JP6637165B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter that drives an AC load.

  As a background art of the technical field to which the present invention belongs, there is JP-A-2004-348662 (Patent Document 1). This publication states that “When the power switch 25 is pressed, the CPU 11 starts the BIOS stored in the BIOS-ROM 18 and executes system initialization. In this system initialization processing, the system configuration determination unit 181 The system configuration is determined by acquiring various device information, and the AC adapter 1 is estimated, and the AC adapter setting section 182 registers the PSC 26 to execute the maximum rated current control corresponding to the estimated AC adapter 1. 261. On the other hand, the PSC 26 executes the maximum rated current control corresponding to the AC adapter 1 indicated by the value of the register 261. When the system initialization is completed, the CPU 11 stores the data in the HDD 20. The OS is loaded into the system memory 13 and activated. " (See summary)

JP 2004-348662 A

  Patent Literature 1 describes a method of estimating an AC adapter from a configuration of a system of an electronic device and performing maximum rated current control for the estimated AC adapter. In general-purpose power converters, when the method of Patent Literature 1 is adopted for a power converter and a system is to be recognized, a system connected to a general-purpose power converter is largely changed by a user. different.

  General-purpose power converters are used in, for example, light-load systems such as fans and pumps, medium-load systems such as conveyors and take-ups, and heavy-load systems such as cranes and lifts. Therefore, the combination of the systems is different for each user, and the load current and the operation frequency are greatly different. Therefore, in a general-purpose power converter, when a system shown in Patent Literature 1 is used to estimate a connected system and to detect a maximum rated current required for the power converter, the system is operated by a user. Therefore, there is a problem that the combination of the use, the load current, and the operation frequency becomes very large, and the estimation becomes very difficult.

  In Patent Document 1, the load current of an AC adapter connected to a personal computer can be estimated in advance. On the other hand, in the power converter, the magnitude and the increase / decrease frequency of the current flowing by the operation of the power converter set by the user differ from the system connected by the user. Therefore, when a user selects a power converter, if a power converter having a large margin with respect to a system constructed by the user is employed, there is no problem in the operation state, but the cost is greatly increased. On the other hand, if the power converter is strictly selected according to the system constructed by the user, it is necessary to check the operation state and the like in a trial run.Whether the power converter is optimal or has too much room Is difficult to judge.

  In order to solve the above problems, a power converter according to the present invention includes an AC converter that outputs AC power, a current detector that detects a current flowing through the AC converter, and a current operation that is detected by the current detector. A storage unit for storing, a determination unit for determining an optimum value of the rated current value, and a display / operation unit for command operation and output display, wherein the determination unit receives a rating determination command from the display / operation unit. The optimum value of the rated current value is determined by comparing the current operation input from the storage unit with various current reference values at a predetermined rated capacity, and the setting of the optimum value of the rated current value is displayed on the display / operation unit. It is characterized by output display.

Advantageous Effects of Invention According to the present invention, it is possible to provide a mechanism for automatically determining an optimal power converter suitable for a system constructed by a user and a rating setting thereof.
Problems, configurations, and effects other than those described above will be apparent from the following description of the embodiments.

FIG. 1 is a diagram illustrating an example of a configuration of the power conversion device according to the first embodiment of the present invention. FIG. 2 is a flowchart illustrating a determination procedure by the optimal determination unit 112 included in the power conversion device according to the first embodiment. FIG. 3 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the first embodiment. FIG. 4 is a table showing a relationship between a plurality of power converters having different rated capacities of adaptive motors, a plurality of rated currents, and a plurality of protection currents in the first embodiment. FIG. 5 illustrates a state where the display / operation unit 115 according to the first embodiment is displaying a state. FIG. 6 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the second embodiment. FIG. 7 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the third embodiment. FIG. 8 is a table illustrating a reference example of the rated current and the cycle of the power conversion device according to the third embodiment. FIG. 9 is a table illustrating a relationship between a plurality of power conversion devices having different adaptive motor rated capacities, a plurality of rated currents, and a plurality of protection currents in the fourth embodiment. FIG. 10 is a diagram illustrating an example of a configuration of a power conversion device according to a fifth embodiment of the present invention. FIG. 11 is a flowchart illustrating a determination procedure by the optimal determination unit 112 included in the power conversion device according to the fifth embodiment. FIG. 12 is a diagram illustrating an example of a temperature operation detected based on an acquisition command by automatic setting in the fifth embodiment. FIG. 13 is a table illustrating a reference example of the operating temperature and the cycle of the power converter according to the fifth embodiment.

Examples 1 to 5 will be described below as embodiments of the present invention with reference to the drawings.
In each of the following embodiments, an operation example in which an optimal power converter and its rating are determined by automatic setting in a test run of a power converter that drives an AC load such as an AC motor connected to a user system will be described.

FIG. 1 is a diagram illustrating an example of a configuration of a power conversion device according to a first embodiment of the present invention and an AC motor used by a user system connected to the power conversion device.
The power conversion device according to the present invention includes a three-phase AC power supply 101, a DC conversion unit 102, a smoothing capacitor 103, an AC conversion unit 104, a current detector 106, a control unit 111, an optimum determination unit 112, a storage unit 113, and a current detection unit. 114 and a display / operation unit 115. Then, the AC motor 105 is driven and driven by the power converter according to the present invention.

The three-phase AC power supply 101 is, for example, a three-phase AC voltage supplied from a power company or an AC voltage supplied from a generator, and is an input of the DC converter 102.
The DC converter 102 includes, for example, a DC converter using a diode or a DC converter using an IGBT and a flywheel diode. The DC converter 102 converts an AC voltage input from the three-phase AC power supply 101 into a DC voltage and outputs the DC voltage to the smoothing capacitor 103. DC converter 12 shown in FIG. 1 is an example of a DC converter configured with a diode.

Smoothing capacitor 103 smoothes the DC voltage input from DC converter 102 and outputs it to AC converter 104. When the output of the generator is a DC voltage, the smoothing capacitor 103 may directly input the DC voltage from the generator without passing through the DC converter 102.
The AC conversion unit 104 is configured by an AC conversion circuit using, for example, an IGBT and a flywheel diode. With the DC voltage of the smoothing capacitor 103 as an input, the DC voltage is converted into an AC voltage according to an output command of the control unit 111 and output to the AC motor 105. When the AC converter 104 is configured by an AC converter that performs AC-AC conversion without passing through the smoothing capacitor 103, the AC converter 104 converts an input AC voltage into an AC voltage having a different frequency and outputs the AC voltage to the AC motor 105. May be.

  The current detector 106 includes, for example, a Hall CT and a shunt resistor. Current detector 106 is arranged on the output side of the power converter, detects an AC current flowing through AC motor 105, and outputs the detected current data to current detection unit 114 as detected current data. The current detector 106 may be placed anywhere as long as it is placed at a place where the output current flowing to the AC converter 104 can be estimated or directly detected. FIG. 1 is an example of detecting a current flowing through AC motor 105.

Control unit 111 provides a PWM output command to AC conversion unit 104 using current operation data of the detected current fed back from current detection unit 114 in accordance with an output command calculated from a command for driving AC motor 105.
Based on the current operation detection command input from the display / operation unit 115, the optimum determination unit 112 determines the input information as trigger information for current operation detection, and instructs the storage unit 113 to acquire the current operation. The current operation detection command instructed from the display / operation unit 115 is, for example, an ON / OFF signal command, a signal in an operating state, time designation from the start setting, and the like, and determines the start / end of the current operation detection command. . Here, when it is determined that the current operation has ended, the current operation characteristics stored in the storage unit 113 are acquired. The optimum determination unit 112 determines the optimum value of the rated value from the current operation input from the storage unit 113 and outputs the value to the display / operation unit 115.

The storage unit 113 includes, for example, an element (RAM or the like) that temporarily stores data, an EEPROM or a data flash ROM that retains the storage even when the power is turned off, and receives a command from the display / operation unit 115 as set value data. The current operation data from the current detection unit 114 is stored as detection value data. The storage unit 113 outputs the current operation data to the optimal determination unit 112.
The current detection unit 114 converts, for example, the detected current data input from the current detector 106 into current operation data for calculation, and outputs the current operation data to the control unit 111 and the storage unit 113.

  The display / operation unit 115 indicates a user interface such as a smartphone, a smart watch, a tablet terminal, or a personal computer, which includes, for example, an operation panel and input / output terminals. For example, input information operated by the user or an input signal obtained from an external device is output to the optimal determination unit 112.

FIG. 2 is a flowchart illustrating a procedure of the automatic setting performed by the optimal determination unit 112.
When performing the rating judgment by the automatic setting, the optimum judgment unit 112 first obtains trigger information for starting the judgment of the rating judgment command from the display / operation unit 115 in step 201 (S201) to start the rating judgment. (S201).
In step 202 (S202), the optimal determination unit 112 determines whether it is a trigger to start the determination. If there is a trigger (Yes), in step 203 (S203), the current operation acquisition command is stored in the storage unit 113. Command.

In step 204 (S204), the optimum judgment unit 112 inputs a rating judgment command from the display / operation unit 115 and updates the state of the current operation acquisition command.
In step 205 (S205), the optimal determination unit 112 determines whether the updated current operation acquisition command state satisfies the operation acquisition end condition (S205). If the state does not satisfy the operation acquisition end condition (No). Returning to step 203 (S203), the current operation acquisition command is continuously issued to the storage unit 113. If the operation acquisition end condition is satisfied (Yes), the optimal judgment unit 112 judges whether or not the operation has ended normally in step 206 (S206).

  For example, when it is desired to make a determination in one cycle of operation, the optimal determination unit 112 obtains the operation state from the control unit 111, causes the storage unit 113 to obtain the current operation when the operation is started, and stops the operation. At this point, it is determined to be finished. In addition, when the user wants to determine the rating setting from the operation for one day, the operation setting is performed from the display / operation unit 115, and the optimal determination unit 112 uses the acquired start signal as a trigger, and the start signal is input. It is determined that the operation is completed after counting for 24 hours from.

  When the normal termination is detected from the determination of the normal termination in step 206 (S206) (Yes), the optimal determination unit 112 acquires the current operation in step 207 (S207), and subsequently, in step 208 (S208). Then, the optimum value of the rated value is determined from the current operation. Here, the current operation to be acquired may be, for example, current waveform data in the detection state, or an allowable level of the current setting determined in advance by the power converter, and how often and how much the allowable level is set. May be data that stores whether the time has passed. Then, in step 209 (S209), the optimum judgment unit 112 notifies the display / operation unit 115 of the optimum value of the rated value.

  On the other hand, when the abnormal termination is detected in step 206 (S206) (No), the optimal determination unit 112 acquires the current operation in step 210 (S210). If there is a possibility that the rated capacity of the power conversion device is insufficient, or if the error is due to other factors, it is determined that there is a system abnormality, and the result of the determination is displayed in step 211 (S211) on the display / operation unit 115. (S211).

FIG. 3 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the first embodiment.
In FIG. 4, (1) shows an example of a plurality of power converters having different rated capacities determined according to the applied AC motor capacity, and (2) shows a relationship between a plurality of rated currents and a plurality of protection currents. Is shown. The device used for the test run in the first embodiment is the device 1. The rated capacity is represented by the product of the rated voltage and the rated current. When the voltage is constant, the rated capacity and the rated current have an equivalent relationship.

  FIG. 3 shows how the start and end of the automatic setting (current operation detection section) are determined based on the output state. Here, from the detected current operation, the optimal determination unit 112 detects for how long currents at or above various current reference values at the rated capacity predetermined for each power converter have been flowing. Then, each setting of the rated capacity and the rated current is comprehensively determined by the optimum determination unit 112 from, for example, the temperature characteristics of the hardware of the AC conversion unit 104. As for a power converter having a plurality of capacity lineups, a power converter having a higher rated current as a whole is more expensive. For example, in FIG. 4, device 1 is the most expensive and device 3 is the least expensive. The characteristics of a single power conversion device are that the higher the rated current, the faster it is necessary to provide protection when used in a state that exceeds the rated current, the lower the operating temperature and other limits, and the lower the error level for the rated current. Lower. Regarding the setting of the protection current, for example, as shown in the relationship between (1) and (2) in FIG. 4, the rating 6-1 is 110% of the rated current for 60 seconds, and the rating 6-2 is 120% of the rated current. It is assumed that the device can withstand 60 seconds at a rated current of 150% for 60 seconds with a rating of 6-3 and 180% of the rated current for 60 seconds with a rating of 6-4 until an error occurs to protect the element. These currents can be set with a margin for the damage level of the element.

  The optimum determination unit 112 measures the time from the current operation acquired through the storage unit 113. The optimal determination unit 112 acquires the current operation in real time from the storage unit 113 (in FIG. 2, acquired in step 204 (S204)), or collectively acquires the current operation after the current acquisition command ends (in FIG. 2, , Acquired in step 207 (S207)). In the current operation of FIG. 3, for example, a state in which operation is continuously performed at 38 A for 60 seconds (a−1), at 28 A for 100 seconds (b−1), and at 28 A for 400 seconds (c−1) is shown. . In addition, the optimum determination unit 112 may measure the excess time of the current based on, for example, a current value determined in advance by the characteristics of the power conversion device illustrated in FIG. 4, and necessarily obtains all continuous current values. You do not need to judge.

  Here, based on various current reference values, the optimum determination unit 112 can determine that the rated current value needs to exceed 28 A in order to operate at, for example, 30 A or less for 60 seconds or more. That is, in the table relating to the rated current in FIG. 4A, a combination of the device and the rated current value exceeding 28 A is a selection candidate. That is, as the selection candidates from the rated current values, the device 1 is rated 6-1, 6-2 and 6-3, the device 2 is rated 6-1 and 6-2, or the device 3 is rated 6 -6. 1 corresponds to this.

  In addition, since the optimal determination unit 112 operates at 38 A for 60 seconds in the current operation shown in FIG. 3, it can determine that the protection current value needs to be selected to exceed 38 A. That is, in the protection current table of FIG. 4B, a combination of a device and a rating having a protection current value exceeding 38 A is a selection candidate. In other words, the selection candidates from the protection current values correspond to the ratings 6-1, 6-2 and 6-3 in the device 1, or the ratings 6-1 in the device 2.

Therefore, the optimum determination unit 112 selects a device and a rating from candidates satisfying both the rated current value and the protection current value. For example, in the first embodiment, since the rating 6-1 of the device 2 which is cheaper than the device 1 can be selected, it is determined that the rating 6-1 of the device 2 is optimal.
Further, the optimum judgment unit 112 may judge the optimum value of the rated value for each power conversion device. When the device 1 is employed, the use temperature limit is high, and there is a margin until an error occurs. Among them, it may be determined that the rating 6-3 of the apparatus 1 is optimal, and the user may select an optimal setting from a plurality of candidates.
Furthermore, in the first embodiment, when the optimum rating setting of the device 1 itself that has determined the automatic setting is selected in the first embodiment, the setting of the device 1 is automatically changed as the optimum setting value. can do.

FIG. 5 is a diagram illustrating a state in which the display / operation unit 115 receives the notification of the optimum value from the optimum determination unit 112 and displays the state. When the displayed optimum value is selected by the user and the setting is the setting of the device 1 itself, the display / operation unit 115 automatically changes the setting of the power conversion device without displaying it, for example. Or the message "Do you want to apply the settings as is?" And the like, and if the user approves, a setting may be automatically made in the power converter. When the optimal device is different from the one at the time of the test run, for example, the display / operation unit 115 performs the test run with the device 1 in the first embodiment, but when the user specifies the device 2, the display content is “ Need to be replaced. May be issued to prompt the user to change the device.
As described above, it is possible to determine the optimum power converter and its rating setting.

This embodiment is a modification of the first embodiment. However, the configuration of the second embodiment has the same functions as those of the components having the same reference numerals shown in FIG. .
In the second embodiment, it is assumed that the user system connected to the AC motor 105 has a heavier load than that of the first embodiment.

FIG. 6 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the second embodiment.
FIG. 6 shows a state in which the operating current has grown (increased) to a current level at which the power conversion device recognizes an abnormality. As in the first embodiment, the optimal determination unit 112 starts the determination operation using the output state as a trigger in the procedure shown in FIG. For example, if the current error level of the current converter is 80 A, an error is issued when the operating current reaches 80 A, and the state is updated (FIG. 2, step 204 (S204)). When the error is detected, the optimum determination unit 112 determines that the operation is abnormal termination (step 206 (S206) in FIG. 2), and acquires the current operation (step 210 (S210) in FIG. 2).

In the second embodiment, since it is determined that there is an error due to an error due to the detected current operation, the optimal determination unit 112 determines that there is a possibility that the rated capacity and the rated current of the power conversion device may be low. In addition to the notification of the abnormality, it notifies that the capacity is insufficient. The display / operation unit 115 displays abnormal termination and a state where the capacity of the power converter is insufficient. Thus, if there is no abnormality in the system operation, the user can determine that a higher-order capacity is required.
As described above, it is possible to determine whether or not the rating can be set even when the power converter having the required capacity is not attached to the system.

This embodiment is also a modification of the first embodiment, but the configuration of the third embodiment has the same function as the configuration with the same reference numeral shown in FIG. 1 already described, and thus the description thereof will be omitted. .
In the third embodiment, the current operation detection command received by the display / operation unit 115 and the content of the determination by the optimal determination unit 112 are different from those in the first embodiment. In the third embodiment, in order to determine from the operation of the user system in one day, regardless of the output of the power converter, for example, 24 hours are measured from the time designated by the user, and the detection is automatically performed after the current operation is detected. finish.

FIG. 7 is a diagram illustrating an example of a current operation detected based on an acquisition command based on automatic setting in the third embodiment.
FIG. 8 is a table showing reference examples of the rated current value and the power cycle of the power converter. The power cycle is, for example, the number of cycles of the life due to the thermal stress of the IGBT module, and can be calculated from the power cycle capability provided by the IGBT element maker or the like based on the rise and fall of the temperature of the module. In the third embodiment, the temperature rises due to the current flowing through the module, and the temperature falls due to the interruption of the current. Therefore, an example in which the number of power cycles per day which becomes the life from this current operation is simulated. FIG.

  In the detected current operation of FIG. 7, for example, a state is shown in which the system is connected to a system in which a steady operation with a current value of 25 A or less is performed 20 cycles in a day's operation. For example, the optimum determination unit 112 may measure based on the rated current value and the power cycle determined in advance by the characteristics of the power converter illustrated in FIG. 8, and it is necessary to acquire and determine all continuous current values. No need.

The optimum determining unit 112 determines a device that can operate at a current value of 25 A for 20 cycles or more based on the detected current operation in FIG. That is, in the table of FIG. 8, a combination in which the rated current value and the power cycle exceed 25 A and 20 cycles is a selection candidate.
Selection candidates satisfying both the rated current value and the cycle correspond to ratings 8-2 and 8-3 in the device 1, or ratings 8-2 in the device 2. In the third embodiment, since the rating 8-2 of the device 2 which is cheaper than the device 1 can be selected, it is determined that the rating 8-2 of the device 2 is optimal.

Further, the optimum determination unit 112 may determine the optimum value of the rated value for each power conversion device. In the case of employing the device 1 in FIG. 8, the use temperature limit is high and there is a margin until an error occurs. Therefore, it is determined that the rating 8-3 of the device 1 is optimal among the candidates. Alternatively, the user may be allowed to select an optimum setting from a plurality of candidates.
As described above, it is possible to determine the optimum power converter and its rating setting.

This embodiment is a modification of the first embodiment. However, the configuration of the fourth embodiment has the same functions as those of the configuration with the same reference numerals shown in FIG. 1 described above, and a description thereof will be omitted. .
The fourth embodiment differs from the first embodiment in the content of the judgment made by the optimum judgment unit 112. The fourth embodiment is suitable, for example, when a user wants to select a power conversion device with a margin. Specifically, it is assumed that the user wants to set the rated current with a margin of 10 A from the standard selection reference value.

  When 10A is set as a margin value in the power conversion device through the display / operation unit 115, in the determination of the rated current value performed in the first embodiment, the optimal determination unit 112 determines the reference value of FIG. As in 9 (1), the judgment is executed by subtracting 10 A from all. That is, in the current operation of FIG. 3, the optimal determination unit 112 continuously performs, for example, 60 seconds (a−1) at 38 A, 100 seconds (b−1) at 28 A, and 400 seconds (c−1) at 28 A. The operation is shown.

  Since the optimal determination unit 112 operates at 30 A or less for 60 seconds or more, it can be determined that the rated current value needs to exceed 28 A. That is, in the table related to the rated current in FIG. 9A, a combination of a device having a rated current value exceeding 28 A and a rating is a selection candidate. As candidates for selection from the rated current values, ratings 9-1 and 9-2 in the device 1 or ratings 9-1 in the device 2 correspond.

Further, since the optimum determination unit 112 operates at 38 A for 60 seconds, it can be determined that the protection current value needs to be selected to exceed 38 A. That is, in the protection current table of FIG. 9B, a combination of a device having a protection current value exceeding 38 A and a rating is a selection candidate. Here, the protection current value is calculated by the ratio from the rated current value as in the first embodiment. As a selection candidate from the protection current value, only the rating 9-1 in the device 1 is selected. Therefore, the optimal determination unit 112 determines that the rating 9-1 of the device 1 that is a candidate that satisfies both the rating current value and the protection current value is satisfied. Determine that it is optimal.
As described above, it is possible to determine an optimal power converter with a margin and its rated setting.

This embodiment is a modification of the first embodiment. However, as for the configuration of the fifth embodiment having the same functions as those of the already-shown components denoted by the same reference numerals shown in FIG. Omitted.
FIG. 10 is a diagram illustrating a configuration of a power conversion device according to a fifth embodiment and an example of an AC motor used by a user system connected to the power conversion device.
The fifth embodiment focuses on the temperature operation while the first embodiment focuses on the current operation. The first embodiment is different from the first embodiment in that the temperature detector 1001 and the temperature detection unit 1014 are provided. The judgment contents of the unit 112 are different.

The temperature detector 1001 is, for example, a thermistor resistor, and detects the temperatures of six IGBTs arranged in the AC converter 104 and outputs detected temperature data to the temperature detector 1014.
The temperature detection unit 1014 converts the detected temperature data input from the temperature detector 1001 into temperature operation data for calculation, and outputs it to the control unit 111 and the storage unit 113.

  The detection value data stored in the storage unit 113 is the temperature operation data from the temperature detection unit 1014. The storage unit 113 outputs the temperature operation data to the optimal determination unit 112.

FIG. 11 is a flowchart illustrating a procedure of automatic setting performed by the optimal determination unit 112. Steps that perform the same operations as in FIG. 2 are given the same reference numerals.
In the following, only steps different in operation from the flowchart shown in FIG. 2 will be described.
In step 202 (S202), when the optimal determination unit 112 determines that there is a trigger to start the determination (Yes), in step 1103 (S1103), it issues a temperature operation acquisition command to the storage unit 113.

  In step 206 (S206), the optimal determination unit 112 determines whether the temperature operation acquisition has been completed normally or abnormally. For example, when it is desired to make a determination in one cycle of operation, the optimal determination unit 112 obtains the operation state from the control unit 111, causes the storage unit 113 to obtain the temperature operation when the operation is started, and stops the operation. At this point, it is determined to be finished. Further, for example, when the user wants to judge the setting of the rating from the operation for one day, the operation setting is performed from the display / operation unit 115, and the optimum judgment unit 112 uses the acquired start signal as a trigger and inputs the start signal. It is determined that the processing is completed after counting for 24 hours from the start.

  In step 206 (S206), when the optimal determination unit 112 detects the normal end of the temperature operation acquisition (Yes), the temperature operation is acquired in step 1107 (S1107), and then, in step 208 (S208), the temperature operation is acquired. Judge the optimal value of the rated value from the operation. Here, as the temperature operation to be acquired, for example, temperature waveform data in the detection state may be used, or an allowable level for temperature setting determined in advance by the power conversion device may be stored in advance, and how often and how much the allowable level is set. May be data that stores whether the time has passed.

  On the other hand, in step 206 (S206), when the optimum judgment unit 112 detects abnormal termination of temperature operation acquisition (No), in step 1110 (S1110), the temperature operation is acquired. If there is a possibility that the rated capacity of the operating power converter is insufficient, or if the error is due to other factors, it is determined that there is a system abnormality, and the determination result is displayed in step 211 (S211). The operation unit 115 is notified.

FIG. 12 is a diagram illustrating an example of a temperature operation detected based on an acquisition command by automatic setting in the fifth embodiment. FIG. 13 is a table showing a reference example of the operating temperature and the power cycle of the power converter.
In the detected temperature operation of FIG. 12, for example, a state in which a steady operation at 80 ° C. or less is connected to a system in which 20 cycles are performed in one day of operation is shown. The optimum determination unit 112 may measure the temperature and the power cycle determined in advance by the characteristics of the power converter shown in FIG. 13, for example, and it is not always necessary to obtain and determine all continuous temperatures.

The optimal determination unit 112 determines a device that can operate at 80 ° C. for 20 cycles or more based on the detected temperature operation in FIG. That is, in the table of FIG. 13, a combination in which the temperature and the power cycle are 80 ° C. and 20 cycles or more is a selection candidate. Selection candidates satisfying both the temperature and the power cycle correspond to the ratings 12-1 and 12-2 in the device 1, the ratings 12-1 in the device 2, or the ratings 12-1 in the device 3. In the fifth embodiment, since the rating 12-1 of the device 3 which is cheaper than the devices 1 and 2 can be selected, it is determined that the rating 12-1 of the device 3 is optimal.
Further, the optimum determination unit 112 may determine an optimum rating for each power conversion device. When the device 1 is employed, the use temperature limit is high, and there is a margin until an error occurs. It is determined that the rating 12-2 of the device 1 is optimal. Alternatively, the user may be allowed to select an optimum setting from a plurality of candidates.
As described above, even when focusing on the temperature operation, it is possible to determine the optimum power converter and its rating setting.

Note that the present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described above.
Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of one embodiment can be added to the configuration of another embodiment. Also, for a part of the configuration of each embodiment, it is possible to add, delete, or replace another configuration.

  Further, the processes (functions) and the like executed by the above-described optimal determination unit may be partially or entirely realized by hardware, for example, by designing an integrated circuit. It may be realized by software by interpreting and executing a program for realizing (function). Information such as programs, tables, and files for that purpose can be stored in a recording device such as a memory, a hard disk and an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, and a DVD.

101: three-phase AC power supply, 102: DC converter, 103: smoothing capacitor, 104: AC converter, 105: AC motor, 106: current detector, 111: control unit, 112: optimal judgment unit, 113: storage unit .., 114... Current detection unit, 115... Display / operation unit, 1001. Temperature detector, 1014.

Claims (9)

An AC converter that outputs AC power,
A current detector that detects a current flowing through the AC converter,
A storage unit that stores the current operation detected by the current detection unit,
A judging unit for judging an optimum value of the rated current value;
It has a display and operation unit for command operation and output display,
The determination unit receives a rating determination command from the display / operation unit, and compares the current operation input from the storage unit with various current reference values at a predetermined rated capacity to thereby obtain an optimum rated current value. And a setting of the optimum value of the rated current value is output and displayed on the display / operation unit. The power converter according to claim 1,
The storage unit stores the current operation only during a valid period of the rating determination command,
The power conversion device, wherein the current operation input from the storage unit is the current operation stored in the storage unit only during the valid period. The power converter according to claim 1 or 2,
The power converter wherein the current operation input from the storage unit is a frequency and a time at which the detected current exceeds a current allowable level determined by the power converter. It is a power converter according to any one of claims 1 to 3,
According to the adaptive load, the determination unit is based on a plurality of rated current values provided in the power conversion device or a plurality of rated current values provided in another power conversion device having a different rated current value from the power conversion device. A power converter that selects a rated current value closest to an optimum value of the rated current value. The power converter according to claim 4, wherein
The determining unit receives the setting of the margin current value from the display / operation unit, and calculates the optimum value of the rated current value from the plurality of rated current values provided in the power conversion device or the another power conversion device. A power converter, wherein a rated current value closest to a value lower than the margin current value is selected. An AC converter that outputs AC power,
A current detector that detects a current flowing through the AC converter,
A storage unit that stores the current operation detected by the current detection unit,
A judging unit for judging an optimum value of the rated current value;
It has a display and operation unit for command operation and output display,
The determination unit receives a rating determination command from the display / operation unit, and performs a current operation for a predetermined period input from the storage unit and a power cycle characteristic indicating a life of a semiconductor element module included in the AC conversion unit. A power converter that determines the combination of the optimum value of the rated current value and the power cycle by comparing the power cycle with each other, and that the setting of the combination is output and displayed on the display / operation unit. The power converter according to any one of claims 1 to 6,
The determining unit, when detecting the error information of the power conversion device, determines that the rated capacity of the power conversion device may be insufficient if the error is due to the current operation input from the storage unit, A power conversion device characterized in that if an error is caused by a factor other than the current operation, it is determined that there is a system abnormality, and the result of the determination is output and displayed on the display / operation unit . An AC converter that outputs AC power,
A temperature detection unit that detects a temperature generated in the AC conversion unit,
A storage unit that stores the temperature operation detected by the temperature detection unit,
A judging unit for judging an optimum value of the rated current value;
Display / operation unit for command operation and output display
With
The determination unit receives a rating determination command from the display / operation unit, and receives a temperature operation for a predetermined period input from the storage unit and a power cycle characteristic indicating a life of a semiconductor element module included in the AC conversion unit. A power converter that determines a combination of the optimum value of the rated current value and the power cycle by comparing the power cycle with each other, and displays the setting of the combination on the display / operation unit. It is a power converter of Claim 8, Comprising:
The determining unit, when detecting the error information of the power conversion device, determines that the rated capacity of the power conversion device may be insufficient if an error due to the temperature operation input from the storage unit, If the error is due to a factor other than the temperature operation, it is determined that there is a system abnormality, and the determined result is output and displayed on the display / operation unit.
A power converter characterized by the above-mentioned.

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