic chip of model SN74AHC1G04, including pins 1 to 5; U12 is an isolation optocoupler, including pins 1, 3, 4, 5, and 6; U14 is an isolation optocoupler, including pins 1, 3, 4, 5, and 6; U15 is an isolation optocoupler, including pins 1, 3, 4, 5, and 6; U13 is a driver of model OL7272, including pins 1 to 16; U16 is a power module of model K7805, including pins 1 to 3; U10 is a power module of model WRB2405ZP-3WR2, including pins 2, 8, 9, 14, 16, 22, and 28.

[0042] Pins 22 and 28 of U10 are electrically connected in series with the positive terminal of a 68uF capacitor E1. Pins 2 and 8 are electrically connected in series with the negative terminal of a 68uF capacitor E1. A 100nF capacitor C21 is connected in parallel with the 68uF capacitor E1, with one end grounded and the other end electrically connected to the negative terminal of a STPS340 diode D12. The positive terminal of D12 is connected to a 24V input power supply 2. Pin 14 of U10 is connected in series with the positive terminal of a 100uF capacitor E2. Pin 16 is connected in series with the negative terminal of a 100uF capacitor E2. A 100uF capacitor C22 is connected in parallel with E2. A SMBJ6.0A diode D14 is connected in parallel with C22. The positive terminal of D14 is electrically connected to the positive terminal of E2, and the negative terminal of D14 is electrically connected to the test point TP1. The negative terminal of E2 is grounded, and the positive terminal outputs a 5V electrical signal +5VISO2.

[0043] Pin 1 of U16 is connected to a 24V input power supply 2 and is connected in series with one end of a 10uF capacitor C27. Pin 3 outputs a 5V electrical signal and is connected in series with one end of a 22uF capacitor C31. Pin 2 is grounded and connected in series with the other end of C27 and C31.

[0044] Pins 8, 9, 10, and 12 of U5 are grounded, pin 11 is not connected, pin 1 is electrically connected to pin 4 of J1, pin 2 is electrically connected to pin 3 of J1, pin 14 is electrically connected to pin 1 of J2, pin 15 is electrically connected to pin 2 of J2, pin 6 is electrically connected to pin 1 of J1, pin 7 is electrically connected to pin 2 of J1, pin 4 is connected to the 5V electrical signal +5VISO2 output by U10, and pin 16 is connected to the 5V electrical signal +5VISO2 output by U10 and connected in series with a 100nF capacitor C9 before being grounded.

[0045] Pin 3 of U5 is connected in series with a 1kΩ resistor R5 and then electrically connected to pin 2 of U1; pin 1 of U1 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C1 and then grounded, pin 4 is connected in series with a 1kΩ resistor R7 and then electrically connected to pin 2 of U2; pin 1 of U2 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C2 and then grounded, pin 4 outputs the ECB signal;

[0046] Pin 13 of U5 is connected in series with a 1kΩ resistor R11 and then electrically connected to pin 2 of U4; pin 1 of U4 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C7 and then grounded, pin 4 is connected in series with a 1kΩ resistor R12 and then electrically connected to pin 2 of U6; pin 1 of U6 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C8 and then grounded, pin 4 outputs the ECA signal;

[0047] Pin 5 of U5 is connected in series with a 1kΩ resistor R15 and then electrically connected to pin 2 of U7; pin 1 of U7 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C13 and then grounded, pin 4 is connected in series with a 1kΩ resistor R16 and then electrically connected to pin 2 of U8; pin 1 of U8 is not connected, pin 3 is grounded, pin 5 is connected to the 5V +5VISO2 output of U10 and connected in series with a 100nF capacitor C14 and then grounded, pin 4 outputs the ECZ signal;

[0048] Pin 1 of U12 is connected to the 5V electrical signal +5VISO2 output by U10. Pin 3 is connected in series with a resistor R34 with a resistance of 392 ohms and is electrically connected to pin 4 of U6. Pin 4 is grounded. Pin 5 is connected in series with a resistor R33 with a resistance of 10kΩ and is then connected to the 5V electrical signal 5V output by U16. One end of pin 6 is electrically connected to R33, and the other end is electrically connected to a 100nF capacitor C40 and then grounded.

[0049] Pin 1 of U14 is connected to the 5V electrical signal +5VISO2 output by U10. Pin 3 is connected in series with a resistor R43 with a resistance of 392 ohms and is electrically connected to pin 4 of U2. Pin 4 is grounded. Pin 5 is connected in series with a resistor R37 with a resistance of 10kΩ and is then connected to the 5V electrical signal 5V output by U16. One end of pin 6 is electrically connected to R37, and the other end is electrically connected to a 100nF capacitor C41 and then grounded.

[0050] Pin 1 of U15 is connected to the 5V electrical signal +5VISO2 output by U10. Pin 3 is connected in series with a resistor R48 with a resistance of 392 ohms and is electrically connected to pin 4 of U8. Pin 4 is grounded. Pin 5 is connected in series with a resistor R45 with a resistance of 10kΩ and is then connected to the 5V electrical signal 5V output by U16. One end of pin 6 is electrically connected to R45, and the other end is electrically connected to a 100nF capacitor C42 and then grounded.

[0051] Pin 1 of U13 is connected in series with resistor R39 (47 ohms) and then electrically connected to pin 5 of U12. Pin 7 is connected in series with resistor R40 (47 ohms) and then electrically connected to pin 5 of U14. Pin 9 is connected in series with resistor R42 (47 ohms) and then electrically connected to pin 5 of U15. Pin 12 is electrically connected to pins 9 and 8 and grounded. Pins 13 and 14 are not connected. Pin 4 is connected to the 5V signal output from U16 and connected in series with capacitor C26 (100nF) and then grounded. Pin 2 is connected to J3. Pin 3 is electrically connected to pin 2 of J3, pin 6 is electrically connected to pin 1 of J3, pin 5 is electrically connected to pin 4 of J3, pin 10 is electrically connected to pin 3 of J4, pin 11 is electrically connected to pin 2 of J4, pins 13 and 14 are not connected, pin 16 is connected to the 24V input power supply 2 and connected in series with the 100nF capacitor C28 and then grounded, the positive terminal of the 10uF capacitor E3 is electrically connected to pin 16 of U13, and the negative terminal is electrically connected to the 100nF capacitor C28 and grounded.

[0052] Pin 3 of J2 is connected to the negative terminal of diode D15 of model SPTS340U, the positive terminal of D15 is connected to the 5V electrical signal +5VISO2 output by U10, and pin 4 is grounded; pin 1 of J4 is connected to the positive terminal of diode D27 of model SPTS340U, the negative terminal of D27 is connected to the 24V input power supply 2, and pin 4 is grounded.

[0053] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. An incremental encoder level conversion module, characterized in that, The circuit includes an encoder (1), a 24V input power supply (2), a 5V differential to single-ended circuit module (3), a drive optocoupler circuit module (4), a single-ended to 24V differential signal circuit module (5), a first 24V to 5V circuit (6), and a second 24V to 5V circuit (7). The 5V differential signal output by the encoder (1) is connected to the 5V differential to single-ended circuit module (3) via an input connector. The 5V differential to single-ended circuit module (3) is connected to the drive optocoupler circuit module (4), and the drive optocoupler circuit module (4) is connected to the single-ended to 24V differential signal circuit module (7). The 4V differential signal circuit module (5) outputs a 24V differential signal through an output connector. The 24V input power supply (2) is connected to the single-ended to 24V differential signal circuit module (5). The 24V input power supply (2) is connected to the drive optocoupler circuit module (4) through the first 24V to 5V circuit (6). The 24V input power supply (2) is connected to the encoder (1), the 5V differential to single-ended circuit module (3), and the drive optocoupler circuit module (4) through the second 24V to 5V circuit (7).

2. The incremental encoder level conversion module according to claim 1, characterized in that, The 5V differential to single-ended circuit module (3) uses a differential signal processing chip of model AM26LS32.

3. The incremental encoder level conversion module according to claim 1, characterized in that, The driving optocoupler circuit module (4) uses an isolation optocoupler and a Schmitt positive logic chip with model number SN74AHC1G04.

4. The incremental encoder level conversion module according to claim 1, characterized in that, The single-ended to 24V differential signal circuit module (5) uses a driver of model OL7272.

5. The incremental encoder level conversion module according to claim 1, characterized in that, The first 24V to 5V circuit (6) uses a power module of model K7805.

6. The incremental encoder level conversion module according to claim 1, characterized in that, The second 24V to 5V circuit (7) uses a power module with model number WRB2405ZP-3WR2.

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