JP2010213478A - Power converter and fuel cell system using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power converter having a structure of a small voltage stepup converter totally satisfying the limitations of complicated arrangement or wiring. <P>SOLUTION: The power converter has at least a voltage stepup converter for stepping up a DC voltage, and an inverter circuit for receiving the input step-up voltage and shaping the waveform of an output current into a sinusoidal wave. The voltage stepup converter includes a high-frequency voltage stepup transformer 37 for stepping up the DC voltage, and a circuit board 20 having the high-frequency voltage stepup transformer 37 arranged therein, wherein a leadout line 37A of a pair of primary windings of the high-frequency voltage stepup transformer 37 is connected to the circuit board 20 spaced from the position where the high-frequency voltage stepup transformer 37 is arranged, and a leadout line 37B of a pair of secondary windings of the high-frequency voltage stepup transformer 37 is connected to a circuit board 20 near the position where the high-frequency voltage stepup transformer 37 is arranged. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power conversion device that converts direct current power into alternating current power at a commercial frequency and injects power into the system, and a fuel cell system using the power conversion device.

  A conventional power conversion device will be described with reference to the drawings. FIG. 7 is a block diagram showing an example of the configuration of a conventional power converter.

  As shown in FIG. 7, the power conversion device inputs DC power from, for example, the fuel cell 51, converts the DC power into 50 Hz or 60 Hz AC, and supplies AC power to the system 52.

  The power converter includes a boost converter 53 that boosts the input voltage Vin, an intermediate capacitor 54 that removes a high-frequency component of the boosted voltage, an inverter circuit 55 that shapes the output current into a sine wave, and an inverter circuit And a filter 56 for removing high-frequency noise from the output of 55 and connected to the system 52.

  At this time, the boost converter 53 has a smoothing capacitor 531 for smoothing the input voltage, a full bridge converter circuit 532 using four switching elements Q533 to Q536, and a terminal block whose primary side is connected to the output of the converter circuit 532. And a rectifier circuit 538 connected to the secondary side of the high-frequency boost transformer 537 with a terminal block. Further, inverter circuit 55 has a full bridge configuration using four stones of power switching elements Q539 to Q542.

  Normally, in the case of a fuel cell that is a power supply source, the input voltage to the power conversion device is relatively low. Therefore, it is common to use a power conversion device including a boost converter 53 that converts an input voltage into a high voltage.

  However, when a high step-up ratio is realized by a single-stage booster circuit and a single high-frequency boost transformer in a conventional power converter, there is a large difference in the wire diameter and the number of turns between the primary and secondary windings of the high-frequency boost transformer. Is required. Therefore, it is difficult to configure a high-frequency step-up transformer with a high degree of coupling.

Thus, a configuration is disclosed in which a high-frequency step-up transformer with a large terminal block is installed separately from a printed circuit board on which electronic components are mounted (see, for example, Patent Document 1). That is, in the power conversion device of Patent Document 1, in order to flow a large current to the primary side of the high-frequency boost transformer used in the boost converter, the high-frequency boost transformer with a terminal block is separated from the circuit board on which electronic components are mounted. It is installed in the power converter. And it is the structure which connects the terminal block of a high frequency step-up transformer, and a circuit board using a connecting wire.
JP 61-236373 A

  However, in the conventional configuration, since the high-frequency step-up transformer is separately installed, it is difficult to reduce the size of the power converter.

  In addition, if the length of the connecting wire connecting the terminal block of the high-frequency step-up transformer and the copper foil pattern on the circuit board is increased, the effect of suppressing the surge voltage of the capacitor is hindered by wiring impedance, etc., and an excessive load is applied to the switching element. There was a problem.

  Further, in the arrangement and wiring of the components constituting the boost converter, there is a problem that power cannot be supplied uniformly to the booster circuit due to the imbalance in the length of the wiring between the components.

  The present invention solves the above-described conventional problems, and provides a power conversion device having a small boost converter configuration that comprehensively satisfies constraints such as complex arrangement and wiring, and a fuel cell system using the same. With the goal.

  In order to solve the above-described conventional problems, a power converter of the present invention includes at least a boost converter that boosts a DC voltage, and an inverter circuit that inputs the boosted DC voltage and shapes an output current into a sine wave. The boost converter includes a high-frequency boost transformer that boosts a DC voltage, and a circuit board on which the high-frequency boost transformer is arranged, and a pair of primary winding lead wires of the high-frequency boost transformer are connected to the high-frequency boost transformer. Is connected to a circuit board away from the position where the high-frequency step-up transformer is disposed, and the lead wires of the pair of secondary windings of the high-frequency step-up transformer are connected to the circuit board near the position where the high-frequency step-up transformer is disposed.

  With this configuration, the power conversion device can be reduced in size. In addition, the surge voltage due to the wiring impedance can be suppressed, and the switching loss when the power switching element of the boost converter is switched can be reduced. As a result, it is possible to realize a small-sized power conversion device with high conversion efficiency and excellent energy saving.

  The fuel cell system according to the present invention includes at least the power conversion device and a fuel cell that generates a DC voltage from a fuel gas mainly composed of hydrogen and oxygen, and is a boost converter of the power conversion device. It has a configuration for boosting the generated DC voltage. Thereby, the fuel cell system excellent in power generation efficiency is realizable.

  The power conversion device of the present invention is small in size by optimizing the arrangement of the lead lines of the high-frequency step-up transformer, and high reliability and conversion efficiency can be obtained.

  Moreover, the fuel cell system of this invention can improve power generation efficiency with the power converter device with high conversion efficiency.

  A first invention is a power converter including at least a boost converter that boosts a DC voltage and an inverter circuit that inputs a boosted DC voltage and shapes an output current into a sine wave. The boost converter includes: A high-frequency boost transformer that boosts the DC voltage and a circuit board on which the high-frequency boost transformer is placed are connected, and the lead wires of the pair of primary windings of the high-frequency boost transformer are connected to a circuit board that is remote from the position where the high-frequency boost transformer is placed. Then, the power conversion device has a configuration in which the lead wires of the pair of secondary windings of the high-frequency boost transformer are connected to a circuit board in the vicinity of the position where the high-frequency boost transformer is disposed.

  With this configuration, the power conversion device can be reduced in size. In addition, the surge voltage due to the wiring impedance can be suppressed, and the switching loss when the power switching element of the boost converter is switched can be reduced. As a result, it is possible to realize a small-sized power conversion device with high conversion efficiency and excellent energy saving.

  A second invention is the power converter according to the first invention, wherein the lead wires of the pair of primary windings of the high-frequency step-up transformer are drawn in substantially the same direction. Thereby, electric power can be supplied uniformly.

  A third invention is the power conversion device according to the first or second invention, wherein the lead wires of the pair of primary windings of the high-frequency step-up transformer are formed of lead wires, conductor plates or pins. Thereby, the connection reliability and mountability of the high-frequency step-up transformer can be improved.

  A fourth invention is the power conversion device according to any one of the first to third inventions, wherein the lead wires of the pair of secondary windings of the high frequency step-up transformer are a lead wire, a conductor plate or a pin. Thereby, the connection reliability and mountability of the high-frequency step-up transformer can be improved.

  A fifth invention is the power conversion device according to any one of the first to fourth inventions, wherein the lead wires of the pair of secondary windings of the high-frequency step-up transformer are connected to the circuit board by surface mounting. As a result, the high-frequency step-up transformer can be reliably mounted on the circuit board, and a highly reliable power conversion device can be realized.

  In a sixth aspect based on the first aspect, the step-up converter includes a plurality of high-frequency step-up transformers, and the lead-out directions of the lead lines of the primary windings of the plurality of high-frequency step-up transformers are drawn in directions opposite to each other. It is the power converter device connected to. Thereby, the imbalance of the length of the wiring can be improved and the power can be supplied uniformly.

  A seventh invention is the power conversion device according to any one of the first to sixth inventions, wherein the lead-out positions of the lead wires of the pair of primary windings of the high-frequency step-up transformer are arranged apart vertically. Thereby, the mounting property of the high frequency step-up transformer can be improved and the mounting area can be reduced.

  According to an eighth invention, in any one of the first to seventh inventions, the boost converter includes a first circuit board on which the high-frequency boost transformer is arranged and a second circuit board, and a pair of primary of the high-frequency boost transformer. The power conversion device connects a lead wire of a winding to a second circuit board and connects a lead wire of a pair of secondary windings of the high-frequency step-up transformer to the first circuit board. As a result, it is possible to improve versatility such as circuit board area and circuit board pattern design in accordance with the magnitude of the current flowing through the high-frequency step-up transformer.

  A ninth invention is the power conversion device according to the eighth invention, wherein the lead wires of the pair of secondary windings of the high-frequency step-up transformer are connected to the first circuit board by surface mounting. As a result, the high-frequency step-up transformer can be reliably mounted on the circuit board, and a highly reliable power conversion device can be realized.

  According to the invention of the younger brother 10, in the eighth or ninth invention, the boost converter includes a plurality of high-frequency boost transformers, and the lead-out directions of the lead wires of the primary windings of the plurality of high-frequency boost transformers are drawn in directions opposite to each other. The power conversion device connected to the second circuit board. Thereby, the imbalance of the length of the wiring can be improved and the power can be supplied uniformly.

  An eleventh aspect of the invention includes at least a power converter according to any one of the first to tenth aspects and a fuel cell that generates a DC voltage from a fuel gas mainly composed of hydrogen and oxygen. This is a fuel cell system that boosts a DC voltage generated by a fuel cell using a boost converter. Thereby, the fuel cell system excellent in power generation efficiency is realizable.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same reference numerals are given to the same configurations as those of the conventional examples or the embodiments described above, and detailed description thereof will be omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
Below, the power converter device in Embodiment 1 of this invention is demonstrated using drawing.

  FIG. 1 is a circuit block diagram of a power conversion device for a fuel cell according to Embodiment 1 of the present invention. 2A is a plan view of the boost converter of the power conversion device according to the first embodiment of the present invention, and FIG. 2B is a plan view of the boost converter of the power conversion device according to the first embodiment of the present invention. It is a side view which shows another example. In the following, a fuel cell system in which a fuel cell is connected to the power conversion device of the present embodiment will be described as an example.

  That is, as shown in FIG. 1, the power conversion device of the present embodiment receives DC power from a fuel cell 1 that generates DC voltage from a fuel gas mainly composed of hydrogen and oxygen, and the input DC power. Is converted into AC of 50 Hz or 60 Hz and AC power is supplied to the system 2.

  The power converter then boosts the input voltage Vin generated by the fuel cell 1, the intermediate capacitor 4 that removes the high frequency component of the boosted voltage, and shapes the output current into a sine wave. The inverter circuit 5 and a filter 6 that removes high-frequency noise from the output of the inverter circuit 5 are provided at least, and are connected to the system 2.

  Here, the boost converter 3 has a smoothing capacitor 31 for smoothing the input voltage, a full bridge converter circuit 32 using four stones of power switching elements Q33 to Q36, and a primary side connected to the output of the converter circuit 32. A high-frequency step-up transformer 37 and a rectifier circuit 38 connected to the secondary side of the high-frequency step-up transformer 37 are configured. Further, the inverter circuit 5 is configured in a full bridge configuration using four switching elements Q39 to Q42.

  At this time, the power switching elements Q33 to Q36 of the converter circuit 32 and the inverter circuit 5 are composed of, for example, SiC, GaN, SiGe, MOSFET, IGBT, or transistor. The diode of the rectifier circuit 38 is composed of SiC, GaN, SiGe, or the like.

  As shown in FIG. 2, a pair of high-frequency step-up transformers 37 mounted on the circuit board 20 of the boost converter 3, for example, lead wires 37A of primary windings made of lead wires are substantially in the same direction and substantially on the same plane. And is connected to the position of the circuit board 20 away from the position where the high-frequency step-up transformer 37 is disposed, for example, by soldering. The lead wires 37B of the pair of secondary windings of the high-frequency boost transformer 37 are mounted by being inserted, for example, via pins into the position of the circuit board 20 near the position where the high-frequency boost transformer 37 is disposed. It is connected to a wiring pattern (not shown) of the substrate 20.

  In the above description, the lead wire 37A of the primary winding of the high frequency step-up transformer 37 is described as an example of the lead wire. However, the present invention is not limited to this, and the lead wire 37A may be drawn by a conductor plate or a pin. Similarly, the lead wire 37B of the secondary winding of the high-frequency step-up transformer 37 may be drawn by a lead wire or a conductor plate. Thereby, handleability and mountability can be improved.

  In the above description, the example in which the lead wires 37B of the pair of secondary windings of the high-frequency step-up transformer 37 are connected by soldering has been described. However, the present invention is not limited to this. Thereby, a connection can be simplified.

  In the above description, the example in which the lead wires 37A of the pair of primary windings of the high-frequency step-up transformer 37 are drawn on substantially the same plane has been described. However, the present invention is not limited to this. For example, as shown in FIG. 2B, the lead wires 37 </ b> A of the pair of primary windings of the high-frequency boost transformer 37 may be drawn from positions that are separated vertically in the height direction of the high-frequency boost transformer 37. Thereby, handling of a lead wire can be made easy and productivity can be improved.

  In the above description, the converter circuit 32 has been described by taking a full bridge configuration as an example, but the present invention is not limited to this. For example, a half bridge converter circuit or a push-pull converter circuit may be used, and the same operation can be realized.

  According to the power conversion device of the present embodiment, since it is not necessary to have on the circuit board 20 a terminal block for connecting a pair of secondary windings of a high-frequency step-up transformer with a large terminal block, a circuit through which a large current flows The area of the substrate 20 can be reduced.

  Further, since the lead wires 37B of the pair of secondary windings of the high-frequency boost transformer 37 are configured by soldering or surface mounting, the high-frequency boost transformer 37 is higher than the current one using a high-frequency boost transformer with a large terminal block. Since it becomes small, a power converter device can be reduced in size.

  In addition, according to the present embodiment, since the lead wires 37B of the pair of secondary windings of the high frequency boost transformer 37 are configured by pins, conductor plates, lead wires, or surface mounting, the high frequency boost transformer 37 is provided on the circuit board 20. Because it is easy to mount, soldering can be done reliably. Thereby, the power converter device excellent in the reliability of connection is obtained.

  Further, according to the present embodiment, the lead wire 37A on the primary winding side of the high-frequency step-up transformer 37 can be arranged as short as possible without causing an imbalance. Therefore, the wiring impedance can be reduced and the surge voltage can be suppressed. As a result, the switching loss at the time of switching of the power switching elements Q33 to Q36 of the boost converter 3 can be reduced, and an energy saving and highly efficient power conversion device can be realized.

  Moreover, a fuel cell system with high power generation efficiency can be realized by connecting the fuel cell and the power conversion device.

(Embodiment 2)
Below, the power converter device in Embodiment 2 of this invention is demonstrated using drawing.

  FIG. 3 is a circuit block diagram of a power conversion device for a fuel cell according to Embodiment 2 of the present invention. FIG. 4A is a plan view of the boost converter of the power conversion device according to the second embodiment of the present invention, and FIG. 4B is the boost converter of the power conversion device according to the second embodiment of the present invention. It is a side view which shows another example.

  That is, as shown in FIGS. 3 and 4, the power conversion device according to the present embodiment is implemented in that the boost converter 15 includes at least two first boost converter units and second boost converter units. This is different from the first form.

  As shown in FIG. 4 (a), the power conversion device according to the present embodiment draws out the lead wires of the primary windings of the two high-frequency boost transformers constituting the first boost converter unit and the second boost converter unit. The directions are arranged on the circuit board so as to face each other.

  Hereinafter, boost converter 15 of the power conversion device of the present embodiment will be specifically described. Except for step-up converter 15, the description is omitted because it is the same as in the first embodiment.

  As shown in FIG. 3, the boost converter 3 according to the first embodiment is a first boost converter unit 3 and a second boost converter unit 10 is connected to each other to form a boost converter 15.

  At this time, the first step-up converter unit 3 includes a smoothing capacitor 31 that smoothes the input voltage, a full-bridge converter circuit 32 that uses four power switching elements Q33 to Q36, and an output of the converter circuit 32 that has a primary side. The high-frequency step-up transformer 37 is connected, and the rectifier circuit 38 is connected to the secondary side of the high-frequency step-up transformer 37.

  Similarly, the second boost converter unit 10 includes a smoothing capacitor 11 for smoothing the input voltage, a converter circuit 12 having a full bridge configuration using four stones of power switching elements Q13 to Q16, and a primary side on the output of the converter circuit 12. The high-frequency step-up transformer 17 is connected, and the rectifier circuit 18 is connected to the secondary side of the high-frequency step-up transformer 17.

  The converter circuit 32 of the first boost converter unit 3 and the converter circuit 12 of the second boost converter unit 10 are connected in parallel with the fuel cell 1, and the rectifier circuit 38 of the first boost converter unit 3 and the second boost converter unit. The outputs of the ten rectifier circuits 18 are connected in series. Thereby, a high DC voltage can be obtained.

  At this time, as shown in FIG. 4A, a pair of high-frequency step-up transformers 37 mounted on the circuit board 21 of the first step-up converter unit 3, for example, lead wires 37A of primary windings made of lead wires are substantially It is pulled out on substantially the same plane in the same direction, and connected to the position of the circuit board 21 away from the position where the high-frequency step-up transformer 37 is disposed, for example, by soldering. The lead wires 37B of the pair of secondary windings of the high-frequency boost transformer 37 are mounted by being inserted, for example, via pins into the position of the circuit board 21 near the position where the high-frequency boost transformer 37 is disposed. It is connected to a wiring pattern (not shown) of the substrate 20.

  Similarly, a pair of high-frequency step-up transformers 17 mounted on the circuit board 21 of the second step-up converter unit 10, for example, lead wires 17 </ b> A of primary windings made of lead wires are led out on substantially the same plane in substantially the same direction. Then, it is connected to the position of the circuit board 21 away from the position where the high-frequency step-up transformer 17 is disposed, for example, by soldering. Further, the lead wires 17B of the pair of secondary windings of the high frequency boost transformer 17 are mounted by being inserted, for example, via pins into the position of the circuit board 21 near the position where the high frequency boost transformer 17 is disposed. A wiring pattern (not shown) of the substrate 21 is connected.

  At this time, as shown in FIG. 4A, the lead-out direction of the lead wire 37 </ b> A of the pair of primary windings of the high-frequency boost transformer 37 of the first boost converter unit 3 is the high-frequency boost transformer 17 of the second boost converter unit 10. The lead wires 17A of the pair of primary windings are arranged and mounted on the circuit board in the direction opposite to each other and the direction in which they are opposed to each other.

  According to the power conversion device of the present embodiment, the use of a plurality of high-frequency boost transformers 17 and 37 makes the high-frequency boost transformers 17 and 37 smaller than the case of a single high-frequency boost transformer, and the primary winding. The degree of coupling between the line and the secondary winding is increased, and the loss of the high-frequency step-up transformers 17 and 37 can be reduced.

  In addition, according to the power conversion device of the present embodiment, it is not necessary to have on the circuit board 21 a terminal block for connecting a pair of secondary windings of a high-frequency step-up transformer with a large terminal block. The area of the flowing circuit board 21 can be reduced. Further, since the lead wires 17B and 37B of the pair of secondary windings of the high-frequency step-up transformers 17 and 37 are configured by soldering or surface mounting, the frequency is higher than that of the current one using a high-frequency step-up transformer with a large terminal block. Since the step-up transformers 17 and 37 are downsized, the power converter can be downsized.

  In addition, according to the present embodiment, since the lead wires 17B and 37B of the pair of secondary windings of the high frequency boost transformers 17 and 37 are configured by pins, conductor plates, lead wires, or surface mounting, the high frequency boost transformer 17 , 37 can be easily mounted on the circuit board 21, so that soldering can be ensured. Thereby, the power converter device excellent in the reliability of connection is obtained.

  Further, according to the present embodiment, the lead wires 17A and 37A of the primary windings of the high-frequency step-up transformers 17 and 37 can be arranged as short as possible without causing an imbalance. Therefore, the wiring impedance can be reduced and the surge voltage can be suppressed. As a result, the switching loss at the time of switching of the power switching elements Q33 to Q36 of the boost converter 3 can be reduced, and an energy saving and highly efficient power conversion device can be realized.

  Moreover, a fuel cell system with high power generation efficiency can be realized by connecting the fuel cell and the power conversion device.

(Embodiment 3)
Below, the power converter device in Embodiment 3 of this invention is demonstrated using FIG. The circuit block diagram of the fuel cell power conversion device of the third embodiment is the same as that of FIG. 1 of the first embodiment, and will be described with reference to FIG.

  FIG. 5A is a plan view of the boost converter of the power conversion device according to the third embodiment of the present invention, and FIG. 5B is another diagram of the boost converter of the power conversion device according to the third embodiment of the present invention. It is a side view which shows an example.

  That is, as shown in FIG. 5, in the power conversion device of the present embodiment, the circuit board on which the boost converter 3 is arranged is composed of a plurality of circuit boards 22 and 23, and the high-frequency boost transformer 37 is arranged. The first circuit board 22 is different from the first embodiment in that the second circuit board 23 to which the lead wire 37A of the primary winding of the high frequency step-up transformer 37 is connected is different. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  That is, as shown in FIG. 5, the boost converter 3 is provided with a high-frequency boost transformer 37 that boosts the generated DC voltage, a first circuit board 22 on which the high-frequency boost transformer 37 is disposed, and a high-frequency boost transformer 37. The second circuit board 23 is not provided. A pair of primary winding lead lines 37A of the high frequency boost transformer 37 are connected to the second circuit board 23, and a pair of secondary winding lead lines 37B of the high frequency boost transformer 37 are arranged by the high frequency boost transformer 37. It is connected to the first circuit board 22 in the vicinity of the position.

  According to the power conversion device of the present embodiment, a small current flows through the first circuit board 22 on which the high frequency boost transformer 37 is arranged, and the second lead wire 37A of the primary winding of the high frequency boost transformer 37 is connected. Since a large current flows through the circuit board 23, the conductor pattern thickness of each circuit board 22, 23 can be made different, so that the cost reduction of the circuit boards 22, 23 can be realized.

  In addition, according to the power conversion device of the present embodiment, it is not necessary to have on the circuit board a terminal block for connecting a pair of secondary windings of a high-frequency step-up transformer with a large terminal block. 23 area can be reduced. Further, since the lead wires 37B of the pair of secondary windings of the high-frequency boost transformer 37 are configured by soldering or surface mounting, the high-frequency boost transformer 37 is higher than the current one using a high-frequency boost transformer with a large terminal block. Since it becomes small, a power converter device can be reduced in size.

  Further, according to the present embodiment, since the lead wires 37B of the pair of secondary windings of the high frequency boost transformer 37 are configured by pins, conductor plates, lead wires, or surface mounting, the high frequency boost transformer 37 is provided on the circuit board 22. Because it is easy to mount, soldering can be done reliably. Thereby, the power converter device excellent in the reliability of connection is obtained.

  In addition, according to the present embodiment, the lead wire 37A of the primary winding of the high-frequency step-up transformer 37 can be arranged as short as possible without causing an imbalance. Therefore, the wiring impedance can be reduced and the surge voltage can be suppressed. As a result, the switching loss at the time of switching of the power switching elements Q33 to Q36 of the boost converter 3 can be reduced, and an energy saving and highly efficient power conversion device can be realized.

  Moreover, a fuel cell system with high power generation efficiency can be realized by connecting the fuel cell and the power conversion device.

(Embodiment 4)
Below, the power converter device in Embodiment 4 of this invention is demonstrated using FIG. The circuit block diagram of the power conversion device for the fuel cell according to the fourth embodiment is the same as that of FIG.

  FIG. 6A is a plan view of the boost converter of the power conversion device according to the fourth embodiment of the present invention, and FIG. 6B is another diagram of the boost converter of the power conversion device according to the fourth embodiment of the present invention. It is a side view which shows an example.

  That is, as shown in FIG. 6, in the power conversion device of the present embodiment, the circuit board on which the boost converter is arranged is composed of a plurality of circuit boards, and the circuit board on which the high-frequency boost transformer is arranged, and the high-frequency boost The second embodiment is different from the second embodiment in that the circuit board to which the lead wire of the primary winding of the transformer is connected is different. Since other configurations are the same as those of the second embodiment, description thereof is omitted.

  That is, as shown in FIG. 6, the first boost converter unit 3 and the second boost converter unit 10 include the first circuit board 24 on which the high frequency boost transformers 17 and 37 are disposed and the high frequency boost transformers 17 and 37. The second circuit board 25 is provided. The pair of primary winding lead lines 17A and 37A of the high frequency boost transformers 17 and 37 are connected to the second circuit board 25, and the pair of secondary winding lead lines 17B and 37B of the high frequency boost transformers 17 and 37 are connected. Are inserted into and connected to the first circuit board 24 in the vicinity of the position where the high-frequency step-up transformers 17 and 37 are disposed.

  According to the power conversion device of the present embodiment, the use of a plurality of high-frequency boost transformers 17 and 37 makes the high-frequency boost transformers 17 and 37 smaller than the case of a single high-frequency boost transformer. The degree of coupling between the winding and the secondary winding is increased, and the loss of the high-frequency step-up transformers 17 and 37 can be reduced.

  Further, a small current flows through the first circuit board 24 on which the high frequency boost transformers 17 and 37 are arranged, and the second circuit board 25 to which the lead wires 17A and 37A of the primary windings of the high frequency boost transformers 17 and 37 are connected. Since a large current flows, the conductor pattern thickness of each circuit board 24, 25 can be made different, so that the cost reduction of the circuit boards 24, 25 can be realized.

  Further, according to the power conversion device of the present embodiment, it is not necessary to have on the circuit board a terminal block for connecting a pair of secondary windings of a high-frequency step-up transformer with a large terminal block. , 25 can be reduced.

  Further, since the lead wires 17B and 37B of the pair of secondary windings of the high-frequency step-up transformers 17 and 37 are configured by soldering or surface mounting, the frequency is higher than that of the current one using a high-frequency step-up transformer with a large terminal block. Since the step-up transformers 17 and 37 are reduced in size, the power converter can be reduced in size.

  In addition, according to the present embodiment, since the lead wires 17B and 37B of the pair of secondary windings of the high frequency boost transformers 17 and 37 are configured by pins, conductor plates, lead wires, or surface mounting, the high frequency boost transformer 17 37 can be easily mounted on the first circuit board 24, so that soldering can be ensured. Thereby, the power converter device excellent in the reliability of connection is obtained.

  Further, according to the present embodiment, the lead wires 17A and 37A of the primary windings of the high-frequency step-up transformers 17 and 37 can be arranged as short as possible without causing an imbalance. Therefore, the wiring impedance can be reduced and the surge voltage can be suppressed. As a result, it is possible to reduce the switching loss at the time of switching of the power switching element of the boost converter, and to realize an energy saving and highly efficient power conversion device.

  Moreover, a fuel cell system with high power generation efficiency can be realized by connecting the fuel cell and the power conversion device.

  The power conversion device according to the present invention is useful in technical fields such as a fuel cell device, a solar power generation device, a wind power generation device, and a solar power generation device that require space saving and energy saving by a small and highly efficient boost converter. is there.

1 is a circuit block diagram of a power conversion device for a fuel cell according to Embodiment 1 of the present invention. (A) Plan view of the boost converter of the power conversion device in the first embodiment of the present invention (b) Side view showing another example of the boost converter of the power conversion device in the same embodiment Circuit block diagram of a power conversion device for a fuel cell in Embodiment 2 of the present invention (A) Plan view of the boost converter of the power conversion device in Embodiment 2 of the present invention (b) Side view showing another example of the boost converter of the power conversion device in the same embodiment (A) Plan view of the boost converter of the power conversion device according to the third embodiment of the present invention (b) Side view showing another example of the boost converter of the power conversion device according to the same embodiment (A) Plan view of the boost converter of the power conversion device in the fourth embodiment of the present invention (b) Side view showing another example of the boost converter of the power conversion device in the same embodiment The block diagram which shows an example of a structure of the conventional power converter device

DESCRIPTION OF SYMBOLS 1 Fuel cell 2 systems 3,15 Boost converter (1st boost converter part)
DESCRIPTION OF SYMBOLS 10 2nd step-up converter part 4, 11, 31 Capacitor 5 Inverter circuit 6 Filter 12, 32 Converter circuit 17, 37 High frequency step-up transformer 17A, 37A Primary winding lead line 17B, 37B Secondary winding lead line 18, 38 Rectifier circuit 20, 21 Circuit board 22, 24 First circuit board 23, 25 Second circuit board

Claims (11)

A power converter including at least a boost converter that boosts a DC voltage, and an inverter circuit that shapes the output current into a sine wave using the boosted DC voltage as an input, wherein the boost converter converts the DC voltage A high-frequency boost transformer for boosting and a circuit board on which the high-frequency boost transformer is disposed, and a lead wire of a pair of primary windings of the high-frequency boost transformer is disposed on the circuit board remote from the position where the high-frequency boost transformer is disposed. A power converter for connecting and connecting a lead wire of a pair of secondary windings of the high-frequency boost transformer to the circuit board in the vicinity of a position where the high-frequency boost transformer is disposed. The power conversion device according to claim 1, wherein the lead wires of the pair of primary windings of the high-frequency step-up transformer are drawn in substantially the same direction. The power converter according to claim 1 or 2, wherein the lead wires of the pair of primary windings of the high-frequency step-up transformer are lead wires, conductor plates, or pins. The power converter according to any one of claims 1 to 3, wherein the lead wires of the pair of secondary windings of the high-frequency step-up transformer are lead wires, conductor plates, or pins. 5. The power conversion device according to claim 1, wherein lead wires of the pair of secondary windings of the high-frequency step-up transformer are connected to the circuit board by surface mounting. 6. The step-up converter includes a plurality of the high-frequency step-up transformers, the lead-out directions of the lead wires of the primary windings of the plurality of the high-frequency step-up transformers are led out in directions opposite to each other, and are connected to the circuit board. The power converter according to 1. The power converter according to any one of claims 1 to 6, wherein the lead-out positions of the lead wires of the pair of primary windings of the high-frequency step-up transformer are arranged apart from each other in the vertical direction. The boost converter includes a first circuit board on which the high-frequency boost transformer is disposed, and a second circuit board, and a pair of primary winding lead wires of the high-frequency boost transformer are connected to the second circuit board. The power converter according to any one of claims 1 to 7, wherein lead wires of a pair of secondary windings of the high-frequency step-up transformer are connected to the first circuit board. The power conversion device according to claim 8, wherein lead wires of a pair of secondary windings of the high-frequency step-up transformer are connected to the first circuit board by surface mounting. The step-up converter includes a plurality of the high-frequency step-up transformers, the lead-out directions of the lead wires of the primary windings of the plurality of the high-frequency step-up transformers are drawn out in directions opposite to each other, and are connected to the second circuit board. The power converter according to claim 8 or 9. 11. The power converter according to claim 1 and a fuel cell that generates a DC voltage from a fuel gas mainly composed of hydrogen and oxygen, wherein the boost converter of the power converter is the fuel cell. A fuel cell system that boosts the generated DC voltage.

Images