Photovoltaic grid-connected inverter based on disturbance tracking

Abstract

The invention discloses a photovoltaic grid-connected inverter based on disturbance tracking, which relates to the technical field of new energy power electronics and comprises a first direct-current power supply, a second direct-current power supply, a first main control module, a second main control module, a first main power loop, a second main power loop, an AC-AC conversion circuit, an isolation transformer and an auxiliary power supply, the first direct-current power supply is connected with the first main power loop, and the first main power loop is connected with the first main control module; the second direct-current power supply is connected with a second main power loop, and the second main power loop is connected with a second main control module; the output end of the first main power loop and the output end of the second main power loop are connected with an AC-AC conversion circuit, and the output end of the AC-AC conversion circuit is connected with an isolation transformer. According to the invention, disturbance tracking is carried out on power change by arranging two groups of inverters, the photovoltaic inverters are ensured to work at the maximum power point, and the overall system performance and economic benefits are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy power electronics, and in particular to a photovoltaic grid-connected inverter based on disturbance tracking. Background Art

[0002] Small photovoltaic power generation grid-connected systems are mainly composed of direct current-to-direct current (DC / DC) and direct current-to-alternating current (DC / AC) conversion circuits and their controllers. Conversion circuits are also called converters, circuit topologies or topological structures. DC / AC circuit topologies usually use bidirectional full-bridge inverter circuits. Since four power switch tubes and their body diodes are used, they are also called bidirectional H4 topologies. Figure 1 As shown. H4 inverter topology has outstanding advantages such as simple topology structure and mature control method, and is widely used in industrial and civil inverters. The DC-DC conversion circuit uses Boost topology to make

[0003] In traditional MPPT, the P&O algorithm is the simplest and has good convergence. However, this algorithm has serious shortcomings. When the light changes slightly or the environmental conditions are constant, the P&O algorithm can maintain near the maximum power point. However, once the light conditions change, the fixed disturbance amplitude may cause the system to be unable to respond in time, resulting in deviation from the tracking direction.

[0004] Traditional P&O algorithms do not take into account the impact of dynamic boundary conditions, which results in the algorithm deviating from its normal tracking trajectory in certain extreme cases (such as sudden drop in light intensity, load changes, etc.), affecting the overall tracking efficiency. Summary of the invention

[0005] The technical problem to be solved by the present invention is to solve the deficiencies in the prior art and design a photovoltaic grid-connected inverter based on disturbance tracking. The present invention can reduce steady-state oscillations and reduce the steady-state oscillations of the photovoltaic system when tracking the maximum power point by dynamically changing the disturbance size, thereby improving the stability of the system and ensuring that the photovoltaic array operates at a higher efficiency near the maximum power point.

[0006] The technical solution adopted by the present invention is: a photovoltaic grid-connected inverter based on disturbance tracking, comprising:

[0007] A first DC power supply, a second DC power supply, a first main control module, a second main control module, a first main power circuit, a second main power circuit, an AC-AC conversion circuit, an isolation transformer and an auxiliary power supply;

[0008] The first DC power supply is connected to the first main power circuit, and the first main power circuit is connected to the first main control module;

[0009] The second DC power supply is connected to the second main power circuit, and the second main power circuit is connected to the second main control module;

[0010] The output ends of the first main power circuit and the second main power circuit are connected to an AC-AC conversion circuit, and the output end of the AC-AC conversion circuit is connected to an isolation transformer;

[0011] The auxiliary power supply is powered by the first DC power supply, the second DC power supply, the first main control module, the second main control module, the first main power circuit, and the second main power circuit.

[0012] As a further technical solution of the present invention, the first main control module includes a first SVPWM generation module, a first PI adjustment module, a first sampling calculation module and a first GPIO module, the first sampling calculation module is connected to the output end of the first power circuit; the output end of the first sampling calculation module is connected to the first PI adjustment module, the output end of the first PI adjustment module is connected to the first SVPWM generation module, and the output end of the first SVPWM generation module is connected to the first main power circuit;

[0013] The second main control module includes a second SVPWM generation module, a second PI regulation module, a second sampling calculation module and a second GPIO module. The second sampling calculation module is connected to the output end of the second power circuit; the output end of the second sampling calculation module is connected to the second PI regulation module, the output end of the second PI regulation module is connected to the second SVPWM generation module, and the output end of the second SVPWM generation module is connected to the second main power circuit.

[0014] As a further technical solution of the present invention, both the first main control module and the second main control module adopt STM32F334 model MCU.

[0015] As a further technical solution of the present invention, the first sampling and calculation module includes a current sampling and amplifying circuit and a voltage sampling and amplifying circuit, wherein the current sampling and amplifying circuit adopts an INA199A2 amplifier, and the voltage sampling circuit adopts a GS8552 amplifier.

[0016] As a further technical solution of the present invention, the auxiliary power supply includes three voltage circuits of 10V, 5V and 3.3V, wherein the 10V power supply module adopts the XL7005A chip, the 5V power supply module adopts the MP2451 chip, and the 3.3V power supply module adopts the RT9193 chip.

[0017] As a further technical solution of the present invention, the first main power circuit adopts a single-phase inverter DC-AC circuit and a BOOST boost circuit; the output end of the BOOST boost circuit is connected to the single-phase inverter DC-AC circuit after being filtered by a low-pass filter.

[0018] As a further technical solution of the present invention, the BOOST boost circuit adopts an N-channel MOS tube of BSC123N10LS, and the low-pass filter selects a second-order LC filter.

[0019] As a further technical solution of the present invention, the single-phase inverter DC-AC circuit is a drive module of model EG3112.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention uses two sets of inverters to work in parallel, and uses a dual PID algorithm to feedback control the output line voltage of the two inverters according to the first main control module and the second main control module. By setting two sets of inverters, disturbance tracking of power changes is achieved to ensure that the photovoltaic inverter works at the maximum power point, avoid divergence, and ensure the stable operation of the photovoltaic system under different operating conditions. This mechanism effectively reduces output fluctuations when the light changes rapidly.

[0022] 2. The present invention realizes dynamic change of disturbance size by setting two sets of inverters in parallel to reduce steady-state oscillation, thereby reducing the possibility of photovoltaic system disturbance and loss of tracking direction of observation-based (P&O) maximum power point tracking (MPPT); dynamic boundary conditions are introduced into the maximum power point tracking algorithm to ensure that the algorithm does not deviate from its tracking trajectory.

[0023] 3. The present invention can reduce steady-state oscillations by dynamically changing the disturbance size, thereby reducing the steady-state oscillations of the photovoltaic system when tracking the maximum power point, improving the stability of the system, ensuring that the photovoltaic array operates with higher efficiency near the maximum power point, improving the energy collection efficiency of the photovoltaic system in various working environments, and reducing the energy loss caused by tracking failure, thereby improving the overall system performance and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a control structure diagram of a photovoltaic grid-connected inverter based on disturbance tracking proposed by the present invention;

[0025] Figure 2 It is a principle structure diagram of a photovoltaic grid-connected inverter based on disturbance tracking proposed by the present invention;

[0026] Figure 3 It is a framework diagram of the photovoltaic grid-connected inverter P&O algorithm based on disturbance tracking proposed by the present invention;

[0027] Figure 4 It is a voltage sampling circuit diagram proposed by the present invention;

[0028] Figure 5 It is the current sampling circuit diagram proposed by the present invention;

[0029] Figure 6 It is the circuit diagram of the 10V power supply module proposed by the present invention;

[0030] Figure 7 It is the circuit diagram of the 5V power supply module proposed by the present invention;

[0031] Figure 8 It is the circuit diagram of the 3.3V power supply module proposed by the present invention;

[0032] Fig. 9 It is the circuit diagram of the BOOST boost circuit proposed by the present invention;

[0033] Fig.10 It is a single-phase inverter DC-AC circuit diagram proposed by the present invention; DETAILED DESCRIPTION

[0034] The specific implementation of the present invention is described below in conjunction with the accompanying drawings and embodiments:

[0035] It should be noted that the structures, colors, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them, and are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0036] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0037] like Figure 1 As shown, the present invention provides a photovoltaic grid-connected inverter based on disturbance tracking, comprising:

[0038] A first DC power supply, a second DC power supply, a first main control module, a second main control module, a first main power circuit, a second main power circuit, an AC-AC conversion circuit, an isolation transformer and an auxiliary power supply;

[0039] The first DC power supply is connected to the first main power circuit, and the first main power circuit is connected to the first main control module;

[0040] The second DC power supply is connected to the second main power circuit, and the second main power circuit is connected to the second main control module;

[0041] The output ends of the first main power circuit and the second main power circuit are connected to an AC-AC conversion circuit, and the output end of the AC-AC conversion circuit is connected to an isolation transformer;

[0042] The auxiliary power supply is used to supply power to the first DC power supply, the second DC power supply, the first main control module, the second main control module, the first main power circuit, and the second main power circuit.

[0043] In the embodiment of the present invention, two sets of inverters are used to work in parallel, and the first main control module and the second main control module use a dual PID algorithm to feedback control the output line voltage of the two inverters. By setting two sets of inverters, disturbance tracking of power changes is achieved to ensure that the photovoltaic inverter works at the maximum power point, avoid divergence, and ensure the stable operation of the photovoltaic system under different operating conditions. This mechanism effectively reduces output fluctuations when the light changes rapidly.

[0044] See also Figure 2 The first main control module includes a first SVPWM generation module, a first PI adjustment module, a first sampling calculation module and a first GPIO module, the first sampling calculation module is connected to the output end of the first power circuit; the output end of the first sampling calculation module is connected to the first PI adjustment module, the output end of the first PI adjustment module is connected to the first SVPWM generation module, and the output end of the first SVPWM generation module is connected to the first main power circuit;

[0045] The second main control module includes a second SVPWM generation module, a second PI adjustment module, a second sampling calculation module and a second GPIO module. The second sampling calculation module is connected to the output end of the second power circuit; the output end of the second sampling calculation module is connected to the second PI adjustment module, the output end of the second PI adjustment module is connected to the second SVPWM generation module, and the output end of the second SVPWM generation module is connected to the second main power circuit.

[0046] In an embodiment of the present invention, the first main power circuit and the second main power circuit are powered by the first DC power supply and the second DC power supply respectively. After boosting, the first main control module and the second main control module respectively generate SVPWM waves to control the half-bridge driver EG3112 to achieve single-phase inversion. The SVPWM waves drive the single-phase inverter circuit through the driver chip to achieve DC to AC conversion, and power distribution is achieved by sampling the voltage and current and the PI algorithm. When the inverter is working, the SVPWM wave generated by STM32 is fed back to control the output line voltage using the PID algorithm according to the sampled voltage information. When the two inverters work in parallel, the SVPWM waves of the two inverters are fed back to control the output line voltage using the dual PID algorithm according to the sampled voltage and current information.

[0047] See also Figure 3 , the present invention realizes boundary condition monitoring by setting two groups of inverters to ensure that the tracking trajectory deviation of the photovoltaic inverter is minimized. While continuing to track, the normalized power change (ΔP / P) is measured and compared with the threshold ΔT. If ΔP / P<ΔT, it can be considered that the power change is not large enough, indicating that G changes slowly. In this case, the perturbation size is kept to a minimum, which is sufficient to cope with the slow change of g. Otherwise, when ΔP / P>ΔT, the perturbation is increased to ensure that the working point can cope with the gradient of g and avoid divergence.

[0048] Starting from the MPP (Maximum Power Point), a bound is introduced around the possible location of the MPP. Thus, the voltage will be forced to always stay within the bound and not diverge from the MPP region. But when the change in G eventually stops, the algorithm will stabilize at the MPP. Then around the MPP, it will detect oscillations and reduce the perturbation size to a minimum level.

[0049] The MPP is located near 0.8×Voc array (Voc array = Voc×Ns). Therefore, the initial search point of the MPPT (MPPT (Maximum Power Point Tracking)) is set to 0.65×Voc array. The reason for setting the initial value slightly away from the MPP is to record the gradient (r) of the PV curve (positive or negative), that is, ΔP and ΔV. The "value" is the signed multiplication of these two quantities and is normalized to unity. These values ​​will be used to determine whether the algorithm converges to the MPP and thus determine the change in the size of the disturbance. Oscillations are detected by recording five consecutive values ​​of φ. When the voltage increases or decreases, the consecutive 5 voltages are positive or negative, respectively. Therefore, the absolute value of the sum of all 5 values ​​is 5. After reaching the MPP, oscillations begin; the operating point will move twice in one direction and then in the opposite direction. Therefore, the absolute value of the sum of the five φ is always less than 5. Therefore, by recording five consecutive vibrations, the occurrence of oscillations can be accurately detected.

[0050] The boundary condition monitoring introduced in the present invention can analyze and adapt to environmental changes in real time, ensuring the stable operation of the photovoltaic system under different operating conditions. This mechanism effectively reduces output fluctuations when the light changes rapidly. It can intelligently handle rapid changes in external conditions, such as instantaneous changes in light, making the photovoltaic system more adaptable and better able to cope with complex environments in practical applications.

[0051] In the embodiment of the present invention, the first DC power supply and the second DC power supply, the first main control module and the second main control module, and the first main power circuit and the second main power circuit have the same structure.

[0052] In the embodiment of the present invention, the first main control module and the second main control module both use STM32F334 model MCU. The main control module needs to generate a high-frequency PWM signal to drive the MOS tube, and the PWM needs to obtain sufficiently high precision, involving loop calculation, and the MCU selection requirements are as follows: it has HRTIM (high-resolution timer), high main frequency, and because the national power time cycle is short, ST's STM32 series single-chip microcomputer is selected. Among them, the STM32F3 series is a Cortex-M4F core, 72MHz main frequency, with FPU, and some models have HRTIM. The present invention selects STM32F334 as the MCU of the single-phase inverter parallel operation system control board.

[0053] See also Figure 4 and Figure 5 The first sampling calculation module includes a current sampling amplifier circuit and a voltage sampling amplifier circuit, wherein the current sampling amplifier circuit adopts an INA199A2 amplifier, and the voltage sampling circuit adopts a GS8552 amplifier.

[0054] The sampling circuit uses an operational amplifier-based circuit to sample voltage and current, using INA199A2 as the current sampling amplifier circuit and GS8552 as the voltage sampling circuit, and uses the STM32 built-in ADC for sampling. It is cheap, has a wide range of options, and can sample line voltage and phase voltage through differential amplification.

[0055] In the embodiment of the present invention, the analog circuit power supply adopts 5V as the analog circuit power supply because the voltage curve of the operational amplifier is nonlinear when it is close to Vdd and Vss.

[0056] See also Figures 6 to 8 The auxiliary power supply includes three voltage circuits of 10V, 5V and 3.3V. Among them, the 10V power supply module adopts the XL7005A chip, the 5V power supply module adopts the MP2451 chip, and the 3.3V power supply module adopts the RT9193 chip.

[0057] In the embodiment of the present invention, the auxiliary circuit includes three voltage levels of 10V, 5V, and 3.3V; among them, the 10V auxiliary power supply is the first level of the power supply, adopts a high input voltage, and requires a current of 300mA, so a power supply module of model XL7005A is selected, wherein the parameters of XL7005A are Vmax: 80V, Imax: 0.4A, and switching frequency: 150kHz.

[0058] For the 5V auxiliary power supply, MP2451 is used for design. The switching frequency is high, the required capacitors and inductors are relatively small, the cost is low, and the size is small.

[0059] The 3.3V part is mainly used to power the MCU and peripheral circuits. The power required by this part is not high, so the smaller RT9193 is selected as the 3.3V auxiliary circuit chip.

[0060] See also Fig. 9 The first main power circuit adopts a single-phase inverter DC-AC circuit and a BOOST boost circuit; the output end of the BOOST boost circuit is connected to the single-phase inverter DC-AC circuit after being filtered by a low-pass filter.

[0061] Among them, the BOOST boost circuit adopts the N-channel MOS tube of BSC123N10LS, which has a low on-resistance of 7mΩ and a high withstand voltage of 100V.

[0062] For the BOOST boost circuit, calculate the Boost output capacitor and inductor values;

[0063]

[0064] According to the Boost inductor selection formula:

[0065]

[0066] Where: L is the inductance value, is the duty cycle of the MOS tube, r is the load resistance, is the switching frequency, and is the inductor current.

[0067] Since the buck-boost is bidirectionally symmetrical, the capacitor selection can be based on the buck selection, and the ripple size is 0.1%;

[0068] Designed with 4A output current, the inductor ripple current is taken as 20%~40% of the output current, and we can get: L∈[187.5, 375]μH. In summary, 220μH is selected as the boost inductor.

[0069] Take the output voltage ripple size as 5% of the output voltage, according to the output capacitor selection formula:

[0070]

[0071] Where: I0 is the output current, ΔU0 is the output ripple voltage, and D is the duty cycle;

[0072] Calculation shows that the output capacitance needs to be greater than 100μF, leaving a certain margin. We choose 220μF as the output filter capacitor.

[0073] We take the input voltage ripple size as 1% of the input voltage, according to the input capacitor selection formula:

[0074]

[0075] Among them; C is the capacitance value, is the MOS tube, D is the duty cycle wave size, f is the switching frequency, L is the inductance value, U is i is the output voltage.

[0076] It can be obtained that the input capacitance must be greater than 22.7μF, leaving a certain margin. We choose 220μF as the output filter capacitor.

[0077] In order to improve the efficiency of the inverter, the present invention improves the efficiency of the inverter by selecting the switching frequency. The high switching frequency can reduce the volume and weight of the converter and increase the output voltage THD. However, as the frequency increases, the loss of the switch tube will also increase. By setting a suitable drive circuit, it is possible to prevent ringing caused by improper design of the switch tube drive circuit or increase in switching loss due to a long rise time. The loss of the switch tube is proportional to the frequency. The higher the switching frequency, the higher the loss. Considering that the carrier frequency is much larger than the fundamental frequency, it is convenient for the subsequent design of the filter. Therefore, the switching frequency of the single-phase inverter DC-AC circuit is 25kHz;

[0078] The low-pass filter uses a second-order LC filter; its characteristic is low impedance, and choosing an inductor with a smaller inductance value can reduce the internal resistance. According to the cutoff frequency of the LC filter, since the inductor can be wound by itself to produce any inductance value, the cutoff frequency is usually selected to be above 10 times the fundamental frequency and below five times the carrier frequency. We choose a 220μH ferrite inductor and a 220μF high-frequency electrolytic capacitor. After calculation, its cutoff frequency is 723.43Hz, and the measured THD is 1.42%, which meets the design requirements.

[0079] See also Fig.10 The single-phase inverter DC-AC circuit is a EG3112 model driver module, with a maximum frequency of 500kHz; a low-end VCC voltage range of 2.8V-20V; an output current capacity of Io+ / -2A / 2.5A; a built-in dead zone control circuit; few peripheral devices; and a quiescent current of less than 1μA, which is very suitable for battery applications. Improve efficiency and reduce power loss.

[0080] In order to improve efficiency, we use DC-DC circuit to step down the voltage of the high-voltage difference step-down circuit, which can effectively improve efficiency. After the above optimization, our final inverter peak efficiency can reach 93%, which is significantly better than the design requirements.

[0081] In the embodiment of the present invention, the DC / DC conversion circuit adopts soft switching technology, such as zero voltage switching (ZVS), zero current switching (ZCS), etc.; the high-frequency conversion circuit and the coupled inductor are composed of a direct current-to-direct current conversion circuit (DC / DC) and a direct current-to-alternating current conversion circuit (DC / AC), wherein one DC / DC realizes maximum power point tracking and the other DC / AC is responsible for inversion; after internal logic processing and control, the controller outputs a driving signal to the DC / DC and DC / AC power switch tubes, which work with space vector pulse width modulation (SVPWM) high-frequency switching.

[0082] The present invention realizes dynamic change of disturbance size by setting two sets of inverters in parallel to reduce steady-state oscillation, thereby reducing the possibility of photovoltaic system disturbance and loss of tracking direction of maximum power point tracking (MPPT) based on observation (P&O). Dynamic boundary conditions are introduced in the maximum power point tracking algorithm to ensure that the algorithm does not deviate from its tracking trajectory.

[0083] The present invention can reduce steady-state oscillations, and by dynamically changing the disturbance size, reduce the steady-state oscillations of the photovoltaic system when tracking the maximum power point, improve the stability of the system, and ensure that the photovoltaic array operates at a higher efficiency near the maximum power point. Improve tracking accuracy, under different lighting conditions and load changes, by introducing dynamic boundary conditions, considering the dynamic boundaries under various working conditions, and improving the adaptability of the P&O algorithm in complex and changing environments, ensure that the photovoltaic system can effectively track the maximum power point under various conditions, ensure that the algorithm can remain within the effective tracking range, reduce the risk of losing the tracking direction, and enable the photovoltaic system to always be close to the actual maximum power point; improve the energy collection efficiency of the photovoltaic system under various working environments, reduce the energy loss caused by tracking failure, thereby improving the overall system performance and economic benefits.

[0084] The present invention can achieve high efficiency, high frequency, small size and low cost, and can be widely used in various bidirectional direct current-alternating current (DC / AC) inverters, such as solar photovoltaic power generation, off-grid household and industrial and commercial energy storage and other new energy systems, portable mobile energy storage power supplies, uninterruptible power supplies and electric vehicle motor drives.

[0085] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A photovoltaic grid-connected inverter based on disturbance tracking, characterized in that: include: A first DC power supply, a second DC power supply, a first main control module, a second main control module, a first main power circuit, a second main power circuit, an AC-AC conversion circuit, an isolation transformer and an auxiliary power supply; The first DC power supply is connected to the first main power circuit, and the first main power circuit is connected to the first main control module; The second DC power supply is connected to the second main power circuit, and the second main power circuit is connected to the second main control module; The output ends of the first main power circuit and the second main power circuit are connected to an AC-AC conversion circuit, and the output end of the AC-AC conversion circuit is connected to an isolation transformer; The auxiliary power supply is powered by the first DC power supply, the second DC power supply, the first main control module, the second main control module, the first main power circuit, and the second main power circuit.

2. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 1, characterized in that: The first main control module includes a first SVPWM generation module, a first PI adjustment module, a first sampling calculation module and a first GPIO module, the first sampling calculation module is connected to the output end of the first power circuit; the output end of the first sampling calculation module is connected to the first PI adjustment module, the output end of the first PI adjustment module is connected to the first SVPWM generation module, and the output end of the first SVPWM generation module is connected to the first main power circuit; The second main control module includes a second SVPWM generation module, a second PI regulation module, a second sampling calculation module and a second GPIO module. The second sampling calculation module is connected to the output end of the second power circuit; the output end of the second sampling calculation module is connected to the second PI regulation module, the output end of the second PI regulation module is connected to the second SVPWM generation module, and the output end of the second SVPWM generation module is connected to the second main power circuit.

3. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 2, characterized in that: The first main control module and the second main control module both use STM32F334 model MCU.

4. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 2, characterized in that: The first sampling calculation module includes a current sampling amplifier circuit and a voltage sampling amplifier circuit, wherein the current sampling amplifier circuit adopts an INA199A2 amplifier, and the voltage sampling circuit adopts a GS8552 amplifier.

5. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 1, characterized in that: The auxiliary power supply includes three voltage circuits of 10V, 5V and 3.3V, wherein the 10V power supply module adopts the XL7005A chip, the 5V power supply module adopts the MP2451 chip, and the 3.3V power supply module adopts the RT9193 chip.

6. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 1, characterized in that: The first main power circuit adopts a single-phase inverter DC-AC circuit and a BOOST boost circuit; the output end of the BOOST boost circuit is connected to the single-phase inverter DC-AC circuit after being filtered by a low-pass filter.

7. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 6, characterized in that: The BOOST boost circuit adopts an N-channel MOS tube of BSC123N10LS, and the low-pass filter selects a second-order LC filter.

8. The photovoltaic grid-connected inverter based on disturbance tracking according to claim 6, characterized in that: The single-phase inverter DC-AC circuit is a drive module of model EG3112.

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