A frequency converter arrangement

Abstract

The application relates to the technical field of frequency converters, and provides a frequency converter device, which comprises a power supply module, an auxiliary power supply module, an external power supply module, a frequency converter control module and a voltage processing module; a first voltage output end and a second voltage output end of the power supply module are connected with a first voltage input end of the voltage processing module and a voltage input end of the auxiliary power supply module respectively; a voltage output end of the auxiliary power supply module is connected with a voltage input end of the external power supply module and a voltage input end of the frequency converter control module; a voltage output end of the external power supply module is connected with a second voltage input end of the voltage processing module; and a voltage output end of the voltage processing module is connected with a voltage input end of a motor. The application can improve the reliability of the frequency converter.

Description

Technical Field

[0001] This application relates to the field of frequency converter technology, and in particular to a frequency converter device. Background Technology

[0002] Inverters play a crucial role in industrial production and public utilities, ensuring efficient energy utilization, precise motor control, and stable equipment operation. They can precisely adjust motor speeds according to actual needs, allowing motors to operate at appropriate speeds under different conditions. For example, in industrial production, the speed of conveyor belt motors and fan motors can be adjusted according to the production process, achieving refined production control. In thermal power plants, coal feeders are important auxiliary equipment, and most currently operate using variable frequency speed control. However, inverters will lock out their output during periods of low grid voltage (which is usually instantaneous or short-lived), triggering the furnace fire suppression system. In recent years, shutdowns caused by inverter low-voltage lockout have occurred frequently in thermal power plants across the country. Similarly, incidents of airport flight delays and shopping mall escalator shutdowns due to inverter lockout caused by grid voltage fluctuations are also constantly occurring. Therefore, improving the stability of inverters during grid fluctuations is essential.

[0003] Inverters are crucial for energy efficiency, precise motor control, and stable equipment operation in industrial production and public utilities. However, they face multiple technical challenges in complex application scenarios: grid harmonics can cause inverter input current distortion, increased losses, and protection malfunctions; existing passive filtering methods are insufficient for suppressing dynamic harmonics. Incorrect power / motor wiring connections can easily lead to overvoltage and overcurrent damage to components; traditional inverters lack intelligent detection and automatic correction mechanisms, relying on manual troubleshooting, which increases debugging risks. When the motor decelerates or brakes, regenerated energy is fed back to the DC bus; improper energy processing device configuration can easily cause overvoltage faults, while existing fixed-energy-consumption braking schemes have low recovery efficiency and are not coordinated with energy storage systems. Therefore, current inverters suffer from low reliability. Utility Model Content

[0004] This application provides a frequency converter device that can solve the problem of low reliability of frequency converters.

[0005] This application provides a frequency converter device, which includes: a power supply module, an auxiliary power supply module, an external power supply module, a frequency converter control module, and a voltage processing module; The voltage input terminal of the power supply module is connected to the mains power. The first voltage output terminal of the power supply module is connected to the first voltage input terminal of the voltage processing module. The second voltage output terminal of the power supply module is connected to the voltage input terminal of the auxiliary power supply module. The voltage output terminal of the auxiliary power supply module is connected to the voltage input terminal of the external power supply module and the voltage input terminal of the frequency converter control module. The voltage output terminal of the external power supply module is connected to the second voltage input terminal of the voltage processing module. The voltage output terminal of the voltage processing module is connected to the voltage input terminal of the motor. The control signal output terminal of the frequency converter control module is connected to the control signal input terminal of the voltage processing module.

[0006] Optionally, the power supply module includes a wiring verification and correction unit, an AC input unit, and a harmonic mitigation unit connected in sequence. The voltage input terminal of the wiring verification correction unit is the voltage input terminal of the power supply module, the voltage output terminal of the harmonic control unit is the first voltage output terminal of the power supply module, and the first voltage output terminal of the AC input unit is the second voltage output terminal of the power supply module.

[0007] Optionally, the voltage processing module includes a rectifier unit, an inverter unit, and a buck-boost unit; The voltage input terminal of the rectifier unit is the first voltage input terminal of the voltage processing module, the first voltage input terminal of the buck-boost unit is the second voltage input terminal of the voltage processing module, the voltage output terminal of the inverter unit is the voltage output terminal of the voltage processing module, and the control signal input terminals of the buck-boost unit and the inverter unit are both control signal input terminals of the voltage processing module. The voltage output terminal of the rectifier unit is connected to the second voltage input terminal of the buck-boost unit and the voltage input terminal of the inverter unit, respectively. The voltage output terminal of the buck-boost unit is connected to the voltage input terminal of the inverter unit.

[0008] Optionally, the external power supply module is an external capacitor; The first end of the external capacitor is the voltage input terminal of the external power supply module, and the second end of the external capacitor is the voltage output terminal of the external power supply module.

[0009] Optionally, the inverter control module is a control circuit; The voltage input terminal of the control circuit is the voltage input terminal of the inverter control module, and the control signal output terminal of the control circuit is the control signal output terminal of the inverter control module.

[0010] Optionally, the wiring verification and correction unit includes a sensor, a phase sequence detector, and a relay connected in series; The sensor's input terminal is the voltage input terminal of the wiring verification and correction unit, and the relay's output terminal is the voltage output terminal of the wiring verification and correction unit.

[0011] Optionally, the AC input unit includes power management circuitry; The input terminal of the power management circuit is the voltage input terminal of the AC input unit, the first output terminal of the power management circuit is the first voltage output terminal of the AC input unit, and the second output terminal of the power management circuit is the second power output terminal of the AC input unit.

[0012] Optionally, the harmonic mitigation unit includes a series LC filter and an active power filter; The input terminal of the LC filter is the input terminal of the harmonic mitigation unit, and the output terminal of the active power filter is the output terminal of the harmonic mitigation unit.

[0013] The above-mentioned solution in this application has the following beneficial effects: In the embodiments of this application, the frequency converter device includes a power supply module, an auxiliary power supply module, an external power supply module, a frequency converter control module, and a voltage processing module. The voltage input terminal of the power supply module is connected to the mains power. The first voltage output terminal of the power supply module is connected to the first voltage input terminal of the voltage processing module. The second voltage output terminal of the power supply module is connected to the voltage input terminal of the auxiliary power supply module. The voltage output terminal of the auxiliary power supply module is connected to the voltage input terminals of the external power supply module and the frequency converter control module, respectively. The voltage output terminal of the external power supply module is connected to the second voltage input terminal of the voltage processing module. The voltage output terminal of the voltage processing module is connected to the voltage input terminal of the motor. The control signal output terminal of the frequency converter control module is connected to the control signal input terminal of the voltage processing module. Using the external power supply module and the power supply module to power the voltage processing module effectively improves the frequency converter's adaptability to different voltage fluctuations, reduces the probability of lockout, protects the motor, and thus improves the reliability of the frequency converter.

[0014] Other beneficial effects of this application will be described in detail in the following detailed description section. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the inverter device provided in this application. Detailed Implementation

[0017] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0018] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0019] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0020] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0022] To address the current issue of low reliability in frequency converters, this application provides a frequency converter device. The device includes a power supply module, an auxiliary power supply module, an external power supply module, a frequency converter control module, and a voltage processing module. The voltage input terminal of the power supply module is connected to mains power. The first voltage output terminal of the power supply module is connected to the first voltage input terminal of the voltage processing module. The second voltage output terminal of the power supply module is connected to the voltage input terminal of the auxiliary power supply module. The voltage output terminal of the auxiliary power supply module is connected to the voltage input terminals of both the external power supply module and the frequency converter control module. The voltage output terminal of the external power supply module is connected to the second voltage input terminal of the voltage processing module. The voltage output terminal of the voltage processing module is connected to the voltage input terminal of the motor. The control signal output terminal of the frequency converter control module is connected to the control signal input terminal of the voltage processing module. By using the external power supply module and the power supply module to power the voltage processing module, the adaptability of the frequency converter to different voltage fluctuations is effectively improved, the probability of lockout is reduced, motor protection is achieved, and thus the reliability of the frequency converter is improved.

[0023] The frequency converter device provided in this application will be illustrated below with specific examples.

[0024] like Figure 1 As shown, the frequency converter device includes: a power supply module, an auxiliary power supply module, an external power supply module, a frequency converter control module, and a voltage processing module.

[0025] The voltage input terminal of the power supply module is connected to the mains power. The first voltage output terminal of the power supply module is connected to the first voltage input terminal of the voltage processing module. The second voltage output terminal of the power supply module is connected to the voltage input terminal of the auxiliary power supply module. The voltage output terminal of the auxiliary power supply module is connected to the voltage input terminal of the external power supply module and the voltage input terminal of the frequency converter control module. The voltage output terminal of the external power supply module is connected to the second voltage input terminal of the voltage processing module. The voltage output terminal of the voltage processing module is connected to the voltage input terminal of the motor. The control signal output terminal of the frequency converter control module is connected to the control signal input terminal of the voltage processing module.

[0026] It should be noted that the power supply module is used to correct the mains power and then supply power to the voltage processing module and the auxiliary power supply module. The external power supply module is used to supply power to the voltage processing module when the voltage at the first voltage output terminal of the power supply module is abnormal (such as the voltage being between 0-10% and greater than 150% of the rated voltage). The auxiliary power supply module is used to supply power to the external power supply module and the inverter control module, and also to charge the external power supply module. The auxiliary power supply module is charged through the power supply module. The inverter control module is used to control the voltage processing module. The voltage processing module is used to perform frequency conversion processing such as step-up / step-down, rectification, and inversion on the input voltage, and outputs the frequency-converted voltage to the motor to power the motor. By introducing the external power supply module, the situation of the inverter device being locked when the mains power is abnormal is reduced, the adaptability of the inverter device to voltage fluctuations is improved, and thus the reliability of the inverter device is improved.

[0027] The power supply module includes a wiring verification and correction unit, an AC input unit, and a harmonic mitigation unit connected in sequence. The voltage input terminal of the wiring verification and correction unit is the voltage input terminal of the power supply module, the voltage output terminal of the harmonic mitigation unit is the first voltage output terminal of the power supply module, and the first voltage output terminal of the AC input unit is the second voltage output terminal of the power supply module.

[0028] The aforementioned wiring verification and correction unit includes a sensor, a phase sequence detector, and a relay connected in series. The sensor's input terminal is the voltage input terminal of the wiring verification and correction unit, and the relay's output terminal is the voltage output terminal. The sensor detects the phase sequence of the input voltage. The phase sequence detector has a reference phase sequence. When the phase sequence of the input voltage matches the reference phase sequence, it outputs a low level; otherwise, it outputs a high level. When the relay receives a low-level signal from the phase sequence detector, it directly transmits the input voltage to the AC input unit. When it receives a high-level signal, the relay switches the phase sequence of the input voltage to a preset phase sequence before transmitting it to the AC input unit. This effectively avoids device burnout or malfunction caused by wiring errors, improving the safety and convenience of equipment installation and maintenance.

[0029] The aforementioned AC input unit includes a power management circuit. The input terminal of the power management circuit is the voltage input terminal of the AC input unit. The first output terminal of the power management circuit is the first voltage output terminal of the AC input unit. The second output terminal of the power management circuit is the second voltage output terminal of the AC input unit. The second output terminal of the power management circuit is connected to the voltage input terminal of the harmonic mitigation unit and is used to provide AC power to the harmonic mitigation unit and the auxiliary power supply module.

[0030] The aforementioned harmonic mitigation unit consists of a series LC filter and an active power filter. The input terminal of the LC filter is the input terminal of the harmonic mitigation unit, and the output terminal of the active power filter is the output terminal of the harmonic mitigation unit. It is used to filter the voltage input from the AC input unit and output it to the voltage processing module, suppressing high-frequency harmonics and dynamically compensating for reverse-phase current, reducing the total harmonic distortion rate of the input current. This effectively reduces heat generation and losses in the inverter's internal components. Combined with the inverter control module, it optimizes protection thresholds, preventing overcurrent / overvoltage malfunctions caused by harmonics, and enhancing operational stability and equipment lifespan in complex power grid environments.

[0031] The voltage processing module includes a rectifier unit, an inverter unit, and a buck-boost unit. The voltage input terminal of the rectifier unit is the first voltage input terminal of the voltage processing module, the first voltage input terminal of the buck-boost unit is the second voltage input terminal of the voltage processing module, the voltage output terminal of the inverter unit is the voltage output terminal of the voltage processing module, and the control signal input terminals of the buck-boost unit and the inverter unit are both control signal input terminals of the voltage processing module. The voltage output terminal of the rectifier unit is connected to the second voltage input terminal of the buck-boost unit and the voltage input terminal of the inverter unit, respectively, and the voltage output terminal of the buck-boost unit is connected to the voltage input terminal of the inverter unit.

[0032] It should be noted that the frequency converter also includes a regenerative brake; the motor's output terminal is connected to the voltage input terminal of the regenerative brake, and the regenerative brake's voltage output terminal is connected to the third voltage input terminal of the voltage processing module. The second voltage input terminal of the buck-boost unit is the third voltage input terminal of the voltage processing module. The regenerative brake detects the motor's rotor speed; when the motor is braking, the speed decreases, and the kinetic energy is converted into electrical energy through the regenerative brake.

[0033] The voltage processing module can be used for traditional frequency converters.

[0034] The aforementioned rectifier unit is a rectifier used to convert the input alternating current (AC) into direct current (DC).

[0035] The aforementioned inverter unit is an inverter used to convert the input DC power into AC power.

[0036] The aforementioned step-up and step-down unit consists of a step-up converter and a step-down converter connected in parallel, used to step up and down the input voltage. It also includes a step-up and step-down switch for controlling the on / off state of the step-up and step-down converters, a control switch for controlling the voltage input, and a voltage sensor. The input terminal of the voltage sensor is the voltage input terminal of the step-up and step-down unit, and the output terminal of the voltage sensor is connected to the control terminal of the step-up and step-down switch and the control switch. The output terminals of the step-up and step-down converters are the voltage output terminals of the step-up and step-down unit. The control switch is connected in series with the step-up and step-down switch. The first terminal of the step-up and step-down switch is connected to the input terminal of the step-up and step-down converters, and the second terminal of the control switch is connected to the output terminal of the voltage sensor.

[0037] The voltage sensor monitors the input voltage. When the input voltage from the rectifier unit is normal, it outputs a high-level signal to the control switch and the buck-boost switch. The control switch connects to the rectifier unit, and the buck-boost switch connects to the boost converter. The buck-boost unit boosts the voltage output from the rectifier unit and inputs it to the inverter unit and the external power supply module. When the input voltage from the rectifier unit is abnormal (e.g., the voltage is between 0-10% or greater than 150% of the rated voltage), it outputs a low-level signal to the control switch and the buck-boost switch. The control switch connects to the external power supply module, and the buck-boost switch connects to the buck converter. The buck-boost unit reduces the voltage output from the external power supply module and inputs it to the inverter unit. When the input voltage from the regenerative brake is detected, the control switch is disconnected and outputs a high-level signal to the buck-boost switch. The buck-boost switch connects to the boost converter, and the buck-boost unit boosts the voltage output from the regenerative brake and inputs it to the external power supply module to charge it.

[0038] The external power supply module is an external capacitor; the first terminal of the external capacitor is the voltage input terminal of the external power supply module, and the second terminal of the external capacitor is the voltage output terminal of the external power supply module. It is used to store the input voltage.

[0039] The auxiliary power supply module is an auxiliary power source. The input terminal of the auxiliary power source is the voltage input terminal of the auxiliary power supply module, and the output terminal of the auxiliary voltage is the voltage output terminal of the auxiliary power supply module.

[0040] For example, the external power supply module can also be an external power source, with the first terminal of the external power source being the voltage input terminal of the external power supply module, the second terminal of the external power source being the voltage output terminal of the external power supply module, and the control signal input terminal of the external power source being the control signal input terminal of the external power supply module.

[0041] The inverter control module is a control circuit; the voltage input terminal of the control circuit is the voltage input terminal of the inverter control module, and the control signal output terminal of the control circuit is the control signal output terminal of the inverter control module.

[0042] The control circuit includes a first switching transistor corresponding to the inverter unit and a second switching transistor corresponding to the buck-boost unit (the first and second switching transistors can be metal-oxide-semiconductor field-effect transistors (MOS), insulated-gate bipolar transistors (IGBT), etc.), used to control the on / off state of the inverter unit and the buck-boost unit. The sources of the first and second switching transistors are connected to the voltage output terminal of the auxiliary power supply module, the drain of the first switching transistor is connected to the control signal input terminal of the inverter unit, and the drain of the second switching transistor is connected to the control signal input terminal of the buck-boost unit. The gates of the first and second switching transistors are connected to an isolation chip (the input terminal of the isolation chip is connected to a driver chip). The driver chip outputs control signals to control the on / off state of the first and second switching transistors based on the voltage value of the first output terminal of the power supply module. The isolation chip electrically isolates the two control signals output by the driver chip and inputs them to the gates of the first and second switching transistors, respectively.

[0043] The aforementioned regenerative brake converts the mechanical motion during motor deceleration or braking into single-phase direct current. It is used to process the regenerative energy generated during motor deceleration / braking. At low capacity, the regenerative energy is stored in an external power supply module via a step-up / step-down unit, providing energy reserves for grid fluctuations. This achieves efficient recovery and utilization of regenerative energy, reducing overvoltage faults while improving system energy efficiency.

[0044] It should be noted that the inverter control module enables control of the inverter under different supply voltages. 1. When the voltage at the first voltage output terminal of the power supply module is at the rated voltage, the control signal of the first switching transistor output by the driver chip is high level, and the control signal of the second switching transistor is low level (if the control signal is high level, the switching transistor is connected; if it is low level, the switching transistor is disconnected). The voltage at the first voltage output terminal of the power supply module is processed by the rectifier unit and the inverter unit to supply power to the motor. In this case, the frequency converter control module outputs a control signal to control the buck-boost unit not to process the voltage at the first voltage output terminal of the power supply module, and to control the external power supply module not to supply power to the buck-boost module.

[0045] 2. When the voltage at the first voltage output terminal of the power supply module is 10%-90% or 120%-150% of the rated voltage, both control signals output by the drive chip are at a high level. The inverter control module outputs a control signal to control the step-up and step-down unit to participate in the voltage processing. This enables the step-up and step-down unit, rectifier unit, and inverter unit to process the voltage at the first voltage output terminal of the power supply module, thereby supplying power to the motor. At the same time, it controls the external power supply module not to supply power to the step-up and step-down module.

[0046] 3. When the voltage at the first voltage output terminal of the power supply module is between 0-10% and greater than 150% of the rated voltage, the power supply module stops supplying power and uses an external power supply module to supply power. Both control signals output by the driver chip are at a high level. The voltage at the voltage output terminal of the external power supply module is processed by the buck-boost unit, rectifier unit and inverter unit to supply power to the motor.

[0047] It is worth mentioning that using an external power supply module and a power supply module to power the voltage processing module effectively improves the inverter's adaptability to different voltage fluctuations, reduces the probability of lockout, and protects the motor. By recovering the regenerative electrical energy generated by the motor through the regenerative brake and voltage processing module, overvoltage faults and energy waste caused by direct recovery are effectively avoided, further improving the reliability of the inverter.

[0048] In addition, the frequency converter of this application has the following beneficial effects: 1. Improve operational stability: When power supply fluctuations occur, the system can use a dynamic voltage threshold adjustment algorithm to activate the step-up / step-down unit to stabilize the power supply quality to the motor. This design avoids the inverter shutdown caused by triggering lockout protection during low / high voltage (instantaneous or short-term) grid conditions. This is of great significance for special operating scenarios where shutdown is not possible, such as coal feeders in thermal power plants and conveyor belt systems in airports, effectively reducing the risk of major production accidents and ensuring the stable operation of equipment.

[0049] 2. Modular configuration option: For general scenarios, this inverter can handle most short-term / instantaneous voltage fluctuations. In some scenarios, if it is necessary to operate in extreme power supply environments such as extremely low voltage (0-10% of rated input voltage), a capacitor / battery module can be added. Different capacity capacitors / batteries can be customized for motors of different power to ensure that the motor can run continuously.

[0050] 3. Protect motor safety: If a traditional frequency converter suddenly loses power or experiences a lockout due to extremely low supply voltage, a sudden restart could damage the motor and cause a mechanical accident. This frequency converter, however, can dynamically adjust to abnormal power supply conditions, preventing sudden lockouts and restarts caused by power supply anomalies. This reduces the risk of motor damage at the source, extends the motor's lifespan, and ensures the safe and stable operation of the mechanical system.

[0051] 4. Extend the overall service life of the equipment: In complex power environments, the frequent locking and restarting of traditional frequency converters can subject motors and other related equipment to significant current surges and mechanical stress. The frequency converter device of this application, through its stable power supply design, avoids frequent motor starts and stops during voltage anomalies, reducing damage to the motor and other equipment caused by current surges and mechanical stress. An external battery / capacitor module provides stable power support to the device, reducing wear and tear on various components during operation and extending the overall lifespan of the entire equipment system, including the motor.

[0052] 5. Wiring safety protection and intelligent error correction: The wiring verification and correction unit identifies potential problems such as incorrect power line connections and incorrect motor phase sequence in real time. It supports automatic software correction of adjustable wiring issues (such as reversed phase sequence) and provides forced power-off protection for irreversible hardware errors. This function avoids risks such as overvoltage damage to inverter output terminals and component burnout caused by wiring errors, significantly reducing the cost and safety hazards of manual troubleshooting during equipment installation and commissioning, and improving the reliability of initial system connection.

[0053] 6. High-efficiency recovery of regenerative energy and overvoltage suppression: Regenerative brakes are designed for scenarios involving regenerative power generation during motor deceleration / braking. They convert and store regenerative electrical energy in real time to an external battery / capacitor module, effectively preventing DC bus overvoltage faults (such as frequent overvoltage issues during crane descent). Combined with existing energy storage systems, they enable the recycling of regenerative energy, improving system energy efficiency by 10%-15%, while reducing energy waste from traditional fixed-energy braking and lowering equipment operating costs.

[0054] 7. Harmonic pollution control and reliability improvement: The harmonic mitigation unit integrates passive filtering and active compensation technologies to dynamically suppress major harmonic components such as the 5th and 7th harmonics in the power grid, reducing the total harmonic distortion of the input current to below 5% and improving the power factor to above 0.95. This design reduces the losses and heat generation of internal components in the inverter caused by harmonics, extends the lifespan of core components such as insulated-gate bipolar transistors and capacitors by more than 20%, and, in conjunction with the control circuit module, optimizes protection thresholds to avoid overcurrent / overvoltage malfunctions caused by harmonic interference, significantly enhancing operational stability in complex power grid environments.

[0055] The above description is the preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principles described in this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A frequency converter device, characterized in that, include: Power supply module, auxiliary power supply module, external power supply module, frequency converter control module, voltage processing module; The voltage input terminal of the power supply module is connected to the mains power. The first voltage output terminal of the power supply module is connected to the first voltage input terminal of the voltage processing module. The second voltage output terminal of the power supply module is connected to the voltage input terminal of the auxiliary power supply module. The voltage output terminal of the auxiliary power supply module is connected to the voltage input terminal of the external power supply module and the voltage input terminal of the frequency converter control module. The voltage output terminal of the external power supply module is connected to the second voltage input terminal of the voltage processing module. The voltage output terminal of the voltage processing module is connected to the voltage input terminal of the motor. The control signal output terminal of the frequency converter control module is connected to the control signal input terminal of the voltage processing module.

2. The frequency converter device according to claim 1, characterized in that, The power supply module includes a wiring verification and correction unit, an AC input unit, and a harmonic mitigation unit connected in sequence. The voltage input terminal of the wiring verification and correction unit is the voltage input terminal of the power supply module, the voltage output terminal of the harmonic control unit is the first voltage output terminal of the power supply module, and the first voltage output terminal of the AC input unit is the second voltage output terminal of the power supply module.

3. The frequency converter device according to claim 1, characterized in that, The voltage processing module includes a rectifier unit, an inverter unit, and a buck-boost unit; The voltage input terminal of the rectifier unit is the first voltage input terminal of the voltage processing module, the first voltage input terminal of the buck-boost unit is the second voltage input terminal of the voltage processing module, the voltage output terminal of the inverter unit is the voltage output terminal of the voltage processing module, and the control signal input terminals of the buck-boost unit and the inverter unit are both control signal input terminals of the voltage processing module. The voltage output terminal of the rectifier unit is connected to the second voltage input terminal of the buck-boost unit and the voltage input terminal of the inverter unit, respectively, and the voltage output terminal of the buck-boost unit is connected to the voltage input terminal of the inverter unit.

4. The frequency converter device according to claim 1, characterized in that, The external power supply module is an external capacitor; The first end of the external capacitor is the voltage input terminal of the external power supply module, and the second end of the external capacitor is the voltage output terminal of the external power supply module.

5. The frequency converter device according to claim 1, characterized in that, The inverter control module is a control circuit; The voltage input terminal of the control circuit is the voltage input terminal of the inverter control module, and the control signal output terminal of the control circuit is the control signal output terminal of the inverter control module.

6. The frequency converter device according to claim 2, characterized in that, The wiring verification and correction unit includes a sensor, a phase sequence detector, and a relay connected in series; The input terminal of the sensor is the voltage input terminal of the wiring verification and correction unit, and the output terminal of the relay is the voltage output terminal of the wiring verification and correction unit.

7. The frequency converter device according to claim 2, characterized in that, The AC input unit includes a power management circuit; The input terminal of the power management circuit is the voltage input terminal of the AC input unit, the first output terminal of the power management circuit is the first voltage output terminal of the AC input unit, and the second output terminal of the power management circuit is the second power output terminal of the AC input unit.

8. The frequency converter device according to claim 2, characterized in that, The harmonic mitigation unit includes an LC filter and an active power filter connected in series. The input terminal of the LC filter is the input terminal of the harmonic mitigation unit, and the output terminal of the active power filter is the output terminal of the harmonic mitigation unit.

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