High-efficiency high-power hybrid inverter for North America households

Abstract

The utility model discloses a high-efficiency high-power hybrid inverter for North America households, which comprises a main circuit, the main circuit comprises an MPPT (maximum power point tracking) circuit, an inverter circuit and a battery high-voltage pre-charging loop, the inverter circuit and the battery high-voltage pre-charging loop are connected in parallel with the output end of the MPPT circuit, and the MPPT circuit is connected with the inverter circuit and the battery high-voltage pre-charging loop through a DC BUS + and a DC BUS-. According to the utility model, through the energy control of the MPPT circuit and the inverter circuit, the DC bus voltage Vpn can be controlled, namely the voltage between the P point and the N point on the DC BUS, and the charging and discharging states of the battery can be realized. According to the utility model, the Vpn voltage is adopted to control the charging and discharging of the battery system, compared with the prior art, a bidirectional Buck / Boost circuit is removed, the conduction loss and the switching loss are reduced, the path of primary conversion is shorter than that of secondary conversion, the overall efficiency can be effectively improved by more than 3%, and the overall design cost of the system is reduced by 25%.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic power equipment, in particular to a high-efficiency high-power North American household hybrid inverter. Background Art

[0002] The traditional topology design of North American hybrid inverters can be divided into three parts: "PV-Boost (boost), battery bidirectional Buck / Boost, and inverter T-type three-level". Please refer to Figure 2 , among which, the "bidirectional Buck / Boost" circuit contains a boost energy storage inductor and a relatively large number of IGBT tubes, resulting in a larger volume and weight of the inverter.

[0003] If a "bidirectional Buck / Boost" circuit is built-in on the battery side of the inverter, the boost energy storage inductor of the circuit has losses during operation, and certain conduction losses and switching losses will be generated when the IGBT tubes are turned on and off. PV energy needs to pass through two-stage circuits of "PV-Boost (boost)" and battery "bidirectional Buck / Boost" to charge the battery, and the battery also needs to pass through two-stage circuit conversions of "battery bidirectional Buck / Boost" and "DC / AC (INV)" to discharge during battery discharge. The energy conversion path is long, resulting in a low charge-discharge conversion efficiency of the battery.

[0004] The current topology design of North American hybrid inverters can only be compatible with split-phase 120 / 240Vac voltage output or single-phase 240Vac output, and cannot directly achieve three-phase 208Vac or three-phase 400Vac voltage output. It can only be grouped into three-phase output by using three hybrid inverters of the same power, resulting in a high cost. The whole machine does not have a split-phase control function and cannot achieve two-phase or three-phase unbalance management.

[0005] Therefore, there are defects in the prior art and improvement is needed. Content of the Utility Model

[0006] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a high-efficiency high-power North American household hybrid inverter.

[0007] The technical solution of the present utility model is as follows: Provide a high-efficiency high-power North American household hybrid inverter, including: a main circuit, a DC arc detection circuit AFCI, an AC / DC surge protection circuit, an AC / DC EMI circuit, an LCL filter circuit, a leakage current monitoring circuit GFCI, a switching circuit, and a driving circuit. The main circuit is electrically connected to the AC / DC EMI circuit, the LCL filter circuit, and the driving circuit respectively. The input end of the main circuit is electrically connected to the DC arc detection circuit AFCI through the AC / DC EMI circuit. The LCL filter circuit is electrically connected to the leakage current monitoring circuit GFCI. The leakage current monitoring circuit GFCI is electrically connected to the switching circuit through the AC / DC EMI circuit. The switching circuit is connected to the power grid.

[0008] The main circuit includes an MPPT circuit, an inverter circuit, and a battery high-voltage pre-charge circuit. The inverter circuit and the battery high-voltage pre-charge circuit are connected in parallel to the output end of the MPPT circuit. The MPPT circuit is connected to the inverter circuit and the battery high-voltage pre-charge circuit through DC BUS+ and DC BUS-. An AC / DC EMI circuit is connected between the MPPT circuit, the battery high-voltage pre-charge circuit, and the driving circuit. The battery high-voltage pre-charge circuit is electrically connected to the driving circuit.

[0009] Further, the inverter circuit includes: switching tubes T5, T6, T7, T8, T9, T10, T11, and T12. The collectors of switching tubes T5, T7, T9, and T11 are connected in parallel to DC BUS+ of the MPPT circuit. The collectors of switching tubes T6, T8, T10, and T12 are connected in parallel to DC BUS- of the MPPT circuit. The emitters of switching tubes T5 and T6 are connected in parallel to the LCL filter circuit. The emitters of switching tubes T7 and T8 are connected in parallel to the LCL filter circuit. The emitters of switching tubes T9 and T10 are connected in parallel to the LCL filter circuit. The emitters of switching tubes T11 and T12 are connected in parallel to the LCL filter circuit. Switching tubes T5 and T6, T7 and T8, T9 and T10, and T11 and T12 respectively form bridge arms.

[0010] Further, the LCL filter circuit includes: inductor L5, inductor L6, inductor L7, inductor L8, inductor L9, inductor L10, inductor L11, inductor L12, capacitor C11, capacitor C12, capacitor C13, and capacitor C14. One end of the inductor L5 is electrically connected to the emitter of the switching transistor T5 and the emitter of the switching transistor T6. One end of the inductor L6 is electrically connected to the emitter of the switching transistor T7 and the emitter of the switching transistor T8. One end of the inductor L7 is electrically connected to the emitter of the switching transistor T9 and the emitter of the switching transistor T10. One end of the inductor L8 is electrically connected to the emitter of the switching transistor T11 and the emitter of the switching transistor T12. The other end of the inductor L5 is electrically connected to one end of the inductor L9 and one end of the capacitor C11. The other end of the inductor L6 is electrically connected to one end of the inductor L10 and one end of the capacitor C12. The other end of the inductor L7 is electrically connected to one end of the inductor L11 and one end of the capacitor C13. The other end of the inductor L8 is electrically connected to one end of the inductor L12 and one end of the capacitor C14. The other ends of the capacitor C11, the capacitor C12, the capacitor C13, and the capacitor C14 are connected in parallel. The other ends of the inductor L9, the inductor L10, the inductor L11, and the inductor L12 are respectively connected to the leakage current monitoring circuit GFCI.

[0011] Further, the battery high-voltage pre-charge circuit includes: DC contactor KM, fuse FU, and pre-charge resistor R. One end of the fuse FU is connected to one end of the pre-charge resistor R. The other end of the pre-charge resistor R is connected to one end of the DC contactor KM and is connected to the AC-DC EMI circuit. The other end of the fuse FU is connected to the other end of the DC contactor KM and is connected to the BAT+ of the drive circuit.

[0012] Further, the drive circuit uses a battery system, and the battery system uses a single battery cluster configured with 0.5C.

[0013] Further, the switching circuit includes: AC relay RY1#, AC relay RY2#, AC relay RY3#, and AC relay RY4#. One end of the AC relay RY1# is electrically connected to the leakage current monitoring circuit GFCI through the AC-DC EMI circuit. One ends of the AC relay RY2#, the AC relay RY3#, and the AC relay RY4# are connected in parallel and connected to the other end of the AC relay RY1#. The other ends of the AC relay RY2#, the AC relay RY3#, and the AC relay RY4# are respectively connected to the power grid.

[0014] Adopting the above solution, the utility model has the following technical features and advantages:

[0015] (1) The installation position of the inductance L3 bridge arm can be reserved, and the whole machine is effectively compatible with North American split-phase power grids and three-phase power grids in North America, Europe, China, South Africa, etc.;

[0016] (2) The inverter topology has a battery-less bidirectional DC / DC controller, which greatly reduces the number of switching devices, reduces the volume of the whole machine and the system cost, and improves the system efficiency;

[0017] (3) The battery side of the inverter is a high-voltage battery. The higher the battery voltage, the smaller the battery current, the smaller the capacity of the selected electronic components, and the lower the hardware design cost of the whole machine; and because there is no bidirectional Buck / Boost circuit on the battery side, compared with the hybrid inverter products with built-in battery bidirectional Buck / Boost circuits in the same power range, the volume of the whole machine is effectively reduced by more than 20%, achieving cost reduction and efficiency improvement;

[0018] (4) The battery system is configured according to 0.5C to meet the minimum working voltage requirements of the battery, and is designed as a single battery cluster. Configuring a higher battery voltage is beneficial to solving the circulating current problem of multi-battery cluster parallel connection;

[0019] (5) It has a wide battery input voltage range (370Vdc - 800Vdc) and a photovoltaic input voltage range (180Vdc - 1000Vdc). The higher the battery working voltage, the higher the conversion efficiency. At the same time, due to the removal of the bidirectional Buck / Boost circuit, the conduction loss and switching loss are reduced, and the first-level conversion path is shorter than the second-level conversion path, so the efficiency of the whole machine can be effectively increased by more than 3%;

[0020] (6) The inverter circuit adopts a two-level three-phase four-arm topology structure. Each arm of each phase, including the neutral point, can be independently controlled, with the ability of split-phase or three-phase independent output control, and supports single-phase charging and single-phase discharging at the same time; by adjusting the active / reactive power of the split-phase / three-phase output, the function of two-phase or three-phase unbalance control can be realized, and when in a two-phase or three-phase balanced state, the zero-sequence current on the neutral line N is 0;

[0021] (7) The high-voltage battery is directly connected to the DC BUS. By controlling the energy of the MPPT circuit and the inverter circuit, the level of the DC bus voltage Vpn can be controlled to realize the charging and discharging of the battery;

[0022] (8) The filter circuit adopts an LCL filter circuit, which effectively filters out high-frequency harmonics in the inverter output current, controls THDi < 3%, and uses a smaller inductance value to effectively improve the inverter efficiency and effectively suppress resonance. Description of the Drawings

[0023] Figure 1 It is a schematic diagram of the connection of the circuit modules of the present utility model.

[0024] Figure 2 Schematic diagram of the connection of a circuit module in the prior art. Specific implementation manner

[0025] The present utility model will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] Please refer to Figure 1 , the present utility model provides a high-efficiency high-power North American household hybrid inverter, including: a main circuit, a DC arc-fault detection circuit AFCI, an AC / DC surge protection circuit, an AC / DC EMI circuit, an LCL filter circuit, a leakage current monitoring circuit GFCI, a switching circuit, and a driving circuit. The main circuit is electrically connected to the AC / DC EMI circuit, the LCL filter circuit, and the driving circuit respectively. The input end of the main circuit is electrically connected to the DC arc-fault detection circuit AFCI through the AC / DC EMI circuit. The LCL filter circuit is electrically connected to the leakage current monitoring circuit GFCI. The leakage current monitoring circuit GFCI is electrically connected to the switching circuit through the AC / DC EMI circuit. The switching circuit is connected to the power grid.

[0027] The main circuit includes an MPPT circuit (PV-boost), an inverter circuit (INV), and a battery high-voltage pre-charge circuit. The inverter circuit and the battery high-voltage pre-charge circuit are connected in parallel to the output end of the MPPT circuit. The MPPT circuit is connected to the inverter circuit and the battery high-voltage pre-charge circuit through DC BUS+ and DC BUS-. An AC / DC EMI circuit is connected between the MPPT circuit and the battery high-voltage pre-charge circuit and the driving circuit. The battery high-voltage pre-charge circuit is electrically connected to the driving circuit.

[0028] The inverter circuit includes: switching transistors T5, T6, T7, T8, T9, T10, T11, and T12. The collectors of switching transistors T5, T7, T9, and T11 are connected in parallel to the DC BUS+ of the MPPT circuit. The collectors of switching transistors T6, T8, T10, and T12 are connected in parallel to the DC BUS- of the MPPT circuit. The emitters of switching transistors T5 and T6 are connected in parallel to the LCL filter circuit. The emitters of switching transistors T7 and T8 are connected in parallel to the LCL filter circuit. The emitters of switching transistors T9 and T10 are connected in parallel to the LCL filter circuit. The emitters of switching transistors T11 and T12 are connected in parallel to the LCL filter circuit. Switching transistors T5 and T6, T7 and T8, T9 and T10, and T11 and T12 respectively form bridge arms. The inverter circuit adopts a two-level three-phase four-bridge-arm topology structure, including a neutral point. Each phase bridge arm (switching transistors T5 and T6 form the bridge arm of inductor L1 in the MPPT circuit, switching transistors T7 and T8 form the bridge arm of inductor L2 in the MPPT circuit, switching transistors T9 and T10 form the bridge arm of inductor L3 in the MPPT circuit, and switching transistors T11 and T12 form the bridge arm of inductor L4 in the MPPT circuit) can be independently controlled, with the ability of split-phase or three-phase independent output control, and supports the working condition of single-phase charging and single-phase discharging at the same time. Meanwhile, by adjusting the active / reactive power of the split-phase / three-phase output, the function of two-phase or three-phase unbalance governance can be realized, and the zero-sequence current on the neutral line N is 0 in the two-phase or three-phase balanced state.

[0029] Among them, switching transistors T9 and T10 form the bridge arm of inductor L3 in the MPPT circuit, reserving a bridge arm position for inductor L3, effectively compatible with North American split-phase power grids and three-phase power grids in North America, Europe, China, South Africa, etc.

[0030] The LCL filter circuit includes: inductor L5, inductor L6, inductor L7, inductor L8, inductor L9, inductor L10, inductor L11, inductor L12, capacitor C11, capacitor C12, capacitor C13, and capacitor C14. One end of the inductor L5 is electrically connected to the emitter of the switching transistor T5 and the emitter of the switching transistor T6. One end of the inductor L6 is electrically connected to the emitter of the switching transistor T7 and the emitter of the switching transistor T8. One end of the inductor L7 is electrically connected to the emitter of the switching transistor T9 and the emitter of the switching transistor T10. One end of the inductor L8 is electrically connected to the emitter of the switching transistor T11 and the emitter of the switching transistor T12. The other end of the inductor L5 is electrically connected to one end of the inductor L9 and one end of the capacitor C11. The other end of the inductor L6 is electrically connected to one end of the inductor L10 and one end of the capacitor C12. The other end of the inductor L7 is electrically connected to one end of the inductor L11 and one end of the capacitor C13. The other end of the inductor L8 is electrically connected to one end of the inductor L12 and one end of the capacitor C14. The other ends of the capacitor C11, the capacitor C12, the capacitor C13, and the capacitor C14 are connected in parallel. The other ends of the inductor L9, the inductor L10, the inductor L11, and the inductor L12 are respectively connected to the leakage current monitoring circuit GFCI. The filter circuit adopts the LCL filter circuit, which can effectively filter out the high-frequency harmonics in the inverter output current, control THDi < 3%, and effectively improve the inverter efficiency with a smaller inductance value and effectively suppress resonance.

[0031] The battery high-voltage pre-charge circuit includes: DC contactor KM, fuse FU, and pre-charge resistor R. One end of the fuse FU is connected to one end of the pre-charge resistor R. The other end of the pre-charge resistor R is connected to one end of the DC contactor KM and is connected to the AC-DC EMI circuit. The other end of the fuse FU is connected to the other end of the DC contactor KM and is connected to BAT+ of the drive circuit.

[0032] The drive circuit adopts a battery system, and the battery system adopts a single battery cluster configured with 0.5C. Considering the relationship between the effective value and the maximum value of the sinusoidal alternating current and the margin of the bus voltage, the minimum operating voltage of the battery is configured as 370Vdc when the split-phase 120 / 240Vac is output, and the minimum operating voltage of the battery is configured as 600Vdc when the three-phase 400Vac is output. The battery system is configured with 0.5C, that is, it corresponds to the series design of 12 51.2V / 100Ah and the series design of 14 51.2V / 100Ah respectively, meeting the requirements of the minimum operating voltage of the battery, and being a single battery cluster design. Configuring a higher battery voltage is beneficial to solving the circulating current problem of multiple battery clusters in parallel.

[0033] The switching circuit includes: AC relay RY1, AC relay RY2, AC relay RY3, and AC relay RY4. One end of the AC relay RY1 is electrically connected to the leakage current monitoring circuit GFCI through an AC-DC EMI circuit. One ends of the AC relay RY2, the AC relay RY3, and the AC relay RY4 are connected in parallel to the other end of the AC relay RY1. The other ends of the AC relay RY2, the AC relay RY3, and the AC relay RY4 are respectively connected to the power grid. When the hybrid inverter is working, turn on the PV Switch of the hybrid inverter and press the ON / OFF button. After the DC bus voltage is established by the photovoltaic or battery energy, the AC relay RY1 on the inverter module side closes. When the phase-locked device on the GRID side detects that the grid voltage, frequency, and phase meet the grid connection requirements, the AC relay RY2 on the grid side synchronously closes, and the inverter operates in parallel with the grid. When the inverter operates off-grid, the AC relay RY2 is directly disconnected, and at the same time, it switches to the V / F operation mode.

[0034] In some embodiments, the Load1 port of the hybrid inverter is connected to the most critical load, and the Load2 port is connected to the secondary important load. When the hybrid inverter operates in the off-grid mode, this solution can achieve intelligent switching of the secondary important load according to the current SOC of the battery, giving priority to ensuring the power supply of the most important load, that is, by setting the level of the battery SOC, the on / off of the AC relay RY3 at the Load2 port is realized, ensuring intelligent switching between different loads.

[0035] The high-efficiency high-power North American household hybrid inverter provided by the present invention has a power of 30kW - 50kW. Its inverter circuit is designed with two-level three-phase four-arm, which can achieve the function of separate phase control and is compatible with the grid requirements of regions such as North America, China, Europe, South Africa, and the Middle East, improving versatility.

[0036] Between the MPPT circuit, the battery high-voltage pre-charge circuit, and the drive circuit, that is, on the battery side of the hybrid inverter, the conventional bidirectional Buck / Boost circuit is omitted, and the Vpn voltage (the P point and N point on the DC BUS) is used to control the charge and discharge of the battery system. The MPPT circuit PV-Boost is a unidirectional control circuit, and PV energy can only be input from the low-voltage side of the Boost circuit to directly charge the battery of the battery system (the current direction is from PV to Batt) or supply power to the AC load through the inverter circuit INV again (the current direction is from PV to the grid load Load). The inverter circuit INV is a bidirectional control circuit that can control the charging and discharging processes of the battery, realizing the conversion of AC and DC energy. By controlling the energy of the MPPT circuit (PV-Boost) and the inverter circuit, the DC bus voltage Vpn, that is, the voltage between the P point and N point on the DC BUS, can be controlled to realize the charge and discharge state of the battery. The current SOC of the battery determines the terminal voltage of the battery. When the DC bus voltage Vpn > the terminal voltage Vce of the current DC side (that is, the voltage between the C point and E point on the battery input side), the energy on the DC BUS can charge the battery; when the DC bus voltage Vpn < the terminal voltage Vce of the battery side, the battery energy will discharge to the DC BUS; when the DC bus voltage Vpn = the terminal voltage Vce of the battery DC side, the DSP software stops sending drive pulses to the T21 and T22 switching tubes, thus disconnecting the battery connection, and at this time the battery does not charge or discharge.

[0037] The high-efficiency high-power North American household hybrid inverter provided by the present utility model has a wide battery input voltage range (370Vdc - 800Vdc) and a photovoltaic input voltage range (180Vdc - 1000Vdc). The higher the battery operating voltage, the higher its conversion efficiency. By using the Vpn voltage to control the charge and discharge of the battery system, the present utility model removes the bidirectional Buck / Boost circuit compared with the prior art, reduces the conduction loss and switching loss, makes the first-level conversion path shorter than the second-level conversion path, and the overall efficiency of the whole machine can be effectively increased by more than 3%.

[0038] Since there is no bidirectional DC / DC controller configured on the battery side, the situation where the battery is out of control will occur. Therefore, in order to solve the problem that after the battery is fully charged, due to communication delay, if there is excess power in the photovoltaic, it may cause overcharging of the battery. In some embodiments, a Hall sensor is configured to detect the PV current and the battery current respectively, and then the detection results are sent to the control system. The DSP software combines deviation calibration to solve the problem of small current charging after the battery is prohibited from charging, and avoid overcharging that may cause damage to the battery.

[0039] In summary, the present utility model controls the circuit unidirectionally through the MPPT circuit. The PV energy is input from the low-voltage side of the Boost circuit to directly charge the storage battery of the battery system, or is supplied to the AC load after passing through the inverter circuit again. The inverter circuit controls the charging and discharging processes of the battery, realizing the conversion of AC and DC energies. By controlling the energies of the MPPT circuit and the inverter circuit, the DC bus voltage Vpn can be controlled, that is, the voltage between point P and point N on the DC BUS, to realize the charging and discharging states of the battery. The present utility model controls the charging and discharging of the battery system by using the Vpn voltage. Compared with the prior art, the bidirectional Buck / Boost circuit is removed, reducing the conduction loss and switching loss. The single-stage conversion has a shorter path than the two-stage conversion, and the overall efficiency of the machine can be effectively increased by more than 3%, and the overall design cost of the system is reduced by 25%.

[0040] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An efficient high-power North American household hybrid inverter, characterized in that, Including: A main circuit, a DC arcing detection circuit AFCI, an AC / DC surge protection circuit, an AC / DC EMI circuit, an LCL filter circuit, a leakage current monitoring circuit GFCI, a switching circuit, and a drive circuit. The main circuit is electrically connected to the AC / DC EMI circuit, the LCL filter circuit, and the drive circuit respectively. The input end of the main circuit is electrically connected to the DC arcing detection circuit AFCI through the AC / DC EMI circuit. The LCL filter circuit is electrically connected to the leakage current monitoring circuit GFCI. The leakage current monitoring circuit GFCI is electrically connected to the switching circuit through the AC / DC EMI circuit. The switching circuit is connected to the power grid. The main circuit includes an MPPT circuit, an inverter circuit, and a battery high-voltage pre-charge loop. The inverter circuit and the battery high-voltage pre-charge loop are connected in parallel to the output end of the MPPT circuit. The MPPT circuit is connected to the inverter circuit and the battery high-voltage pre-charge loop through DC BUS+ and DC BUS-. An AC / DC EMI circuit is connected between the MPPT circuit, the battery high-voltage pre-charge loop, and the drive circuit. The battery high-voltage pre-charge loop is electrically connected to the drive circuit.

2. The high-efficiency high-power North American household hybrid inverter according to claim 1, characterized in that, The inverter circuit includes: switching transistors T5, T6, T7, T8, T9, T10, T11, and T12. The collectors of switching transistor T5, T7, T9, and T11 are connected in parallel and connected to DC BUS+ of the MPPT circuit. The collectors of switching transistor T6, T8, T10, and T12 are connected in parallel and connected to DC BUS- of the MPPT circuit. The emitters of switching transistor T5 and T6 are connected in parallel and connected to the LCL filter circuit. The emitters of switching transistor T7 and T8 are connected in parallel and connected to the LCL filter circuit. The emitters of switching transistor T9 and T10 are connected in parallel and connected to the LCL filter circuit. The emitters of switching transistor T11 and T12 are connected in parallel and connected to the LCL filter circuit. Switching transistor T5 and T6, T7 and T8, T9 and T10, and T11 and T12 respectively form bridge arms.

3. The high-efficiency high-power North American household hybrid inverter according to claim 2, wherein, The LCL filter circuit includes: inductor L5, inductor L6, inductor L7, inductor L8, inductor L9, inductor L10, inductor L11, inductor L12, capacitor C11, capacitor C12, capacitor C13, and capacitor C14. One end of the inductor L5 is electrically connected to the emitter of the switching transistor T5 and the emitter of the switching transistor T6. One end of the inductor L6 is electrically connected to the emitter of the switching transistor T7 and the emitter of the switching transistor T8. One end of the inductor L7 is electrically connected to the emitter of the switching transistor T9 and the emitter of the switching transistor T10. One end of the inductor L8 is electrically connected to the emitter of the switching transistor T11 and the emitter of the switching transistor T12. The other end of the inductor L5 is electrically connected to one end of the inductor L9 and one end of the capacitor C11. The other end of the inductor L6 is electrically connected to one end of the inductor L10 and one end of the capacitor C12. The other end of the inductor L7 is electrically connected to one end of the inductor L11 and one end of the capacitor C13. The other end of the inductor L8 is electrically connected to one end of the inductor L12 and one end of the capacitor C14. The other ends of the capacitor C11, the capacitor C12, the capacitor C13, and the capacitor C14 are connected in parallel. The other ends of the inductor L9, the inductor L10, the inductor L11, and the inductor L12 are respectively connected to the leakage current monitoring circuit GFCI.

4. The high-efficiency high-power North American household hybrid inverter according to claim 1, characterized in that The battery high-voltage pre-charging circuit includes: DC contactor KM, fuse FU, and pre-charge resistor R. One end of the fuse FU is connected to one end of the pre-charge resistor R. The other end of the pre-charge resistor R is connected to one end of the DC contactor KM and is connected to the AC-DC EMI circuit. The other end of the fuse FU is connected to the other end of the DC contactor KM and is connected to BAT+ of the drive circuit.

5. The high-efficiency high-power North American household hybrid inverter according to claim 1, characterized in that, The drive circuit uses a battery system, and the battery system uses a single battery cluster configured with 0.5C.

6. The high-efficiency high-power North American household hybrid inverter according to claim 1, characterized in that, The switching circuit includes: AC relay RY1#, AC relay RY2#, AC relay RY3#, and AC relay RY4#. One end of the AC relay RY1# is electrically connected to the leakage current monitoring circuit GFCI through the AC-DC EMI circuit. One ends of the AC relay RY2#, the AC relay RY3#, and the AC relay RY4# are connected in parallel and connected to the other end of the AC relay RY1#. The other ends of the AC relay RY2#, the AC relay RY3#, and the AC relay RY4# are respectively connected to the power grid.

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