CN201623650U - A Modular Mounted Inverter - Google Patents

Abstract

The utility model discloses an inverter with modularized installation, which particularly relates to an inverter with modularized installation. The inverter with modularized installation comprises a three-phase filtering capacitor, an inversion power tube and a laminated busbar, wherein the three-phase filtering capacitor is connected on the laminated busbar in series and in parallel and then is connected with the inversion power tube in parallel, and the laminated busbar structure is a cascaded copper bar installed between a cathodic copper bar and an anodic copper bar. The inverter realizes modularization and is more beneficial to integration, the laminated busbar and the three-phase filtering capacitor are combined as a module which is directly in nearby connection with the three-phase inversion power tube, the problem of low utilization rate of a traditional inverter is overcome, and a three-phase main circuit has better parameter uniformity. The laminated busbar adopts a large-area symmetrical structure, and the stray inductance of a line is lowered. Low-inductance damping absorption capacitors are directly stuck at both ends of the inversion power tube, which enhances the damping absorption capability effectively. A heat insulating plate isolates a power component and the filtering capacitor, lowers the influence of the heat radiation of the power tube to the filtering capacitor and prolongs the service life.

Description

A Modular Mounted Inverter

technical field

The utility model relates to an inverter connection structure, in particular to a modularized inverter.

Background technique

At present, in the design of three-phase inverter products, in order to achieve a high degree of product integration, most of its unit components adopt modular design. As shown in Figure 1, in the existing inverter, the filter capacitor module of each phase is directly connected in parallel with the inverter power tube nearby, and the three phases connected in parallel are then connected together and connected to the DC power supply, which is designed in this way The main circuit structure of the inverter, due to the long connection line, large distributed inductance, and due to the dispersion of capacitance, the utilization rate of the DC filter capacitor is low; for example, when the A-phase inverter power tube is working, only the A-phase filter capacitor Participate in the work and provide the required energy, and the filter capacitors of phase B and phase C contribute less.

As shown in Fig. 2, in the connection mode of the filter capacitor in the prior art, the DC laminated busbar of the inverter device mostly adopts a single set of power modules. In this design scheme, the filter capacitor of a single set of power The inverter power tube modules are connected in parallel nearby, and then connected to the DC power supply; due to the inconsistency of module parameters and the existence of stray inductance in the connecting circuit, the overshoot voltage of the inverter power tube will be increased, and at the same time, in order to solve the power module parameters The problem of matching will also increase the cost of the design. Since the three-phase filter capacitor banks cannot be connected in parallel nearby, they cannot jointly bear the output power of the entire inverter. The current that the module can withstand will be greatly limited. The separate design of the three phases makes the volume of the inverter larger, which is not conducive to compact and modular design.

Utility model content

In order to solve the problems of many interconnection leads, complex structure and large parasitic inductance among inverter power devices in the prior art, the utility model provides a method of integrating the filter capacitors of three bridge arms on a laminated busbar to An inverter that can withstand greater voltage and current and improve the utilization of filter capacitors. The specific plan is as follows: A modular inverter includes three-phase filter capacitors, inverter power tubes and laminated busbars. It is characterized in that the three-phase filter capacitor is connected in series and parallel on the laminated busbar and then connected in parallel with the inverter power tube.

Another preferred mode of the present invention: the laminated busbar includes a negative copper bar, a positive copper bar and a cascaded copper bar, the cascaded copper bar is installed between the negative copper bar and the positive copper bar, and the negative copper bar Insulating plates are installed on the contact surfaces of the positive copper bar and the cascaded copper bar.

Another preferred mode of the present invention: low-inductance buffer absorption capacitors are installed at both ends of the inverter power tube.

Another preferred mode of the present utility model: a radiator is installed on the inverter power tube.

Another preferred mode of the present utility model: a heat shield is installed between the inverter power tube and the three-phase filter capacitor.

Another preferred mode of the present utility model: a radial fan is installed on one side of the radiator.

The inverter of the utility model realizes modularization, which is more conducive to integration. The capacitor bank and the laminated busbar are used as a module, the inverter power tube and the radiator are used as a module, and the fan is used as a module, which simplifies the assembly of the main circuit and is convenient. Easy to install. The laminated busbar and the three-phase filter capacitor bank are directly connected to the three-phase inverter power tube as a module, which overcomes the problem of low utilization of the traditional inverter, and the three-phase main circuit parameters are consistent. The laminated busbar adopts a large-area symmetrical structure, which reduces the stray inductance of the line. The low-inductance buffer absorption capacitor is directly attached to both ends of the inverter power tube, which effectively improves the buffer absorption capacity. The heat shield separates the power device and the filter capacitor group, which reduces the influence of the heat dissipation of the power tube on the filter capacitor and prolongs the service life. The radial flow fan is used for heat dissipation, and the centrifugal flow guide method is directly connected to the radiator, which shortens the air duct and increases the heat dissipation effect.

Description of drawings

The connection circuit diagram of the three-phase capacitor module and the inverter power tube module in the prior art in Fig. 1

Fig. 2 Schematic diagram of the connection between the positive copper bar and the negative copper bar of the three-phase capacitor module in the prior art

Fig. 3 is the connection circuit diagram of the three-phase capacitor module and the inverter power tube module in the utility model

Figure 4 is a schematic diagram of the connection between the positive copper bar and the negative copper bar of the three-phase capacitor module in the utility model

Fig. 5 is a top view structural diagram of the positive copper bar and the negative copper bar of the three-phase capacitor module of the utility model

Figure 6 is a schematic diagram of the utility model cooling device

Fig. 7 is a schematic diagram of the fan in the heat dissipation device of the present utility model

Detailed ways

The main circuit of the modularized inverter of the utility model mainly includes: an inverter power tube module, a radiator 7, a radial fan 8, a filter capacitor group, a stacked busbar, and the filter capacitor group is composed of a plurality of three-phase filter capacitors 4 connected in series , the filter capacitor bank is directly connected to the laminated busbar, one end of the laminated busbar is directly connected to the DC power supply, and the other end is respectively connected to the CE poles of the three inverter power tubes, so that all filter capacitors are directly connected in parallel with the inverter power tubes , which can effectively reduce the ripple current between capacitors; the radial fan 8 is directly connected to the radiator 7 of the inverter power tube, which can reduce the length of the air duct while ensuring the sealing, so that the heat dissipation effect is significantly increased; low inductance buffer The absorption capacitor 9 is directly attached to both ends of the CE pole of the inverter power tube, so it has a good buffer effect and can protect the safe operation of the inverter power tube to the greatest extent. The heat shield 10 separates the radiator and the filter capacitor. The influence of heat dissipation of the inverter power tube on the filter capacitor is reduced.

As shown in Figure 3, the three-phase filter capacitors 4 of the present invention are firstly connected in series on the same laminated busbar, and then the laminated busbar is connected in parallel with the inverter power tube. In this connection mode, the A-phase filter capacitor group C1 can not only be used for A-phase power tube T1, but also for B-phase power tube T2 and C-phase power tube T3. Similarly, B-phase filter capacitor group C2 and C-phase filter capacitor group C3 can also be used for other inverters At the same time, due to the large connection area between the filter capacitor banks, when the inverter power tube of any phase is working, all the filter capacitor banks can provide the required energy well.

As shown in Figure 4, the laminated busbars in this scheme are completely overlapped, and the filter capacitor is formed by connecting copper bars. The isolated insulating board 5, the positive copper bar and the negative copper bar are installed symmetrically, the cascaded copper bar is installed in the middle of the positive copper bar and the negative copper bar, and the isolation insulating board is installed between the positive copper bar and the negative copper bar and the cascaded copper bar on the contact surface. This structure can effectively reduce the stray inductance of the line and ensure the symmetry of the circuit, which is beneficial to reduce the reverse peak voltage at both ends of the power element, thereby reducing the requirements of the power device for the snubbing circuit and improving the reliability and stability of the power device operation At the same time, it improves the integration of the circuit, which is convenient for installation and maintenance.

As shown in FIG. 5 , the top view structure of the laminated busbar is provided with a power output interface and a DC/AC input interface on the negative copper bar 1 and the positive copper bar 3 .

As shown in Figures 6 and 7, the laminated busbars and three-phase inverter power tubes are connected in series, and the buffer absorption capacitor 9 is directly attached to both ends of the inverter power tube 6 to form a better buffer absorption effect and maximize the To protect the safe operation of the power tube, install a radiator 7 to dissipate heat from the inverter power tube 6, and install a heat shield 10 between the filter capacitor group and the inverter power tube to separate the radiator and the capacitor group, reducing the risk of damage caused by the inverter. The influence of the heating of the power tube on the filter capacitor 4 can prolong the service life of the filter capacitor. The radial flow fan 8 is directly connected to the radiator, which shortens the length of the air duct, and is easy to seal the air duct, thereby increasing the heat dissipation effect. The fan adopts radial flow fan 8, with centrifugal flow diversion, the air turbulence is significantly reduced, and the blind area formed by the traditional axial flow fan is overcome, and the noise value is also greatly lower than that of the axial flow fan. It has the characteristics of maintenance-free and long life. Moreover, the fan is directly connected to the radiator, which reduces the length of the air duct and is more conducive to heat dissipation.

Claims (6)

1. A modular inverter comprising three-phase filter capacitors (4), inverter power tubes (6) and laminated busbars, characterized in that the three-phase filter capacitors are connected in series and parallel to laminated busbars Then connect in parallel with the inverter power tube (6). 2. The inverter according to claim 1, characterized in that, the laminated busbars include negative copper bars (1), positive copper bars (3) and cascaded copper bars (2), and the cascaded The copper bar is installed between the negative copper bar and the positive copper bar, and an insulating plate (5) is installed on the contact surface of the negative electrode copper bar, the positive electrode copper bar and the cascaded copper bar. 3. The inverter according to claim 2, characterized in that, low-inductance buffer absorption capacitors (9) are installed at both ends of the inverter power tube. 4. The inverter according to claim 3, characterized in that a radiator (7) is installed on the inverter power tube. 5. The inverter according to claim 4, characterized in that a heat shield (10) is installed between the inverter power tube and the three-phase filter capacitor. 6. The inverter according to claim 5, characterized in that a radial fan (8) is installed on one side of the radiator.

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