Motor system capable of realizing stable rotating speed

Abstract

The utility model relates to the technical field of industrial electrical automation, in particular to a motor system capable of realizing stable rotating speed, which comprises an on-site speed regulation control potentiometer, an isolator, a frequency converter and a motor, the isolator is provided with an independent power supply, and a slide rheostat is integrated in the on-site speed regulation control potentiometer; one fixed contact and one sliding contact of the slide rheostat are respectively connected to the input end of the isolator, the isolator is internally provided with a signal filtering module, an overvoltage protection circuit and an undervoltage protection circuit, the output end of the isolator is connected with the control end of the frequency converter, and the frequency converter is connected with the motor. The control end is used for controlling the rotating speed of the motor based on signals received by the control end. By adopting the motor system, the voltage used for final speed regulation is the output voltage of the isolator, the voltage is stable, and the interference of the field environment on the frequency converter and the speed regulation signal is avoided, so that the purpose of stably controlling the rotating speed of the motor can be achieved, and meanwhile, the power supply system of the frequency converter can be protected.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial electrical automation, in particular to a motor system capable of achieving stable rotational speed. Background Art

[0002] The statements in this section are merely intended to provide background information related to the technical solution of the present application to aid understanding, and they do not necessarily constitute prior art with respect to the technical solution of the present application.

[0003] In the field of industrial electrical automation control, precise control of motor speed is crucial for ensuring the stability and efficiency of production processes. Currently, variable frequency speed regulation (VVVSR) technology, as the mainstream method for motor speed control, has been widely used in various industrial automation systems. However, despite its many advantages, VVVSR technology often faces numerous challenges in practical applications, particularly in complex electromagnetic environments and over long transmission distances. The complexity of the surrounding electromagnetic environment is a major challenge. Industrial automation sites are often plagued by numerous electromagnetic radiation sources, such as high-voltage power supplies, high-frequency welding machines, and radio communication equipment. The electromagnetic fields generated by these devices during operation can strongly interfere with control circuits, causing inverter malfunctions or failures. For example, harmonic interference on the inverter input side can distort the power waveform and increase the harmonic content of the power grid, affecting the normal operation of other equipment and potentially damaging the inverter's internal electronic components. Furthermore, the impact of transmission distance cannot be ignored. As transmission distance increases, signal attenuation and noise interference become significant issues. During transmission, the control signals received by the inverter may be affected by cable resistance and inductance, as well as external electromagnetic radiation, resulting in signal degradation or even distortion. This signal attenuation and interference will directly affect the inverter's precise control of the motor speed, making it impossible for the motor to maintain a stable speed, thereby affecting the operating stability and product quality of the entire production line. Utility Model Content

[0004] In order to solve the above problems, the present application provides an electric motor system that can achieve stable speed, which includes: an on-site speed control potentiometer, an isolator, a frequency converter, and a motor, wherein the isolator has an independent power supply, and the on-site speed control potentiometer is integrated with a sliding rheostat, and a fixed contact and a sliding contact of the sliding rheostat are respectively connected to the input end of the isolator, and the isolator has a signal filtering module, an overvoltage protection circuit, and an undervoltage protection circuit. The output end of the isolator is connected to the control end of the frequency converter, and the frequency converter is connected to the motor for controlling the speed of the motor based on the signal received at the control end.

[0005] In one embodiment, the control terminal of the inverter is a 0-10V control terminal.

[0006] In one embodiment, the resistance variation range of the sliding rheostat integrated in the field speed control potentiometer is 0-10K ohms.

[0007] In one embodiment, the frequency converter has a display panel for displaying a control status.

[0008] In one embodiment, the isolator has a fault diagnosis and display unit.

[0009] In one embodiment, the fault diagnosis and display unit includes an LED indicator light or a liquid crystal display screen.

[0010] In one embodiment, the signal filtering module in the isolator is a low-pass filter.

[0011] By adopting the motor system of the present invention, the voltage used for the final speed regulation is the isolator output voltage, which is stable and avoids interference of the on-site environment on the frequency converter and the speed regulation signal, thereby achieving the purpose of stably controlling the motor speed and protecting the power supply system of the frequency converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The following further describes the embodiments of the present invention with reference to the accompanying drawings, wherein:

[0013] Figure 1 A schematic structural diagram of a motor system capable of achieving a stable speed according to an embodiment is shown. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0015] Figure 1A schematic diagram of a motor system capable of achieving stable speed according to one embodiment is shown. As shown, the motor system includes: a field speed control potentiometer 1, an isolator 2, a frequency converter 3, and a motor 4. Isolator 2 is an isolator with an independent power supply. Field speed control potentiometer 1 integrates a sliding rheostat, one fixed contact and one sliding contact of which are connected to the input of isolator 2. Potentiometer 1 and isolator 2 may be relatively far apart, and signal transmission between them can be subject to signal attenuation and noise interference, such as noise interference from high-voltage power supplies, high-frequency welding machines, and radio communication equipment in industrial sites. The output of isolator 2 is connected to the control terminal of frequency converter 3, which is connected to motor 4 to control the speed of motor 4 based on signals received from the control terminal. Isolator 2 provides signal isolation between field speed control potentiometer 1 and frequency converter 3 and uses changes in the output voltage of isolator 2 to control the motor speed control of the frequency converter, thereby achieving stable motor speed.

[0016] In one embodiment, the isolator 2 includes a signal filtering module, an overvoltage protection circuit, and an undervoltage protection circuit. The overvoltage protection circuit can be integrated within the isolator 2 to monitor the input voltage and automatically disconnect the circuit when the voltage exceeds a preset safety threshold, preventing device damage. The undervoltage protection circuit can also be integrated within the isolator 2 to trigger a protection mechanism when the input voltage falls below the normal operating range, ensuring stable device operation. The signal filtering module is used to filter out electromagnetic interference from the external environment and further improve the accuracy and stability of signal transmission.

[0017] In one embodiment, the control terminal of the frequency converter 3 is a 0-10V control terminal, and the final speed regulation uses a 0-10V voltage.

[0018] In one embodiment, the resistance variation range of the sliding rheostat integrated in the field speed control potentiometer 1 is 0-10K ohms.

[0019] In one embodiment, the frequency converter 3 has a display panel for displaying the control status, so that the operator can control the speed of the motor.

[0020] In one embodiment, the isolator 2 has a fault diagnosis and display unit, which can be, for example, an LED indicator light or a liquid crystal display screen to indicate whether the isolator 2 is working properly or what fault has occurred.

[0021] In one embodiment, the signal filtering module in the isolator 2 is a low-pass filter using a low-pass filter design to filter out high-frequency noise interference and ensure the stability of the transmission signal.

[0022] During use, the on-site speed control potentiometer 1 is connected to the input of the self-powered isolator 2, and then to the 0-10V control terminal of the frequency converter via the output of isolator 2. By adjusting the resistance of the sliding rheostat in the on-site speed control potentiometer 1, the output voltage of isolator 2 is synchronously changed according to the change in resistance value, thereby controlling the frequency converter 3 and ultimately the speed of the motor to meet the speed regulation requirements. Because the 0-10V voltage used for the final speed regulation is the isolator's output voltage, its voltage is stable, preventing interference from the on-site environment on the frequency converter and speed regulation signal, thereby achieving the goal of stable control of the motor speed and protecting the frequency converter's power supply system.

[0023] References herein to "various embodiments," "some embodiments," "one embodiment," or "an embodiment" refer to a particular feature, structure, or property described in connection with the embodiment being included in at least one embodiment. Thus, the appearances of the phrases "in various embodiments," "in some embodiments," "in one embodiment," or "in an embodiment" throughout this document do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or properties may be combined in any suitable manner in one or more embodiments. Thus, particular features, structures, or properties shown or described in connection with one embodiment may be combined, in whole or in part, with features, structures, or properties of one or more other embodiments without restriction, as long as the combination is not illogical or inoperable.

[0024] Having thus described several aspects of at least one embodiment of the present invention, it will be appreciated that various changes, modifications, and improvements will readily occur to those skilled in the art. Such changes, modifications, and improvements are intended to be within the spirit and scope of the present invention. While the present invention has been described with reference to certain embodiments, the present invention is not limited to the embodiments described herein and encompasses various changes and variations that may be made without departing from the scope of the present invention.

Claims

1. A motor system capable of achieving a stable rotational speed, characterized in that: include: An on-site speed control potentiometer (1), an isolator (2), a frequency converter (3), and a motor (4), wherein the isolator (2) has an independent power supply, a sliding rheostat is integrated inside the on-site speed control potentiometer (1), a fixed contact and a sliding contact of the sliding rheostat are respectively connected to the input end of the isolator (2), the isolator (2) has a signal filtering module, an overvoltage protection circuit, and an undervoltage protection circuit, the output end of the isolator (2) is connected to the control end of the frequency converter (3), and the frequency converter (3) is connected to the motor (4) for controlling the speed of the motor (4) based on a signal received by the control end.

2. The motor system capable of achieving stable speed according to claim 1, characterized in that: The control terminal of the frequency converter (3) is a 0-10V control terminal.

3. The motor system capable of achieving a stable rotational speed according to claim 1, wherein: The resistance variation range of the sliding rheostat integrated inside the on-site speed control potentiometer (1) is 0-10K ohms.

4. The motor system capable of achieving a stable rotational speed according to claim 1, wherein: The frequency converter (3) has a display panel for displaying a control state.

5. The motor system capable of achieving a stable rotational speed according to claim 1, wherein: The isolator (2) has a fault diagnosis and display unit.

6. The motor system capable of achieving a stable rotational speed according to claim 5, characterized in that: The fault diagnosis and display unit includes an LED indicator light or a liquid crystal display screen.

7. The motor system capable of achieving a stable rotational speed according to claim 1, characterized in that: The signal filtering module in the isolator (2) is a low-pass filter.

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