Signal enhancement device and motor speed measurement system

Abstract

The utility model discloses a signal enhancement device and a motor speed measurement system. The signal enhancement device is connected to the tachogenerator and comprises a first filtering module, the first end of the first filtering module is connected with a first signal input end, the second end of the first filtering module is connected with a second signal input end, and the second end of the first filtering module is further connected with a grounding end; the first filtering module is used for receiving an analog signal sent by the tachogenerator and filtering the analog signal; the control end of the signal conversion module is connected with the first end of the first filtering module, the first end is connected with the first signal output end, the second end is connected with the second signal output end, and the second end of the signal conversion module is further connected with the grounding end. The signal conversion module is used for outputting digital signals from the first end; and the voltage clamping module is connected between the control end and the second end of the signal conversion module and is used for limiting the voltage of the analog signal input into the control end of the signal conversion module. According to the utility model, the signal transmission effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of motor speed measurement technology, and in particular to a signal enhancement device and a motor speed measurement system. Background Technology

[0002] Motor speed adjustment relies on feedback from speed sensors. In large-scale applications, tachogenerators are commonly used for motor speed feedback. The tachogenerator outputs a speed signal based on the motor's rotational speed. When the motor speed is very low, the feedback speed signal has weak strength. In this case, if the signal receiving device is far from the motor, long cables can cause severe signal attenuation, or even the signal may be drowned out by interference noise. This can result in the signal receiving device failing to detect the speed signal at low speeds, leading to motor malfunction. Utility Model Content

[0003] This invention provides a signal enhancement device and a motor speed measurement system to improve signal transmission performance.

[0004] According to one aspect of the present invention, a signal enhancement device is provided, connected to a tachogenerator, the signal enhancement device comprising:

[0005] A first filtering module has a first end connected to a first signal input terminal, a second end connected to a second signal input terminal, and a second end also connected to a ground terminal; the first filtering module is used to receive and filter the analog signal emitted by the tachogenerator.

[0006] A signal conversion module is provided, wherein the control terminal of the signal conversion module is connected to the first terminal of the first filtering module, the first terminal of the signal conversion module is connected to the first signal output terminal, the second terminal of the signal conversion module is connected to the second signal output terminal, and the second terminal of the signal conversion module is also connected to the ground terminal; the signal conversion module is used to output a digital signal from the first terminal;

[0007] A voltage clamping module is connected between the control terminal and the second terminal of the signal conversion module, and is used to limit the voltage of the analog signal input to the control terminal of the signal conversion module.

[0008] Optionally, the first filtering module includes: a first capacitor;

[0009] The signal conversion module includes: a transistor;

[0010] The voltage clamping module includes a diode.

[0011] Optionally, the signal enhancement device further includes:

[0012] An anti-interference module is connected between the control terminal and the second terminal of the signal conversion module, and is used to filter out interference signals input to the control terminal of the signal conversion module.

[0013] Optionally, the anti-interference module includes: a first resistor.

[0014] Optionally, the signal enhancement device further includes:

[0015] The second filtering module is connected between the control terminal and the second terminal of the signal conversion module, and is used to filter the analog signal input to the control terminal of the signal conversion module;

[0016] The third filtering module is connected between the first signal output terminal and the second signal output terminal, and is used to filter the digital signal.

[0017] Optionally, the second filtering module includes: a second capacitor;

[0018] The third filtering module includes a third capacitor.

[0019] Optionally, the signal enhancement device further includes:

[0020] The first current limiting module is connected between the first end of the first filtering module and the control end of the signal conversion module, and is used to limit the current of the analog signal;

[0021] The second current limiting module is connected between the first end of the signal conversion module and the first signal output end, and is used to limit the current of the digital signal.

[0022] Optionally, the first current limiting module includes: a second resistor;

[0023] The second current limiting module includes: a third resistor.

[0024] According to another aspect of the present invention, a motor speed measuring system is provided, comprising: a tachogenerator and a signal enhancement device as described in any embodiment of the present invention.

[0025] The technical solution provided by this embodiment of the invention, by directly connecting the signal enhancement device to the tachogenerator, allows the analog signal emitted by the tachogenerator to be converted into a digital signal for transmission. Digital signals have better anti-interference performance than analog signals, increasing the effective transmission distance. This invention does not require changes to the installation and wiring structure of the tachogenerator, nor does it require additional power to the signal enhancement device, resulting in lower cost and better signal transmission performance.

[0026] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of a signal enhancement device according to an embodiment of the present utility model;

[0029] Figure 2 This is a schematic diagram of another signal enhancement device provided according to an embodiment of the present utility model;

[0030] Figure 3 This is a schematic diagram of a motor speed measuring system provided according to an embodiment of the present utility model. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] This utility model embodiment provides a signal enhancement device connected to a tachogenerator. Figure 1 This is a schematic diagram of a signal enhancement device provided in an embodiment of the present invention. (Reference) Figure 1 The signal enhancement device includes: a first filtering module 1, a signal conversion module 2, and a voltage clamping module 3. The first terminal of the first filtering module 1 is connected to a first signal input terminal, and the second terminal of the first filtering module 1 is connected to a second signal input terminal and also to a ground terminal; the first filtering module 1 is used to receive and filter the analog signal emitted by the tachogenerator. The control terminal of the signal conversion module 2 is connected to the first terminal of the first filtering module 1, the first terminal of the signal conversion module 2 is connected to a first signal output terminal, the second terminal of the signal conversion module 2 is connected to a second signal output terminal, and also to a ground terminal; the signal conversion module 2 is used to output a digital signal from the first terminal. The voltage clamping module 3 is connected between the control terminal and the second terminal of the signal conversion module 2 and is used to limit the voltage of the analog signal input to the control terminal of the signal conversion module 2.

[0034] The tachogenerator can be used to detect the motor's rotational speed and transmit the detected speed signal to a signal receiving device for speed reading. For example, the signal receiving device can be a controller. If the motor's rotational speed is low, the speed signal will have a weaker signal strength.

[0035] Because the speed signal is an analog signal, it experiences significant signal attenuation during transmission and is easily interfered with by noise. Directly reading the speed from this signal may result in inaccurate speed values, potentially leading to motor malfunction. By connecting the signal tachogenerator to a signal amplification device, the device processes the speed signal and converts it into a digital signal before inputting it to the controller. Analog signals have strong anti-interference capabilities. This analog-to-digital conversion of the speed signal improves its anti-interference performance and increases the transmission distance.

[0036] Specifically, the analog signal emitted by the tachogenerator is filtered by the first filtering module 1 and then transmitted to the signal conversion module 2. Because the tachogenerator is directly connected to the signal enhancement device, to prevent damage to the signal conversion module 2 due to excessively high voltage, the voltage clamping module 3 limits the voltage value of the analog signal, ensuring the safe and stable operation of the signal conversion module 2. When the signal conversion module 2 receives the analog signal, it can amplify the signal and convert it into a digital signal for transmission. For example, the digital signal can be a digital pulse signal.

[0037] The technical solution provided by this embodiment of the invention, by directly connecting the signal enhancement device to the tachogenerator, allows the analog signal emitted by the tachogenerator to be converted into a digital signal for transmission. Digital signals have better anti-interference performance than analog signals, increasing the effective transmission distance. This invention does not require changes to the installation and wiring structure of the tachogenerator, nor does it require additional power to the signal enhancement device, resulting in lower cost and better signal transmission performance.

[0038] Figure 2 This is a schematic diagram of another signal enhancement device provided in an embodiment of the present invention. (Reference) Figure 2 Based on the above embodiments, optionally, the first filtering module 1 includes a first capacitor C1, the signal conversion module 2 includes a transistor Q1, and the voltage clamping module 3 includes a diode D1.

[0039] The analog signal emitted by the tachogenerator 10 can be filtered by the first capacitor C1 to make the voltage of the analog signal smoother and more stable. To prevent the analog signal input to the base of transistor Q1 from being damaged due to excessive voltage, a diode D1 is connected in parallel between the base and emitter of transistor Q1 to clamp the base voltage of transistor Q1.

[0040] Specifically, because diode D1 has unidirectional conductivity, when its anode is grounded, the potential at that anode remains unchanged and can be used as a reference potential. The cathode, however, is the clamped terminal, and its potential changes and needs to be limited. When the potential at the cathode of diode D1 is too high, the clamping action of diode D1 forces the clamped terminal's potential towards the reference terminal, thereby limiting the voltage at the base of the input transistor Q1. Therefore, diode D1 can clamp the voltage at the base of the input transistor Q1 to a predetermined level without causing any change in the analog signal during the clamping process.

[0041] When the voltage of the analog signal is low, transistor Q1 can still amplify the analog signal and convert it into a digital signal before outputting it through the collector.

[0042] Continue to refer to Figure 2 Based on the above embodiments, the signal enhancement device may optionally further include an anti-interference module 4, which is connected between the control terminal and the second terminal of the signal conversion module 2, and is used to filter out interference signals from the control terminal of the input signal conversion module 2.

[0043] The signal enhancement device may contain interference signals, which could cause the signal conversion module 2 to turn on erroneously. The anti-interference module 4 filters out these interference signals, preventing them from being input to the control terminal of the signal conversion module 2, thus increasing the reliability of the signal enhancement device.

[0044] Based on the above embodiments, optionally, the anti-interference module 4 includes: a first resistor R1.

[0045] The first resistor R1 is connected between the base of transistor Q1 and the ground terminal, and can absorb interference signals input to the base of transistor Q1. For example, the interference signal can be leakage current, static electricity, etc.

[0046] Continue to refer to Figure 2 Based on the above embodiments, the signal enhancement device may optionally further include a second filtering module 5 and a third filtering module 6. The second filtering module 5 is connected between the control terminal and the second terminal of the signal conversion module 2, and is used to filter the analog signal from the control terminal of the input signal conversion module 2. The third filtering module 6 is connected between the first signal output terminal and the second signal output terminal, and is used to filter the digital signal.

[0047] The second filtering module 5 can filter the analog signal from the control terminal of the input signal conversion module 2 again. Compared with the setting method of only setting the first filtering module 1, setting the first filtering module 1 and the second filtering module 5 has a better filtering effect.

[0048] After the signal conversion module 2 converts the analog signal into a digital signal, the third filtering module 6 can filter the digital signal output by the signal conversion module 2, so that the digital signal output by the signal enhancement device has higher stability and better signal quality.

[0049] Based on the above embodiments, optionally, the second filtering module 5 includes a second capacitor C2, and the third filtering module 6 includes a third capacitor C3.

[0050] For example, the second capacitor C2 and the first capacitor C1 can have different capacitance values. Compared to a single capacitor configuration, both the second capacitor C2 and the first capacitor C1 can filter the analog signal. Furthermore, because the capacitance values ​​of the second capacitor C2 and the first capacitor C1 are different, their filtering frequency bands will also be different. Therefore, this configuration achieves a wider frequency filtering effect, resulting in higher stability of the analog signal input to the base of transistor Q1.

[0051] Continue to refer to Figure 2Based on the above embodiments, the signal enhancement device may optionally further include: a first current limiting module 7 and a second current limiting module 8. The first current limiting module 7 is connected between the first terminal of the first filtering module 1 and the control terminal of the signal conversion module 2, and is used to limit the current of the analog signal. The second current limiting module 8 is connected between the first terminal of the signal conversion module 2 and the first signal output terminal, and is used to limit the current of the digital signal.

[0052] The first current-limiting module 7 limits the current of the analog signal at the control terminal of the input signal conversion module 2, thereby protecting the stable operation of the signal conversion module 2. The second current-limiting module 8 limits the current of the digital signal output by the signal conversion module 2 to prevent excessive current from the signal enhancement device. Simultaneously, to prevent reverse current from flowing into the signal conversion module 2 due to high voltage from the signal receiving device connected to the signal enhancement device, the second current-limiting module 8 also limits the reverse current, preventing damage to the signal conversion module 2 caused by excessive voltage from the signal receiving device.

[0053] Based on the above embodiments, optionally, the first current limiting module 7 includes a second resistor R2; the second current limiting module 8 includes a third resistor R3.

[0054] This utility model embodiment provides a motor speed measurement system. Figure 3 This is a schematic diagram of a motor speed measuring system provided in an embodiment of the present invention. (Reference) Figure 3 The motor speed measurement system includes: a tachogenerator 10 and a signal enhancement device 20 as provided in any embodiment of the present invention.

[0055] The signal enhancement device 20 can be directly connected to the signal output line of the tachogenerator 10. The signal enhancement device 20 requires no additional power supply and can operate using only the weak signal from the speed measurement signal. Therefore, the signal enhancement device 20 will operate whenever the motor rotates and the tachogenerator 10 outputs a signal. The signal enhancement device 20 can convert analog signals into digital signals, which can be directly used by various digital circuits. This eliminates the need for analog-to-digital conversion circuits in the signal receiving equipment, simplifying its circuit structure.

[0056] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0057] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A signal enhancement device, characterized in that, Connected to the tachometer generator, the signal enhancement device includes: A first filtering module has a first end connected to a first signal input terminal, a second end connected to a second signal input terminal, and a second end also connected to a ground terminal; the first filtering module is used to receive and filter the analog signal emitted by the tachogenerator. A signal conversion module is provided, wherein the control terminal of the signal conversion module is connected to the first terminal of the first filtering module, the first terminal of the signal conversion module is connected to the first signal output terminal, the second terminal of the signal conversion module is connected to the second signal output terminal, and the second terminal of the signal conversion module is also connected to the ground terminal; the signal conversion module is used to output a digital signal from the first terminal; A voltage clamping module is connected between the control terminal and the second terminal of the signal conversion module, and is used to limit the voltage of the analog signal input to the control terminal of the signal conversion module.

2. The signal enhancement device according to claim 1, characterized in that, The first filtering module includes: a first capacitor; The signal conversion module includes: a transistor; The voltage clamping module includes a diode.

3. The signal enhancement device according to claim 1, characterized in that, The signal enhancement device further includes: An anti-interference module is connected between the control terminal and the second terminal of the signal conversion module, and is used to filter out interference signals input to the control terminal of the signal conversion module.

4. The signal enhancement device according to claim 3, characterized in that, The anti-interference module includes: a first resistor.

5. The signal enhancement device according to claim 1, characterized in that, The signal enhancement device further includes: The second filtering module is connected between the control terminal and the second terminal of the signal conversion module, and is used to filter the analog signal input to the control terminal of the signal conversion module; The third filtering module is connected between the first signal output terminal and the second signal output terminal, and is used to filter the digital signal.

6. The signal enhancement device according to claim 5, characterized in that, The second filtering module includes: a second capacitor; The third filtering module includes a third capacitor.

7. The signal enhancement device according to claim 1, characterized in that, The signal enhancement device further includes: The first current limiting module is connected between the first end of the first filtering module and the control end of the signal conversion module, and is used to limit the current of the analog signal; The second current limiting module is connected between the first end of the signal conversion module and the first signal output end, and is used to limit the current of the digital signal.

8. The signal enhancement device according to claim 7, characterized in that, The first current limiting module includes: a second resistor; The second current limiting module includes: a third resistor.

9. A motor speed measuring system, characterized in that, include: A tachogenerator and a signal enhancement device as described in any one of claims 1-8.

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