Power conversion device

Abstract

To provide a power conversion device capable of torque control with high accuracy so that the sum of torque command values input to a plurality of power conversion units and an input torque command value for an entire system including the plurality of power conversion units are equal even when divided input torque command values for the plurality of power conversion units are corrected so that DC input voltages of the plurality of power conversion units are equal.SOLUTION: A power conversion device 1 has an input voltage adjusting unit 50 for correcting divided input torque command values input to each of a plurality of power conversion units 10, 20, 30 in accordance with an input torque command value Trq_ref so that a voltage on the input side of the plurality of power conversion portions 10, 20, 30 is made equal and a torque command adjusting unit 60 for correcting the divided input torque command values using second torque command correction values obtained by dividing the sum of correction values of the divided input torque command values by the input voltage adjusting unit 50 into the plurality of power conversion portions 10, 20, 30.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power conversion device having a plurality of power conversion units whose input sides are electrically connected in series to a power source and which supply electric power to a motor in response to a torque command. [Background technology]

[0002] There is known a power conversion device having a plurality of power conversion units whose input sides are electrically connected in series to a power source and which supply power to a motor in response to a torque command. As an example of such a power conversion device, as disclosed in Patent Document 1, there is known an inverter control device that controls a series multiple inverter system in which the DC sides of a plurality of inverters are connected in series to one DC power source and an AC motor is connected to the AC side of each of the plurality of inverters.

[0003] The above-mentioned Patent Document 1 discloses that the inverter control device controls the d-axis current in accordance with the DC input voltage of each inverter so that the series input voltages of the inverters are equalized. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-104973 A Summary of the Invention [Problem to be solved by the invention]

[0005] The inverter control device disclosed in Patent Document 1 can equalize the DC input voltages of the inverters (power conversion units). In this case, divided input torque command values ​​obtained by dividing the input torque command value among the multiple power conversion units are adjusted so that the DC input voltages are equal to each other.

[0006] However, due to variations in the characteristics of the components in each power conversion unit, variations in the characteristics of the load to which each power conversion unit outputs power, and differences in control response when the DC input voltages of each power conversion unit are made equal, the sum of the correction amounts of the divided input torque command values ​​for the multiple power conversion units is not necessarily zero.

[0007] In this case, when the split input torque command values ​​for the multiple power conversion units are corrected as described above, there is a possibility that the sum of the torque command values ​​input to the multiple power conversion units after the correction of the split input torque command values ​​will not match the input torque command value for the entire system including the multiple power conversion units.

[0008] For this reason, even when the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of each power conversion unit are equal as described above, a configuration is desired that performs accurate torque control so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value for the entire system including the multiple power conversion units.

[0009] An object of the present invention is to provide a power conversion device capable of precise torque control so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value for the entire system including the multiple power conversion units, even when the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of the multiple power conversion units are equivalent. [Means for solving the problem]

[0010] A power conversion device according to an embodiment of the present invention has a plurality of power conversion units whose input sides are electrically connected in series to a power source and which supply power to a load in accordance with an input torque command value, an input voltage adjustment unit that corrects divided input torque command values ​​input to the plurality of power conversion units in accordance with the input torque command value so that voltages on the input sides of the plurality of power conversion units are equal, and a torque command adjustment unit that corrects the divided input torque command value using a torque command correction value obtained by dividing a correction amount of the divided input torque command value by the input voltage adjustment unit among the plurality of power conversion units (first configuration).

[0011] This makes it possible to correct the divided input torque command values ​​for the multiple power conversion units using torque command correction values ​​obtained by dividing the correction amount of the divided input torque command value by the input voltage adjustment unit among the multiple power conversion units. Therefore, even when the divided input torque command values ​​for the multiple power conversion units are corrected so that the voltages on the input sides electrically connected in series to a power source in the multiple power conversion units are equal, the divided input torque command values ​​can be corrected by the torque command adjustment unit so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value.

[0012] Therefore, even if the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of the multiple power conversion units are equivalent, a power conversion device capable of precise torque control can be provided so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value.

[0013] In the first configuration, the plurality of power conversion units supply power to one load (second configuration).

[0014] In this way, when a plurality of power conversion units supply power to a single load, in order to control the output torque of the load with high precision, it is necessary to control the power supplied from each of the plurality of power conversion units to the load with high precision in accordance with an input torque command value for the load. Therefore, by using the above-described first configuration, the sum of the torque command values ​​input to the plurality of power conversion units can be made to match the input torque command value, and the output torque of the load can be controlled with high precision.

[0015] In the first or second configuration, the torque command adjustment unit obtains the torque command correction value by equally dividing the total of the correction amounts by the number of the multiple power conversion units, and corrects each of the torque command values ​​using the torque command correction value (third configuration).

[0016] This makes it possible to make the correction amounts equal when correcting the divided input torque command values ​​for multiple power conversion units using torque command correction values ​​obtained by dividing the correction amount of the divided input torque command value by the input voltage adjustment unit among the multiple power conversion units.

[0017] If the correction amount varies for each power conversion unit, this may affect the control for correcting the divided input torque command value so that the input voltages of the multiple power conversion units are equalized. In contrast, by making the correction amount equal for the multiple power conversion units as described above, it is possible to perform accurate and stable torque control.

[0018] Therefore, even if the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of the multiple power conversion units are equivalent, a power conversion device can be provided that can perform accurate and stable torque control so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value.

[0019] In the first or second configuration, the torque command adjustment unit calculates the torque command correction value as the ratio of the value obtained by subtracting the sum of the correction amounts from the input torque command value to the input torque command value, and corrects the divided input torque command values ​​by multiplying each of the torque command values ​​by the torque command correction value (fourth configuration).

[0020] As a result, when the split input torque command values ​​for the multiple power conversion units are corrected in accordance with the sum of the correction amounts of the split input torque command values ​​by the input voltage adjustment unit, the split input torque command values ​​for the multiple power conversion units can be corrected at the same ratio using the ratio between the value obtained by subtracting the sum of the correction amounts from the input torque command value and the input torque command value.

[0021] Therefore, even if the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of the multiple power conversion units are equivalent, a power conversion device can be provided that can perform accurate and stable torque control so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value. Effect of the Invention

[0022] A power conversion device according to one embodiment of the present invention has an input voltage adjustment unit that corrects divided input torque command values ​​for a plurality of power conversion units so that input side voltages of the plurality of power conversion units are equivalent, and a torque command adjustment unit that corrects the divided input torque command value using a torque command correction value obtained by dividing the total correction amount of the divided input torque command value by the input voltage adjustment unit among the plurality of power conversion units.

[0023] This makes it possible to provide a power conversion device that can precisely control torque so that the sum of the torque command values ​​input to the multiple power conversion units matches the input torque command value, even when the divided input torque command values ​​for the multiple power conversion units are corrected so that the DC input voltages of the multiple power conversion units are equivalent. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a power conversion device according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram for explaining generation of a torque command value by the control unit. [Diagram 3] FIG. 3 is a block diagram for explaining generation of a torque command value by a control unit of a power conversion device according to the second embodiment. [Figure 4] FIG. 4 is a block diagram showing a schematic configuration of the torque correction unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters and the description thereof will not be repeated.

[0026] <Embodiment 1> 1 is a diagram showing a schematic configuration of a power conversion device 1 according to a first embodiment of the present invention. The power conversion device 1 has a plurality of power conversion units 10, 20, and 30 electrically connected in series to a DC power supply 3 (power supply). In the power conversion device 1 of this embodiment, the plurality of power conversion units 10, 20, and 30 supply power to one motor 2 (load).

[0027] The motor 2 has multiple phase stator coils 21, 22, 23. In this embodiment, the motor 2 has three phase stator coils 21, 22, 23. Power is supplied to the stator coils 21, 22, 23 of the motor 2 from multiple power conversion units 10, 20, 30 of the power conversion device 1. The configuration of the motor 2 is the same as that of the conventional motor, so a detailed description of the motor 2 will be omitted.

[0028] The power conversion device 1 includes a plurality of power conversion units 10, 20, and 30, and a control unit .

[0029] The power conversion units 10, 20, 30 have an input side electrically connected in series to a DC power supply 3 (power supply). The power conversion units 10, 20, 30 each have a plurality of switching elements (not shown). A torque command value is input to the power conversion units 10, 20, 30 from a control unit 40. The power conversion units 10, 20, 30 drive the switching elements in accordance with the torque command value to convert the input DC voltage into a predetermined AC voltage and output it to each of the stator coils 21, 22, 23 of the motor 2. The power conversion units 10, 20, 30 have the same configuration as the conventional power conversion units, and therefore a detailed description of the power conversion units 10, 20, 30 will be omitted.

[0030] The control unit 40 generates torque command values ​​Trq1, Trq2, and Trq3 for the multiple power conversion units 10, 20, and 30 based on the input torque command value Trq_ref and outputs them to the multiple power conversion units 10, 20, and 30. The control unit 40 has a torque command generation unit 41 that generates the torque command values ​​Trq1, Trq2, and Trq3 based on the input torque command value Trq_ref.

[0031] The torque command generating unit 41 includes an input voltage adjusting unit 50 and a torque command adjusting unit 60 .

[0032] Fig. 2 is a block diagram for explaining generation of torque command values ​​Trq1, Trq2, and Trq3 by the control unit 40. The configurations and functions of the input voltage adjusting unit 50 and the torque command adjusting unit 60 will be explained using Fig. 2.

[0033] The input voltage adjusting unit 50 corrects the divided input torque command value Trq_ref / n for the multiple power converting units 10, 20, 30 so that the input voltages of the multiple power converting units 10, 20, 30 are equivalent. The divided input torque command value Trq_ref / n is a value obtained by dividing the input torque command value Trq_ref by the number n of the power converting units 10, 20, 30. Therefore, the divided input torque command value Trq_ref / n is the same value for the multiple power converting units 10, 20, 30.

[0034] Here, when the input sides of the multiple power conversion units 10, 20, 30 are electrically connected in series to the DC power source 3 as in this embodiment, even if the torque command values ​​Trq1, Trq2, Trq3 input to the power conversion units 10, 20, 30 are the same, the outputs of the power conversion units 10, 20, 30 may differ due to individual differences in the multiple power conversion units 10, 20, 30 and individual differences in the loads to which the multiple power conversion units 10, 20, 30 output power. This may cause variations in the DC input voltages Vdc1, Vdc2, Vdc3 of the multiple power conversion units 10, 20, 30, and further increase the variations in the outputs of the power conversion units 10, 20, 30. In response to this, the input voltage adjustment unit 50 can make the input voltages of the multiple power conversion units 10, 20, 30 equal.

[0035] In detail, as shown in FIG. 2, the input voltage adjusting unit 50 has an input voltage difference calculating unit 51, a PI control unit 52, and an input torque command correcting unit 53.

[0036] The input voltage difference calculation unit 51 calculates the difference between the DC input voltages Vdc1, Vdc2, Vdc3 of the power conversion units 10, 20, 30 and an average DC input voltage Vdc / n obtained by dividing the DC voltage Vdc of the DC power source 3 by the number n of the power conversion units 10, 20, 30. This makes it possible to find the deviation of the DC input voltages Vdc1, Vdc2, Vdc3 of the power conversion units 10, 20, 30 from the average DC input voltage Vdc / n.

[0037] The PI control unit 52 converts the voltage differences calculated by the input voltage difference calculation unit 51 into corresponding first torque command correction values ​​Trq_α1, Trq_α2, and Trq_α3 by performing PI control processing. The configuration of the PI control unit 52 is similar to that of a conventional one, and therefore a detailed description of the PI control unit 52 will be omitted.

[0038] The input torque command correcting unit 53 corrects the divided input torque command values ​​Trq_ref / n for the power conversion units 10, 20, and 30 using the first torque command correction values ​​Trq_α1, Trq_α2, and Trq_α3 calculated by the PI control unit 52, respectively.

[0039] This makes it possible to correct the divided input torque command value Trq_ref / n for the power conversion units 10, 20, and 30 so that the input voltages of the power conversion units 10, 20, and 30 become equal.

[0040] The torque command adjustment unit 60 equally divides the sum of the first torque command correction values ​​Trq_α1, Trq_α2, and Trq_α3 obtained by the input voltage adjustment unit 50 to obtain a second torque command correction value Trq_β, and corrects the divided input torque command value Trq_ref / n for the power conversion units 10, 20, and 30 using the second torque command correction value Trq_β.

[0041] Here, when the input voltage adjusting unit 50 corrects the divided input torque command values ​​Trq_ref / n for the power converting units 10, 20, 30 using the first torque command correction values ​​Trq_α1, Trq_α2, Trq_α3 as described above, the sum of the corrected torque command values ​​may deviate from the input torque command Trq_ref. The torque command adjusting unit 60 can suppress such deviation of the sum of the corrected torque command values ​​from the input torque command Trq_ref.

[0042] In detail, as shown in FIG. 2, the torque command adjustment unit 60 has a torque command correction value summing unit 61, a torque correction unit 62, and a torque command correction unit 63.

[0043] The torque command correction value summing unit 61 sums up the first torque command correction values ​​Trq_α1, Trq_α2, and Trq_α3 calculated by the input voltage adjusting unit 50 to calculate a first torque command correction total value Trq_αsum.

[0044] The torque corrector 62 calculates the first torque command correction sum Trq_αsum calculated by the torque command correction value adder 61, and divides the first torque command correction sum Trq_αsum by the number n of the power converters 10, 20, 30 to calculate the second torque command correction value Trq_β.

[0045] The torque command correction unit 63 corrects the divided input torque command value Trq_ref / n for the power conversion units 10, 20, 30 using the determined second torque command correction value Trq_β.

[0046] This makes it possible to correct the divided input torque command value Trq_ref / n so that the sum of the torque command values ​​after the divided input torque command value Trq_ref / n is corrected by the input voltage adjusting unit 50 matches the input torque command Trq_ref.

[0047] Therefore, the sum of the torque command values ​​Trq1, Trq2, and Trq3 for the power conversion units 10, 20, and 30 can be prevented from deviating significantly from the input torque command Trq_ref. Therefore, the power supplied to the motor 2 from the power conversion units 10, 20, and 30 can be prevented from deviating significantly from the power corresponding to the input torque command Trq_ref. Therefore, the output torque of the motor 2 can be controlled with high accuracy.

[0048] The power conversion device 1 according to the present embodiment includes a plurality of power conversion units 10, 20, and 30 whose input sides are electrically connected in series to a DC power source 3 and which supply power to a motor 2 according to an input torque command value Trq_ref. The power conversion device 1 includes an input voltage adjustment unit 50 that corrects divided input torque command values ​​Trq_ref / n input to the plurality of power conversion units 10, 20, and 30 according to the input torque command value Trq_ref so that the input side voltages of the plurality of power conversion units 10, 20, and 30 are equal to each other, and a torque command adjustment unit 60 that corrects the divided input torque command value Trq_ref / n using a second torque command correction value Trq_β obtained by dividing a first torque command correction sum value Trq_αsum, which is the sum of correction amounts of the divided input torque command values ​​Trq_ref / n by the input voltage adjustment unit 50, among the plurality of power conversion units 10, 20, and 30.

[0049] As a result, even when the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 is corrected so that the input side voltages electrically connected in series to the DC power source 3 in the multiple power conversion units 10, 20, 30 are equivalent, the sum of the torque command values ​​Trq1, Trq2, Trq3 after correction by the torque command adjustment unit 60 can be made to match the input torque command value Trq_ref.

[0050] Therefore, even when the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 is corrected so that the input side voltages of the multiple power conversion units 10, 20, 30 are equivalent, a power conversion device 1 capable of precise torque control can be provided so that the sum of the corrected torque command values ​​Trq1, Trq2, Trq3 matches the input torque command Trq_ref.

[0051] In this embodiment, the multiple power conversion units 10, 20, and 30 supply power to one motor 2.

[0052] In this way, when the multiple power conversion units 10, 20, 30 supply power to one motor 2, in order to accurately control the output torque of the motor 2, it is necessary to accurately control the power supplied from the multiple power conversion units 10, 20, 30 to the motor 2 in accordance with the input torque command value Trq_ref. Therefore, as in the above configuration, the output torque of the motor 2 can be accurately controlled by matching the sum of the torque command values ​​Trq1, Trq2, Trq3 for the multiple power conversion units 10, 20, 30 with the input torque command value Trq_ref.

[0053] In addition, in this embodiment, the torque command adjustment unit 60 divides the first torque command correction sum value Trq_αsum equally by the number n of the multiple power conversion units 10, 20, 30 to obtain a second torque command correction value Trq_β, and corrects each of the torque command values ​​using the second torque command correction value Trq_β.

[0054] This makes it possible to make the correction amounts of the divided input torque command values ​​Trq_ref / n for the multiple power conversion units 10, 20, 30 equal when correcting the divided input torque command values ​​Trq_ref / n for the multiple power conversion units 10, 20, 30 in accordance with the first torque command correction sum value Trq_αsum.

[0055] If the correction amount varies among the power conversion units, this may affect the control for correcting the divided input torque command values ​​so that the input voltages of the multiple power conversion units are equalized. In contrast, by making the correction amount equal among the multiple power conversion units 10, 20, and 30 as described above, it is possible to perform accurate and stable torque control.

[0056] Therefore, even if the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 is corrected so that the DC input voltages of the multiple power conversion units 10, 20, 30 are equivalent, a power conversion device 1 can be provided that can accurately and stably control torque so that the sum of the torque command values ​​Trq1, Trq2, Trq3 input to the multiple power conversion units 10, 20, 30 matches the input torque command value Trq_ref.

[0057] <Embodiment 2> 3 is a block diagram for explaining generation of a torque command value by a control unit of a power conversion device according to embodiment 2. In this embodiment, a configuration of a torque command adjustment unit 160 is different from that of the torque command adjustment unit 60 of embodiment 1. In the following, configurations similar to those in embodiment 1 are denoted by the same reference numerals and description thereof is omitted, and only configurations different from embodiment 1 will be described.

[0058] The torque command adjustment unit 160 calculates the difference between the first torque command correction sum value Trq_αsum calculated by the torque command correction value summation unit 61 and the input torque command value Trq_ref, and corrects the divided input torque command value Trq_ref / n using a second torque command correction value Trq_β', which is the ratio of the difference to the input torque command value Trq_ref.

[0059] In detail, as shown in FIG. 3, the torque command adjustment unit 160 has a torque command correction value summing unit 61, a torque correction unit 162, and a torque command correction unit 163.

[0060] 4 is a block diagram showing a schematic configuration of the torque correction unit 162. The torque correction unit 162 calculates the difference between the first torque command correction sum value Trq_αsum calculated by the torque command correction value adder 61 and the input torque command value Trq_ref. The torque correction unit 162 divides the calculated difference by the input torque command value Trq_ref to calculate the ratio between the difference and the input torque command Trq_ref. In this embodiment, the calculated ratio is the second torque command correction value Trq_β'.

[0061] The torque command correcting unit 163 multiplies the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 by the second torque command correction value Trq_β′ determined by the torque correcting unit 162, thereby correcting the divided input torque command Trq_ref / n.

[0062] In this embodiment, the torque command adjustment unit 160 calculates a second torque command correction value Trq_β' as the ratio of the value obtained by subtracting the first torque command correction sum value Trq_αsum from the input torque command value Trq_ref to the input torque command value Trq_ref, and corrects each torque command value by multiplying each torque command value by the second torque command correction value Trq_β'.

[0063] As a result, when the divided input torque command value Trq_ref / n input to the multiple power conversion units 10, 20, 30 is corrected according to the difference between the input torque command value Trq_ref and the first torque command correction total value Trq_αsum, the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 can be corrected at the same ratio using the ratio between the value obtained by subtracting the first torque command correction total value Trq_αsum from the input torque command value Trq_ref and the input torque command value Trq_ref.

[0064] Therefore, even if the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 is corrected so that the DC input voltages of the multiple power conversion units 10, 20, 30 are equivalent, a power conversion device can be provided that can accurately and stably control torque so that the sum of the torque command values ​​Trq1, Trq2, Trq3 input to the multiple power conversion units 10, 20, 30 matches the input torque command value Trq_ref.

[0065] (Other embodiments) Although the embodiment of the present invention has been described above, the above-mentioned embodiment is merely an example for carrying out the present invention. Therefore, the present invention is not limited to the above-mentioned embodiment, and it is possible to carry out the above-mentioned embodiment by appropriately modifying it within the scope of the gist of the present invention.

[0066] In each of the above embodiments, the multiple power conversion units 10, 20, 30 supply power to one motor 2. However, the multiple power conversion units may each supply power to a different load. Some of the multiple power conversion units may supply power to the same load. The load to which the multiple power conversion units supply power may be a load other than a motor.

[0067] In each of the above-described embodiments, the power conversion device 1 has three power conversion units 10, 20, and 30. However, the power conversion device may have two or four or more power conversion units.

[0068] In each of the above-described embodiments, the power supply that supplies power to the power conversion device 1 is a DC power supply 3. However, the power supply that supplies power to the power conversion device may be another power supply, such as an AC power supply.

[0069] In each of the above-described embodiments, the input voltage adjustment unit 50 corrects the divided input torque command value Trq_ref / n for the multiple power conversion units 10, 20, 30 so that the input voltages of the multiple power conversion units 10, 20, 30 are equivalent. The input voltages of the multiple power conversion units being equivalent includes not only the case where the input voltages of the multiple power conversion units are equal, but also the case where the input voltages of the multiple power conversion units have an error that does not affect the output.

[0070] In the first embodiment, the torque correction unit 62 of the torque command adjustment unit 60 equally divides the difference between the input torque command value Trq_ref and the first torque command correction sum value Trq_αsum among the multiple power conversion units 10, 20, and 30 to obtain the second torque command correction value Trq_β. However, the torque correction unit may divide the difference in different allocations among the multiple power conversion units to obtain the second torque command correction value. In this case, the torque correction unit may, for example, obtain the second torque command correction value so as to distribute the difference to the multiple power conversion units according to the outputs of the multiple power conversion units, or may obtain the second torque command correction value so as to distribute the difference to the multiple power conversion units according to the voltage adjustment amount (e.g., the output value of a PI control unit) on the input side of the multiple power conversion units by an input voltage adjustment unit. Furthermore, the torque correction unit may obtain the second torque command correction value so as to distribute the difference to the multiple power conversion units at a ratio obtained in advance.

[0071] Similarly, in the second embodiment, the second torque command correction value Trq_β′ may be a different ratio for the multiple power conversion units. That is, the second torque command correction value may be a different ratio depending on the outputs of the multiple power conversion units, or may be a different ratio depending on the voltage adjustment amount (e.g., the output value of a PI control unit) on the input side of the multiple power conversion units by an input voltage adjustment unit. Moreover, the second torque command correction value may be a predetermined ratio.

[0072] In the first embodiment, the control unit 40 of the power conversion device 1 corrects the divided input torque command value Trq_ref / n by the input torque command correction unit 53, and then corrects the divided input torque command value Trq_ref / n by the torque command correction unit 63 using the second torque command correction value Trq_β. However, the control unit may correct the divided input torque command value by the input torque command correction unit after correcting the divided input torque command value by the torque command correction unit using the second torque command correction value. Similarly, in the second embodiment, the order of the correction of the divided input torque command value Trq_ref / n by the input torque command correction unit 53 and the correction of the divided input torque command value Trq_ref / n by the torque command correction unit 163 may be interchanged. [Industrial Applicability]

[0073] INDUSTRIAL APPLICABILITY The present invention can be used in a power conversion device having a plurality of power conversion units whose input sides are electrically connected in series to a power source and which supply electric power to a motor in response to a torque command. [Explanation of symbols]

[0074] 1 Power conversion device 2 Motors 3 DC power supply 10, 20, 30 Power conversion section 21, 22, 23 Stator coil 40 Control section 41 Torque command generator 50 Input voltage adjustment section 51 Input voltage difference calculation section 52 PI control section 53 Input torque command correction unit 60, 160 Torque command adjustment unit 61 Torque command correction value summing unit 62, 162 Torque compensation section 63 Torque command correction unit

Claims

1. A power conversion device having a plurality of power conversion units each having an input side electrically connected in series to a power source and supplying power to a load in response to an input torque command value, an input voltage adjusting unit that corrects divided input torque command values ​​that are input to the plurality of power converting units in accordance with the input torque command value so that input side voltages of the plurality of power converting units are equal to each other; a torque command adjustment unit that corrects the divided input torque command value by using a torque command correction value obtained by dividing a total amount of correction of the divided input torque command value by the input voltage adjustment unit into the plurality of power conversion units; having Power conversion equipment.

2. 2. The power conversion device according to claim 1, The plurality of power conversion units supply power to one load. Power conversion equipment.

3. 3. The power conversion device according to claim 1, the torque command adjustment unit obtains the torque command correction value by equally dividing the total of the correction amounts by the number of the plurality of power conversion units, and corrects each of the torque command values ​​using the torque command correction value. Power conversion equipment.

4. 3. The power conversion device according to claim 1, the torque command adjustment unit calculates a ratio of a value obtained by subtracting the sum of the correction amounts from the input torque command value, to the input torque command value, as the torque command correction value, and corrects the divided input torque command value by multiplying the divided input torque command value by the torque command correction value. Power conversion equipment.

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