Feedback protection circuit of inverter

Abstract

The utility model provides a feedback protection circuit of an inverter. A DC boost driving module is connected with an inversion driving module through a DC boost bus; the inversion driving module is connected with the target AC bus, the inversion overvoltage and overcurrent sampling module is connected with the DC boost bus and the target AC bus, and the inversion overvoltage and overcurrent sampling module is connected with the light emitting end of the first optocoupler module. And the direct current boost driving module is connected with the light receiving end of the first optocoupler module so as to transmit the overvoltage and overcurrent signal to the direct current boost driving module. Overload states such as over-voltage and over-current can be quickly fed back to the direct-current boost driving end through the first optocoupler module for working state adjustment, the safety of the inverter and upstream and downstream electrical equipment is effectively guaranteed, and the user experience is improved.

Description

Technical Field

[0001] This application relates to the technical field of inverters, and particularly to a feedback protection circuit for an inverter. Background Art

[0002] An inverter is a converter that converts direct current electrical energy (such as batteries, accumulators, DC power stations, etc.) into fixed-frequency and fixed-voltage or frequency-modulated and voltage-regulated alternating current (such as 220V, 50Hz sine wave). A grid-tie inverter (GTI) is a special type of inverter. In addition to converting direct current into alternating current, the output alternating current can be synchronized with the frequency and phase of the mains power, so the output alternating current can be fed back to the mains power. Grid-tie inverters are commonly used in applications where a DC voltage source (such as a solar panel or a small wind turbine) is connected to the power grid.

[0003] During the research process of conceiving and forming this application, the applicant found at least the following problems. Grid-tie inverters often operate in outdoor environments and are subject to many interference factors. Inverters may experience overload situations such as overvoltage and overcurrent in complex working environments, which can cause great harm to the inverter and related upstream and downstream electrical equipment. Summary of the Utility Model

[0004] To alleviate the above problems, this application provides a feedback protection circuit for an inverter, including a DC boost drive module, a DC boost bus, an inverter drive module, a target AC bus, an inverter overvoltage and overcurrent sampling module, and a first optocoupler.

[0005] The DC boost drive module is connected to the inverter drive module through the DC boost bus. The DC boost drive module is used to boost a first DC voltage to a second DC voltage and output it to the DC boost bus.

[0006] The inverter drive module is connected to the target AC bus. The inverter drive module converts the second DC voltage into a target AC voltage and outputs it to the target AC bus.

[0007] The inverter overvoltage and overcurrent sampling module is respectively connected to the DC boost bus and the target AC bus, and is used to sample and monitor the overvoltage and overcurrent states on the DC boost bus and the target AC bus to generate overvoltage and overcurrent signals.

[0008] The inverter overvoltage and overcurrent sampling module is connected to the light-emitting end of the first optocoupler to output the overvoltage and overcurrent signals; the DC boost drive module is connected to the light-receiving end of the first optocoupler to transmit the overvoltage and overcurrent signals to the DC boost drive module.

[0009] Optionally, the first optocoupler module includes a first current-limiting resistor and a first optocoupler. The first current-limiting resistor is connected between the input end of the light-emitting end of the first optocoupler and the inverter overvoltage and overcurrent sampling module.

[0010] Optionally, the first optocoupler module further includes a second current-limiting resistor. The input end of the light-receiving end of the first optocoupler is connected to a preset voltage and the first end of the second current-limiting resistor. The second end of the second current-limiting resistor is connected to the DC boost driving module.

[0011] Optionally, the first optocoupler module further includes a first filter capacitor. The first filter capacitor is connected between the DC boost driving module and the ground.

[0012] Optionally, the feedback protection circuit of the inverter further includes a digital signal processing chip. The digital signal processing chip is respectively connected to the DC boost driving module, the inverter driving module, and the inverter overvoltage and overcurrent sampling module, and is configured to generate a first control signal and send it to the DC boost driving module, and generate a second control signal and send it to the inverter driving module according to the overvoltage and overcurrent signals of the inverter overvoltage and overcurrent sampling module.

[0013] Optionally, the feedback protection circuit of the inverter further includes a second optocoupler. The second optocoupler is connected between the digital signal processing chip and the inverter overvoltage and overcurrent sampling module, and is configured to transmit the overvoltage and overcurrent signals to the digital signal processing chip.

[0014] Optionally, the feedback protection circuit of the inverter further includes a third current-limiting resistor. The first end of the third current-limiting resistor is connected to the light-emitting end of the second optocoupler, and the second end of the third current-limiting resistor is connected to the inverter overvoltage and overcurrent sampling module to access the overvoltage and overcurrent signals.

[0015] Optionally, the feedback protection circuit of the inverter further includes an output overvoltage and overcurrent protection module. The output overvoltage and overcurrent protection module is connected between the digital signal processing chip and the second optocoupler, and is configured to perform input protection on the digital signal processing chip.

[0016] Optionally, the feedback protection circuit of the inverter further includes at least one boost circuit. The boost circuit is connected between the DC boost driving module and the DC boost bus, and is configured to boost the first DC voltage to the second DC voltage and output it to the DC boost bus under the drive of the DC boost driving module.

[0017] Optionally, the feedback protection circuit of the inverter further includes at least one inverter circuit, which is respectively connected to the DC boost bus, the inverter drive module, and the target AC bus, and is configured to invert the second DC voltage into the target AC voltage under the control of the inverter drive module and output it to the target AC bus.

[0018] The feedback protection circuit of the inverter provided by this application is based on the DC boost drive module connected to the inverter drive module through the DC boost bus; the inverter drive module is connected to the target AC bus, the inverter overvoltage and overcurrent sampling module is respectively connected to the DC boost bus and the target AC bus, the inverter overvoltage and overcurrent sampling module is connected to the light-emitting end of the first optocoupler, and the DC boost drive module is connected to the light-receiving end of the first optocoupler to transmit the overvoltage and overcurrent signals to the DC boost drive module; it can quickly feedback overload states such as overvoltage and overcurrent to the DC boost drive end through the first optocoupler for working state adjustment, effectively ensuring the safety of the inverter and upstream and downstream electrical equipment, and improving the user experience. Description of the Drawings

[0019] The drawings here are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application. To more clearly illustrate the technical solutions of the embodiments of this application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 It is the feedback protection circuit of the inverter according to an embodiment of this application.

[0021] Figure 2 It is a schematic diagram of the circuit connection of the inverter according to an embodiment of this application.

[0022] Figure 3 It is a schematic diagram of the circuit connection of the first optocoupler module according to an embodiment of this application.

[0023] Figure 4 It is a schematic diagram of the connection of the second optocoupler according to an embodiment of this application.

[0024] Figure 5 It is a schematic diagram of the circuit connection of the boost circuit according to an embodiment of this application.

[0025] Figure 6 It is a schematic diagram of the circuit connection of the boost circuit according to an embodiment of this application.

[0026] The realization, functional features, and advantages of the present application will be further described in conjunction with embodiments with reference to the accompanying drawings. Through the above-mentioned drawings, specific embodiments of the present application have been shown, and more detailed descriptions will be provided hereinafter. These drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed Embodiments

[0027] Here, the exemplary embodiments will be described in detail, and the examples are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0028] It should be noted that in this document, the term "including", "comprising", or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or device including a series of elements not only includes those elements but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article, or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article, or device including that element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined based on their explanations in the specific embodiments or further in combination with the context of the specific embodiments.

[0029] It should be understood that the specific embodiments described herein are merely used to explain the present application and are not used to limit the present application.

[0030] First Embodiment

[0031] The present application provides a feedback protection circuit for an inverter. Figure 1 It is a feedback protection circuit for an inverter according to an embodiment of the present application.

[0032] As Figure 1 shown, in one embodiment, the feedback protection circuit of the inverter includes a DC boost drive module 1, a DC boost bus 2, an inverter drive module 3, a target AC bus 4, an inverter overvoltage and overcurrent sampling module 5, and a first optocoupler module 6.

[0033] Please continue to refer to Figure 1, the DC boost drive module 1 is connected to the inverter drive module 3 through the DC boost bus 2, and the DC boost drive module 1 is used to boost a first DC voltage to a second DC voltage and output it to the DC boost bus 2.

[0034] Exemplarily, DC boost is to boost the relatively low DC voltage provided by the battery to the required voltage value. Its basic working process is that first, an electrical oscillation generates low-voltage pulses based on the first voltage. When the pulse transformer boosts to a predetermined voltage value, the pulse is rectified to obtain high-voltage direct current. Therefore, the DC boost circuit belongs to a type of DC / DC circuit. In this process, the DC circuit needs to be switched and driven at a specific frequency so as to generate an electrical oscillation with an appropriate frequency. The high-voltage DC voltage after DC boost, that is, the second voltage, is delivered to the DC boost bus.

[0035] Please continue to refer to Figure 1 , the inverter drive module 3 is connected to the target AC bus 4, and the inverter drive module 3 converts the second DC voltage into a target AC voltage and outputs it to the target AC bus 4.

[0036] Exemplarily, inverter drive mainly adjusts the waveform of the target AC voltage output by the inverter based on the second voltage by controlling the on and off of transistors. When the output voltage and current of the inverter are affected by the load, the driver will adjust the working state of the transistors to achieve a stable output from high-voltage DC to grid-connected AC voltage.

[0037] Please continue to refer to Figure 1 , the inverter overvoltage and overcurrent sampling module 5 is respectively connected to the DC boost bus 2 and the target AC bus 4, and is used to sample and monitor the overvoltage and overcurrent states on the DC boost bus 2 and the target AC bus 4 to generate overvoltage and overcurrent signals.

[0038] Exemplarily, during the process of converting from the first voltage to the target AC voltage, if overload situations such as overvoltage and overcurrent occur, they may be reflected on the DC boost bus or the target AC bus. Therefore, by sampling the DC boost bus and the target AC bus, the overvoltage and overcurrent situations of the DC boost bus and the target AC bus can be detected in a timely manner, so as to generate overvoltage and overcurrent signals and feedback them to the front-end working circuit.

[0039] Please continue to refer to Figure 1 , the inverter overvoltage and overcurrent sampling module 5 is connected to the light-emitting end of the first optocoupler module 6 to output the overvoltage and overcurrent signals. The DC boost drive module 1 is connected to the light-receiving end of the first optocoupler module to transmit the overvoltage and overcurrent signals to the DC boost drive module 1.

[0040] Exemplarily, an optocoupler, also known as an optical coupler or an opto-isolator, is an electro-optical-electrical conversion device that transmits electrical signals through light. It consists of at least a light source and a light receiver. The light source and the light receiver are assembled in the same sealed housing and isolated from each other by a transparent insulator. The pins of the light source are the input terminals, i.e., the light-emitting terminals, and the pins of the light receiver are the output terminals, i.e., the light-receiving terminals. Common light sources are light-emitting diodes, and light receivers are photosensitive diodes, photosensitive transistors, etc. The optocoupler can quickly transfer signals between two electrically isolated circuits, meeting the requirements of isolation, timeliness, and safety.

[0041] Exemplarily, when the inverter overvoltage and overcurrent sampling module outputs an overvoltage and overcurrent signal, through the connection of the first optocoupler module, the overvoltage and overcurrent signal is quickly transmitted to the DC boost drive module, enabling the DC boost drive module to timely adjust the drive control strategy or temporarily turn off the boost circuit, thereby avoiding the damage to the electrical circuit caused by the long-term persistence of overload states such as overvoltage and overcurrent.

[0042] In this embodiment, the DC boost drive module is connected to the inverter drive module through the DC boost bus; the inverter drive module is connected to the target AC bus, the inverter overvoltage and overcurrent sampling module is respectively connected to the DC boost bus and the target AC bus, the inverter overvoltage and overcurrent sampling module is connected to the light-emitting end of the first optocoupler module, and the DC boost drive module is connected to the light-receiving end of the first optocoupler module to transmit the overvoltage and overcurrent signal to the DC boost drive module; it can quickly feedback overload states such as overvoltage and overcurrent to the DC boost drive end through the first optocoupler module for working state adjustment, effectively ensuring the safety of the inverter and upstream and downstream electrical equipment and improving the user experience.

[0043] Second Embodiment

[0044] Figure 2 It is a schematic diagram of the circuit connection of the inverter according to an embodiment of the present application.

[0045] Figure 3 It is a schematic diagram of the circuit connection of the first optocoupler module according to an embodiment of the present application.

[0046] As Figure 2 and Figure 3 shown, optionally, on the basis of the first embodiment, the first optocoupler module 6 includes a first current-limiting resistor R337 and a first optocoupler G306B, and the first current-limiting resistor R337 is connected between the input terminal of the light-emitting end of the first optocoupler G306B and the inverter overvoltage and overcurrent sampling module 5.

[0047] Exemplarily, the first current-limiting resistor is a resistor connected in series in the circuit to limit the magnitude of the current in the branch where it is located, so as to prevent the current from being too large and burning out the first optocoupler connected in series. At the same time, the first current-limiting resistor can also play a voltage-dividing role to share the voltage with the first optocoupler in the case of high voltage.

[0048] Please continue to refer to Figure 2 and Figure 3 Optionally, the first optocoupler module 6 further includes a second current-limiting resistor R218. The input end of the light-receiving end of the first optocoupler G306B is connected to a preset voltage ENA and the first end of the second current-limiting resistor R218, and the second end of the second current-limiting resistor R218 is connected to the DC boost driving module 1.

[0049] Exemplarily, the second current-limiting resistor is a resistor connected in series in the circuit to limit the magnitude of the current in the branch where it is located, so as to prevent the current from being too large and burning out the DC boost driving module connected in series. At the same time, the second current-limiting resistor can also play a voltage-dividing role to divide the voltage with the DC boost driving module in the case of high voltage.

[0050] Please continue to refer to Figure 2 and Figure 3 Optionally, the first optocoupler module 6 further includes a first filter capacitor C218. The first filter capacitor C218 is connected between the DC boost driving module 1 and the ground.

[0051] Exemplarily, the first filter capacitor is connected in parallel to the light-receiving end of the first optocoupler and is an energy storage device used to reduce the AC pulsation ripple coefficient in the signal and smooth the DC signal output. In the electronic circuit for transmitting signals, the filter capacitor not only makes the DC output smooth and stable, reduces the influence of the alternating pulsating current on the electronic circuit, but also can absorb the current fluctuations generated during the operation of the electronic circuit and the interference introduced through the AC power supply, making the working performance of the electronic circuit more stable.

[0052] Please continue to refer to Figure 2 Optionally, the feedback protection circuit of the inverter further includes a digital signal processing chip 7. The digital signal processing chip 7 is respectively connected to the DC boost driving module 1, the inverter driving module 3, and the inverter overvoltage and overcurrent sampling module 5, and is used to generate a first control signal and send it to the DC boost driving module 1, and generate a second control signal and send it to the inverter driving module 3 according to the overvoltage and overcurrent signals of the inverter overvoltage and overcurrent sampling module 5.

[0053] A microprocessor for digital signal processing (digital signal processing chip, DSP) features the stability, repeatability, large-scale integration unique to digital devices, especially programmability and ease of implementing adaptive signal processing. It is used for high-speed digital signal processing, promoting its own application and development. Exemplarily, when the digital signal processing chip receives overvoltage and overcurrent signals, it notifies the DC boost drive module 1 and the inverter drive module 3 to adjust the drive strategy in a timely manner or temporarily turn off the drive circuit to ensure the safety of the inverter and upstream and downstream electrical equipment.

[0054] Figure 4 This is a schematic diagram of the connection of the second optocoupler in an embodiment of the present application.

[0055] Please continue to refer to Figure 2 and Figure 4 Optionally, the feedback protection circuit of the inverter further includes a second optocoupler G305. The second optocoupler G305 is connected between the digital signal processing chip 7 and the inverter overvoltage and overcurrent sampling module 5 for transmitting the overvoltage and overcurrent signals to the digital signal processing chip 7.

[0056] Exemplarily, when the inverter overvoltage and overcurrent sampling module outputs overvoltage and overcurrent signals, through the connection of the second optocoupler, the overvoltage and overcurrent signals are quickly transmitted to the digital signal processing chip, enabling the digital signal processing chip to timely control the DC boost drive module and the inverter drive module to adjust the drive control strategy or temporarily turn off the boost circuit, thereby avoiding damage to the electrical circuit caused by the long-term continuation of overload states such as overvoltage and overcurrent.

[0057] Please continue to refer to Figure 2 and Figure 4 Optionally, the feedback protection circuit of the inverter further includes a third current-limiting resistor R336. The first end of the third current-limiting resistor R336 is connected to the light-emitting end of the second optocoupler G305, and the second end of the third current-limiting resistor R336 is connected to the inverter overvoltage and overcurrent sampling module 5 to access the overvoltage and overcurrent signals.

[0058] Exemplarily, the third current-limiting resistor is composed of a resistor connected in series in the circuit to limit the magnitude of the current in the branch where it is located to prevent the inverter overvoltage and overcurrent sampling module connected in series from being burned out due to excessive current. At the same time, the third current-limiting resistor can also play a voltage-dividing role to divide the voltage with the second optocoupler in the case of high voltage.

[0059] Please continue to refer to Figure 2 and Figure 4 Optionally, the feedback protection circuit of the inverter further includes an output overvoltage and overcurrent protection module 8. The output overvoltage and overcurrent protection module 8 is connected between the digital signal processing chip 7 and the second optocoupler G305 for input protection of the digital signal processing chip 7.

[0060] Exemplarily, the output overvoltage and overcurrent protection is connected in series in the light-receiving end circuit of the second optocoupler to monitor the magnitudes of the current and voltage in the branch where it is located, so as to prevent the digital signal processing chip connected in series from being burned out due to excessive current or voltage.

[0061] Figure 5 Schematic diagram of the connection of the boost circuit according to an embodiment of the present application.

[0062] Please continue to refer to Figure 2 Figure 5 Optionally, the feedback protection circuit of the inverter further includes at least one boost circuit 9. The boost circuit 9 is connected between the DC boost driving module 1 and the DC boost bus 2, and is used to boost the first DC voltage to the second DC voltage under the drive of the DC boost driving module 1 and output it to the DC boost bus 2.

[0063] As Figure 5 shown, exemplarily, the boost circuit 9 includes a transformer T3, a diode D3, a second capacitor C209, a third capacitor C222, and a fourth capacitor C235. The primary winding of the transformer T2 is connected to the DC boost driving module 1 and is connected to a first voltage. Through the drive control of the quality boost driving module 1, a high-voltage pulse waveform is generated at the secondary end of the transformer T3. The positive end of the secondary end of the transformer T3 is connected to the first end of the diode D3, and the negative end of the secondary end of the transformer T3 is grounded. The secondary end of the transformer T3 is also connected in parallel with the second capacitor C209. The second end of the diode D3 is connected to the first ends of the third capacitor C22 and the fourth capacitor C235, and the second ends of the third capacitor C22 and the fourth capacitor C235 are grounded. Thus, the high-voltage pulse waveform generated at the secondary end of the transformer T3 is clipped by the diode D3 and then rectified by the third capacitor C22 and the fourth capacitor C235 into the second DC voltage, realizing the boost relative to the first DC voltage.

[0064] Figure 6 Schematic diagram of the connection of the boost circuit according to an embodiment of the present application.

[0065] Please continue to refer to Figure 2 and Figure 6 Optionally, the feedback protection circuit of the inverter further includes at least one inverter circuit 10 from DC to AC. The inverter circuit 10 is respectively connected to the DC boost bus 2, the inverter driving module 3, and the target AC bus 4, and is used to invert the second DC voltage into the target AC voltage under the control of the inverter driving module 3 and output it to the target AC bus 4.

[0066] As Figure 6As shown in the figure, the feedback protection circuit of the inverter includes two inverter circuits 10 to generate the AC voltages of the neutral line ACN and the live line ACL respectively. Taking one of them as an example, the inverter circuit 10 includes a fifth capacitor C803, a triode Q801, and the second end of the sixth capacitor C803 is connected to the control end of the triode Q801. The inverter drive module 3 receives the inverter control signal. The input end of the triode Q801 is connected to the DC boost bus 2 to access the second voltage, and the output end of the triode Q801 is connected to the neutral line CAN of the target AC bus 4 to generate the target AC voltage. A sixth capacitor C803 is also connected in parallel between the output end and the output end of the triode Q801 to filter the generated target AC voltage.

[0067] The feedback protection circuit of the inverter provided in this application is based on the DC boost drive module connected to the inverter drive module through the DC boost bus; the inverter drive module is connected to the target AC bus, the inverter overvoltage and overcurrent sampling module is respectively connected to the DC boost bus and the target AC bus, the inverter overvoltage and overcurrent sampling module is connected to the light-emitting end of the first optocoupler, and the DC boost drive module is connected to the light-receiving end of the first optocoupler to transmit the overvoltage and overcurrent signals to the DC boost drive module; it can quickly feedback overload states such as overvoltage and overcurrent to the DC boost drive end through the first optocoupler for working state adjustment, effectively ensuring the safety of the inverter and upstream and downstream electrical equipment, and improving the user experience.

[0068] It can be understood that the above scenarios are only examples and do not constitute a limitation on the application scenarios of the technical solutions provided in the embodiments of this application. The technical solutions of this application can also be applied to other scenarios. For example, as known to those of ordinary skill in the art, with the evolution of the system architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0069] The serial numbers of the embodiments of this application above are only for description and do not represent the advantages or disadvantages of the embodiments.

[0070] The steps in the method of the embodiments of this application can be adjusted, combined, and deleted according to actual needs.

[0071] The units in the devices of the embodiments of this application can be combined, divided, and deleted according to actual needs.

[0072] In this application, for the description of the same or similar term concepts, technical solutions, and / or application scenarios, generally only the first occurrence is described in detail. When it appears repeatedly later, for the sake of brevity, it is generally not described again. When understanding the technical solutions and other contents of this application, for the same or similar term concepts, technical solutions, and / or application scenario descriptions that are not described in detail later, reference can be made to the relevant detailed descriptions before them.

[0073] In this application, the descriptions of the various embodiments have their own focuses. For the parts not described or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0074] The technical features of the technical solutions of this application can be combined arbitrarily. For the sake of concise description, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope recorded in this application.

[0075] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of this application.

Claims

1. A feedback protection circuit for an inverter, characterized in that: It includes a DC boost drive module, a DC boost bus, an inverter drive module, a target AC bus, an inverter overvoltage and overcurrent sampling module and a first optical coupler module. The DC boost drive module is connected to the inverter drive module via the DC boost bus, and the DC boost drive module is used to boost the first DC voltage into a second DC voltage and output it to the DC boost bus; The inverter drive module is connected to the target AC bus, and the inverter drive module converts the second DC voltage into a target AC voltage and outputs the target AC voltage to the target AC bus; The inverter overvoltage and overcurrent sampling module is connected to the DC boost bus and the target AC bus, respectively, and is used to sample and monitor the overvoltage and overcurrent states on the DC boost bus and the target AC bus to generate an overvoltage and overcurrent signal; The inverter overvoltage and overcurrent sampling module is connected to the light-emitting end of the first optocoupler module to output the overvoltage and overcurrent signal; the DC boost driving module is connected to the light-receiving end of the first optocoupler module to transmit the overvoltage and overcurrent signal to the DC boost driving module.

2. The feedback protection circuit of an inverter according to claim 1, characterized in that: The first optocoupler module includes a first current limiting resistor and a first optocoupler, and the first current limiting resistor is connected between the input end of the first optocoupler light-emitting end and the inverter overvoltage and overcurrent sampling module.

3. The feedback protection circuit of an inverter according to claim 2, characterized in that: The first optocoupler module also includes a second current limiting resistor, the input end of the first optocoupler light receiving end is connected to a preset voltage and a first end of the second current limiting resistor, and the second end of the second current limiting resistor is connected to the DC boost driving module.

4. The feedback protection circuit of an inverter according to claim 3, characterized in that: The first optical coupling module further includes a first filter capacitor, and the first filter capacitor is connected between the DC boost driving module and the ground.

5. The feedback protection circuit of an inverter according to any one of claims 1 to 4, characterized in that: The feedback protection circuit of the inverter also includes a digital signal processing chip, which is respectively connected to the DC boost drive module, the inverter drive module and the inverter overvoltage and overcurrent sampling module, and is used to generate a first control signal and send it to the DC boost drive module according to the overvoltage and overcurrent signal of the inverter overvoltage and overcurrent sampling module, and generate a second control signal and send it to the inverter drive module.

6. The feedback protection circuit of an inverter according to claim 5, characterized in that: The feedback protection circuit of the inverter also includes a second optocoupler, which is connected between the digital signal processing chip and the inverter overvoltage and overcurrent sampling module, and is used to transmit the overvoltage and overcurrent signals to the digital signal processing chip.

7. The feedback protection circuit of an inverter according to claim 6, characterized in that: The feedback protection circuit of the inverter also includes a third current limiting resistor, a first end of the third current limiting resistor is connected to the second optocoupler light-emitting end, and a second end of the third current limiting resistor is connected to the inverter overvoltage and overcurrent sampling module to access the overvoltage and overcurrent signal.

8. The feedback protection circuit of an inverter according to claim 6, characterized in that: The feedback protection circuit of the inverter further includes an output overvoltage and overcurrent protection module, which is connected between the digital signal processing chip and the second optocoupler and is used for input protection of the digital signal processing chip.

9. The feedback protection circuit of an inverter according to claim 6, characterized in that: The feedback protection circuit of the inverter also includes at least one boost circuit, which is connected between the DC boost drive module and the DC boost bus, and is used to boost the first DC voltage to the second DC voltage and output it to the DC boost bus under the drive of the DC boost drive module.

10. The feedback protection circuit of an inverter according to claim 9, characterized in that: The feedback protection circuit of the inverter also includes at least one inverter circuit, which is respectively connected to the DC boost bus, the inverter drive module and the target AC bus, and is used to invert the second DC voltage into the target AC voltage and output it to the target AC bus under the control of the inverter drive module.

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