JP3651406B2 - Power converter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power conversion device that controls the driving environment of a compressor motor using an inverter circuit in an air conditioner or the like.
[0002]
[Prior art]
Recent air conditioners are required to perform air conditioning with energy saving and high efficiency. In order to achieve this, it is important to improve the operating efficiency of the compressor, which is the main power source of the air conditioner.
[0003]
For this reason, a DC motor (brushless motor) is generally used for the compressor, and its rotation speed is varied according to the required load (deviation between the set temperature and room temperature) at that time. When the load is large, it is rotated at high speed.
[0004]
As a method for controlling the rotation speed of the compressor motor, control by an inverter circuit that converts a direct current into a pulse-width modulated (hereinafter referred to as PWM) signal that is a signal for driving the motor is known.
[0005]
Generally, the motor drive device used for an air conditioner is roughly divided into the following parts. That is, the motor drive device is mainly a rectifier (converter) that rectifies AC power input from a commercial power supply, a smoothing circuit that mainly smoothes the output of the rectifier, and a PWM for driving the motor with the output of the smoothing circuit. Compressor drive control circuit (hereinafter referred to as microcomputer control) having a microcomputer for supplying a switching signal to an inverter circuit for converting a signal and six switching elements (transistor, gate insulating bipolar transistor (IGBT)) constituting the inverter circuit Circuit), a noise filter consisting of a reactor and a capacitor that suppresses the noise generated by the inverter from flowing out to the commercial AC power supply side, a power factor improving circuit consisting of a reactor and a capacitor for improving the power factor, and driving the compressor Check the rotor magnetic pole position of the brushless motor (electric motor) And a compressor rotor magnetic pole position detector for.
[0006]
The rectifier circuit and the inverter circuit are each modularized by high-density mounting of the semiconductor elements constituting them, and are commercialized as general-purpose electric / electronic components such as diode stacks and power transistor modules.
[0007]
In general, an inverter module used in an air conditioner is for driving a compressor motor unlike other electronic components. Therefore, a high voltage of, for example, 100 V to 300 V is applied to a switching element constituting the inverter module, and a current near 20 A is applied. Since it flows, the element itself generates heat due to the internal resistance of the element.
[0008]
For this reason, in order to prevent element destruction due to temperature rise of these switching elements, it is common to use an aluminum cooling heat radiation fin attached to a module in which a plurality of switching elements are packaged.
[0009]
Other parts that do not require heat dissipation fins (compressor drive control circuit parts, etc.) are mounted on one or a plurality of printed wiring boards to form a board assembly. Since the radiating fins must be tightly fixed, the module and the board assembly are arranged separately, and the connection between the terminals is often performed using an electric wire or the like.
[0010]
As a prior art for simultaneously satisfying the omission of wiring and the close fixation with the radiating fin for the purpose of reducing the manufacturing cost, Japanese Patent Laid-Open No. 6-123449 (hereinafter referred to as Document 1) and Japanese Patent Laid-Open No. 8-86473 (hereinafter referred to as Document). 2) and a mounting structure described in Japanese Patent Laid-Open No. 10-267326 (hereinafter referred to as Document 3) are known.
[0011]
The mounting structure described in Document 1 will be described with reference to FIG. A photocoupler, a capacitor, a drive circuit, and the like are mounted on the power printed wiring board 103, and the inverter module 102 is disposed on the board surface opposite to the board surface on which these electronic components are mounted. Are mounted on the power printed wiring board 103 and electrically connected by soldering or the like. On the other hand, a separately formed molding board 106 is connected to the power printed wiring board 103. Although not denoted by reference numerals, the board provided on the electronic component mounting surface side of the power printed board 103 is a control board on which a microcomputer or the like is mounted. Then, by fixing the molded substrate 106 to the heat radiating fins 100, the heat radiating surface of the inverter module 102 mounted on the power printed wiring substrate 103 on the side opposite to the power printed wiring substrate 103 is closely fixed to the heat radiating fins. This achieves compactness and reduced wiring (no lead wires).
[0012]
Further, Document 2 uses a support for attaching the power module to the heat sink. The support is screwed to the anti-heat dissipating surface of the power module. This support is bent at both ends in the thickness direction of the power module and stretched in the power module thickness direction by the same length as the power module thickness, where both ends are bent in the direction opposite to the longitudinal direction of the power module. Thus, a screw allowance (region for forming a screw hole) is formed. Then, the power module is attached to the heat sink with screws so as to be sandwiched between the heat sink and the support.
[0013]
On the other hand, this support has a structure to which a printed wiring board is also attached. That is, the portion of the previous screw margin is extended in the short side direction of the power module, and is bent to the opposite side of the heat sink. A screw hole is formed in the bent portion, and a printed wiring board is screwed here. The electrical connection between the power module and the printed wiring board is provided on the side opposite to the heat sink of the power module, and a plurality of terminals extending in the direction of the printed wiring board attached to the support are provided in holes formed in the printed wiring board. It is done by being plugged in. As a result, the same effect as in Document 1 is obtained.
[0014]
In Document 3, a power module and other electronic control components are mounted on the same surface of a printed wiring board, and the printed wiring board is attached to a top cover to which a sheet sink is attached. The top cover is formed in a box shape with an insulating material, and is fitted into and engaged with the outer edge portion of the printed wiring board by the fitting engagement portion, so that the electronic component mounting surface of the printed wiring board is covered by the fitting engagement. It has become. And a power module is attached to the heat sink attached to the top cover so that it may be pinched | interposed into a printed wiring board and a heat sink. As a result, the same effects as in Document 1 can be obtained.
[0015]
By the way, recently, an inverter module equipped with a low-loss switching element has been developed aiming at high efficiency. In general, when the efficiency of a switching element is increased, the withstand time (short circuit withstand time) for an instantaneous inrush current (peak current) exceeding the rated value of the element, for example, in a short circuit accident, tends to be shortened. For this reason, there is a need for a protection circuit system that quickly detects a peak current within a short circuit withstand time (for example, 2 μs to 5 μs) and stops driving the inverter circuit.
[0016]
In order to perform the protection operation at high speed, the resistance component and reactance component of the wiring itself cannot be ignored. Therefore, the method of arranging the drive control circuit in the vicinity of the inverter bridge circuit is common. With the aim of miniaturization and systemization, modules that integrate inverter circuits, their drive control circuits, peak current protection circuits, etc., and put them in the same case have also appeared.
[0017]
[Problems to be solved by the invention]
In the structure described in Document 1, as shown in FIG. 8, not only the mass of the printed wiring board 103 is supported, but also the printed wiring board 103 is pressed down so that the heat radiation fins 100 and the module heat radiation surface 102a are brought into contact with each other. . For this reason, the connection terminal itself must be strengthened by increasing the diameter of the connection terminal 104 that is not electrically required.
[0018]
The molded board in FIG. 8 has an advantage in that it also has other electronic components mounted thereon, but as a result, a printed wiring board support is still required, and the number of parts accompanying the mounting of the module is much reduced. Absent.
[0019]
In particular, the structure is such that the module heat radiation surface 102a and the heat radiation fin 100 are indirectly brought into contact with each other by pressing the control board 103, so that an error in the height dimension of the support and an error in the height dimension of the module cause a gap between the module and the heat radiation fin. A gap is generated, and the heat of the module cannot be effectively transmitted to the heat radiating fins.
[0020]
As a method of effectively transferring the heat of the module 102 to the heat radiating fins 100, for example, there is a method in which silicon grease is applied to the gap between the module heat radiating surface 102a and the heat radiating fins 100. However, this is not necessarily a good solution because it increases costs and increases the coating process.
[0021]
If the printed wiring board 103 is strongly pressed with a screw or the like in order to improve the close contact with the radiating fin, stress is applied to the printed wiring board 103, the board is distorted, and a crack (solder crack) is generated in the solder portion. There is a possibility that the solder for electrically connecting the terminals of the module 102 and the printed wiring board 103 may come off.
[0022]
In other words, in order to maintain good adhesion between the power module 102 and the radiation fin 100 and prevent stress on the printed wiring board 103 or the solder portion of the power module 102 from being generated, It was necessary to increase the dimensional accuracy and improve the accuracy during installation.
[0023]
Similarly, the mounting structure described in Document 2 has a structure in which the power module is fixed between the support and the heat sink described above. Therefore, when the dimension for bending the support in the thickness direction of the power module is short. On the other hand, pressure is applied to the power module. On the other hand, if this dimension is long, there is a problem that the degree of adhesion between the heat radiation surface of the power module and the heat sink is deteriorated and heat radiation is not performed well.
[0024]
Furthermore, regarding the electrical connection between the connection terminal of the power module and the printed wiring board, the connection terminal of this power module is as weak as about φ0.8 mm, so the connection part between the connection terminal and the printed wiring board with the support bracket (especially the soldering part) ) Is protected from stress.
[0025]
However, although there are advantages in reducing the wiring cost of electric wires and the like and protecting the power module connection terminals, the accuracy of the mounting work of the support to the printed wiring board, the accuracy of the mounting work of the power module and the support, and the radiation fins ( There is a problem that the accuracy of mounting work between the heat sink) and the power module is required.
[0026]
Similarly, in the mounting structure described in Document 3, depending on the accuracy of the height of the side wall that defines the thickness of the top cover and the depth of soldering of the power module (where the terminal is to be soldered), There are problems such as poor adhesion between the heat radiation surface of the power module and the heat sink, and stress on the printed board on which the power module is mounted.
[0027]
Further, in the mounting structures described in Documents 1 and 3, the mass of the printed wiring board 103 is supported by two rows of connection terminals 104 as shown in FIG. For this reason, since the power module terminals are arranged in two rows, there is a problem in that the degree of freedom in designing the power module is limited, and the connection terminals 104 that are not electrically required are strengthened, resulting in an increase in cost.
[0028]
An object of the present invention is to provide a power conversion device having a mounting structure that improves the adhesion between a power module and a heat sink without increasing the accuracy and assembly accuracy of various components and does not apply unnecessary stress to components. .
[0029]
[Means for Solving the Problems]
The above purpose is equipped with an inverter circuit composed of a plurality of semiconductor switching elements. A substrate formed of a heat conductor, a resin module case in which the substrate is incorporated, a terminal provided in the module case and electrically connected to the inverter circuit, and a heat dissipation surface of the substrate are flat. A control board having a heat sink to which the module case is attached, a control circuit for driving the inverter bridge circuit, and a pin connector electrically connected to the control circuit; This control board This is achieved by providing a mechanism for fixing and electrically connecting the inverter circuit and the control circuit by coupling the terminal and the pin connector.
[0030]
The above purpose is equipped with an inverter circuit composed of a plurality of semiconductor switching elements. A substrate formed of a heat conductor, a resin module case in which the substrate is incorporated, a pin connector provided in the module case and electrically connected to the inverter circuit, and a heat dissipation surface of the substrate are flat A control board having a heat sink to which the module case is attached and a control circuit for driving the inverter bridge circuit and a terminal electrically connected to the control circuit; This control board This is achieved by providing a mechanism for fixing and electrically connecting the inverter circuit and the control circuit by coupling the pin connector and the terminal.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0036]
First, the inverter circuit which controls the rotation speed of the compressor motor which comprises a part of refrigeration cycle of an air conditioner is demonstrated using FIG.
[0037]
In FIG. 1, a power converter according to this embodiment includes a rectifier 2 (converter) that rectifies AC power input from a commercial AC power supply 5, a smoothing circuit 1 that mainly includes a capacitor that smoothes the output of the rectifier 2, The inverter circuit 3 that converts the output of the circuit 1 into a PWM signal for driving the electric motor 10, and the switching signal is supplied to the six switching elements 3 a (transistor, gate-insulated bipolar transistor (IGBT)) constituting the inverter circuit 3. Compressor drive control circuit 4 (hereinafter referred to as a microcomputer control circuit) having a microcomputer for carrying out, a noise filter 6 comprising a reactor and a capacitor for suppressing the noise generated by the inverter 3 from flowing out to the commercial AC power supply side, a power factor Power factor improvement circuit 7 consisting of a reactor and a condenser for improvement, driving the compressor And a compressor rotor magnetic pole position detector 9 for detecting a rotor magnetic pole position of the brushless motor (motor) that.
[0038]
A commercial AC power source 5 (in the case of a domestic air conditioner, connected to a power source by connecting a power plug to an outlet) is connected to the rectifier circuit 2 via a noise filter 6 and a power factor correction circuit 7. The rectifier circuit 2 converts alternating current into direct current, and obtains a direct-current voltage (Vd) between A and B of the smoothing circuit 1 connected to the rectifier circuit 2. This DC voltage is input to the DC side of the inverter circuit 3. The inverter circuit 3 includes six semiconductor switching elements 3a and free-wheeling diodes connected in antiparallel to the respective semiconductor switching elements 3a. By adjusting the average DC voltage applied to the compressor DC motor 10 according to the switching timing of the inverter circuit 3, the compressor rotational speed is controlled at a variable speed.
[0039]
The switching timing in the inverter circuit 3 is determined by the microcomputer control circuit 4, the rotor (not shown) magnetic pole position of the compressor motor 10 is detected by the magnetic pole position detector 9, and the microcomputer calculates based on the magnetic pole position signal. Then, the compressor drive signal corresponding to the operation state at that time is determined, and this is instructed to the inverter circuit 3, whereby the constituent switching element 3a of the inverter circuit 3 is turned on / off. This signal is applied to the stator winding of the compressor motor 10 to control the compressor motor at a variable speed.
[0040]
The compressor rotor magnetic pole position detection circuit 9 in FIG. 1 detects the magnetic pole position (direction) of the rotating compressor rotor (magnet). When the microcomputer control circuit 4 receives the detection signal, the microcomputer A switching command signal of the inverter circuit element 3a to be sent next is estimated after estimating the current rotor magnetic pole position.
[0041]
The inverter circuit element 3a is turned on and off in accordance with a command from the microcomputer to switch the direction of the current flowing to the compressor stator (commutation operation), whereby induction or repulsion is repeated between the rotor and the stator to continuously rotate. Done.
[0042]
In order to configure the compressor rotational speed control system as described above, in the present invention, specifically, a diode as a rectifier circuit element and an IGBT (Insulated Gate Bipolar-transistor) capable of high-speed switching as an inverter circuit element are used. It is going to be realized using a diode.
[0043]
The rectifier circuit 2 and the inverter circuit 3 are each modularized by high-density mounting of the semiconductor elements constituting them, and are commercialized as general-purpose electric / electronic components such as diode stacks and power transistor modules.
[0044]
Next, implementation of the power conversion apparatus shown in FIG. 1 will be described. 2 and 3 are examples showing a substrate dividing method in the power converter of the air conditioner shown in FIG. 1, FIG. 4 is an example of the module structure shown in FIG. 3, and FIG. 5 is the present embodiment. FIG. 6 and FIG. 7 show an example of this embodiment including the connection between the module and the other circuit board.
[0045]
Hereinafter, the concept of assembling individual components in consideration of assembly accuracy and heat dissipation when mounting the electric circuit according to the power conversion device shown in FIG. 1 will be described with reference to FIGS. 2 and 3.
[0046]
In the embodiment shown in FIG. 2, a separate printed wiring board is used to separate a rectification / inverter circuit unit 8 (hereinafter referred to as a power unit) and a main control unit 11 of a microcomputer control other circuit, and a semiconductor constituting the power unit. The elements are collectively mounted on the same substrate, and a module is manufactured by attaching external connection terminals and a built-in case to separate the elements from the heat generating elements. Another feature of this separation method is that the capacitors in the main circuit, that is, the capacitors constituting the noise filter 6, the capacitors constituting the power factor correction circuit 7, and the capacitors constituting the smoothing circuit 1 are collected. is there. Moreover, the reactor which comprises the power factor improvement circuit 7 was made independent.
[0047]
In order to improve the heat dissipation of the printed wiring board used in the module, the heat generated by the semiconductor element mounted on the substrate pattern surface is dissipated through the metal plate by adopting, for example, a metal substrate using aluminum as the substrate base.
[0048]
Further, by mounting the rectifier circuit 2 and the inverter circuit 3 on the same substrate, it is possible to reduce the cost by omitting wiring work by electric wires and the like, and the heat generation sources can be concentrated at one place, so that the heat sink can be shared. Therefore, it is possible to arrange the substrate without waste.
[0049]
On the other hand, the electronic components of the main control unit other than the module are mounted on two printed wiring boards 11 (hereinafter referred to as main boards) so as to suppress wiring costs such as electric wires generated by the division as much as possible.
[0050]
The module 8 and the main board 11 are connected and fixed at a lower cost than in the past by the respective mounting structures described later.
[0051]
Here, in the case of FIG. 2, the substrate is divided mainly for cost reduction by omitting the wiring, but as described above, the noise filter 6 and the power factor correction circuit are provided on the single substrate in the main substrate 11. 7 is a circuit that handles a high voltage (high electric circuit) and an electronic circuit (weak electric circuit) such as a microcomputer that operates at 5 V, for example. However, in consideration of the influence of noise and safety, the high-power circuit portion and the weak-power circuit portion may be separated into three parts, that is, divided into an input power source unit such as a power unit and a noise filter, and a microcomputer control unit.
[0052]
In order to improve versatility, the rectifier circuit unit 2 may be separated from the module 8, and an inverter drive circuit, an inverter protection circuit, a microcomputer, etc. may be incorporated in the module 8 as shown in FIG.
[0053]
In short, as long as the module structure described later is devised, the system can be designed in accordance with the storage space for electrical products and the required performance, regardless of the substrate division method.
[0054]
The embodiment of the division method according to the present invention shown in FIG. 3 is not only advantageous in terms of versatility, but also arranges an inverter protection circuit such as overcurrent in the vicinity of the inverter circuit. Thus, the high-speed protection operation described in the conventional example can be realized, which is advantageous in terms of improving reliability. The power input circuit board 13 is equipped with a noise filter 6 and a capacitor and smoothing circuit 1 which are one of the components of the power factor correction circuit 7, and the module board 12a has a rectifier circuit 2, an inverter circuit 3 and a rotor magnetic pole position detection. The microcomputer 9 is mounted, and the microcomputer control circuit 4 including the above-described protection circuit is mounted on the microcomputer control board 12b.
[0055]
FIG. 4 is a cross-sectional view showing an example of the connection between the module structure according to an embodiment of the present invention and other control boards in the board division configuration shown in FIG.
[0056]
In FIG. 4, 12a is an aluminum substrate, 14 is a module case processed by resin molding such as PPS, 12b is a microcomputer control board mounted with a microcomputer, and 15 is a microcomputer processed by resin molding such as ABS for supporting the mass of the microcomputer control board 12b. A board case 13 is a board on which a power supply circuit for supplying a control DC voltage source for driving a microcomputer, such as a noise filter and 5 V output, is mounted. Here, a cable 21 is used to electrically connect to the microcomputer board 12b. doing.
[0057]
Among these, the upper surface of the aluminum substrate 12a is provided with a copper foil serving as a conductive portion with an insulating layer sandwiched in an arbitrary print pattern, which serves as a component mounting surface of the substrate.
[0058]
An inverter and a rectifier circuit component semiconductor element 16 is mounted on a component mounting surface of the aluminum substrate 12a, and each module is connected via a copper foil pattern to form a module with a module case 14 incorporating connection input / output terminals 17a and 17b. doing.
[0059]
On the other hand, heat radiation of the module is performed by aligning the heat radiation surface of the aluminum substrate 12a and the plane of the aluminum heat radiation fin 18 and directly fixing the module to the aluminum heat radiation fin 18 via the module case 14 using screws or the like. .
[0060]
As a result, the module-specific support bracket is not used and the switching element 3a and the microcomputer control board 12b that constitute the inverter circuit 3 are not stacked, which is unnecessary for the microcomputer control board 12b and the switching element 3a. Since the module and the radiating fin 18 are in direct contact with each other without applying stress, there is no gap between the module and the radiating fin 18 due to an error such as a height dimension, and the heat of the module is surely secured. Therefore, the heat radiation fin 18 can be transmitted to effectively dissipate heat, and the module, that is, the component 16 can be prevented from being destroyed due to a temperature rise.
[0061]
By the way, in the present embodiment, the connection terminals of the module case 14 in FIG. 4 are a large terminal 17a for handling a high voltage and a large current connected to the compressor motor 10 as shown in the figure, and an inverter element. The large terminal 17a can be connected directly to the cable 19 extending from the compressor.
[0062]
As a result, it is not necessary to pass a high-voltage, high-current circuit in the vicinity of an electronic component that operates at a low voltage, so that malfunction due to noise can be prevented.
[0063]
Further, 12b in FIG. 4 is a microcomputer control board on which a microcomputer and an inverter drive control circuit are mounted. A pin connector 20 to be connected to a control signal pin 17b to the module is mounted on this board and incorporated in the microcomputer board case 15. Yes.
[0064]
At this time, the module case 14 is provided with a mechanism 14b for fixing the microcomputer control board 12b, and the module and the microcomputer control board 12b are connected and fixed by the mounting mechanism 14b.
[0065]
For this reason, it is not necessary to use the dedicated support bracket or module terminal to fix the substrate as in the above-described conventional example, so that the signal connection terminals 17b of the module can also be arranged in only one row as shown in this figure.
[0066]
In the present embodiment, the module case 14 and the microcomputer board case 15 are made independent, and the module case 14 fixes even the mass of the switching element, and the microcomputer board case 15 supports the mass of the microcomputer control board 12b. Due to the structure, the processing accuracy of the support for supporting the microcomputer control board 12b and the semiconductor switch element is not good, the unnecessary stress described in References 1 to 3 is applied, the semiconductor switching element and the heat sink Occurrence of problems such as poor thermal contact can be prevented. As for the assembly, as will be described in detail with reference to FIGS. 5 and 6, electrical connection and mechanical coupling can be easily performed.
[0067]
In the present embodiment, the microcomputer board case 15 is separable independently from the module case 14, so that the design changes even if the microcomputer control circuit is changed or the board configuration other than the module is changed. It is possible to make it less so that it has general versatility.
[0068]
Of course, the substrate case 15 is provided in a form independent of the module case 14. However, the substrate case 15 may be integrated with the module case 14, and the versatility is sacrificed by the integration, but the number of work steps for incorporation is reduced. Leading to cost reduction.
[0069]
At this time, even if an integrated structure is used, a mechanism for supporting and fixing the microcomputer control board 15 is provided on the module side.
[0070]
5, FIG. 6 and FIG. 7 show an embodiment of the present invention showing details of the structure of the module case mounting mechanism and the microcomputer control board case mounting mechanism.
[0071]
In FIG. 5, the module case 14 and the microcomputer board case 15 are fitted to each other, so that the concavo-convex portions 22a and 22b can be easily assembled by sliding up and down. At this time, the plurality of module connection terminals 17b on the module case 14 side are inserted into the pin connector 20 provided on the microcomputer board case 15 side without applying an excessive force.
[0072]
Usually, the module case 14 and the control board case 15 are both produced by resin molding, and therefore, the embodiment takes advantage of the advantages of resin molding that can be designed in a free shape and that the shape can be finely adjusted.
[0073]
In the case of the embodiment shown in FIG. 6, the module case 14 and the microcomputer substrate case 15 are stacked one on top of the other and screwed and fixed through screw holes 23a and 23b previously provided on both sides.
[0074]
While the microcomputer control board 12b is incorporated in the microcomputer board case 15, as shown in the figure, the microcomputer control board 12b is moved up and down to connect the module connection terminal 17b using the connector pin 24.
[0075]
In the case of FIG. 6, since it is firmly fixed with screws or the like, it is advantageous in that it is possible to supply components (production for each block) while the module and the microcomputer board are connected.
[0076]
In the embodiment shown in FIG. 7, the microcomputer control board 12b is connected in the vertical direction in FIG. 6, but the module connection terminal 17b is arranged in the horizontal direction, and the microcomputer board 12b is also slid in the horizontal direction and connected. An example is shown.
[0077]
In the embodiment described above, the module connection terminal (input / output terminal) is provided on the module side and the pin connector is provided on the microcomputer control board side. However, the pin connector is provided on the module side and the microcomputer control board side is provided. A similar effect can be obtained even if a connection terminal is provided in the case.
[0078]
As described above, according to the present embodiment, at least the module case is provided with a support mechanism for fixing the substrate, so that restrictions on the module arrangement are alleviated, and the direction of the module connection terminals can be freely arranged.
[0079]
Further, the control signal connection terminal 17b of the module is connected by the pin connector 24 of the microcomputer control board 12b and can be easily fixed without being fixed by soldering. Of course, instead of using the pin connector 24, a hole may be provided in the microcomputer control board and soldered for connection. In this case, however, the signal connection terminal 17b itself of the module does not have to be so strong as in the above-described conventional example, and the direction and the arrangement can be freely arranged, which has a great advantage over the conventional example.
[0080]
On the other hand, in terms of product maintenance services, the soldering part is heated and melted as before, and the control board connected to the module is removed while the solder is melted. It is no longer necessary to perform work, and each component can be separated by simply removing the module screws 25 that are fixed to the heat radiation fins without removing the control board from the module. become able to.
[0081]
In addition, as shown in Document 3, there is no need for a double structure or a complicated support structure design equivalent to the mounting structure that also supports the heat radiation fins with the support of the control board, and the cost is reduced. There is also an effect that it can be reduced. Further, in Document 3, since the module and the radiation fin are arranged on the same surface as the component surface of the control board, the module mounting height adjustment, the electronic component arrangement adjustment on the control board, and the heat radiation are performed so as not to contact other electronic components. Although the fin shape must be changed, according to the present embodiment, the module substrate and the microcomputer control substrate 12b are independent, so that a degree of freedom in design can be ensured.
[0082]
In addition, in any of the mounting structures shown in Document 1 and Document 3 shown in FIG. 8, the control board is arranged above or below the module, so that electric noise generated by the switching operation of the module is controlled. It is necessary to improve the noise resistance of the control board so as not to cause malfunction in the circuit. On the other hand, according to the present embodiment, it is possible to reduce noise countermeasures in which both substrates are independent.
[0083]
As described above, in the conventional system, it is necessary to separately provide a dedicated support bracket for supporting the module and the radiation fin in some form or a mechanism equivalent thereto.
[0084]
For this reason, parallel production by partial assembly cannot be performed, and depending on the mounting method, two-surface soldering is required, which complicates the soldering process, resulting in poor workability and increased costs.
[0085]
Therefore, it is a big challenge for designers to secure the product reliability against the stress of the module connection terminal and control board and the noise resistance, and to realize the cost for mounting the module at a low cost. An effective way to satisfy this has not yet been established.
[0086]
On the other hand, in this embodiment, the module substrate 12a and the microcomputer control substrate 12b can be produced on separate lines, and there is an effect that they can be easily combined.
[0087]
As described above in detail, according to the present embodiment, the inverter circuit is mounted on a single substrate, or further mounted on a single substrate including the rectifier circuit portion, and is incorporated in the module case. By making it modular, the inverter circuit unit can be made independent of the main control board.
[0088]
And since the connection between the module and the microcomputer control board that incorporates the microcomputer control circuit on one board can be mechanically combined without soldering, the assembly work between the boards can be done with hand tools, etc. You can do it easily with simple tools.
[0089]
Accordingly, inspection in maintenance service is facilitated, and workability such as time required for disassembly and assembly and replacement of parts can be improved.
[0090]
In addition, since no support brackets are required to support the module, the number of parts is reduced and productivity is improved. In addition, the inverter circuit section once assembled in the board production process is also incorporated into the main board once. Since the process can be omitted and the inverter board part and the other board part can be produced in parallel, productivity can be improved also in the production of the board.
[0091]
In addition, the main circuit board can be separated from the main circuit board that incorporates an electronic circuit that operates at a low voltage and an inverter circuit part that is likely to generate noise due to high voltage and high current. Therefore, the reliability of operation of equipment parts is improved.
[0092]
Overall, it is possible to connect to the substrate at low cost while maintaining high reliability, to reduce unnecessary space for connecting the substrate, so-called dead space, and to perform module design freely.
[0093]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a mounting structure for a power conversion device that improves the adhesion between the power module and the heat sink without increasing the accuracy and assembling accuracy of various components and does not apply unnecessary stress to the components. it can.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of compressor rotation speed control.
FIG. 2 shows an example of substrate division according to the present invention.
FIG. 3 shows an example of substrate division according to the present invention.
FIG. 4 shows an example of a combination of a module and a substrate.
FIG. 5 shows another embodiment of a module / board combination.
FIG. 6 shows another embodiment of a module / board combination.
FIG. 7 shows another embodiment of a module / board combination.
FIG. 8 shows an example of a conventional module / substrate combination.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Smoothing circuit, 2 ... Rectifier circuit, 3 ... Inverter circuit, 4 ... Microcomputer and compressor motor drive control circuit (microcomputer control circuit), 5 ... Commercial AC power supply, 6 ... Noise filter, 7 ... Power factor improvement circuit, DESCRIPTION OF SYMBOLS 8 ... Module, 9 ... Rotor magnetic pole position detector, 10 ... Compressor motor (stator), 11 ... Main board, 12a ... Module board (aluminum board), 12b ... Microcomputer control board, 13 ... Power supply input circuit board (module, Circuits other than microcomputer control board), 14 ... module case 14a ... board fixing mechanism, 15 ... microcomputer board case, 16 ... semiconductor element (heat generating semiconductor element), 17a ... module connection terminal (large terminal), 17b ... module connection terminal ( Control signal terminals), 18 ... Module cooling fins, 19 ... Compressor connection cable, 20 ... Pin connector , 21 ... connection cable, 22a ... board case side fixing mechanism, 22b ... module side fixing mechanism, 23a ... board case side fixing mechanism, 23b ... module side fixing mechanism, 24 ... pin connector, 25 ... module = heat radiation fin fixing screw DESCRIPTION OF SYMBOLS 100 ... Radiation fin for cooling, 102 ... Inverter module, 103 ... Printed wiring board for control, 104 ... Module connection terminal, 106 ... Molded board.

Claims (2)

  An inverter circuit composed of a plurality of semiconductor switching elements is mounted on a board formed of a heat conductor, a resin module case in which the board is incorporated, and the inverter circuit provided in the module case electrically with the inverter circuit A control circuit for driving the inverter bridge circuit is mounted and electrically connected to the connected terminals, a heat sink to which the module case is attached so that the heat dissipation surface of the substrate is flush with the plane. A control board having a pin connector; and a mechanism provided in the module case for fixing the control board. The inverter circuit and the control circuit are electrically connected by connecting the terminal and the pin connector. The power converter which was made to be connected to.   An inverter circuit composed of a plurality of semiconductor switching elements is mounted on a board formed of a heat conductor, a resin module case in which the board is incorporated, and the inverter circuit provided in the module case electrically with the inverter circuit A connected pin connector, a heat sink to which the module case is attached so that the heat radiating surface of the board is flush with the plane, and a control circuit for driving the inverter bridge circuit are mounted and electrically connected to the control circuit. A control board having a terminal and a mechanism provided on the module case for fixing the control board, and the inverter circuit and the control circuit are electrically connected by coupling the pin connector and the terminal. The power converter which was made to be connected to.

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