Detection device for frequency converter
By introducing a voltage comparator and an indicator device, the polarity of the inverter's DC output is automatically detected, solving the problems of time-consuming, labor-intensive, and error-prone manual inspection, and improving detection accuracy and equipment safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-07
- Publication Date
- 2026-04-03
AI Technical Summary
Existing frequency converters lack effective automatic polarity detection methods at the DC output end, making manual inspection time-consuming, labor-intensive, and prone to errors, which may lead to equipment damage.
By employing a voltage comparator, microcontroller, and indicator, the inverter's DC output polarity connection status can be automatically and in real time detected, and immediate feedback can be provided through the voltage comparator and indicator.
It reduces the frequency and error rate of manual inspections, improves production efficiency and quality, reduces maintenance and management costs, and ensures safe operation of equipment.
Smart Images
Figure CN224081792U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power electronic conversion equipment, specifically to a device for detecting the polarity of the DC output of a frequency converter. This device can automatically detect whether the positive and negative terminals of the DC output of the frequency converter are correctly wired, so as to ensure the safe operation of the equipment and avoid equipment damage caused by incorrect wiring. Background Technology
[0002] A frequency converter is a power electronic device widely used in industrial control, energy conversion, and motor drive fields. It primarily converts alternating current (AC) into AC with adjustable frequency and voltage, or converts it to direct current (DC) via an intermediate DC link for downstream equipment. Proper wiring is crucial for ensuring stable and safe operation of frequency converters. Especially for DC output frequency converters, accurate connection of the positive and negative terminals is essential for the normal operation of the load.
[0003] Currently, inverter equipment on the market typically lacks effective automated detection methods for DC output polarity. Users must manually check the wiring based on experience to ensure correct positive and negative connections. However, manual inspection is not only time-consuming and labor-intensive but also prone to errors due to operator negligence or lack of experience. Reversing the positive and negative terminals can damage the inverter module; for example, reversed DC output polarity can cause internal transistors to burn out. Utility Model Content
[0004] To address the aforementioned problems, this invention proposes a detection device for frequency converters, aiming to achieve automatic and real-time detection of the DC output polarity connection status of the frequency converter. This error detection and early warning mechanism not only significantly reduces the frequency and error rate of manual inspections but also effectively improves production efficiency and quality while reducing maintenance and management costs.
[0005] According to one aspect of the embodiments of this application, a detection device for a frequency converter is provided, comprising: a voltage comparator having a first input terminal, a second input terminal, and an output terminal, the first input terminal being connected to the DC output terminal of the frequency converter to receive the output voltage of the DC output terminal of the frequency converter, the second input terminal receiving a preset reference voltage, the voltage comparator comparing the output voltage with the preset reference voltage, and outputting a comparison result signal through the output terminal; a microcontroller having an input interface and an output interface, the input interface being connected to the output terminal of the voltage comparator to receive the comparison result signal of the voltage comparator, the microcontroller outputting a connection status indication signal through the output interface based on the comparison result signal, the connection status indication signal indicating whether the DC output positive and DC output negative terminals of the frequency converter are correctly or incorrectly connected; and an indication device connected to the output interface of the microcontroller to receive the connection status indication signal from the microcontroller and prompting the user whether the DC output positive and DC output negative terminals of the frequency converter are correctly or incorrectly connected.
[0006] In this way, by introducing a voltage comparator, a microcontroller, and an indicator, a DC output polarity detection function for a frequency converter is achieved, which features simple circuit logic and an intuitive detection method. When a wiring error occurs in the positive or negative terminal of the frequency converter's DC output, the voltage comparator can quickly identify it and generate a comparison result signal. After processing by the microcontroller, this signal can immediately issue visual or audible warnings to the user through the indicator, preventing equipment damage due to wiring errors.
[0007] In the embodiments of this application, the first input terminal of the voltage comparator is a non-inverting input terminal, and the second input terminal of the voltage comparator is an inverting input terminal. When the comparison result signal is a high-level signal, the connection status indication signal indicates that the DC output positive and DC output negative terminals of the frequency converter are correctly wired. When the comparison result signal is a low-level signal, the connection status indication signal indicates that the DC output positive and DC output negative terminals of the frequency converter are incorrectly wired.
[0008] In this way, the comparison result signal output by the voltage comparator can directly reflect whether the DC output positive and DC output negative terminals of the frequency converter are connected correctly or incorrectly. Thus, the microcontroller can read the output of the voltage comparator and determine whether the polarity of the DC output port is correct based on this output.
[0009] In the embodiments of this application, the microcontroller's input interface receives the comparison result signal from the output of the voltage comparator in the form of analog input. The microcontroller converts the comparison result signal into a digital value, compares the converted digital value with a preset value, and outputs a connection status indication signal indicating incorrect wiring through the output interface in response to the digital value being lower than the preset value. In response to the digital value being higher than the preset value, it outputs a connection status indication signal indicating correct wiring through the output interface.
[0010] In this way, continuously changing analog signals can be received and digitized, enabling the microcontroller to accurately determine the polarity connection status of the inverter's DC output, provide real-time feedback of correct or incorrect wiring signals, improve detection accuracy and response speed, and enhance system intelligence and reliability.
[0011] In the embodiments of this application, the indicating device is an LED indicator light, which is turned off based on a connection status indication signal indicating incorrect wiring and turned on based on a connection status indication signal indicating correct wiring.
[0012] This approach enables clear and immediate visual feedback, enhancing operational safety and equipment reliability.
[0013] In embodiments of this application, the indicating device is a buzzer, which emits sound based on a connection status indication signal indicating incorrect wiring and does not emit sound based on a connection status indication signal indicating correct wiring.
[0014] In this way, a buzzer provides auditory feedback, sounding an alarm when wiring is incorrect and remaining silent when wiring is correct, thus providing real-time audio prompts, enhancing operational alerts and system security.
[0015] In the embodiments of this application, the detection device further includes a timer, which counts for a predetermined time period each time the microcontroller outputs a connection status indication signal, and the microcontroller receives the comparison result signal of the voltage comparator from the voltage comparator after the predetermined time period has elapsed.
[0016] In this way, a predetermined time delay is made after each test before the next test is performed, in order to avoid unnecessary frequent testing and false alarms, and to improve testing efficiency and device stability.
[0017] In the embodiments of this application, the detection device and the frequency converter are integrated into one unit.
[0018] In this way, the positive and negative connection status of the DC output terminal can be automatically detected before the frequency converter starts, ensuring the safe operation of the equipment.
[0019] This application enables automatic, real-time detection of the DC output polarity connection status of a frequency converter. This polarity connection status detection mechanism not only significantly reduces the frequency and error rate of manual inspections but also effectively improves production efficiency and quality while reducing maintenance and management costs. Attached Figure Description
[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0021] Figure 1 A block diagram of a detection device for a frequency converter according to an embodiment of this application is shown.
[0022] Figure 2 A block diagram of a detection device for a frequency converter according to another embodiment of this application is shown.
[0023] Explanation of icon numbers:
[0024] 100,100' detection device;
[0025] 10. Voltage comparator;
[0026] 20 microcontrollers;
[0027] 30. Indicating device;
[0028] 40. Timer. Detailed Implementation
[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application.
[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such signals can be interchanged where appropriate so that the embodiments of this application 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 a non-exclusive inclusion; for example, including a series of steps or units or processes, methods, systems, products, or devices is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.
[0031] As discussed in the background section, users need to manually check the inverter's positive and negative terminals based on experience when wiring external loads to ensure correct connection. However, manual checking is not only time-consuming and labor-intensive, but also prone to errors due to operator negligence or lack of experience. Reversing the positive and negative terminals can damage the inverter module; for example, reversing the DC output terminals can cause internal transistors to burn out.
[0032] Therefore, the present invention is based on the introduction of a voltage comparator, a microcontroller, and an indicator device to realize a DC output polarity detection function for a frequency converter with simple circuit logic and intuitive detection method.
[0033] Figure 1 A block diagram of a detection device for a frequency converter according to an embodiment of this application is shown. Figure 1 As shown, the detection device 100 for the frequency converter may include: a voltage comparator 10, having a first input terminal, a second input terminal, and an output terminal. The first input terminal is connected to the DC output terminal of the frequency converter to receive the output voltage Vout of the DC output terminal of the frequency converter. The second input terminal receives a preset reference voltage Vref. The voltage comparator 10 compares the output voltage Vout with the preset reference voltage Vref and outputs a comparison result signal CMP through the output terminal; a microcontroller 20, having an input interface and an output interface. The input interface is connected to the output terminal of the voltage comparator 10 to receive the comparison result signal CMP from the voltage comparator 10. Based on the comparison result signal CMP, the microcontroller 20 outputs a connection status indication signal STS through the output interface. The connection status indication signal STS indicates whether the DC output positive and DC output negative terminals of the frequency converter are correctly or incorrectly connected; and an indication device 30, connected to the output interface of the microcontroller 20, for receiving the connection status indication signal STS from the microcontroller 20 and prompting the user whether the DC output positive and DC output negative terminals of the frequency converter are correctly or incorrectly connected.
[0034] like Figure 1 As shown, as an example, the first input terminal of voltage comparator 10 can be a non-inverting input terminal (+), and the second input terminal of voltage comparator 10 can be an inverting input terminal (-). When the comparison result signal CMP is a high-level signal, the connection status indication signal STS indicates that the DC output positive and DC output negative terminals of the frequency converter are correctly connected. When the comparison result signal CMP is a low-level signal, the connection status indication signal STS indicates that the DC output positive and DC output negative terminals of the frequency converter are incorrectly connected.
[0035] Specifically, the non-inverting input (+) of voltage comparator 10 receives the voltage to be measured output from the frequency converter, and the inverting input (-) of voltage comparator 10 receives a known reference voltage, which can be determined based on the magnitude of the voltage to be measured. If the comparison result signal output by voltage comparator 10 is high, then the voltage to be measured is determined to be higher than the reference voltage; if the comparison result signal output by voltage comparator 10 is low, then the voltage to be measured is determined to be lower than the reference voltage.
[0036] In addition, voltage comparator 10 has two power supply input terminals, VCC and VEE, to be connected to an external power supply. The external power supply supplies power to voltage comparator 10 so that voltage comparator 10 can work normally.
[0037] The input interface of the microcontroller 20 can receive the comparison result signal CMP from the output of the voltage comparator 10 in the form of analog input. The microcontroller 20 converts the comparison result signal CMP into a digital value, compares the converted digital value with a preset value, and outputs a connection status indication signal STS indicating incorrect wiring through the output interface in response to the digital value being lower than the preset value. In response to the digital value being higher than the preset value, it outputs a connection status indication signal STS indicating correct wiring through the output interface.
[0038] In this embodiment, the input interface of the microcontroller 20 can be the analog input pin of the microcontroller 20, that is, the analog input pin of the microcontroller 20 can be connected to the output of the voltage comparator 10, and the microcontroller 20 can include an analog-to-digital converter (not shown) to convert the comparison result signal CMP into a digital value.
[0039] As an example, the indicator device 30 may include an LED indicator, a buzzer, etc. The LED indicator may be turned off based on a connection status indication signal STS indicating incorrect wiring and turned on based on a connection status indication signal STS indicating correct wiring. The buzzer may sound based on a connection status indication signal STS indicating incorrect wiring and may not sound based on a connection status indication signal STS indicating correct wiring.
[0040] The indicating device of this application is not limited to the above example. Any indicating device that can prompt the user whether the DC output positive terminal and the DC output negative terminal of the frequency converter are correctly or incorrectly wired through visual, auditory, tactile or other means is within the scope of this application.
[0041] Already referenced Figure 1 This application describes a detection device for a frequency converter that can automatically and in real time detect the DC output polarity connection status of the frequency converter. This not only greatly reduces the frequency and error rate of manual inspection, but also effectively improves production efficiency and quality, and reduces maintenance and management costs.
[0042] The following is for reference Figure 2 This application describes a detection device for a frequency converter according to another embodiment. Figure 2 The detection device shown is Figure 1 The difference in the detection device shown is that, Figure 2 The detection device shown also includes a timer. The following will discuss... Figure 2 and Figure 1 The differences between the two will be described, but the components that are common to both will not be discussed further.
[0043] like Figure 2 As shown, the detection device 100' for a frequency converter according to another embodiment of this application further includes a timer 40. The timer 40 counts for a predetermined time period starting from each time the microcontroller 20 outputs a connection status indication signal STS. After the predetermined time period has elapsed, the microcontroller 20 receives a comparison result signal CMP from the voltage comparator 10. Therefore, by delaying the detection by a predetermined time period after each detection by the microcontroller 20 before performing the next detection, unnecessary frequent detection and false alarms can be avoided, improving detection efficiency and device stability.
[0044] As an example, timer 40 can be a separate component from microcontroller 20. This independent configuration allows the performance and accuracy of timer 40 to be unaffected by the operating state of microcontroller 20, providing a degree of redundancy and reliability for the detection mechanism.
[0045] Alternatively, timer 40 can be an internal timing clock of microcontroller 20. When timer 40 functions as an internal function of microcontroller 20, it can periodically trigger microcontroller 20 to execute a detection program according to a preset timing cycle, read the comparison result from the output of the voltage comparator, and obtain the latest polarity detection result. This integrated solution optimizes hardware resources and improves the overall efficiency and integration of the system while maintaining functional integrity.
[0046] In the embodiments of this application, the detection device 100 can be integrated with the frequency converter, automatically detecting the positive and negative connection status of the DC output terminal before the frequency converter starts, ensuring the safe operation of the equipment. Furthermore, the various components of the detection device 100—including the microcontroller 20, voltage comparator 30, and timer 40—are integrated inside the frequency converter, allowing it to be designed to form a unified structure with the frequency converter's main circuit board and control unit. This reduces external connections, lowers the risk of interference, and simplifies installation and maintenance procedures.
[0047] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0048] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interface; the indirect coupling or communication connection between units may be electrical or other forms.
[0049] The units described as separate components may or may not be physically separate. The units or components shown may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0050] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0051] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A detecting device for a frequency converter, characterized in that The application relates to a voltage comparator (10) having a first input end connected to a DC output end of a frequency converter to receive an output voltage of the DC output end of the frequency converter, a second input end receiving a preset reference voltage, and an output end outputting a comparison result signal of the output voltage and the preset reference voltage; a microcontroller (20) having an input interface connected to the output end of the voltage comparator (10) to receive the comparison result signal of the voltage comparator (10), and an output interface outputting a connection state indication signal based on the comparison result signal, the connection state indication signal indicating whether the DC output positive pole and the DC output negative pole of the frequency converter are correctly wired or incorrectly wired; and an indication device (30) connected to the output interface of the microcontroller (20) to receive the connection state indication signal from the microcontroller (20) and prompt a user whether the DC output positive pole and the DC output negative pole of the frequency converter are correctly wired or incorrectly wired. The first input end of the voltage comparator (10) is a non-inverted input end, the second input end of the voltage comparator (10) is an inverted input end, the connection state indication signal indicates that the DC output positive pole and the DC output negative pole of the frequency converter are correctly wired when the comparison result signal is a high-level signal, and the connection state indication signal indicates that the DC output positive pole and the DC output negative pole of the frequency converter are incorrectly wired when the comparison result signal is a low-level signal. The input interface of the microcontroller (20) receives the comparison result signal from the output end of the voltage comparator (10) in an analog input mode, the microcontroller (20) comprises an analog-to-digital converter converting the comparison result signal into a digital value, the microcontroller (20) compares the converted digital value with a preset value, and in response to the digital value being lower than the preset value, the microcontroller (20) outputs the connection state indication signal indicating incorrect wiring through the output interface, and in response to the digital value being higher than the preset value, the microcontroller (20) outputs the connection state indication signal indicating correct wiring through the output interface. The indication device (30) is an LED indicator, the LED indicator is turned off based on the connection state indication signal indicating incorrect wiring and is turned on based on the connection state indication signal indicating correct wiring. The indication device (30) is a buzzer, the buzzer emits a sound based on the connection state indication signal indicating incorrect wiring and does not emit a sound based on the connection state indication signal indicating correct wiring.
2. The detection device for a frequency converter according to claim 1, characterized in that, 3. The detection device for a frequency converter according to claim 2, characterized in that, 4. The detection device for a frequency converter according to claim 1, characterized in that, 5. The detection device for a frequency inverter according to claim 1, characterized by 6. The detection device for a frequency inverter according to claim 1, characterized by The detection device further comprises a timer (40) which starts timing a predetermined time period each time the connection state indication signal is output from the microcontroller (20), the microcontroller (20) receiving the comparison result signal of the voltage comparator (10) after the predetermined time period has elapsed.
7. The detection device for a frequency converter according to claim 1, characterized in that, The detection device is integrated with the frequency converter.