Hybrid multi-level inverter

Abstract

The invention relates to the technical field of inverters, in particular to a hybrid multi-level inverter which comprises a shell, a cooling fan and a filter block, a circuit system is arranged in the shell, an air inlet and two air outlets are formed in the side wall of the shell, and the air inlet is located between the two air outlets; the filter block capable of absorbing water is arranged between the cooling fan and the shell, so that dryness of gas entering the shell is guaranteed, meanwhile, the filter block is slidably connected into the outer frame rotationally connected with the shell, the switching assembly is arranged to drive the outer frame to rotate, and when an original air inlet area of the filter block absorbs water and reaches a saturated state, the air inlet area of the filter block is switched to the air inlet area. The switching assembly drives the outer frame to rotate, and the filter block slides in the inclined outer frame, so that the filter block is switched between a water absorption saturation area and an unsaturated area, the drying effect of the filter block on gas entering the shell is ensured, the gas in the shell is ensured to be dry, and the service life of the hybrid multi-level inverter is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of inverters, and in particular to a hybrid multi-level inverter. Background Art

[0002] The hybrid multilevel inverter combines the advantages of traditional multilevel inverters and other power conversion technologies. Its main feature is that it can convert at multiple voltage levels, thereby reducing harmonic distortion, reducing power loss and improving the overall conversion efficiency of the system. It is often used in photovoltaic systems and high-voltage direct current transmission and other fields.

[0003] Although the hybrid multilevel inverter can reduce the voltage stress of the internal switching devices, during the operation of the hybrid multilevel inverter, the operating frequency of the switching devices of the hybrid multilevel inverter is higher than that of the switching devices of the conventional inverter, which easily leads to an increase in the heat generated by the switching devices. Therefore, effective cooling and heat dissipation measures are required; the existing heat dissipation is mainly based on exhaust heat dissipation. By setting a heat dissipation fan in the hybrid multilevel inverter, the gas flow in the hybrid multilevel inverter is forced, thereby dissipating the heat of the internal circuit system of the hybrid multilevel inverter. By setting the exhaust power of the heat dissipation fan, the heat dissipation demand of the hybrid multilevel inverter can be basically met.

[0004] However, in the household photovoltaic panel system in the coastal area, due to the high air humidity in the coastal area, especially in the coastal area of ​​the southern region, the moisture entering the hybrid multilevel inverter through the heat dissipation system is easy to cause corrosion and short circuit to the circuit system of the hybrid multilevel inverter, and the air in the coastal area also contains corrosive salt components, which will aggravate the corrosion of the circuit system of the hybrid multilevel inverter; for this reason, some hybrid multilevel inverters are equipped with a heat dissipation system with a drying sheet for the coastal area, and its main structure is to set a drying sheet at the air inlet to dry the gas entering the hybrid multilevel inverter; however, after a certain period of use, the water content in the drying sheet reaches the saturation amount, and the drying effect of the drying sheet will drop sharply, so that the moist salty gas will still enter the hybrid multilevel inverter, thereby reducing the hybrid multilevel inverter and increasing the maintenance cost of the hybrid multilevel inverter. Summary of the invention

[0005] The object of the present invention is to provide a hybrid multilevel inverter to solve the problem that when the hybrid multilevel inverter is used in a humid environment with saline gas, the humid saline gas enters the hybrid multilevel inverter through the heat dissipation channel, which easily causes corrosion of the internal circuit board of the multilevel inverter, thereby reducing the service life of the multilevel inverter and increasing the maintenance cost of the hybrid multilevel inverter.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A hybrid multilevel inverter comprises a shell, a cooling fan and a filter block, wherein a circuit system is arranged in the shell; specifically, an air inlet and two air outlets are arranged on a side wall of the shell, the air inlet is located between the two air outlets, the cooling fan is connected to the inner side wall of the shell, and the side projection of the cooling fan is completely located in the air inlet, an outer frame is arranged between the cooling fan and the shell, the outer frame is rotatably connected to the shell, a mounting hole is arranged in the outer frame, the filter block is slidably mounted in the mounting hole, the lateral projections of the air inlet and the air outlet are both located in the mounting hole, the lateral projection of the filter block covers the air inlet and one air outlet, the wind direction of the cooling fan is from the air inlet to the shell, a switching component for driving the outer frame to rotate is arranged on the inner side wall of the shell, and the switching component is connected to the air duct of the cooling fan.

[0008] By setting the wind direction of the cooling fan to blow from the air inlet to the shell, when the cooling fan is working, the side of the cooling fan close to the filter block is in a negative pressure state, and the gas outside the shell flows to the cooling fan under the action of the negative pressure. The gas needs to pass through the filter block during the flow process. The filter block can be provided with a water-absorbing material, such as a highly absorbent resin, bamboo fiber or activated carbon material. The gas dried by the filter block reaches the air duct of the cooling fan, and then blows to the inside of the shell through the air duct of the cooling fan. At this time, the shell is in a positive pressure state, and the positive pressure gas is discharged to the outside of the shell through the gap between the air outlet and the shell. At the same time, the positive pressure gas discharges the heat generated by the circuit system to the outside of the shell; the dry state of the gas in the shell is ensured, and the humid gas in the humid environment is prevented from corroding the circuit system in the hybrid multilevel inverter, thereby ensuring the service life of the hybrid multilevel inverter.

[0009] Furthermore, when the hybrid multilevel inverter operates in a humid environment for a long time, when the water absorption of the filter block reaches the saturation value, the drying effect of the filter block on the gas will drop sharply, resulting in wet gas entering the shell. Therefore, by setting an outer frame and a switching component rotatably connected to the shell, when the original air inlet area of the filter block absorbs water to saturation, the switching component drives the outer frame to rotate. Since the filter block is slidably connected to the outer frame, after the outer frame rotates to a set angle, the filter block slides in the mounting hole under the action of gravity. At this time, the original air inlet area of the filter block slides to the air outlet, and the positive pressure gas in the shell is discharged out of the shell through the original air inlet area of the filter block. The heat in the positive pressure gas evaporates the water in the filter block, and at the same time, the flowing positive pressure gas takes the water in the filter block out. The original air outlet area of the filter block slides to the air inlet and dries the gas entering the shell. When the water absorption of the original air outlet area of the filter block reaches saturation, the switching component drives the outer frame to rotate again, sliding the original air outlet area of the filter block to the air outlet and the original air inlet area of the filter block to the air inlet hole. Thus, the gas in the shell is further ensured to be dry, and the service life of the hybrid multilevel inverter is guaranteed.

[0010] Preferably, a mounting seat is provided on the inner side wall of the shell. The mounting seat has a "C" - shaped structure with a mounting groove on one side. The mounting groove faces the air inlet. The cooling fan is installed on the side wall of the mounting seat. Ventilation holes concentric with the air duct of the cooling fan are provided on the side wall of the mounting seat. The side projection of the ventilation holes is completely located within the air inlet. An arc - shaped protrusion is provided in the middle of the bottom wall of the mounting groove, and the center line of the arc - shaped protrusion is parallel to the center line of the cooling fan. The outer frame and the filter block are arranged in the mounting groove. An arc - shaped groove is provided in the middle of the lower end surface of the outer frame. The arc - shaped groove is rotatably connected to the arc - shaped protrusion, and a movable gap is provided between the lower end surface of the outer frame and the bottom wall of the mounting groove.

[0011] Preferably, a ring - shaped protrusion is provided in the mounting groove. The ring - shaped protrusion and the ventilation holes are coaxial. A sealing ring is coaxially arranged on the end surface of the ring - shaped protrusion close to the filter block. The sealing ring is slidably connected to the filter block.

[0012] Through the setting of the mounting seat, it is convenient for the assembly of the cooling fan, the filter block and the shell. At the same time, the mounting seat limits the maximum rotation angle of the outer frame, avoiding the situation that the outer frame rotates too large an angle during the switching process, resulting in the filter block deviating from the lateral projection area of the air outlet, and then reducing the drying effect of the positive pressure gas on the filter block. When the switching component drives the outer frame to rotate, after the outer frame rotates until its lower surface contacts the bottom wall of the mounting groove, the outer frame cannot continue to rotate, thus ensuring that after the filter block stops sliding in the mounting hole, the front or rear air outlet is completely located within the lateral projection of the filter block, ensuring the drying effect of the positive pressure gas on the filter block.

[0013] Furthermore, if the filter block is slidably connected to the mounting seat, the fitting area between the filter block and the mounting seat will be too large, which may easily cause excessive friction between the filter block and the mounting seat, resulting in too slow a sliding speed of the filter block or obstructed sliding; for this reason, an annular protrusion and a sealing ring are provided in the mounting groove, and there is line contact between the sealing ring and the filter block, thereby reducing the resistance of the filter block during sliding, thereby improving the smoothness and stability of the filter block when sliding in the mounting hole; not only that, the inner side of the annular protrusion is in a negative pressure state, and the filter block is acted upon by negative pressure suction, and the side wall of the filter block remains in contact with the sealing ring, so that the negative pressure suction of the cooling fan completely acts on the filter block, thereby ensuring the air intake effect, thereby ensuring the heat dissipation effect of the hybrid multi-level inverter.

[0014] Preferably, an inner frame is arranged between the outer frame and the filter block, the filter block is interference installed in the inner frame, and the upper and lower inner side walls of the outer frame are provided with slide grooves, the slide grooves are rectangular, and the upper and lower outer side walls of the inner frame are respectively provided with a plurality of ball head support rods, one end of the ball head support rod is fixedly connected to the inner frame, and the other end is slidably connected to the inner wall of the slide groove, the end of the ball head support rod slidably connected to the slide groove is in the shape of a ball head, and the diameter of the ball head is equal to the width of the slide groove.

[0015] The direct sliding connection between the filter block and the inner wall of the mounting hole will cause the fitting area between the filter block and the outer frame to be too large, which may easily cause the friction between the filter block and the outer frame to be too large, resulting in the sliding speed of the filter block to be too slow or the sliding being blocked; for this reason, by arranging slide grooves on the upper and lower inner walls of the mounting hole, and by arranging a ball head support rod, the ball head support rod is in point contact with the inner wall of the slide groove, thereby reducing the resistance encountered by the filter block during the sliding process, thereby improving the smoothness and stability of the filter block when sliding in the mounting hole, and by improving the switching speed of the filter block between the water absorption saturated area and the unsaturated area, the drying effect of the filter block on the gas entering the shell is guaranteed, thereby ensuring the drying of the gas in the shell and ensuring the service life of the hybrid multi-level inverter.

[0016] Optionally, the switching component can adopt any one of a servo, an electric push rod, and a stepper motor, wherein the servo and the stepper motor can be directly connected to the outer frame to drive the outer frame to rotate, and the electric push rod needs to be connected to the front and rear side walls of the outer frame to drive the outer frame to rotate through the lever principle. The above three schemes can all realize the rotation drive of the outer frame, but the above three schemes all need to test the water content of the filter block or the negative pressure value on the inner side of the annular protrusion, so as to drive the outer frame to rotate after the water content in the filter block reaches the set value; it is easy to be affected by the failure of the detection element and produce misjudgment.

[0017] Preferably, the switching assembly includes a slide rail, a slider, two air valves and two on-off switches, the slide rail is arranged in the mounting groove, a circular slideway is provided in the slide rail, and the trajectory of the slideway is an arc, the slider is slidably connected in the slideway, and a limiting hole is symmetrically provided on an end surface of the slide rail close to the filter block, the limiting hole is connected to the slideway, two levers are symmetrically provided on the slider, both of the two levers extend outside the limiting hole, and both of the two levers are tangent to the upper end surface of the outer frame, the two air valves are respectively provided at both ends of the slide rail, and both of the two air valves are connected to the slideway, two communicating holes are symmetrically provided on the inner side wall of the annular protrusion, the two air valves are respectively connected to the two communicating holes, the two channel switches are symmetrically provided on the left and right sides of the upper end surface of the mounting seat, and the two on-off switches are electrically connected to the two air valves.

[0018] By arranging a slide rail, a slider and a lever in the mounting groove, when the water content of the filter block increases, the negative pressure value in the annular protrusion increases. Since the slideway is connected to the inner side of the annular protrusion, the slideway is in a negative pressure state, and the slider is under the action of the negative pressure; since both sides of the slideway are connected to the inner side of the annular protrusion, both sides of the slider are subjected to the negative pressure of the same magnitude. Therefore, through the arrangement of the air valve and the on-off switch, when the outer frame is in an inclined state, the on-off switch on the front or rear side is triggered, the air valve on the side of the triggered on-off switch is converted to a through state, and the air valve on the other side is closed, thereby avoiding the negative pressure on both sides of the slider; thus, the slider is subjected to the negative pressure on the side where the air valve is in the through state, and the slider moves along the track of the slideway, and the lever and The outer frames slide relative to each other and press down the outer frame on the side where the air valve is in the through state until the outer frame tilts to the lower end face of the outer frame in contact with the mounting seat. At this time, the on-off switch on the other side is triggered, and the air valve in the original through state is converted to the closed state, and the air valve in the original closed state is converted to the through state. At the same time, the inner frame and the outer frame slide relative to each other, and the original air inlet area of ​​the filter block slides to the air outlet, and the original air outlet area of ​​the filter block slides to the air inlet; thereby completing the switching of the filter block between the air inlet and the air outlet, thereby ensuring the dryness of the gas in the shell and ensuring the service life of the hybrid multi-level inverter; further, the rotation of the outer frame is triggered by the negative pressure value in the annular protrusion, and there is no need to consider the misjudgment caused by the failure of the detection element, thereby ensuring the reliability of the switching of the filter block between the air inlet and the air outlet.

[0019] Preferably, counterweights are provided on both the front and rear side walls of the inner frame, and the counterweights are located in the lower 1 / 4 area of ​​the front and rear side walls of the inner frame. When the outer frame is in an inclined state, by providing counterweights on the front and rear side walls of the inner frame, the center of gravity of the inner frame and the filter block moves downward, which is conducive to the inner frame sliding in the inclined direction of the outer frame, and improves the switching speed of the filter block in the water absorption saturated area and the unsaturated area, thereby ensuring the drying effect of the filter block on the gas entering the shell, thereby ensuring the drying of the gas in the shell, and ensuring the service life of the hybrid multi-level inverter.

[0020] Preferably, a type-one guide plate is provided on the outer side of the air inlet, and the type-one guide plate is arranged downwardly inclined with respect to the outer side wall of the shell, and a type-two guide plate is provided on the outer side of each of the two air outlets, and the type-two guide plate is arranged upwardly inclined with respect to the outer side wall of the shell.

[0021] Since the air inlet and the air outlet are both located on the same side wall of the shell, even if the high-temperature positive-pressure gas discharged from the shell will float upward after being discharged from the air outlet, it is easy to cause the high-temperature positive-pressure gas discharged from the air outlet to flow back into the air inlet and flow into the shell again, resulting in a reduction in the heat dissipation effect of the hybrid multilevel inverter; for this reason, a type-one guide plate is provided on the outer side of the air inlet, and a type-two guide plate is provided on the outer side of the air outlet, so that the high-temperature positive-pressure gas discharged from the air outlet flows toward the upper side of the hybrid multilevel inverter under the guiding effect of the type-two guide plates, and the The gas entering the air inlet is low-temperature gas on the lower side of the hybrid multilevel inverter, thereby preventing the high-temperature positive-pressure gas discharged from the air outlet from flowing back into the air inlet, thereby ensuring the heat dissipation effect of the hybrid multilevel inverter; not only that, the gas discharged from the two air outlets is positive-pressure gas, which prevents dust and water mist in the environment from entering the shell through the air outlet, thereby ensuring the cleanliness of the inside of the shell; and the inclination direction of the first-type guide plate on the outer side of the air inlet is downward, which prevents sand, water droplets, and suspended particles in the air from flowing toward the air inlet, thereby ensuring the cleanliness of the air inlet.

[0022] Preferably, the filter block comprises two filter layers, two water absorbing layers and a support layer, the two water absorbing layers are respectively located on the left and right side walls of the support layer, and the two filter layers are respectively located on the side walls of the water absorbing layers on both sides away from the support layer.

[0023] The filter block is configured to be composed of a filter layer, a water absorbing layer and a support layer. The support layer may be a skeleton structure made of aluminum alloy material, engineering plastic or carbon fiber material, thereby preventing the filter block from being deformed after absorbing water, thereby ensuring the outer dimensions and shape of the filter block; the water absorbing layer may be a porous structure made of at least any one of highly absorbent resin, bamboo fiber or activated carbon material, thereby ensuring the water absorption performance of the water absorbing layer and the air permeability of the water absorbing layer; the filter layer may be a filter mesh structure made of metal, fiber or resin, thereby preventing dust in the air from being retained in the water absorbing layer and reducing the water absorption performance of the water absorbing layer, thereby ensuring the water absorption performance of the filter block, thereby ensuring the dryness of the gas in the shell, and ensuring the service life of the hybrid multi-level inverter.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention ensures the drying of the gas entering the housing by arranging a water-absorbent filter block between the cooling fan and the housing. At the same time, by slidingly connecting the filter block in an outer frame rotatably connected to the housing, and arranging a switching component to drive the outer frame to rotate, when the water absorption in the original air inlet area of ​​the filter block reaches a saturated state, the switching component drives the outer frame to rotate, and the filter block slides in the inclined outer frame, thereby realizing the switching of the filter block between the water absorption saturated area and the unsaturated area, ensuring the drying effect of the filter block on the gas entering the housing, thereby ensuring the drying of the gas in the housing, and ensuring the service life of the hybrid multi-level inverter.

[0026] 2. The present invention sets a slide rail, a slider, an air valve and an on-off switch as a switching switch for driving the outer frame to rotate. When the water content of the filter block increases, the negative pressure between the cooling fan and the filter block increases, and the slider is driven to slide by the negative pressure. The lever on the slider drives the outer frame to rotate, thereby completing the switching of the filter block between the water absorption saturated area and the unsaturated area, ensuring the drying effect of the filter block on the gas entering the shell, thereby ensuring the drying of the gas in the shell, and ensuring the service life of the hybrid multi-level inverter.

[0027] 3. The present invention reduces the resistance of the filter block when switching between the water absorption saturated area and the unsaturated area by providing a sealing ring and a ball head support rod, thereby improving the rapid switching of the filter block between the water absorption saturated area and the unsaturated area, ensuring the drying effect of the filter block on the gas entering the shell, thereby ensuring the dryness of the gas in the shell and ensuring the service life of the hybrid multi-level inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the overall appearance of the hybrid multi-level inverter of the present invention;

[0029] Figure 2 It is an overall exploded view of the hybrid multi-level inverter of the present invention;

[0030] Figure 3 An exploded view of a heat dissipation module in a hybrid multi-level inverter of the present invention;

[0031] Figure 4 It is a right side view of the heat dissipation module in the hybrid multi-level inverter of the present invention;

[0032] Figure 5 for Figure 4 Sectional view at AA in the figure;

[0033] Figure 6 for Figure 5 The cross-sectional view at BB in FIG.

[0034] Figure 7 for Figure 4 Schematic diagram after removing the outer frame, inner frame and filter block;

[0035] Figure 8 It is a state diagram when the heat dissipation module in the hybrid multi-level inverter of the present invention switches from the R1 area to the R2 area;

[0036] Fig. 9 This is a state diagram of the heat dissipation module in the hybrid multi-level inverter of the present invention when it is about to switch from the R2 area to the R1 area;

[0037] Fig.10 This is a state diagram of the heat dissipation module in the hybrid multi-level inverter of the present invention when it switches from the R2 region to the R1 region.

[0038] In the figure: 1. shell; 101. air inlet; 102. air outlet; 103. type I guide plate; 104. type II guide plate; 2. fan; 3. mounting seat; 301. arc-shaped protrusion; 302. annular protrusion; 3021. connecting hole; 4. sealing ring; 5. slide rail; 501. slideway; 502. limit hole; 6. slider; 601. lever; 7. air valve; 8. on-off switch; 9. outer frame; 901. mounting hole; 902. arc-shaped groove; 903. slide groove; 10. inner frame; 1001. ball head support rod; 1002. counterweight block; 11. filter block; 1101. filter layer; 1102. water absorption layer; 1103. support layer. DETAILED DESCRIPTION

[0039] The following is combined with Figure 1 To Attachment Fig.10A specific implementation process of a hybrid multilevel inverter provided by the present invention will be described. It should be noted that for the convenience of description, in the following content, the front side and the rear side are the -Y and +Y directions respectively, the left side and the right side are the -X and +X directions respectively, the upper side and the lower side are the +Z and -Z directions respectively. At the same time, the filter block 11 is set as the R1 partition and the R2 partition, where the R1 partition and the R2 partition have the same area and are symmetric front and back.

[0040] Please refer to Figures 1 to 3 , a hybrid multilevel inverter, including a housing 1, a cooling fan 2 and a filter block 11. A circuit system is arranged inside the housing 1. Specifically, the air flow direction of the cooling fan 2 is from the air inlet 101 to the inside of the housing 1. There is one air inlet 101 and two air outlets 102 on the side wall of the housing 1. There is a type-I deflector 103 outside the air inlet 101, and the type-I deflector 103 is arranged obliquely downward with respect to the outer side wall of the housing 1. There are type-II deflectors 104 outside both air outlets 102, and the type-II deflectors 104 are arranged obliquely upward with respect to the outer side wall of the housing 1. An installation seat 3 is arranged on the inner side wall of the housing 1. The installation seat 3 has a "C"-shaped structure with an installation groove on one side, and the installation groove faces the air inlet 101. The cooling fan 2 is installed on the side wall of the installation seat 3. Ventilation holes concentric with the air duct of the cooling fan 2 are opened on the side wall of the installation seat 3. The side projection of the ventilation holes is completely located inside the air inlet 101, and the side projection of the cooling fan 2 is completely located inside the air inlet 101. An arc-shaped protrusion 301 is arranged in the middle of the bottom wall of the installation groove, and the center line of the arc-shaped protrusion 301 is parallel to the center line of the cooling fan 2.

[0041] Further, please refer to Figures 2 to 5 , an outer frame 9, an inner frame 10 and a filter block 11 are arranged in the installation groove. An arc-shaped groove 902 is opened in the middle of the lower end surface of the outer frame 9, and the arc-shaped groove 902 is rotatably connected with the arc-shaped protrusion 301. There is a movable gap between the lower end surface of the outer frame 9 and the bottom wall of the installation groove. Installation holes 901 are opened in the outer frame 9. The inner frame 10 is arranged in the installation holes 901. The filter block 11 is installed in the inner frame 10 with an interference fit. Counterweight blocks 1002 are arranged on the front and rear side walls of the inner frame 10, and the counterweight blocks 1002 are located in the lower 1 / 4 area of the front and rear side walls of the inner frame 10. The filter block 11 includes two filter layers 1101, two water absorption layers 1102 and one support layer 1103. The two water absorption layers 1102 are respectively located on the left and right side walls of the support layer 1103, and the two filter layers 1101 are respectively located on the side walls of the two water absorption layers 1102 far from the support layer 1103.

[0042] Even further, please refer to Figure 4 and Figure 5, the upper and lower inner walls of the outer frame 9 are both provided with slide grooves 903, and the slide grooves 903 are rectangular. The upper and lower outer walls of the inner frame 10 are respectively provided with a plurality of ball head support rods 1001, one end of the ball head support rod 1001 is fixedly connected to the inner frame 10, and the other end is slidably connected to the inner wall of the slide groove 903. The end of the ball head support rod 1001 that is slidably connected to the slide groove 903 is in the shape of a ball head, and the diameter of the ball head is equal to the width of the slide groove 903; the lateral projections of the air inlet 101 and the air outlet 102 are both located in the mounting hole 901, and the lateral projection of the filter block 11 covers the air inlet 101 and one air outlet 102; an annular protrusion 302 is provided in the mounting groove, and the annular protrusion 302 is coaxial with the ventilation hole, and a sealing ring 4 is coaxially provided on an end surface of the annular protrusion 302 close to the filter block 11, and the sealing ring 4 is slidably connected to the filter block 11.

[0043] Further, see Figures 5 to 7 A switching assembly for driving the outer frame 9 to rotate is provided in the mounting groove, and the switching assembly includes a slide rail 5, a slider 6, two air valves 7 and two on-off switches 8. The slide rail 5 is provided in the mounting groove, and a circular slideway 501 is provided in the slide rail 5, and the track of the slideway 501 is an arc. The slider 6 is slidably connected in the slideway 501. A limiting hole 502 is symmetrically provided on one end surface of the slide rail 5 close to the filter block 11, and the limiting hole 502 is communicated with the slideway 501. Two levers 601 are symmetrically provided on the slider 6. Both levers 601 extend outside the limiting hole 502, and both levers 601 are tangent to the upper end surface of the outer frame 9. The two air valves 7 are respectively arranged at both ends of the slide rail 5, and both air valves 7 are connected to the slide rail 501. Two connecting holes 3021 are symmetrically provided on the inner side wall of the annular protrusion 302, and the two air valves 7 are respectively connected to the two connecting holes 3021. The two channel switches are symmetrically arranged on the left and right sides of the upper end surface of the mounting seat 3, and the two on-off switches 8 are electrically connected to the two air valves 7.

[0044] See also Figures 1 to 10 , the working process of the hybrid multilevel inverter is as follows:

[0045] Start cooling fan 2 to Fig.10The state is the state of the outer frame 9 when the cooling fan 2 is started. At this time, the R1 area of ​​the filter block 11 is located at the air inlet 101, the R2 area of ​​the filter block 11 is located at the air outlet 102 on the rear side, the front air outlet 102 is in a fully open state, the front on-off switch 8 is triggered, the front air valve 7 is in a passing state, and the rear air valve 7 is in a closed state; when the cooling fan 2 is working, the annular protrusion 302 is in a negative pressure state, and the gas outside the shell 1 flows toward the cooling fan 2 under the action of negative pressure. The gas needs to pass through the R1 area of ​​the filter block 11 during the flow process. The water vapor in the gas entering the filter block 11 is absorbed by the R1 area of ​​the filter block 11, and the gas dried by the filter block 11 reaches the air duct of the cooling fan 2. , and then blown to the inside of the shell 1 by the air duct of the cooling fan 2. At this time, the shell 1 is in a positive pressure state, and the positive pressure gas is discharged to the outside of the shell 1 through the gap between the air outlet 102 and the shell 1. At the same time, the positive pressure gas discharges the heat generated by the circuit system to the outside of the shell 1; as the running time of the cooling fan 2 becomes longer, the water content in the R1 area of ​​the filter block 11 increases, the negative pressure value in the annular protrusion 302 increases, and the front slide 501 is in a negative pressure state. The slider 6 slides counterclockwise along the central axis of the slide 501 under the action of the negative pressure, and the lever 601 slides with the slider 6. At the same time, the lever 601 slides with the upper surface of the outer frame 9, and the outer frame 9 rotates counterclockwise around the central axis of the arc groove 902. The outer frame 9 first rotates counterclockwise to the adjacent Figure 4 State, as the slider 6 continues to slide, the outer frame 9 continues to rotate counterclockwise around the central axis of the arc groove 902 until the lower end surface of the outer frame 9 contacts the bottom wall of the mounting groove. During the process, the inner frame 10 slides toward the front side of the mounting hole 901 under the action of gravity until the front end surface of the inner frame 10 fits the front wall of the mounting hole 901, the inner frame 10 stops sliding, the on-off switch 8 on the rear side is triggered, the air valve 7 on the rear side is in the through state, the air valve 7 on the front side is in the closed state, the R2 area of ​​the filter block 11 is located at the air inlet 101, the R1 area of ​​the filter block 11 is located at the air outlet 102 on the front side, and the air outlet 102 on the rear side is in a fully open state, see the attached Figure 8 state.

[0046] The cooling fan 2 continues to work, and the annular protrusion 302 is in a negative pressure state. The gas outside the shell 1 flows toward the cooling fan 2 under the action of negative pressure. The gas needs to pass through the R2 area of ​​the filter block 11 during the flow process. The water vapor in the gas entering the filter block 11 is absorbed by the R2 area of ​​the filter block 11. The gas dried by the filter block 11 reaches the air duct of the cooling fan 2, and then blows toward the inside of the shell 1 through the air duct of the cooling fan 2. At this time, the inside of the shell 1 is in a positive pressure state, and the positive pressure gas is discharged to the outside of the shell 1 through the gap between the air outlet 102 and the shell 1. At the same time, the positive pressure gas discharges the heat generated by the circuit system to the outside of the shell 1. The high-temperature positive-pressure gas through the front air outlet 102 evaporates the moisture in the R1 area of ​​the filter block 11 and discharges it out of the front air outlet 102; as the running time of the cooling fan 2 becomes longer, the moisture content in the R2 area of ​​the filter block 11 increases, the negative pressure value in the annular protrusion 302 increases, and the rear slide 501 is in a negative pressure state. The slider 6 slides clockwise along the central axis of the slide 501 under the action of the negative pressure, and the lever 601 slides with the slider 6. At the same time, the lever 601 slides with the upper surface of the outer frame 9, and the outer frame 9 rotates clockwise around the central axis of the arc groove 902. The outer frame 9 first rotates clockwise to the adjacent Fig. 9 State, as the slider 6 continues to slide, the outer frame 9 continues to rotate clockwise around the central axis of the arc groove 902 until the lower end surface of the outer frame 9 contacts the bottom wall of the mounting groove. During the process, the inner frame 10 slides toward the rear side of the mounting hole 901 under the action of gravity until the rear end surface of the inner frame 10 fits with the rear wall of the mounting hole 901, the inner frame 10 stops sliding, the on-off switch 8 on the front side is triggered, the air valve 7 on the front side is in the through state, the air valve 7 on the rear side is in the closed state, the R1 area of ​​the filter block 11 is located at the air inlet 101, the R2 area of ​​the filter block 11 is located at the air outlet 102 on the rear side, and the air outlet 102 on the front side is in a fully open state.

[0047] A specific embodiment of the present invention is described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above described embodiment. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments without departing from the principles and ideas of the present invention should still fall within the scope of protection of the present invention.

Claims

1. A hybrid multilevel inverter, comprising a housing (1), a cooling fan (2) and a filter block (11), wherein a circuit system is arranged in the housing (1), characterized in that: A side wall of the housing (1) is provided with an air inlet (101) and two air outlets (102). The air inlet (101) is located between the two air outlets (102). The cooling fan (2) is connected to the inner side wall of the housing (1), and a side projection of the cooling fan (2) is completely located within the air inlet (101). An outer frame (9) is provided between the cooling fan (2) and the housing (1). The outer frame (9) is rotatably connected to the housing (1). An installation hole (901) is formed in the outer frame (9). The filter block (11) is slidably installed in the installation hole (901). Lateral projections of the air inlet (101) and the air outlets (102) are both located within the installation hole (901). A lateral projection of the filter block (11) covers the air inlet (101) and one of the air outlets (102). The air flow direction of the cooling fan (2) is from the air inlet (101) blowing into the housing (1). A switching assembly for driving the outer frame (9) to rotate is provided on the inner side wall of the housing (1). The switching assembly is in communication with the air duct of the cooling fan (2).

2. A hybrid multilevel inverter according to claim 1, characterized in that: An installation seat (3) is provided on the inner side wall of the housing (1). The installation seat (3) has a "C"-shaped structure with an installation groove on one side. The installation groove faces the air inlet (101). The cooling fan (2) is installed on the side wall of the installation seat (3). A ventilation hole concentric with the air duct of the cooling fan (2) is formed in the side wall of the installation seat (3). A lateral projection of the ventilation hole is completely located within the air inlet (101). An arc-shaped protrusion (301) is provided in the middle of the bottom wall of the installation groove, and the center line of the arc-shaped protrusion (301) is parallel to the center line of the cooling fan (2). The outer frame (9) and the filter block (11) are arranged in the installation groove. An arc-shaped groove (902) is formed in the middle of the lower end surface of the outer frame (9). The arc-shaped groove (902) is rotatably connected to the arc-shaped protrusion (301), and a movable gap is provided between the lower end surface of the outer frame (9) and the bottom wall of the installation groove.

3. A hybrid multilevel inverter according to claim 2, characterized in that: A ring-shaped protrusion (302) is provided in the installation groove. The ring-shaped protrusion (302) and the ventilation hole are coaxial. A sealing ring (4) is coaxially arranged on an end surface of the ring-shaped protrusion (302) close to the filter block (11). The sealing ring (4) is slidably connected to the filter block (11).

4. The hybrid multilevel inverter according to claim 2, characterized in that: An inner frame (10) is provided between the outer frame (9) and the filter block (11). The filter block (11) is installed in the inner frame (10) with an interference fit. Slide grooves (903) are provided on the upper and lower inner side walls of the outer frame (9). The slide grooves (903) are rectangular. A plurality of ball-headed support rods (1001) are respectively provided on the upper and lower outer side walls of the inner frame (10). One end of the ball-headed support rod (1001) is fixedly connected to the inner frame (10), and the other end is slidably connected to the inner wall of the slide groove (903). The end of the ball-headed support rod (1001) slidably connected to the slide groove (903) is ball-shaped, and the diameter of the ball is equal to the width of the slide groove (903).

5. The hybrid multilevel inverter according to claim 3, characterized in that: The switching assembly comprises a slide rail (5), a slider (6), two air valves (7) and two on-off switches (8); the slide rail (5) is arranged in a mounting groove; a circular slideway (501) is provided in the slide rail (5); and the track of the slideway (501) is an arc; the slider (6) is slidably connected in the slideway (501); a limiting hole (502) is symmetrically provided on an end surface of the slide rail (5) close to the filter block (11); the limiting hole (502) is communicated with the slideway (501); two shifting rods (601) are symmetrically provided on the slider (6); and the two shifting rods (601) are connected to the filter block (11). 1) both extend outside the limiting hole (502), and the two shifting rods (601) are both tangent to the upper end surface of the outer frame (9), the two air valves (7) are respectively arranged at the two ends of the slide rail (5), and the two air valves (7) are both connected to the slide rail (501), two connecting holes (3021) are symmetrically opened on the inner side wall of the annular protrusion (302), the two air valves (7) are respectively connected to the two connecting holes (3021), the two channel switches are symmetrically arranged on the left and right sides of the upper end surface of the mounting seat (3), and the two on-off switches (8) are electrically connected to the two air valves (7).

6. The hybrid multilevel inverter according to claim 4, characterized in that: Counterweight blocks (1002) are provided on both the front and rear side walls of the inner frame (10), and the counterweight blocks (1002) are located in the lower 1 / 4 area of ​​the front and rear side walls of the inner frame (10).

7. The hybrid multilevel inverter according to claim 1, characterized in that: A first-type guide plate (103) is provided on the outside of the air inlet (101), and the first-type guide plate (103) is arranged to be inclined downward with respect to the outer wall of the shell (1); and a second-type guide plate (104) is provided on the outside of the two air outlets (102), and the second-type guide plate (104) is arranged to be inclined upward with respect to the outer wall of the shell (1).

8. The hybrid multilevel inverter according to claim 1, characterized in that: The filter block (11) comprises two filter layers (1101), two water absorption layers (1102) and a support layer (1103), wherein the two water absorption layers (1102) are respectively located on the left and right side walls of the support layer (1103), and the two filter layers (1101) are respectively located on the side walls of the water absorption layers (1102) on both sides away from the support layer (1103).

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