A grid-connected inverter control circuit with integrated inductor

Abstract

This invention discloses a grid-connected inverter control circuit with an integrated inductor, relating to the field of grid-connected control technology. It includes a DC module that receives DC power and performs low-voltage and overcurrent detection. When there is no low voltage, the conversion control module performs alternating boost and inversion processing and connects to the grid through the grid module. During overcurrent, the conversion control module, in conjunction with the inverter module, performs dual-path boost and inversion processing and connects to the grid through the grid module. When a voltage drop occurs in the AC power supplied by the AC module to the grid module, the inverter module can compensate for the AC power supply by changing the power transmission path. During low voltage, the conversion control module can superimpose and invert the boosted power from both paths to maintain the required power for grid connection. This grid-connected inverter control circuit with an integrated inductor can change the power supply state according to the DC power voltage and the voltage drop state of the AC module, maintaining grid stability and improving power supply efficiency.

Description

Technical Field

[0001] This invention relates to the field of grid-connected control technology, specifically to a grid-connected inverter control circuit with an integrated inductor. Background Technology

[0002] A grid-connected inverter is a device that converts input DC power into AC power and outputs it to the power grid. With increasingly stringent requirements for grid-connected systems, power supply reliability has become a major concern. In existing technologies, to increase the voltage regulation gain of the DC section, a boost circuit composed of a coupling transformer is generally used for step-up regulation, followed by inversion by the inverter to keep the voltage in phase with the grid voltage. However, the boost circuit composed of the coupling transformer is large in size and weight, and leakage inductance may cause voltage spikes, requiring the addition of absorption circuits. Furthermore, the gain effect depends on the turns ratio of the transformer. In addition, it cannot perform auxiliary voltage compensation based on the DC conversion operating state, resulting in low functionality. Moreover, the range of input DC power is small, and the input voltage width is narrow, thus requiring improvement. Summary of the Invention

[0003] This invention provides a grid-connected inverter control circuit with an integrated inductor to solve the problems mentioned in the background art.

[0004] According to an embodiment of the present invention, a grid-connected inverter control circuit with an integrated inductor is provided, comprising: The DC module is used to receive DC power, sample the voltage of the DC power, compare the voltage signal with a low voltage threshold and detect low voltage. When the voltage is low, it outputs a first detection signal. It also samples the current of the DC power, compares the current signal with an overcurrent threshold and detects overcurrent. When the current is overcurrent, it outputs a second detection signal. The microcontroller module, connected to the DC module, the conversion control module, and the inverter module, is used to control the conversion control module to perform alternating boost and inversion operations when no first detection signal is received. When no first detection signal is received and a second detection signal is received, or when a voltage drop occurs in the AC module, the microcontroller module is controlled to perform dual-path boost and inversion, and the inverter module is controlled to invert the boosted power of one path. When a voltage drop occurs in the AC module, the microcontroller module is controlled to perform power compensation for the AC module. When the first detection signal is received, the microcontroller module is controlled to perform dual-path boost, and the boosted power is superimposed and inverted. The inverter module is controlled to perform power compensation processing for the AC module. The conversion control module is connected to the DC module and is used to boost the voltage by storing and discharging energy through capacitors and inductors. It performs alternating voltage boosting, dual voltage boosting, or dual voltage boosting and superposition of energy for DC power. It performs inversion processing on the output energy after alternating voltage boosting, the energy after boosting one of the dual voltage boosting channels, or the energy after superposition of energy. The inverter module is connected to the conversion control module, the grid module, and the AC module. It is used to store the electrical energy output by the conversion control module after boosting, invert the stored electrical energy and supply power to the grid module. When it does not receive electrical energy output from the conversion control module, it rectifies and stores the AC electrical energy output from the AC module. When a voltage drop occurs in the AC module, it changes the transmission path of the electrical energy output after inversion and compensates the AC module for electrical energy. The AC module is used to connect to AC power, isolate and transform the power transmitted by the inverter module, and compensate for the AC power. The grid module, connected to the conversion control module and the AC module, is used to connect AC power, power transmitted by the inverter module, or power output from the inverter of the transformer control module to the grid.

[0005] As a further embodiment of the present invention: the DC module includes a DC interface; the conversion control module includes a first diode, a first inductor, a first capacitor, a sixth inductor, a second diode, a second power transistor, a fourth diode, and a first power transistor; the microcontroller module includes a first controller; Preferably, the first end of the DC interface is connected to the anode of the first diode and connected to one end of the first capacitor and the anode of the second diode through the first inductor. The cathode of the first diode is connected to the other end of the first capacitor and connected to the cathode of the second diode, the drain of the first power transistor, and the drain of the second power transistor through the sixth inductor. The source of the second power transistor is connected to the anode of the fourth diode. The source of the first power transistor is grounded. The gate of the first power transistor and the gate of the second power transistor are respectively connected to the IO1 and IO2 terminals of the first controller.

[0006] As a further embodiment of the present invention: the conversion control module further includes a third diode, a fifth diode, a second inductor, a second capacitor, a third inductor, an eighth diode, a sixth diode, a fifth power transistor, and a fourth power transistor; Preferably, the anode of the third diode is connected to the first terminal of the DC interface, the cathode of the third diode is connected to the anode of the fifth diode and the cathode of the fourth diode, and is connected to the anode of the sixth diode and one end of the second capacitor through the second inductor. The other end of the second capacitor is connected to the cathode of the fifth diode, and is connected to the cathode of the sixth diode, the drain of the fourth power transistor, the drain of the fifth power transistor, and the anode of the eighth diode through the third inductor. The source of the fourth power transistor is connected to the cathode of the second diode, the source of the fifth power transistor is connected to the source of the first power transistor, and the gates of the fourth power transistor and the fifth power transistor are respectively connected to the IO4 and IO5 terminals of the first controller.

[0007] As a further embodiment of the present invention: the conversion control module further includes a first inverter, a fifth inductor, and a sixth capacitor; the power grid module includes an AC power grid; Preferably, the first input terminal of the first inverter is connected to the cathode of the eighth diode and connected to the second input terminal of the first inverter and the source of the fifth power transistor through the third capacitor. The first output terminal of the first inverter is connected to one end of the sixth capacitor and the first terminal of the AC power grid through the fifth inductor. The other end of the sixth capacitor is connected to the second terminal of the AC power grid and the second output terminal of the first inverter. The control terminal of the first inverter is connected to the IO6 terminal of the first controller.

[0008] As a further embodiment of the present invention: the inverter module includes a seventh diode, a third power transistor, a fourth capacitor, a second inverter, a fourth inductor, a fifth capacitor, and a first relay; Preferably, the anode of the seventh diode is connected to the source of the third power transistor, the drain of the third power transistor is connected to the cathode of the second diode, the cathode of the seventh diode is connected to the first input terminal of the second inverter and connected to the second input terminal of the second inverter and the source of the fifth power transistor through the fourth capacitor, the first output terminal of the second inverter is connected to terminal 5 of the first relay and connected to terminal 1 of the first relay through the fourth inductor and connected to the second output terminal of the second inverter, terminal 3 and terminal 7 of the first relay through the fifth capacitor, the terminal 2 and terminal 4 of the first relay are respectively connected to the first and second terminals of the AC power grid, and the control terminal of the second inverter and the control terminal of the first relay are respectively connected to the IO7 and IO8 terminals of the first controller.

[0009] As a further embodiment of the present invention: the DC module further includes a first resistor, a second resistor, a third resistor, a current detection device, a first comparator, and a first reference power supply; Preferably, one end of the first resistor is connected to the first terminal of the DC interface, the other end of the first resistor is connected to the inverting terminal of the first comparator and is connected to one end of the third resistor, the second input terminal of the current detection device and the ground terminal through the second resistor, the second terminal of the DC interface is connected to the other end of the third resistor and the first input terminal of the current detection device, the non-inverting terminal of the first comparator is connected to the first reference power supply, and the output terminal of the first comparator and the output terminal of the current detection device are respectively connected to the IO9 terminal and the IO10 terminal of the first controller.

[0010] As a further embodiment of the present invention: the AC module includes an AC interface and a first transformer; Preferably, the first end of the AC interface is connected to the first end of the secondary side of the first transformer, the 9th and 6th ends of the first relay, the second end of the secondary side of the first transformer is connected to the 10th end of the first relay and the first end of the power grid interface, the second end of the AC interface is connected to the second end of the power grid interface and the second end of the primary side of the first transformer, and the first end of the primary side of the first transformer is connected to the 8th end of the first relay.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: The grid-connected inverter control circuit of the present invention, which integrates an inductor, can be connected to DC power by a DC module and perform low voltage and overcurrent detection based on low voltage and overcurrent thresholds. When there is no low voltage, the conversion control module performs alternating boost and inversion processing and connects to the grid through the grid module. When there is an overcurrent, the conversion control module cooperates with the inverter module to perform dual-path boost and inversion processing and connects to the grid through the grid module. When there is a voltage drop in the AC power supplied by the AC module to the grid module, the inverter module can perform power compensation processing for the AC module by changing the power transmission path. When there is low voltage, the conversion control module can perform superposition and inversion processing of the dual-path boosted power to maintain the power required for grid connection. The power supply state can be changed according to the voltage magnitude of the DC power and the voltage drop state of the AC module to maintain the grid stability of the grid module and improve the power supply efficiency. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic block diagram of a grid-connected inverter control circuit with an integrated inductor provided in an embodiment of the present invention.

[0014] Figure 2 A circuit diagram of a grid-connected inverter control circuit with an integrated inductor provided in an embodiment of the present invention.

[0015] Figure 3 A circuit diagram of a DC module provided for an embodiment of the present invention.

[0016] Figure 4 A circuit diagram of an AC module provided in an embodiment of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In one embodiment, see Figure 1 A grid-connected inverter control circuit with an integrated inductor, comprising: DC module 1 is used to receive DC power, sample the voltage of DC power, compare the voltage signal with a low voltage threshold and detect low voltage. When the voltage is low, it outputs a first detection signal. It also samples the current of DC power, compares the current signal with an overcurrent threshold and detects overcurrent. When the current is overcurrent, it outputs a second detection signal. The microcontroller module 2 is connected to the DC module 1, the conversion control module 3, and the inverter module 4. When the first detection signal is not received, it controls the conversion control module 3 to perform alternating boost and inversion operations. When the first detection signal is not received and the second detection signal is received, or when the AC module 5 experiences a voltage drop, it controls the conversion control module 3 to perform dual-path boost and inversion and controls the inverter module 4 to invert the boosted power. When the AC module 5 experiences a voltage drop, it controls the inverter module 4 to perform power compensation for the AC module 5. When the first detection signal is received, it controls the conversion control module 3 to perform dual-path boost and superimpose and invert the boosted power, and controls the inverter module 4 to perform power compensation for the AC module 5. The conversion control module 3 is connected to the DC module 1 and is used to boost the DC power through energy storage and discharge by capacitors and inductors. It performs alternating boost, dual boost, or dual boost and superposition of DC power, and performs inversion on the power output after alternating boost, the power after boosting one of the dual boost channels, or the power after superposition of power. Inverter module 4 is connected to conversion control module 3, grid module 6 and AC module 5. It is used to store the electrical energy output by conversion control module 3 after boosting, invert the stored electrical energy and supply power to grid module 6. When it does not receive electrical energy output by conversion control module 3, it rectifies and stores the AC energy output by AC module 5. When there is a voltage drop in AC module 5, it changes the transmission path of the electrical energy output after inversion and compensates the AC module 5 for the electrical energy. AC module 5 is used to connect to AC power, isolate and transform the power transmitted by inverter module 4, and compensate the AC power. The grid module 6 is connected to the conversion control module 3 and the AC module 5, and is used to perform grid connection processing on AC power, power transmitted by the inverter module 4, or power output from the inverter of the transformer control module.

[0019] In a specific embodiment, the DC module 1 can be a DC circuit composed of a DC interface, resistors, comparators, and a current detection device. It can receive DC power, sample the DC power voltage and current, compare the sampled voltage signal with a set low-voltage threshold, and perform voltage conversion and signal amplification on the sampled current signal before comparing it with a set overcurrent threshold. The microcontroller module 2 can be a microcontroller circuit composed of a single-chip microcomputer, integrating arithmetic logic unit (ALU), controller, memory, and input / output devices, etc., to realize functions such as signal processing, data storage, module control, and timing control. The conversion control module 3 can be a conversion control circuit composed of field-effect transistors (FETs), inductors, capacitors, and inverters, and can consist of two sets of capacitors, inductors, diodes, and FETs. The voltage is boosted by controlling the conduction state of the field-effect transistors, allowing the two groups to alternately boost or boost both voltages simultaneously. The output power after boosting both voltages can also be inverted on one side and transmitted to inverter module 4 or superimposed on the other. Inverter module 4 can be an inverter circuit composed of field-effect transistors, capacitors, bidirectional inverters, relays, etc., capable of power transmission, energy storage, rectification, and inversion, switching power transmission paths and supplying power to AC module 5 or grid module 6. AC module 5 can be an AC circuit composed of an AC interface and a transformer, receiving AC power, transforming the output power of inverter module 4, and compensating for the AC power. Grid module 6 can use an AC grid for power reception, grid connection, and distribution.

[0020] In this embodiment, please refer to Figure 2 , Figure 3 and Figure 4 The DC module 1 includes a DC interface; the conversion control module 3 includes a first diode D1, a first inductor L1, a first capacitor C1, a sixth inductor L6, a second diode D2, a second power transistor Q2, a fourth diode D4, and a first power transistor Q1; the microcontroller module 2 includes a first controller U1; Specifically, the first end of the DC interface is connected to the anode of the first diode D1 and to one end of the first capacitor C1 and the anode of the second diode D2 through the first inductor L1. The cathode of the first diode D1 is connected to the other end of the first capacitor C1 and to the cathode of the second diode D2, the drain of the first power transistor Q1 and the drain of the second power transistor Q2 through the sixth inductor L6. The source of the second power transistor Q2 is connected to the anode of the fourth diode D4. The source of the first power transistor Q1 is grounded. The gate of the first power transistor Q1 and the gate of the second power transistor Q2 are respectively connected to the IO1 and IO2 terminals of the first controller U1.

[0021] In a specific embodiment, the aforementioned DC interface can be connected to DC power, which can be provided by DC batteries or photovoltaic cells, but is not limited to DC batteries or photovoltaic cells; the aforementioned first power transistor Q1 and second power transistor Q2 can both be N-channel field-effect transistors. The first power transistor Q1 controls the first inductor L1, the first capacitor C1 and the sixth inductor L6 to store and discharge energy, and works with the first diode D1 and the second diode D2 to perform voltage boosting. The second power transistor Q2 controls the power transmission to complete the power superposition; the aforementioned first controller U1 can be an STM32 microcontroller.

[0022] Furthermore, the conversion control module 3 also includes a third diode D3, a fifth diode D5, a second inductor L2, a second capacitor C2, a third inductor L3, an eighth diode D8, a sixth diode D6, a fifth power transistor Q5, and a fourth power transistor Q4; Specifically, the anode of the third diode D3 is connected to the first terminal of the DC interface, the cathode of the third diode D3 is connected to the anode of the fifth diode D5 and the cathode of the fourth diode D4, and is connected to the anode of the sixth diode D6 and one end of the second capacitor C2 through the second inductor L2. The other end of the second capacitor C2 is connected to the cathode of the fifth diode D5, and is connected to the cathode of the sixth diode D6, the drain of the fourth power transistor Q4, the drain of the fifth power transistor Q5 and the anode of the eighth diode D8 through the third inductor L3. The source of the fourth power transistor Q4 is connected to the cathode of the second diode D2, the source of the fifth power transistor Q5 is connected to the source of the first power transistor Q1, and the gate of the fourth power transistor Q4 and the gate of the fifth power transistor Q5 are respectively connected to the IO4 and IO5 terminals of the first controller U1.

[0023] In a specific embodiment, both the fourth power transistor Q4 and the fifth power transistor Q5 can be N-channel MOSFETs. The fifth power transistor Q5 can control the second inductor L2, the second capacitor C2, and the third inductor L3 to store and discharge energy, and cooperate with the fifth diode D5 and the sixth diode D6 to perform voltage boosting. The second power transistor Q2 can control the second inductor L2, the second capacitor C2, and the third inductor L3 to store and discharge energy synchronously with the first inductor L1, the first capacitor C1, and the sixth inductor L6.

[0024] Furthermore, the conversion control module 3 also includes a first inverter T1, a fifth inductor L5, and a sixth capacitor C6; the power grid module 6 includes an AC power grid; Specifically, the first input terminal of the first inverter T1 is connected to the cathode of the eighth diode D8 and is connected to the second input terminal of the first inverter T1 and the source of the fifth power transistor Q5 through the third capacitor. The first output terminal of the first inverter T1 is connected to one end of the sixth capacitor C6 and the first end of the AC power grid through the fifth inductor L5. The other end of the sixth capacitor C6 is connected to the second end of the AC power grid and the second output terminal of the first inverter T1. The control terminal of the first inverter T1 is connected to the IO6 terminal of the first controller U1.

[0025] In a specific embodiment, the first inverter T1 can be composed of four IGBTs and driven by four sets of drive signals provided by the IO6 terminal of the first controller U1 to perform inverter processing.

[0026] Furthermore, the inverter module 4 includes a seventh diode D7, a third power transistor Q3, a fourth capacitor C4, a second inverter T2, a fourth inductor L4, a fifth capacitor C5, and a first relay K1; Specifically, the anode of the seventh diode D7 is connected to the source of the third power transistor Q3, the drain of the third power transistor Q3 is connected to the cathode of the second diode D2, the cathode of the seventh diode D7 is connected to the first input terminal of the second inverter T2 and is connected to the second input terminal of the second inverter T2 and the source of the fifth power transistor Q5 through the fourth capacitor C4, the first output terminal of the second inverter T2 is connected to terminal 5 of the first relay K1 and is connected to terminal 1 of the first relay K1 through the fourth inductor L4 and is connected to the second output terminal of the second inverter T2, terminal 3 and terminal 7 of the first relay K1 through the fifth capacitor C5, terminal 2 and terminal 4 of the first relay K1 are connected to the first and second terminals of the AC power grid, respectively, and the control terminal of the second inverter T2 and the control terminal of the first relay K1 are connected to the IO7 and IO8 terminals of the first controller U1, respectively.

[0027] In a specific embodiment, the third power transistor Q3 can be an N-channel MOSFET; the second inverter T2 can be composed of four IGBTs connected in parallel with diodes for bidirectional power regulation, i.e., inversion and rectification; the first relay K1 consists of a magnetic coil and a relay switch. The relay switch is a five-pole single-throw switch, controlled by the magnetic coil through magnetic attraction. Terminals 1 and 2, 3 and 4, 5 and 6, 7 and 8, and 9 and 10 of the first relay K1 are all relay switches, and terminals 1 and 2, 3 and 4, and 9 and 10 are normally closed switches, while terminals 5 and 6, and 7 and 8 are normally open switches.

[0028] Furthermore, the DC module 1 also includes a first resistor R1, a second resistor R2, a third resistor R3, a current detection device, a first comparator A1, and a first reference power supply VF1; Specifically, one end of the first resistor R1 is connected to the first terminal of the DC interface, the other end of the first resistor R1 is connected to the inverting terminal of the first comparator A1 and is connected to one end of the third resistor R3, the second input terminal of the current detection device and the ground terminal through the second resistor R2. The second terminal of the DC interface is connected to the other end of the third resistor R3 and the first input terminal of the current detection device. The non-inverting terminal of the first comparator A1 is connected to the first reference power supply VF1. The output terminal of the first comparator A1 and the output terminal of the current detection device are respectively connected to the IO9 terminal and the IO10 terminal of the first controller U1.

[0029] In a specific embodiment, the first comparator A1 can be an LM358 comparator, and the first reference power supply VF1 sets a voltage threshold, which is the minimum voltage value required by the conversion control module 3 when performing alternating boost operation. The current detection device can be composed of a signal conversion amplification circuit and an overcurrent detection circuit. The signal conversion amplification circuit can be composed of resistors, capacitors and operational amplifiers, which convert the current signal sampled by the third resistor R3 into a voltage signal and amplify it. The overcurrent detection circuit can be composed of a comparator and a reference power supply, which provides an overcurrent threshold. The comparator compares the amplified signal with the overcurrent threshold, and if the amplified signal is greater than the overcurrent threshold, then it is an overcurrent.

[0030] Furthermore, the AC module 5 includes an AC interface and a first transformer B1; Specifically, the first end of the AC interface is connected to the first end of the secondary side of the first transformer B1, and terminals 9 and 6 of the first relay K1. The second end of the secondary side of the first transformer B1 is connected to terminal 10 of the first relay K1 and the first end of the power grid interface. The second end of the AC interface is connected to the second end of the power grid interface and the second end of the primary side of the first transformer B1. The first end of the primary side of the first transformer B1 is connected to terminal 8 of the first relay K1.

[0031] In a specific embodiment, the aforementioned AC interface is connected to AC power, which may be provided by a generator but is not limited to a generator; the aforementioned first transformer B1 may be a high-frequency transformer.

[0032] The working principle of the grid-connected inverter control circuit with integrated inductor of the present invention is as follows: DC power is connected through a DC interface. The voltage of the DC power is sampled by the first resistor R1 and the second resistor R2, and the current is sampled by the third resistor R3. When the sampled voltage signal is greater than the voltage threshold set by the first reference power supply VF1, the first comparator A1 outputs a low level. At this time, the IO1 and IO5 terminals of the first controller U1 alternately control the conduction state of the first power transistor Q1 and the fifth power transistor Q5. The IO6 terminal of the first controller U1 controls the first inverter T1 to perform inversion, so that the first power transistor Q1, together with the first diode D1, the first inductor L1, the first capacitor C1, the second diode D2, and the sixth inductor L6, performs boost processing. Specifically, by controlling the first inductor... Inductor L1, capacitor C1, and inductor L6 store and discharge energy, which is then superimposed with DC power to achieve boost control. Similarly, power transistor Q5, in conjunction with diodes D5, D3, L2, C2, L3, and D6, boosts the voltage. The output power after alternating boosting is inverted and filtered by inverter T1, inductor L5, and capacitor C6 before being fed into the AC grid. The current detection device converts and amplifies the sampled current signal and performs overcurrent detection. When an overcurrent occurs, the current detection device outputs a second detection signal, which is received by the IO10 terminal of the first controller U1. The first controller U1 will then stop alternating control. U1 independently controls the conduction states of the first power transistor Q1 and the fifth power transistor Q5, achieving dual-path boost processing and current splitting. The IO3 terminal of the first controller U1 controls the conduction of the third power transistor Q3, and the IO7 terminal of the first controller U1 controls the second inverter T2 to perform inversion. This ensures that the power output from the boosted portion of the first power transistor Q1 is inverted and filtered by the second inverter T2, the fourth inductor L4, and the fifth capacitor C5, and then fed into the AC power grid via terminals 1 to 4 of the first relay K1. The power output from the boosted portion of the fifth power transistor Q5 is processed by the first inverter T1, the fifth inductor L5, and the sixth capacitor C6 before being fed into the grid. Simultaneously, AC power is connected to the AC interface and transmitted to the AC grid through terminals 9 and 10 of the first relay K1. If this... When a voltage drop occurs in the AC power grid, the IO8 terminal of the first controller U1 provides a high level to the control terminal of the first relay K1, causing the first relay K1 to change its switching state. Terminals 1 and 2, 3 and 4, and 9 and 10 are all disconnected, while terminals 5 and 6, and 7 and 8 are closed. This allows the electrical energy output after inverter regulation by the second inverter T2 to undergo electrical energy compensation processing by the first transformer B1. When the voltage signal is lower than the voltage threshold, the first comparator A1 outputs a first detection signal, which is received by the IO9 terminal of the first controller U1. The IO1, IO2, and IO4 terminals of the first controller U1 control the conduction states of the first power transistor Q1, the second power transistor Q2, and the fourth power transistor Q4.The dual-channel boosted power is superimposed through the second power transistor Q2 and the fourth diode D4, then processed by the first inverter T1, the fifth inductor L5, and the sixth capacitor C6 before being connected to the grid. Simultaneously, the first controller U1 controls the first relay K1 to operate, causing the second inverter T2 to rectify the AC power, which is then stored in the fourth capacitor C4. This allows the fourth capacitor C4 to invert the AC power through the second inverter T2 when a voltage drop occurs, and then compensate for the AC power through the first transformer B1.

[0033] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0034] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An integrated inductor grid-connected inverter control circuit, characterized by, The circuit includes: The DC module is used to receive DC power, sample the voltage of the DC power, compare the voltage signal with a low voltage threshold and detect low voltage. When the voltage is low, it outputs a first detection signal. It also samples the current of the DC power, compares the current signal with an overcurrent threshold and detects overcurrent. When the current is overcurrent, it outputs a second detection signal. The microcontroller module, connected to the DC module, the conversion control module, and the inverter module, is used to control the conversion control module to perform alternating boost and inversion operations when no first detection signal is received. When no first detection signal is received and a second detection signal is received, or when a voltage drop occurs in the AC module, the microcontroller module is controlled to perform dual-path boost and inversion, and the inverter module is controlled to invert the boosted power of one path. When a voltage drop occurs in the AC module, the microcontroller module is controlled to perform power compensation for the AC module. When the first detection signal is received, the microcontroller module is controlled to perform dual-path boost, and the boosted power is superimposed and inverted. The inverter module is controlled to perform power compensation processing for the AC module. The conversion control module is connected to the DC module and is used to boost the voltage by storing and discharging energy through capacitors and inductors. It performs alternating voltage boosting, dual voltage boosting, or dual voltage boosting and superposition of energy for DC power. It performs inversion processing on the output energy after alternating voltage boosting, the energy after boosting one of the dual voltage boosting channels, or the energy after superposition of energy. The inverter module is connected to the conversion control module, the grid module, and the AC module. It is used to store the electrical energy output by the conversion control module after boosting, invert the stored electrical energy and supply power to the grid module. When it does not receive electrical energy output from the conversion control module, it rectifies and stores the AC electrical energy output from the AC module. When a voltage drop occurs in the AC module, it changes the transmission path of the electrical energy output after inversion and compensates the AC module for electrical energy. The AC module is used to connect to AC power, isolate and transform the power transmitted by the inverter module, and compensate for the AC power. The grid module, connected to the conversion control module and the AC module, is used to connect AC power, power transmitted by the inverter module, or power output from the inverter of the transformer control module to the grid.

2. The integrated inductor grid-tie inverter control circuit of claim 1, wherein, The DC module includes a DC interface; the conversion control module includes a first diode, a first inductor, a first capacitor, a sixth inductor, a second diode, a second power transistor, a fourth diode, and a first power transistor; the microcontroller module includes a first controller; The first end of the DC interface is connected to the anode of the first diode and is connected to one end of the first capacitor and the anode of the second diode through the first inductor. The cathode of the first diode is connected to the other end of the first capacitor and is connected to the cathode of the second diode, the drain of the first power transistor, and the drain of the second power transistor through the sixth inductor. The source of the second power transistor is connected to the anode of the fourth diode. The source of the first power transistor is grounded. The gate of the first power transistor and the gate of the second power transistor are respectively connected to the IO1 and IO2 terminals of the first controller.

3. The integrated inductor grid-tie inverter control circuit of claim 2, wherein, The conversion control module also includes a third diode, a fifth diode, a second inductor, a second capacitor, a third inductor, an eighth diode, a sixth diode, a fifth power transistor, and a fourth power transistor; The anode of the third diode is connected to the first terminal of the DC interface. The cathode of the third diode is connected to the anode of the fifth diode and the cathode of the fourth diode, and is connected to the anode of the sixth diode and one end of the second capacitor through the second inductor. The other end of the second capacitor is connected to the cathode of the fifth diode, and is connected to the cathode of the sixth diode, the drain of the fourth power transistor, the drain of the fifth power transistor, and the anode of the eighth diode through the third inductor. The source of the fourth power transistor is connected to the cathode of the second diode. The source of the fifth power transistor is connected to the source of the first power transistor. The gates of the fourth power transistor and the fifth power transistor are respectively connected to the IO4 and IO5 terminals of the first controller.

4. The integrated inductor grid-tie inverter control circuit of claim 3, wherein, The conversion control module also includes a first inverter, a fifth inductor, and a sixth capacitor; the power grid module includes an AC power grid. The first input terminal of the first inverter is connected to the cathode of the eighth diode and is connected to the second input terminal of the first inverter and the source of the fifth power transistor through the third capacitor. The first output terminal of the first inverter is connected to one end of the sixth capacitor and the first end of the AC power grid through the fifth inductor. The other end of the sixth capacitor is connected to the second end of the AC power grid and the second output terminal of the first inverter. The control terminal of the first inverter is connected to the IO6 terminal of the first controller.

5. The integrated inductor grid-tie inverter control circuit of claim 4, wherein, The inverter module includes a seventh diode, a third power transistor, a fourth capacitor, a second inverter, a fourth inductor, a fifth capacitor, and a first relay; The anode of the seventh diode is connected to the source of the third power transistor, the drain of the third power transistor is connected to the cathode of the second diode, the cathode of the seventh diode is connected to the first input terminal of the second inverter and connected to the second input terminal of the second inverter and the source of the fifth power transistor through the fourth capacitor, the first output terminal of the second inverter is connected to terminal 5 of the first relay and connected to terminal 1 of the first relay through the fourth inductor and connected to the second output terminal of the second inverter, terminal 3 and terminal 7 of the first relay through the fifth capacitor, the terminal 2 and terminal 4 of the first relay are respectively connected to the first and second terminals of the AC power grid, and the control terminal of the second inverter and the control terminal of the first relay are respectively connected to the IO7 and IO8 terminals of the first controller.

6. The integrated inductor grid-tie inverter control circuit of claim 5, wherein, The DC module also includes a first resistor, a second resistor, a third resistor, a current detection device, a first comparator, and a first reference power supply; One end of the first resistor is connected to the first end of the DC interface, and the other end of the first resistor is connected to the inverting input of the first comparator and is connected to one end of the third resistor, the second input of the current detection device and the ground through the second resistor. The second end of the DC interface is connected to the other end of the third resistor and the first input of the current detection device. The non-inverting input of the first comparator is connected to the first reference power supply. The output of the first comparator and the output of the current detection device are respectively connected to the IO9 and IO10 terminals of the first controller.

7. The integrated inductor grid-tie inverter control circuit of claim 6, wherein, The AC module includes an AC interface and a first transformer; The first end of the AC interface is connected to the first end of the secondary side of the first transformer, the 9th and 6th ends of the first relay, the second end of the secondary side of the first transformer is connected to the 10th end of the first relay and the first end of the power grid interface, the second end of the AC interface is connected to the second end of the power grid interface and the second end of the primary side of the first transformer, and the first end of the primary side of the first transformer is connected to the 8th end of the first relay.

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