Power conversion device, information processing device, and information processing method

Abstract

The present invention provides a power conversion device, an information processing device, and an information processing method, which can distinguish an abnormality in cooling performance associated with an abnormality of a blower unit that blows air to a cooling structure unit from an abnormality in cooling performance associated with the presence of foreign matter, and can notify a user of the period of forced operation stop of the power conversion device accompanied by a temperature rise of the cooling structure unit. The power conversion device according to one embodiment of the present invention includes: power devices (semiconductor diode SD and semiconductor switch SW); a cooling structure unit for dissipating heat of the power devices; a cooling fan for blowing air to the cooling structure unit; and a diagnosis unit for diagnosing an abnormality related to the cooling performance based on the tendency of the temporal change of the temperature difference Y between the temperature Tf of the cooling structure unit (cooling heat sink unit 194) and the temperature Ta of the air inside the power conversion device (housing).

Description

Technical Field

[0001] The present invention relates to a power conversion device and the like. Background Art

[0002] For example, in a power conversion device, a method for determining cooling anomalies such as blockages in a cooling structure portion for heat dissipation of a power device using a heat sink or the like, and failures in a blower portion that blows air to the cooling structure portion of a fan or the like has been disclosed (for example, refer to Patent Document 1).

[0003] In addition, a technique has been disclosed in which, when a blockage (clogging) occurs in a cooling structure portion such as a cooling heat sink for heat dissipation of a heating element, the predicted time until the predicted cooling performance deteriorates significantly is notified to the user (for example, refer to Patent Document 2).

[0004] <Prior Art Documents>

[0005] <Patent Documents>

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2010 - 136609

[0007] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2009 - 295644 Summary of the Invention

[0008] <Problems to be Solved by the Invention>

[0009] However, in Patent Document 1 and the like described above, although it is possible to determine the presence or absence of an abnormality in the cooling performance, it is not possible to determine whether the abnormality that has occurred is an abnormality in the cooling performance accompanied by the presence of foreign matter such as a blockage in the cooling structure portion, or an abnormality in the cooling performance accompanied by an abnormality in the blower portion. Therefore, for example, there is a possibility that, although no abnormality has occurred in the blower portion, the blower portion is replaced, resulting in an increase in the operating cost of the power conversion device.

[0010] In addition, in Patent Document 2 and the like described above, in a power conversion device including a power device, sometimes when the temperature of a cooling structure portion such as a cooling heat sink for heat dissipation of the power device reaches a specified reference, the operation is forcibly stopped. Therefore, for example, from the viewpoints of continuous operation of the power conversion device and planning for maintenance of the power conversion device related to the cooling structure portion, it is desirable to notify the user of the period when the operation of the power conversion device is forcibly stopped.

[0011] Therefore, in view of the above problems, a first object of the present invention in a power conversion device is to provide a technique capable of distinguishing an abnormality in the cooling performance accompanied by an abnormality in the blower portion that blows air to the cooling structure portion from an abnormality in the cooling performance accompanied by the presence of foreign matter.

[0012] In addition, in view of the above problems, the second object of the present invention is to provide a technique capable of notifying a user of the timing of forced stoppage of operation of a power conversion device accompanied by a temperature rise in a cooling structure unit.

[0013] <Method for Solving Problems>

[0014] To achieve the above first object, in one embodiment of the present invention, there is provided a power conversion device including:

[0015] A power device;

[0016] A cooling structure unit for dissipating heat of the above power device;

[0017] A blower unit that blows air to the above cooling structure unit; and

[0018] A diagnosis unit that diagnoses an abnormality related to the cooling performance based on the tendency of the time change of the temperature difference between the temperature of the above cooling structure unit and the temperature of the air inside the power conversion device.

[0019] In addition, to achieve the above first object, in another embodiment of the present invention, there is provided an information processing device related to a power conversion device, the power conversion device having:

[0020] A power device;

[0021] A cooling structure unit for dissipating heat of the above power device; and

[0022] A blower unit that blows air to the above cooling structure unit,

[0023] The information processing device diagnoses an abnormality related to the cooling performance based on the tendency of the time change of the temperature difference between the temperature of the above cooling structure unit and the temperature of the air inside the power conversion device.

[0024] In addition, to achieve the above first object, in still another embodiment of the present invention, there is provided an information processing method executed by an information processing device related to a power conversion device, the power conversion device having:

[0025] A power device;

[0026] A cooling structure unit for dissipating heat of the above power device; and

[0027] A blower unit that blows air to the above cooling structure unit,

[0028] The information processing method diagnoses an abnormality related to the cooling performance based on the tendency of the temporal change of the temperature difference between the temperature of the cooling structure unit and the temperature of the air inside the power conversion device.

[0029] Further, in order to achieve the above second object, in a further another embodiment of the present invention, there is provided a power conversion device including:

[0030] A power device;

[0031] A cooling structure unit for dissipating heat of the power device;

[0032] A blowing unit for blowing air to the cooling structure unit;

[0033] A stop control unit that forcibly stops the operation of the power conversion device after the temperature of the cooling structure unit reaches a specified reference; and

[0034] An estimation unit that estimates the possible operation time of the power conversion device until the temperature of the cooling structure unit reaches the specified reference based on the tendency of the temporal change of the temperature of the cooling structure unit.

[0035] Further, in order to achieve the above second object, in a further another embodiment of the present invention, there is provided an information processing device related to a power conversion device, the power conversion device having:

[0036] A power device;

[0037] A cooling structure unit for dissipating heat of the power device; and

[0038] A blowing unit for blowing air to the cooling structure unit,

[0039] The power conversion device forcibly stops the operation after the temperature of the cooling structure unit reaches a specified reference,

[0040] The information processing device estimates the possible operation time of the power conversion device until the temperature of the cooling structure unit reaches the specified reference based on the tendency of the temporal change of the temperature of the cooling structure unit.

[0041] Further, in order to achieve the above second object, in a further another embodiment of the present invention, there is provided an information processing method executed by an information processing device related to a power conversion device, the power conversion device having:

[0042] A power device;

[0043] A cooling structure unit for dissipating heat of the power device; and

[0044] A blower unit that blows air to the cooling structure unit.

[0045] After the temperature of the cooling structure unit reaches a specified reference, the power conversion device forcibly stops operating.

[0046] Based on the tendency of the time change of the temperature of the cooling structure unit, this information processing method estimates the possible operating time of the power conversion device until the temperature of the cooling structure unit reaches the specified reference.

[0047] <Effects of the Invention>

[0048] According to the above-described embodiment, in the power conversion device, it is possible to distinguish an abnormality in cooling performance accompanying an abnormality in the blower unit that blows air to the cooling structure unit from an abnormality in cooling performance accompanying the presence of foreign matter.

[0049] In addition, according to the above-described embodiment, it is possible to notify the user of the period of forced stop of the power conversion device accompanying the temperature rise of the cooling structure unit. Description of the Drawings

[0050] Figure 1 It is a diagram showing an example of the configuration of a cooling abnormality diagnosis system.

[0051] Figure 2 It is a schematic diagram showing an example of the cooling structure unit of the power conversion device.

[0052] Figure 3 It is a block diagram showing an example of the hardware configuration of the control device.

[0053] Figure 4 It is a block diagram showing an example of the functional configuration of the control device.

[0054] Figure 5 It is a diagram showing an example of a method for estimating a reference value (reference possible operating time) of the possible operating time from the state where maintenance related to the cooling structure unit is completed until the forced stop of the power conversion device.

[0055] Figure 6 It is a flowchart schematically showing an example of the estimation process of the reference possible operating time.

[0056] Figure 7 It is a flowchart schematically showing an example of the notification process of the remaining possible operating time until the forced stop of the power conversion device.

[0057] Figure 8 It is a diagram showing an example of the relationship between the cumulative operating time from the state where maintenance related to the cooling structure unit is completed and the notification content of the remaining possible operating time.

[0058] Figure 9 It is a block diagram showing another example of the functional configuration of the control device.

[0059] Figure 10 It is a diagram showing an example of the time change of the temperature difference between the heat sink temperature and the internal gas temperature when a cooling abnormality occurs in the power conversion device.

[0060] Figure 11 It is a diagram schematically showing an example of a method for diagnosing a cooling abnormality in a power conversion device.

[0061] Figure 12 It is a flowchart schematically showing an example of a process for obtaining reference data of the temperature difference between the heat sink temperature and the internal gas temperature.

[0062] Figure 13 It is a flowchart schematically showing an example of a diagnostic process for a cooling abnormality in a power conversion device.

[0063] Figure 14 It is a flowchart schematically showing another example of a diagnostic process for a cooling abnormality in a power conversion device.

[0064] Figure 15 It is a flowchart schematically showing another example of a notification process for the remaining operable time until forced stop of the power conversion device.

[0065] Figure 16 It is a diagram showing another example of the relationship between the cumulative operation time and the notification content of the remaining operable time from the state where maintenance related to the cooling structure part is completed.

[0066] Description of Reference Numerals

[0067] 1 Cooling Abnormality Diagnosis System

[0068] 100 Power Conversion Device

[0069] 110 Rectifier Circuit

[0070] 110A Circuit Board

[0071] 120 Smoothing Circuit

[0072] 130 Inverter Circuit

[0073] 130A Circuit Board

[0074] 140 Control Device (Information Processing Device)

[0075] 141 CPU

[0076] 142 Memory Device

[0077] 143 Auxiliary storage device

[0078] 144 Interface

[0079] 150 Sensor

[0080] 160 Display device (notification unit)

[0081] 170 Communication device (notification unit)

[0082] 180 Cooling fan

[0083] 190 Cooling structure unit

[0084] 192 Heat sink base

[0085] 194 Cooling heat sink unit

[0086] 194A Heat sink

[0087] 200 Arithmetic unit (information processing device)

[0088] 300 Terminal device (information processing device)

[0089] 310 Display unit

[0090] 1401 Drive control unit (stop control unit)

[0091] 1402 Recording unit

[0092] 1403 Storage unit

[0093] 1404 Maintenance determination unit

[0094] 1405 Operable time estimation unit (estimation unit)

[0095] 1406 Diagnosis unit

[0096] M Electric motor

[0097] NL Negative electrode wire

[0098] PL Positive electrode wire

[0099] PS Commercial power supply

[0100] SD Semiconductor diode (power device)

[0101] SW Semiconductor switch (power device) Detailed implementation manners

[0102] Hereinafter, the embodiments will be described with reference to the drawings.

[0103] [Configuration of cooling abnormality diagnosis system]

[0104] Refer to Figure 1 , and the configuration of the cooling abnormality diagnosis system 1 of the present embodiment will be described.

[0105] Figure 1 It is a diagram showing an example of the configuration of the cooling abnormality diagnosis system 1 of the present embodiment.

[0106] The cooling abnormality diagnosis system 1 of the present embodiment is used to perform diagnosis related to abnormalities in the cooling performance of the power conversion device 100.

[0107] As Figure 1 shown, the cooling abnormality diagnosis system 1 includes a power conversion device 100, an arithmetic device 200, and a terminal device 300.

[0108] The power conversion device 100 converts three-phase alternating current (for example, R-phase, S-phase, and T-phase) input from a commercial power supply PS into three-phase alternating current (for example, U-phase, V-phase, and W-phase) having a specified voltage and a specified frequency, thereby driving the motor M.

[0109] The motor M is electrically driven based on the three-phase AC power output from the power conversion device 100 to a specified machine such as a winding machine provided in a textile factory.

[0110] It should be noted that the power conversion device 100 can generate three-phase alternating current for driving the motor M based on three-phase alternating current input from a power source other than the commercial power supply. In addition, the power conversion device 100 can generate three-phase alternating current for driving the motor M based on the power input from a DC power source. In this case, direct current is input to the DC connection part (positive line PL and negative line NL) between the following rectifier circuit 110 and inverter circuit 130.

[0111] The power conversion device 100 includes a rectifier circuit 110, a smoothing circuit 120, an inverter circuit 130, a control device 140, a sensor 150, a display device 160, a communication device 170, and a cooling fan 180.

[0112] The rectifier circuit 110 is configured to rectify the three-phase alternating current of the R-phase, S-phase, and T-phase input from the commercial power supply PS, so as to be able to output direct current. The positive and negative output terminals of the rectifier circuit 110 are respectively connected to one ends of the positive line PL and the negative line NL, so as to be able to output direct current to the smoothing circuit 120 through the positive line PL and the negative line NL. The rectifier circuit 110 is, for example, a bridge full-wave rectifier circuit including six semiconductor diodes SD (an example of a power device) (refer to Figure 2 ), and three groups of series-connected bodies of two semiconductor diodes SD constituting the upper and lower bridge arms are connected in parallel.

[0113] The smoothing circuit 120 is used to suppress the pulsation of the direct current output from the self-rectifying circuit 110 and the direct current regenerated from the self-inverter circuit 130 and smooth it.

[0114] The smoothing circuit 120 includes, for example, a smoothing capacitor.

[0115] The smoothing capacitor can be provided in parallel with the rectifying circuit 110 and the inverter circuit 130 in the path connecting the positive line PL and the negative line NL.

[0116] The smoothing capacitor appropriately repeats charging and discharging, thereby smoothing the direct current output from the self-rectifying circuit 110 and the direct current output (regenerated) from the self-inverter circuit 130.

[0117] There can be one smoothing capacitor. In addition, multiple smoothing capacitors can be provided. The multiple smoothing capacitors can be connected in parallel or in series between the positive line PL and the negative line NL. In addition, multiple smoothing capacitors can be configured in such a way that a series connection body of two or more smoothing capacitors is connected in parallel between the positive line PL and the negative line NL.

[0118] In addition, the smoothing circuit 120 includes, for example, a reactor.

[0119] The reactor can be provided on the positive line PL between the rectifying circuit 110 and the smoothing capacitor (specifically, the branch point of the path where the smoothing capacitor is arranged).

[0120] The reactor appropriately generates a voltage in a manner that impedes the change in current while smoothing the direct current output from the self-rectifying circuit 110 and the direct current output (regenerated) from the self-inverter circuit 130.

[0121] The positive and negative input terminals of the inverter circuit 130 are connected to the other ends of the positive line PL and the negative line NL. The inverter circuit 130 converts the direct current supplied from the smoothing circuit 120 into three-phase alternating current (for example, U-phase, V-phase, and W-phase) with a specified frequency and a specified voltage through the switching operation of a semiconductor switch SW (an example of a power device) (refer to Figure 2 ) and outputs it to the motor M. The semiconductor switch can be, for example, an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) made of silicon (Si). In addition, the semiconductor switch can be a semiconductor element using a wide-bandgap semiconductor such as silicon carbide (SiC) or gallium nitride (GaN).

[0122] The inverter circuit 130 is configured, for example, to include a bridge circuit, the bridge circuit including six semiconductor switches SW, and three series-connected bodies (switch legs) each formed by two semiconductor switches constituting an upper and a lower bridge arm are connected in parallel between a positive line PL and a negative line NL. Further, the inverter circuit 130 can output three-phase alternating current through a U-phase line, a V-phase line, and a W-phase line led out from connection points of the three upper and lower bridge arms. Additionally, freewheeling diodes can be respectively connected in parallel with the six semiconductor switches.

[0123] The control device 140 (an example of an information processing device) performs control related to the power conversion device 100. The functions of the control device 140 can be implemented by any hardware or any combination of hardware and software, etc.

[0124] It should be noted that part or all of the functions of the control device 140 can be transferred outside the power conversion device 100, for example, to an arithmetic device 200, a terminal device 300 (both examples of information processing devices), etc.

[0125] The sensor 150 is used to obtain detection data related to the operating state (working state) of the power conversion device 100. The sensor 150 is connected to the control device 140, for example, through a one-to-one communication line, etc., and a signal corresponding to the detection data is introduced into the control device 140. Thereby, the control device 140 can perform control related to the power conversion device 100 based on the detection signal of the sensor 150, or as described later, perform diagnosis related to a cooling abnormality of the power conversion device 100, or calculate the possible operating time until the power conversion device 100 is forced to stop operating.

[0126] The sensor 150 includes, for example, various temperature sensors. The temperature sensors can include, for example, a fin temperature sensor for detecting the temperature of the cooling fin portion 194 (hereinafter referred to as "fin temperature") Tf. Additionally, the temperature sensors can include, for example, an internal gas temperature sensor for detecting the temperature of the air inside the housing of the power conversion device 100 (hereinafter referred to as "internal gas temperature") Ta.

[0127] Further, the sensor 150 includes, for example, various current sensors, voltage sensors, etc. The current sensors can include, for example, a load current sensor for detecting the load current output to the motor M.

[0128] The display device 160 (an example of a notification unit) is provided, for example, on the outer surface of the housing of the power conversion device 100. The display device 160 displays information related to the operating state (working state) of the power conversion device 100 under the control of the control device 140.

[0129] Note that the display device 160 can be provided outside the housing of the power conversion device 100, for example, on the surface (outer surface) of a housing of a prescribed machine that is electrically driven by the electric motor M.

[0130] The communication device 170 (an example of the notification unit) communicates with external devices of the power conversion device 100, such as the arithmetic device 200 and the terminal device 300, via a prescribed communication line.

[0131] The prescribed communication line can be, for example, a one-to-one communication line. Additionally, the prescribed communication line can include, for example, a local area network (LAN) such as a field network constructed within a facility (factory) where the machine electrically driven by the electric motor M is installed. The local area network can be constructed by wire, by wireless, or can include both. Further, the prescribed communication line can include, for example, a wide area network (WAN) outside the facility (factory) where the machine electrically driven by the electric motor M is installed. The wide area network can include, for example, a mobile body communication network with a base station at the end, a satellite communication network using communication satellites, and the Internet. Additionally, the prescribed communication line can include a short-range communication line based on a prescribed wireless communication standard such as Bluetooth (registered trademark) and WiFi.

[0132] Note that the function of the communication device 170 can be incorporated into the control device 140 (interface 144).

[0133] The cooling fan 180 (an example of the air supply unit) supplies air to the cooling structure unit 190 described later (specifically, the cooling fin unit 194), promoting heat dissipation through the cooling structure unit 190.

[0134] An intake port (suction port) for external gas and an exhaust port for internal gas are provided in the housing of the power conversion device 100. The cooling fan 180 can be provided on the upstream side of the cooling structure unit 190 in the path of the air flow from the intake port toward the exhaust port. In this case, the cooling fan 180 sucks in external gas from the intake port and sends it toward the cooling structure unit 190, causing the relatively lower-temperature external gas to come into contact with the cooling structure unit 190. Through heat exchange with the cooling structure unit 190, the heated air is discharged from the exhaust port. Additionally, the cooling fan 180 can be provided on the downstream side of the cooling structure unit 190 in the path of the air flow from the intake port toward the exhaust port. In this case, the cooling fan 180 sucks out the air around the cooling structure unit 190, creating an air flow from the upstream intake port toward the cooling structure unit 190, thereby causing the relatively lower-temperature external gas to come into contact with the cooling structure unit 190.

[0135] The arithmetic unit 200 is provided outside the power conversion device 100 and is used for performing various arithmetic processes.

[0136] The arithmetic unit 200 is connected, for example, in a manner capable of communicating with the power conversion device 100 through a prescribed communication line, and it can perform arithmetic processes related to the control of the power conversion device 100 according to an instruction from the control device 140. Specifically, the arithmetic unit 200 can perform part or all of the arithmetic processes related to the determination of cooling anomalies described later according to an instruction from the control device 140.

[0137] The arithmetic unit 200 can be, for example, a PLC (Programmable Logic Controller) or an edge processor for controlling a prescribed machine electrically driven by the motor M. Additionally, the arithmetic unit 200 can be a computer terminal such as a PC (Personal Computer), for example.

[0138] Furthermore, the arithmetic unit 200 can be a server device, for example. The server device can be an on-premises server outside the facility (factory) where a prescribed machine electrically driven by the motor M is installed, or a cloud server. Additionally, the server device can be an edge server installed inside the facility (factory) where a prescribed machine electrically driven by the motor M is installed, or installed in a communication facility (such as a base station, office) adjacent to the facility, for example.

[0139] The terminal device 300 is provided outside the power conversion device 100 and is used by the user of the power conversion device 100 (cooling anomaly diagnosis system 1). The terminal device 300 provides various information to the user through the display unit 310, for example, or receives various inputs from the user and sends them to the power conversion device 100.

[0140] The terminal device 300 can include, for example, a fixed terminal device such as a desktop computer terminal. Additionally, the terminal device 300 can include a portable (mobile) terminal device (portable terminal) such as a smartphone, a tablet terminal, or a laptop computer terminal, for example.

[0141] [Cooling Structure of Power Conversion Device]

[0142] Next, with reference to Figure 2 , the cooling structure portion 190 of the power conversion device 100 will be described.

[0143] Figure 2 is a schematic diagram showing an example of the cooling structure portion 190 of the power conversion device 100.

[0144] The cooling structure part 190 is equivalent to, for example, a radiator, and includes a fin base 192 and a cooling fin part 194.

[0145] The fin base 192 has a flat plate shape with a prescribed thickness. One surface (the lower surface in the figure) of the flat plate shape of the fin base 192 is provided with the cooling fin part 194, and circuit boards 110A and 130A corresponding to the rectifier circuit 110 and the inverter circuit 130 are placed on the other surface (the upper surface in the figure).

[0146] The fin base 192 is made of a component with relatively high thermal conductivity. Thereby, the heat energy generated by the losses during energization of the semiconductor diode SD and the semiconductor switch SW can be easily conducted to the fin base 192. Here, materials with relatively high thermal conductivity refer to, for example, metals such as aluminum, iron, and copper. The same applies to the cooling fin part 194.

[0147] As described above, the cooling fin part 194 is provided on one surface of the flat plate shape of the fin base 192. The cooling fin part 194 includes a plurality of fins 194A provided so as to protrude in a direction away from the surface of the fin base 192 (in the negative Z-axis direction in the figure).

[0148] The plurality of fins 194A each have a very thin flat plate shape and are arranged at substantially equal intervals in a prescribed direction (the X-axis direction in the figure) on one surface of the fin base 192.

[0149] The plurality of fins 194A are each made of a component with relatively high thermal conductivity. Thereby, the heat energy generated by the losses during energization of the semiconductor diode SD and the semiconductor switch SW can be easily conducted from the fin base 192 to the plurality of fins 194A. In addition, the plurality of fins 194A have a relatively large surface area. Thereby, the contact area between the plurality of fins 194A and the air can be made relatively large, so that the heat energy can be easily dissipated to the surrounding air. Therefore, the heat energy generated by the losses during energization of the semiconductor diode SD and the semiconductor switch SW can be easily dissipated to the air, and the cooling performance of the power conversion device 100 can be improved.

[0150] In addition, under the action of the cooling fan 180, the cooling air CA flows in a direction (Y-axis direction in the figure) perpendicular to the direction (X-axis direction) in which the plurality of heat sinks 194A are arranged. As a result, the cooling air CA passes between the plurality of heat sinks 194A, and the temperature of the air around the plurality of heat sinks 194A is maintained at a relatively low level. Therefore, the temperature difference between the heat sink 194A and the surrounding air becomes relatively large, and the heat energy of the heat sink 194A can be easily dissipated to the surrounding air. Therefore, the heat energy generated due to the conduction losses of the semiconductor diode SD and the semiconductor switch SW is easily dissipated to the air, further improving the cooling performance of the power conversion device 100, thereby ensuring the cooling performance required by the power conversion device 100.

[0151] On the other hand, depending on the environment in which the power conversion device 100 is installed, foreign objects may be blocked between the plurality of heat sinks 194A. In addition, depending on the size of the foreign object, the foreign object may also block the air inlet of the housing of the power conversion device 100. For example, in a textile factory, not only does the air contain dust, but sometimes it also contains cotton, and there is a possibility that cotton and the like block between the plurality of heat sinks 194A and the air inlet of the housing of the power conversion device 100. As a result, there is a possibility that the cooling air CA does not contact the heat sink 194A corresponding to the part blocked by the foreign object, or the amount of external gas inhaled from the air inlet becomes smaller and the temperature of the air supplied to the cooling heat sink part 194 becomes higher. Therefore, the cooling performance of the semiconductor diode SD and the semiconductor switch SW based on the cooling structure part 190 and the cooling fan 180 deteriorates. As a result, an abnormality in the cooling performance of the power conversion device 100 (semiconductor diode SD and semiconductor switch SW) based on the cooling structure part 190 and the cooling fan 180 (hereinafter referred to as "cooling abnormality") may occur.

[0152] In addition, if the cooling fan 180 malfunctions, the rotational speed of the cooling fan 180 decreases, or the cooling fan 180 stops, the temperature of the air around the cooling heat sink part 194 (heat sink 194A) becomes relatively high. Therefore, the cooling performance of the semiconductor diode SD and the semiconductor switch SW based on the cooling structure part 190 and the cooling fan 180 deteriorates. As a result, a cooling abnormality of the power conversion device 100 (semiconductor diode SD and semiconductor switch SW) based on the cooling structure part 190 and the cooling fan 180 may occur.

[0153] Moreover, depending on the degree of the cooling abnormality, it is possible that the heat sink temperature Tf reaches the overheat temperature Tferr, and as a result, it becomes necessary to forcibly stop the power conversion device 100, which affects the operation of the factory where the specified machinery electrically driven by the motor M is installed.

[0154] It should be noted that the cooling structure portion 190 only needs to be able to promote the dissipation of heat energy generated due to the losses during the energization of the semiconductor diode SD and the semiconductor switch SW to the surrounding air, and it can be in any form. For example, there can be multiple heat sinks 194A, or there can be one. Additionally, on the heat sink base 192, one or more rod-shaped or needle-shaped protrusions made of components with relatively high thermal conductivity can be provided instead of the heat sink 194A.

[0155] [An example of the configuration of the control device]

[0156] Next, with reference to Figure 3 、 Figure 4 , an example of the configuration of the control device 140 will be described.

[0157] Figure 3 、 Figure 4 is a diagram showing an example of the configuration of the control device 140 of the cooling abnormality diagnosis system 1 of the present embodiment. Specifically, Figure 3 is a block diagram showing an example of the hardware configuration of the control device 140, Figure 4 is a block diagram showing an example of the functional configuration of the control device 140.

[0158] As Figure 3 shown, the control device 140 includes, for example, a CPU 141 (Central Processing Unit), a memory device 142 such as a RAM (Random Access Memory), an auxiliary storage device 143 such as a ROM (Read Only Memory), and an interface 144, which are connected to each other via a bus B. The control device 140 performs various controls by loading the program installed in the auxiliary storage device 143 into the memory device 142 and causing the CPU 141 to execute it. Additionally, the control device 140 receives external signals or outputs (sends) signals to the outside through the interface 144.

[0159] As Figure 4 shown, the control device 140 includes, as functional parts, a drive control part 1401, a recording part 1402, a storage part 1403, a maintenance determination part 1404, and an operable time estimation part 1405. The functions of the drive control part 1401, the recording part 1402, the maintenance determination part 1404, and the operable time estimation part 1405 are realized, for example, by loading the program installed in the auxiliary storage device 143 into the memory device 142 and executing it on the CPU 141. Additionally, the function of the storage part 1403 is realized, for example, by a storage area specified in the auxiliary storage device 143.

[0160] The drive control unit 1401 controls the drive of the motor M through the inverter circuit 130. Specifically, the drive control unit 1401 outputs drive signals to the inverter circuit 130 (specifically, the gates of the respective semiconductor switches SW), and uses the inverter circuit 130 to drive the motor M in such a manner that the motor M satisfies the specified operating conditions. In other words, the drive control unit 1401 generates a control signal for driving the motor M according to the specified operating conditions and outputs it to the inverter circuit 130.

[0161] In addition, for the drive control unit 1401 (an example of a stop control unit), when the heat sink temperature Tf reaches the overheat temperature Tferr indicating the overheated state of the heat sink unit 194 for cooling, the protection function of the power conversion device 100 is activated, thereby forcibly stopping the operation of the power conversion device 100.

[0162] The recording unit 1402 records the specified measurement data imported from the sensor 150 in the storage unit 1403 in time series. The details of the recording unit 1402 will be described later (refer to Figure 6 , 7 , Figure 12 ).

[0163] The storage unit 1403 is used to store the specified measurement data recorded in time series by the recording unit 1402. For example, recording data including the specified measurement data and the time data at the time of obtaining the measurement data can be stored in the storage unit 1403.

[0164] The maintenance determination unit 1404 determines whether maintenance related to the cooling structure unit 190 has been performed. Maintenance related to the cooling structure unit 190 means maintaining the function of the cooling structure unit 190, that is, the cooling function of the power conversion device 100 based on the cooling structure unit 190, in a normal state. Maintenance related to the cooling structure unit 190 includes, for example, cleaning of the cooling structure unit 190 (the heat sink unit 194), the intake port of the housing of the power conversion device 100, and the like.

[0165] For example, the maintenance determination unit 1404 can determine that maintenance of the cooling structure unit 190 has been performed when it receives a specified input from the user indicating that maintenance related to the cooling structure unit 190 has been performed. The specified input from the user is received, for example, through an input unit provided in the power conversion device 100 or a specified machine on which the power conversion device 100 is mounted. In addition, the specified input from the user is received, for example, when a signal indicating the user's specified input to the input unit provided in the arithmetic device 200 or the terminal device 300 is sent from the arithmetic device 200 or the terminal device 300 and received by the communication device 170.

[0166] In addition, for example, the maintenance determination unit 1404 determines whether maintenance of the cooling structure unit 190 has been performed by comparing the measurement data of the sensor 150 during the operation of the power conversion device 100 last time and this time. Specifically, the maintenance determination unit 1404 can compare the measurement data of the temperature (heat sink temperature Tf) of the cooling heat sink unit 194 during the operation of the power conversion device 100 last time and this time, or its change over time, to determine whether maintenance of the cooling structure unit 190 has been performed. This is because if maintenance (cleaning) of the cooling structure unit 190 is performed, the heat dissipation efficiency of the cooling structure unit 190 is improved, and the heat sink temperature Tf or its change over time may be different from that during the operation of the power conversion device 100 last time. In addition, the maintenance determination unit 1404 can compare the measurement data of the temperature (internal gas temperature Ta) of the air inside the housing of the power conversion device 100 during the operation of the power conversion device 100 last time and this time, or its change over time, to determine whether maintenance of the cooling structure unit 190 has been performed. This is because if maintenance of the cooling structure unit 190 is performed, as described above, the heat dissipation efficiency of the cooling structure unit 190 is improved, and the temperature (internal gas temperature Ta) of the air, which is the heat transfer location of the thermal energy of the cooling structure unit 190, and its change over time may be different from that during the operation of the power conversion device 100 last time. In addition, the maintenance determination unit 1404 can compare the measurement data of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta during the operation of the power conversion device 100 last time and this time, or its change over time, to determine whether maintenance of the cooling structure unit 190 has been performed. This is because if maintenance of the cooling structure unit 190 is performed, as described above, the heat dissipation efficiency of the cooling structure unit 190 is improved, and the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta and its change over time may be different from that during the operation of the power conversion device 100 last time.

[0167] The operation possible time estimation unit 1405 (an example of an estimation unit) estimates the operation possible time of the power conversion device 100 until the temperature (heat sink temperature Tf) of the cooling structure unit 190 (cooling heat sink unit 194) reaches the overheat temperature Tferr and is forced to stop. The detailed content of the operation possible time estimation unit 1405 will be described later (see Figure 5 , Figure 7 ).

[0168] [Outline of the method for estimating the operation possible time]

[0169] Next, with reference to Figure 5 , an outline of the method for estimating the operation possible time of the power conversion device 100 until the heat sink temperature Tf reaches the overheat temperature Tferr by the control device 140 will be described.

[0170] Figure 5This is a diagram showing an example of a method for estimating a reference value (hereinafter referred to as "reference operable time") OTcr of the operable time from the state where maintenance related to the cooling structure portion 190 is completed until forced stop of the power conversion device 100.

[0171] The reference operable time OTcr is a reference value of the operable time of the power conversion device 100 from the state where maintenance related to the cooling structure portion 190 is completed until forced stop due to an increase in the heat sink temperature Tf caused by the presence of foreign matter such as blockage of the intake port of the cooling heat sink portion 194 and the housing.

[0172] The control device 140 (recording unit 1402) starts from the start of use of the power conversion device 100 after factory shipment, and records the measurement data of the heat sink temperature Tf in the range where the heat sink temperature Tf is somewhat lower than the overheat temperature Tferr in time series in the storage unit 1403. For example, the recording unit 1402 records the measurement data of the heat sink temperature Tf in time series in the storage unit 1403 during the period from the start of use of the power conversion device 100 after factory shipment until the heat sink temperature Tf reaches a specified temperature (hereinafter referred to as "recording end temperature") Tfover corresponding to the end condition. The recording end temperature Tfover is set to a temperature somewhat lower (lower) than the overheat temperature Tferr. Thus, as Figure 5 shown, the control device 140 can obtain reference data (hereinafter, for convenience, referred to as "reference data of the heat sink temperature Tf") 501 indicating the tendency of the change in the heat sink temperature Tf with the passage of the cumulative operation time OT starting from the start of use of the power conversion device 100 after factory shipment.

[0173] Furthermore, the control device 140 (operable time estimation unit 1405) uses the obtained reference data 501 of the heat sink temperature Tf, and extrapolates the timing 502 at which the heat sink temperature Tf reaches the overheat temperature in the case of a change in the heat sink temperature Tf according to the tendency of the reference data 501. Specifically, the recording unit 1402 starts from the start of use of the power conversion device 100 after factory shipment, which corresponds to the state where maintenance related to the cooling structure portion 190 is completed, and estimates the reference operable time OTcr until forced stop of the power conversion device 100 by extrapolation. At this time, for example, known extrapolation methods such as linear extrapolation, polynomial extrapolation, and least squares method can be applied. Thus, after obtaining the reference operable time OTcr, the operable time estimation unit 1405 can estimate the remaining operable time OTrem of the power conversion device 100 until forced stop due to an increase in the heat sink temperature Tf based on the reference operable time OTcr.

[0174] Specifically, if the operation possible time estimation unit 1405 determines through the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has been performed, it measures the cumulative operation time OTa of the power conversion device 100 starting from the state where the maintenance related to the cooling structure unit 190 is completed. Then, the operation possible time estimation unit 1405 subtracts the cumulative operation time OTa of the power conversion device 100 from the reference operation possible time OTcr to estimate the remaining operation possible time OTrem of the power conversion device 100 (OTrem = OTcr - OTa).

[0175] It should be noted that the operation possible time estimation unit 1405 can estimate the remaining operation possible time OTrem of the power conversion device 100 in a simpler method without obtaining the reference data of the heat sink temperature Tf. For example, the operation possible time estimation unit 1405 can estimate the remaining operation possible time OTrem by extrapolation based on the past history of the measurement data of the heat sink temperature Tf starting from the most recent moment when the maintenance determination unit 1404 determines that maintenance related to the cooling structure unit 190 has been performed.

[0176] [Estimation Process of Reference Operation Possible Time]

[0177] Next, with reference to Figure 6 , the estimation process of the reference operation possible time OTcr based on the control device 140 will be described.

[0178] Figure 6 is a flowchart schematically showing an example of the estimation process of the reference operation possible time OTcr performed by the control device 140. This flowchart is repeatedly executed for each specified cycle, for example, during the operation of the power conversion device 100 from power-on to power-off.

[0179] In this example, a flag F1 indicating the acquisition of the reference operation possible time OTcr is used. The flag F1 is stored in the auxiliary storage device 143, for example, and at the time of factory shipment of the power conversion device 100, as an initial value, the reference operation possible time OTcr is set to "0" indicating non-acquisition. And the flag F1 can be read from the auxiliary storage device 143 to the memory device 142 for utilization or update when the power conversion device 100 is powered on, and store the latest state in the auxiliary storage device 143 when the power conversion device 100 is powered off.

[0180] As Figure 6As shown, through step S102, the recording unit 1402 determines whether the flag F1 is "0", that is, whether the reference operating possible time OTcr is in an unacquired state. When the flag F1 is "0", the recording unit 1402 proceeds to step S104. When the flag F1 is not "0", that is, when it is "1" indicating that the reference operating possible time OTcr has been acquired, the processing of this flowchart is ended.

[0181] Through step S104, the recording unit 1402 determines whether the measurement data of the latest heat sink temperature Tf is greater than the maximum heat sink temperature Tfmax.

[0182] The maximum heat sink temperature Tfmax represents the maximum value among the measurement data of the heat sink temperature Tf recorded in the storage unit 1403. The maximum heat sink temperature Tfmax is set to a specified initial value at the time of factory shipment.

[0183] When the measurement data of the latest heat sink temperature Tf is greater than the maximum heat sink temperature Tfmax, the recording unit 1402 proceeds to step S106. Otherwise, the processing of this flowchart is ended.

[0184] Through step S106, the recording unit 1402 records the measurement data of the latest heat sink temperature Tf and the cumulative operating time OT of the power conversion device 100 since the start of use after factory shipment when this measurement data was obtained, in association with each other, in the storage unit 1403. Specifically, the recording unit 1402 creates recording data including the measurement data of the latest heat sink temperature Tf and the cumulative operating time OT when this measurement data was obtained, and saves it in the storage unit 1403.

[0185] After the processing of step S106 is completed, the control device 140 proceeds to step S108.

[0186] Through step S108, the recording unit 1402 determines whether the end condition for the recording of the measurement data of the heat sink temperature Tf in the time series, which is the reference data for the heat sink temperature Tf, is satisfied.

[0187] The end condition can be, for example, that the heat sink temperature Tf reaches the recording end temperature Tfover corresponding to the end condition. Additionally, the end condition can be, for example, that the number of times of recording the measurement data reaches a specified number of times.

[0188] When the end condition for the recording of the reference data of the heat sink temperature Tf is satisfied, the recording unit 1402 proceeds to step S110. When the end condition is not satisfied, the processing of this flowchart is ended.

[0189] Through step S110, the recording unit 1402 sets the flag F1 to "1".

[0190] After the process in step S110 is completed, the control device 140 proceeds to step S112.

[0191] Through step S112, the operation possible time estimation unit 1405 estimates the reference operation possible time OTcr by extrapolation based on the reference data of the heat sink temperature Tf stored in the storage unit 1403.

[0192] After the process in step S112 is completed, the control device 140 ends the processing of this flowchart.

[0193] In this way, the control device 140 obtains the reference data of the heat sink temperature Tf indicating the tendency of the time change of the heat sink temperature Tf starting from the state indicating the start of use of the power conversion device 100 after factory shipment, which is equivalent to the state where the maintenance related to the cooling structure unit 190 is completed. Thereby, the control device 140 can use the reference data of the heat sink temperature Tf to obtain the reference operation possible time (reference operation possible time OTcr) from the state where the maintenance related to the cooling structure unit 190 is completed until the power conversion device 100 is forcibly stopped due to the rise of the heat sink temperature Tf.

[0194] [An example of the notification process of the remaining operation possible time]

[0195] Next, with reference to Figure 7 , Figure 8 , an example of the notification process of the remaining operation possible time OTrem until the power conversion device 100 is forcibly stopped based on the control device 140 will be described.

[0196] Figure 7 is a flowchart schematically showing an example of the notification process of the remaining operation possible time OTrem until the power conversion device 100 is forcibly stopped by the control device 140. Figure 8 is a diagram showing an example of the relationship between the cumulative operation time OTa from the state where the maintenance related to the cooling structure unit 190 is completed and the notification content of the remaining operation possible time OTrem.

[0197] Figure 7 The flowchart of Figure 7 is repeatedly executed for each specified cycle during the operation of the power conversion device 100 from power-on to power-off. In addition, Figure 14 the flowchart of

[0198] As Figure 7 shown, through step S202, the operable time estimation unit 1405 determines whether the flag F1 is "1", that is, determines whether the reference operable time OTcr has been obtained. When the flag F1 is "1", the operable time estimation unit 1405 proceeds to step S204. When the flag F1 is not "1", that is, when it is "0" indicating that the reference operable time OTcr has not been obtained, the processing of this flowchart is terminated.

[0199] Through step S204, the operable time estimation unit 1405 estimates (calculates) the remaining operable time OTrem by subtracting the current cumulative operation time OTa from the reference operable time OTcr.

[0200] After the processing of step S204 is completed, the control device 140 proceeds to step S206.

[0201] Through step S206, the operable time estimation unit 1405 notifies the user of the remaining operable time OTrem estimated in step S204. Thus, the control device 140 can start from the state where the maintenance of the power conversion device 100 related to the cooling structure unit 190 is completed, and notify the user of the remaining operable time OTrem in such a way that subtraction operations are successively performed from the reference operable time OTcr as the cumulative operation time OTa elapses (see Figure 8 ).

[0202] The operable time estimation unit 1405 notifies the remaining operable time OTrem visually, for example, through the display device 160 or the display unit 310 of the terminal device 300. The visual display content indicating the remaining operable time OTrem can be, for example, text information such as numbers representing the remaining operable time OTrem, or a bar graph, etc. In addition, the operable time estimation unit 1405 can notify the remaining operable time OTrem by an auditory method, that is, sound information, through a sound output unit provided in the power conversion device 100 or a specified machine mounted on the power conversion device 100.

[0203] After the processing of step S206 is completed, the control device 140 terminates the processing of this flowchart.

[0204] In this way, in this example, the control device 140 estimates the remaining operable time OTrem until the forced stop of the power conversion device 100 based on the time-series measurement data of the actual heat sink temperature Tf.

[0205] Accordingly, the control device 140 can notify the user of the period of forced stop of the power conversion device 100 based on the remaining available operation time OTrem until the forced stop of the power conversion device 100. Therefore, the user can more easily perform operations based on the continuous operation of the power conversion device 100, planning for maintenance of the power conversion device 100 related to the cooling structure unit 190, etc.

[0206] In addition, in this example, the control device 140 notifies the remaining available operation time OTrem until the forced stop of the power conversion device 100 estimated through the display device 160 and the communication device 170 due to the rise in the heat sink temperature Tf. Specifically, the control device 140 notifies the remaining available operation time OTrem through the display device 160 and the communication device 170 in a manner of subtracting according to the passage of time starting from the state where the maintenance related to the cooling structure unit 190 is completed.

[0207] Accordingly, the control device 140 can notify the user of the remaining available operation time OTrem that is successively subtracted starting from the state where the maintenance related to the cooling structure unit 190 is completed.

[0208] [Another example of the configuration of the control device]

[0209] Next, with reference to Figure 9 , another example of the configuration of the control device 140 will be described. Hereinafter, the description will focus on the parts different from the above-mentioned one example ( Figure 3 , Figure 4 ), and the description of the same or corresponding content as the above-mentioned one example may be omitted.

[0210] Figure 9 is a block diagram showing another example of the functional configuration of the control device 140.

[0211] It should be noted that in this example, the hardware configuration of the control device 140 is the same as that of the above-mentioned one example. Therefore, referring to the above-mentioned one example ( Figure 3 ), the illustration is omitted.

[0212] As shown in Figure 9As shown, similar to the case of the above example, the control device 140 includes, as functional units, a drive control unit 1401, a recording unit 1402, a storage unit 1403, a maintenance determination unit 1404, and an operable time estimation unit 1405. Additionally, different from the above example, the control device 140 has a diagnosis unit 1406. The functions of the drive control unit 1401, the recording unit 1402, the maintenance determination unit 1404, the operable time estimation unit 1405, and the diagnosis unit 1406 are realized, for example, by loading a program installed in the auxiliary storage device 143 into the memory device 142 and executing it on the CPU 141. Additionally, the function of the storage unit 1403 is realized, for example, by a storage area defined in the auxiliary storage device 143.

[0213] The diagnosis unit 1406 performs a diagnosis related to an abnormality in the cooling performance of the power conversion device 100. Specifically, it performs a diagnosis related to an abnormality in the cooling performance of the cooling fan 180, which is used to supply cooling air to the cooling structure unit 190 that dissipates heat generated by the losses during the energization of the semiconductor diode SD and the semiconductor switch SW described later. Details will be described later (refer to Figure 11 , Figure 13 ).

[0214] [Outline of the cooling abnormality diagnosis method]

[0215] Next, with reference to Figure 10 , Figure 11 , an outline of the diagnosis method related to the cooling abnormality of the power conversion device 100 based on the control device 140 (diagnosis unit 1406) will be described.

[0216] Figure 10 is a diagram showing an example of the time change of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta when a cooling abnormality occurs. Specifically, Figure 10 is a diagram showing an example of the time change of the temperature difference Y (curve graph 1001) when a cooling abnormality occurs due to the presence of a foreign object, and an example of the time change of the temperature difference Y (curve graph 1002) when a cooling abnormality occurs due to an abnormality (failure) of the cooling fan 180. Figure 11 is a diagram schematically showing an example of the diagnosis method for the cooling abnormality of the power conversion device 100.

[0217] As shown in Figure 10As shown, if cooling anomalies occur, then as time passes, the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta increases. This is because the heat dissipation rate from the self-cooling structure 190 to the air decreases, the rate of increase of the heat sink temperature Tf with respect to time change becomes relatively larger, while on the other hand, the rate of increase of the internal gas temperature Ta with respect to time change becomes relatively smaller. Therefore, the diagnostic unit 1406 can determine the presence or absence of cooling anomalies based on the magnitude of the measured data of the temperature difference Y and the tendency of the time change.

[0218] In addition, when cooling anomalies occur due to the presence of foreign objects, the rate of increase of the temperature difference Y is relatively small (slow), while on the other hand, when cooling anomalies occur due to anomalies in the cooling fan 180, the rate of increase of the temperature difference Y becomes relatively larger. Therefore, the diagnostic unit 1406 can distinguish between anomalies in cooling performance due to the presence of foreign objects and anomalies in cooling performance due to anomalies in the cooling fan 180 based on the magnitude of the rate of increase of the temperature difference Y.

[0219] For example, as Figure 11 shown, the diagnostic unit 1406 uses reference data (hereinafter, for convenience, referred to as "reference data of the temperature difference Y") 1100 indicating the tendency of the time change of the temperature difference Y when there are anomalies in cooling performance due to the presence of foreign objects, and while distinguishing between cooling anomalies due to the presence of foreign objects and cooling anomalies due to anomalies in the cooling fan 180, determines the presence or absence of cooling anomalies.

[0220] The reference data 1100 shows the time change of the temperature difference Y over the cumulative operating time OTa of the power conversion device 100 in a state where maintenance related to the self-cooling structure 190 is completed when there are anomalies in cooling performance due to the presence of foreign objects. The cumulative operating time OTa of the power conversion device 100 in a state where maintenance related to the self-cooling structure 190 is completed is the cumulative operating time of the power conversion device 100 starting from the state after maintenance related to the self-cooling structure 190 is performed. The control device 140 can calculate the cumulative operating time OTa by subtracting the cumulative operating time OT before maintenance related to the self-cooling structure 190 from the cumulative operating time OT starting from the start of use after shipping from the factory.

[0221] When the deviation of the measured data of the temperature difference Y from the reference data 1100 of the temperature difference Y is relatively small or smaller than the first threshold, it is determined that there is an abnormality in the cooling performance accompanied by the presence of foreign matter. Specifically, the diagnosis unit 1406 can determine that there is an abnormality in the cooling performance accompanied by the presence of foreign matter when the coordinates specified by the measured data of the temperature difference Y and the cumulative operation time OTa in the self-maintenance completed state at the time of obtaining the measured data are within the area 1101 including the reference data 1100 of the temperature difference Y. More specifically, the diagnosis unit 1406 can determine that there is an abnormality in the cooling performance accompanied by the presence of foreign matter when the difference between the measured data of the temperature difference Y and the reference value Ycr at the same timing starting from the state where maintenance related to the cooling structure unit 190 is completed is smaller than the threshold value ΔYth (>0). For example, the area 1101 is set to a range of ±30% of the value of the reference data 1100 of the temperature difference Y (hereinafter referred to as "reference value") Ycr. In this case, the threshold value ΔYth corresponds to 30% of the reference value Ycr at the same timing as when the measured data of the temperature difference Y is obtained, starting from the state where maintenance related to the cooling structure unit 190 is completed.

[0222] On the other hand, when the deviation of the measured data of the temperature difference Y from the reference data 1100 of the temperature difference Y is relatively large or larger than the second threshold in the direction of increasing the temperature difference Y, it is determined that there is an abnormality in the cooling performance accompanied by an abnormality in the cooling fan 180. Specifically, the diagnosis unit 1406 can determine that there is an abnormal cooling accompanied by an abnormality in the cooling fan 180 when the coordinates specified by the measured data of the temperature difference Y and the cumulative operation time OTa in the self-maintenance completed state at the time of obtaining the measured data are within the area 1102. The area 1102 is an area adjacent to the side where the temperature difference Y is larger than the area 1101. More specifically, the diagnosis unit 1406 can determine that there is an abnormal cooling accompanied by an abnormality in the cooling fan 180 when the value obtained by subtracting the reference value Ycr at the same timing starting from the state where maintenance related to the cooling structure unit 190 is completed from the measured data of the temperature difference Y is equal to or greater than the threshold value ΔYth.

[0223] It should be noted that in the case of an abnormal cooling accompanied by an abnormality in the cooling fan 180, in addition to the abnormality of the cooling fan 180, there may also be a case of an abnormal cooling including the presence of foreign matter.

[0224] In addition, when the deviation of the measured data of the temperature difference Y from the reference data 1100 is relatively large in the direction of decreasing the temperature difference Y, the diagnosis unit 1406 determines that there is no cooling abnormality. Specifically, the diagnosis unit 1406 may determine that there is no cooling abnormality when the coordinates defined by the measured data of the temperature difference Y and the cumulative operation time OTa in the self-maintenance completed state at the time of obtaining the measured data are within the region 1103. The region 1103 is a region adjacent to the side where the temperature difference Y is smaller than the region 1101. More specifically, the diagnosis unit 1406 may determine that there is no cooling abnormality when the value obtained by subtracting the measured data of the temperature difference Y from the reference value Ycr at the same timing starting from the state where the maintenance related to the cooling structure unit 190 is completed is equal to or greater than the threshold value ΔYth.

[0225] In this way, in this example, the control device 140 uses the reference data 1100 of the temperature difference Y representing the time change of the temperature difference Y when a cooling abnormality accompanied by the presence of a foreign object occurs, and determines the presence or absence of an abnormality in the power conversion device 100.

[0226] Thereby, the control device 140 can distinguish between a cooling abnormality accompanied by the presence of a foreign object and a cooling abnormality accompanied by an abnormality of the cooling fan 180, and determine the presence or absence of a cooling abnormality according to the magnitude of the deviation of the measured data of the temperature difference Y from the reference data 1100.

[0227] [Processing for obtaining reference data of temperature difference between heat sink temperature and internal gas temperature]

[0228] Next, with reference to Figure 12 , the processing for obtaining the reference data based on the control device 140 will be described.

[0229] Figure 12 is a flowchart schematically showing an example of the processing for obtaining the reference data of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta based on the control device 140. This flowchart is repeatedly executed for each specified period, for example, during the operation from when the power of the power conversion device 100 is turned on until it is turned off.

[0230] In this example, a flag F3 indicating whether the acquisition of the reference data of the temperature difference Y is completed is used. The flag F3 is stored in the auxiliary storage device 143, for example, and is set to "0" indicating that the reference data has not been acquired as an initial value when the power conversion device 100 is shipped from the factory. And the flag F3 can be read from the auxiliary storage device 143 into the memory device 142 for use or update when the power of the power conversion device 100 is turned on, and the latest state is stored in the auxiliary storage device 143 when the power of the power conversion device 100 is turned off.

[0231] AsFigure 12 As shown, through step S302, the recording unit 1402 determines whether the flag F3 is "0", that is, determines whether it represents a state where reference data has not been obtained. When the flag F3 is "0", the recording unit 1402 proceeds to step S304. When the flag F3 is not "0", that is, in the case of "1" indicating that reference data has already been obtained, this flowchart of the process ends.

[0232] Through step S304, the recording unit 1402 determines whether the measured data of the temperature difference Y between the latest heat sink temperature Tf and the internal gas temperature Ta is greater than the maximum temperature difference Ymax.

[0233] The maximum temperature difference Ymax represents the maximum value among the measured data of the temperature difference Y recorded in the storage unit 1403. The maximum temperature difference Ymax is set to a specified initial value at the time of factory shipment. The initial value of the maximum temperature difference Ymax serves as the lower limit value of the temperature difference Y when recording the temperature difference Y as reference data.

[0234] When the measured data of the latest temperature difference Y is greater than the maximum temperature difference Ymax, the recording unit 1402 proceeds to step S306. Otherwise, the processing of this flowchart ends.

[0235] Through step S306, the recording unit 1402 records the measured data of the latest temperature difference Y and the cumulative operation time OT of the power conversion device 100 since the start of use after factory shipment when this measured data was obtained, in association with each other, in the storage unit 1403. Specifically, the recording unit 1402 creates recording data including the measured data of the latest temperature difference Y and the cumulative operation time OT when this measured data was obtained, and saves it in the storage unit 1403.

[0236] After the processing of step S306 ends, the control device 140 proceeds to step S308.

[0237] Through step S308, the recording unit 1402 determines whether the end condition for recording the measured data in the time series of the temperature difference Y, which is equivalent to the reference data of the temperature difference Y, is satisfied.

[0238] The end condition can be, for example, that the heat sink temperature Tf reaches a temperature (hereinafter referred to as the "recording end temperature") Tfover equivalent to the end condition. The recording end temperature Tfover is set to a temperature that is somewhat lower than the overheat temperature Tferr. Additionally, the end condition can be, for example, that the number of times of recording the measured data reaches a specified number.

[0239] When the end condition for recording the reference data of the temperature difference Y is satisfied, the recording unit 1402 proceeds to step S310. When the end condition is not satisfied, this flowchart of the process ends.

[0240] Through step S310, the recording unit 1402 sets the flag F3 to "1".

[0241] After the processing in step S310 is completed, the control device 140 ends the processing of this flowchart.

[0242] Thus, in this example, the control device 140 uses, as a starting point, the state at the start of use of the power conversion device 100 after factory shipment, which is equivalent to the state where maintenance related to the power conversion device 100 is completed, and obtains time-series measurement data indicating an upward trend in the temporal change of the temperature difference Y with the passage of the cumulative operation time OT. Thereby, the control device 140 can obtain reference data for the temperature difference Y based on the obtained time-series measurement data. This is because at the initial time point after the start of use of the power conversion device 100 since factory shipment, the possibility of an abnormality occurring in the cooling fan 180 is extremely low, and the increase in the temperature difference Y at this time point can be considered to be due to the presence of foreign matter.

[0243] At this time, the control device 140 (diagnosis unit 1406) can use the record group of the measurement data stored in the storage unit 1403 as it is as reference data, or can generate an approximate formula or tabular data equivalent to the reference data based on the record group of the measurement data.

[0244] It should be noted that instead of obtaining reference data for the heat sink temperature Tf and the reference data for the temperature difference Y individually, reference data after combining the heat sink temperature Tf and the temperature difference Y can be obtained. In this case, as a record data group including the measurement data of the heat sink temperature Tf and the temperature difference Y and the cumulative operation time OT when this measurement data is obtained, reference data after combining the heat sink temperature Tf and the temperature difference Y can be obtained.

[0245] [Example of cooling abnormality diagnosis processing]

[0246] Next, with reference to Figure 13 , the cooling abnormality diagnosis processing of the power conversion device 100 performed by the control device 140 will be described.

[0247] Figure 13 is a flowchart schematically showing an example of the cooling abnormality diagnosis processing of the power conversion device 100 performed by the control device 140. This flowchart is repeatedly executed for each specified cycle, for example, during the operation of the power conversion device 100 from power-on to power-off.

[0248] In this example, a flag F2 is used to indicate whether maintenance related to the cooling structure unit 190 has been performed before the start of the current operation (power-on) of the power conversion device 100. The flag F2 is set to "1", which indicates that maintenance related to the cooling structure unit 190 has been performed, as an initial value, for example, at the first start of use (power-on) after factory shipment, and is stored in the memory device 142 between the power-on and power-off of the power conversion device 100. Also, the flag F2 can be set according to the determination result of the maintenance determination unit 1404 when the power of the power conversion device 100 is turned on after the second time after factory shipment, and maintains its state until the power is turned off. Specifically, if it is determined by the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has been performed, the flag F2 is set to "1", and this state can be maintained until the power of the power conversion device 100 is turned off. On the other hand, if it is determined by the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has not been performed, the flag F2 is set to "0", which indicates that maintenance related to the cooling structure unit 190 has not been performed, and this state can be maintained until the power of the power conversion device 100 is turned off.

[0249] As Figure 13 shown, through step S402, the diagnosis unit 1406 determines whether the flag F1 is "1", that is, determines whether the reference data has been acquired. When the flag F1 is not "1", that is, when it is "0" indicating that the reference data has not been acquired, the diagnosis unit 1406 proceeds to step S404. When the flag F1 is "1" indicating that the reference data has been acquired, the diagnosis unit 1406 proceeds to step S408.

[0250] Through step S404, the diagnosis unit 1406 determines whether the measured data of the temperature difference Y (= Tf - Ta) between the latest heat sink temperature Tf and the internal gas temperature Ta exceeds a specified threshold value Yth.

[0251] The threshold value Yth is specified in advance as the lower limit value of the temperature difference Y for determining that the power conversion device 100 has a cooling abnormality. In addition, the threshold value Yth is set to a value slightly smaller than the value of the temperature difference Y corresponding to the timing when the heat sink temperature Tf reaches the overheat temperature Tferr. Thus, the diagnosis unit 1406 can determine the occurrence of a cooling abnormality in the power conversion device 100 at a timing earlier than when the power conversion device 100 is forced to stop.

[0252] When the measured data of the latest temperature difference Y exceeds the threshold value Yth, the diagnosis unit 1406 proceeds to step S406. When it does not exceed the threshold value Yth, the current flowchart ends.

[0253] In step S406, an alarm indicating the occurrence of a cooling abnormality in the power conversion device 100 is output to the user.

[0254] The alarm can be output to the user visually by the display device 160, for example. Additionally, the alarm can be output to the user visually by the display unit 310 of the terminal device 300 by sending a signal equivalent to the alarm from the communication device 170 to the terminal device 300. Further, only the fact of the occurrence of the cooling abnormality can be displayed on the display device 160 or the display unit 310, or in addition to this fact, data indicating the operating state (operating condition) of the power conversion device 100, including the heat sink temperature Tf, the internal gas temperature Ta, and the temperature difference Y, etc., and data indicating the history of these data can be displayed as numerical values. The data indicating the history can be, for example, data indicating the change in the temperature difference Y. Additionally, the alarm can be output to the user through a sound output device such as a speaker provided in the power conversion device 100, a specified machine on which the power conversion device 100 is mounted, or the terminal device 300, etc. Hereinafter, the same applies to the alarms in steps S412, S416, and S420 described later.

[0255] After the processing in step S406 is completed, the control device 140 ends the processing of this flowchart.

[0256] On the other hand, in step S408, the diagnosis unit 1406 determines whether the flag F2 is "1", that is, determines whether maintenance related to the cooling structure unit 190 has been performed before the start of the operation (power-on) of the power conversion device 100 in this instance. When the flag F2 is not "1", that is, when it is "0" indicating that maintenance related to the cooling structure unit 190 has not been performed, the diagnosis unit 1406 proceeds to step S410, and when the flag F2 is "1" indicating maintenance related to the cooling structure unit 190, it proceeds to step S418.

[0257] It should be noted that in step S408, it can be determined whether the cumulative operation time OTa of the power conversion device 100 since the most recent maintenance related to the cooling structure unit 190 is below a specified time. The specified time is set to a value slightly smaller than the lower limit value of the time required from the state where the maintenance related to the cooling structure unit 190 is completed until a cooling abnormality due to a foreign object occurs in the power conversion device 100. In this case, when the cumulative operation time OTa is not below the specified time, the diagnosis unit 1406 proceeds to step S410, and when the cumulative operation time OTa is below the specified time, it proceeds to step S418.

[0258] Through step S410, the diagnosis unit 1406 determines whether the absolute value of the subtraction operation value ΔY (= Y - Ycr), which is obtained by subtracting the reference data (reference value Ycr) of the same cumulative operation time OTa as when the measurement data of the latest temperature difference Y is obtained from the measurement data of the latest temperature difference Y, is smaller than the threshold value ΔYth.

[0259] For example, when the reference data is represented by an approximate formula, the diagnosis unit 1406 can calculate the reference value Ycr corresponding to the cumulative operation time OTa when the measurement data of the temperature difference Y is obtained through the approximate formula. Additionally, for example, when the reference data is represented by a discretized data group such as a recorded group of measurement data or list data, there are cases where the reference value Ycr of the same cumulative operation time OTa as when the measurement data of the latest temperature difference Y is obtained exists in the storage unit 1403 and cases where it does not exist. When the reference value Ycr of the same cumulative operation time OTa as when the latest temperature difference Y is obtained exists in the storage unit 1403, the diagnosis unit 1406 can use this reference value Ycr without change. On the other hand, when the reference value Ycr of the same cumulative operation time OTa as when the latest temperature difference Y is obtained does not exist in the storage unit 1403, the reference value Ycr of the cumulative operation time OTa adjacent to the front and back of the target cumulative operation time OTa can be used to interpolate the reference value Ycr of the target cumulative operation time OTa.

[0260] When the absolute value of the subtraction operation value ΔY is smaller than the threshold value ΔYth, the diagnosis unit 1406 proceeds to step S412. In other cases, it proceeds to step S414.

[0261] Through step S412, the diagnosis unit 1406 outputs an alarm to the user indicating the occurrence of a cooling abnormality of the power conversion device 100 accompanied by the presence of a foreign object (blockage of the cooling fin portion 194 or the air intake).

[0262] After the processing of step S412 is completed, the control device 140 ends the processing of this flowchart.

[0263] On the other hand, through step S414, the diagnosis unit 1406 determines whether the subtraction operation value ΔY (= Y - Ycr) is equal to or greater than the threshold value ΔYth. When the subtraction operation value ΔY is equal to or greater than the threshold value ΔYth, the diagnosis unit 1406 proceeds to step S416. In other cases, it determines that there is no cooling abnormality of the power conversion device 100 and ends the processing of this flowchart.

[0264] Through step S416, the diagnosis unit 1406 outputs an alarm to the user indicating the occurrence of a cooling abnormality of the power conversion device 100 accompanied by an abnormality of the cooling fan 180.

[0265] After the processing in step S416 is completed, the diagnostic unit 1406 ends the processing of this flowchart.

[0266] On the other hand, through step S418, the diagnostic unit 1406 determines whether the subtraction value ΔY (= Y - Ycr) obtained by subtracting the reference data (reference value Ycr) of the same cumulative operating time OTa as when the measurement data of the latest temperature difference Y is obtained from the measurement data of the latest temperature difference Y is equal to or greater than the threshold value ΔYth. When the subtraction value ΔY is equal to or greater than the threshold value ΔYth, the diagnostic unit 1406 proceeds to step S420; otherwise, it ends the processing of this flowchart. Thus, when the power conversion device 100 is operating after maintenance related to the cooling structure unit 190, the control device 140 can determine the presence or absence of the latter cooling abnormality among the cooling abnormalities accompanied by the presence of foreign matter and the cooling abnormalities accompanied by the abnormality of the cooling fan 180.

[0267] Through step S420, the diagnostic unit 1406 outputs an alarm to the user indicating the occurrence of a cooling abnormality of the power conversion device 100 accompanied by an abnormality of the cooling fan 180.

[0268] After the processing in step S420 is completed, the diagnostic unit 1406 ends the processing of this flowchart.

[0269] Thus, in this example, the control device 140 uses the reference data of the time change of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta when a cooling abnormality accompanied by the presence of foreign matter occurs.

[0270] Thereby, the control device 140 can distinguish between the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality accompanied by the abnormality of the cooling fan 180.

[0271] In addition, in this example, when the cumulative operating time of the power conversion device 100 after maintenance related to the cooling structure unit 190 is relatively short or shorter than a specified time length, the control device 140 determines only the presence or absence of the latter among the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality accompanied by the abnormality of the cooling fan 180.

[0272] Thereby, the control device 140 can suppress the misjudgment of the cooling abnormality accompanied by the presence of foreign matter. This is because the possibility of the occurrence of the cooling abnormality accompanied by the presence of foreign matter is very low within a certain period or a period shorter than a specified time length after maintenance related to the cooling structure unit 190.

[0273] In addition, in this example, when the reference data is not obtained, the control device 140 determines the cooling abnormality of the power conversion device 100 based on the magnitude of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta.

[0274] Accordingly, although the control device 140 cannot distinguish between a cooling abnormality accompanied by the presence of a foreign object and an abnormality of the cooling fan 180, it can determine the presence or absence of a cooling abnormality of the power conversion device 100 even without obtaining reference data.

[0275] It should be noted that, in addition to the reference data obtained in a manner based on the usage environment of the actual power conversion device 100, the control device 140 can also use reference data prepared in advance. The data prepared in advance can be registered (stored) in the auxiliary storage device 143 in advance during the inspection before factory shipment, for example, or can be downloaded from the outside (for example, the arithmetic device 200) after factory shipment and stored in the auxiliary storage device 143. In this case, in the case where reference data is not obtained (the NO case in step S402), instead of the processes of steps S404 and S406, the reference data prepared in advance can be used to perform the same processes as steps S408 to S420. In addition, the control device 140 can use the reference data prepared in advance instead of the reference data obtained in a manner based on the usage environment of the actual power conversion device 100. In this case, the Figure 13 process is not performed, and the processes of steps S402 to S406 can be omitted. In addition, there can be multiple types of reference data prepared in advance. For example, multiple types of reference data can be prepared in advance according to the usage environment, and can be selected according to a specified input received from the user.

[0276] [Another Example of Cooling Abnormality Diagnosis Processing]

[0277] Next, with reference to Figure 14 , another example of the cooling abnormality diagnosis processing of the power conversion device 100 by the control device 140 will be described.

[0278] Figure 14 is a flowchart schematically showing another example of the cooling abnormality diagnosis processing of the power conversion device 100 by the control device 140. This flowchart is repeatedly executed for each specified cycle, for example, during the operation from the power-on to the power-off of the power conversion device 100.

[0279] In this example, a flag F4 indicating whether maintenance related to the cooling structure unit 190 has been performed before the start (power-on) of the current operation of the power conversion device 100 is used. Since the flag F4 is the same as the flag F2 described with reference to Figure 13 above, the description thereof is omitted here.

[0280] In addition, in this example, a flag F5 indicating the presence or absence of cooling anomalies associated with the presence of foreign objects is used. The flag F5 is stored in the memory device 142, for example, from when the power of the power conversion device 100 is turned on until it is turned off. When it is first used (power on) after being shipped from the factory, its initial value is set to "0", indicating the absence of cooling anomalies associated with the presence of foreign objects. Also, the flag F5 can be read from the auxiliary storage device 143 into the memory device 142 and utilized or updated when the power of the power conversion device 100 is turned on, and the latest state is stored in the auxiliary storage device 143 when the power of the power conversion device 100 is turned off.

[0281] As Figure 14 shown, through step S502, the diagnostic unit 1406 determines whether the flag F3 is "1", that is, determines whether the reference data acquisition is completed. When the flag F3 is not "1", that is, when it is "0" indicating that the reference data has not been acquired, the diagnostic unit 1406 proceeds to step S504. When the flag F3 is "1" indicating that the reference data acquisition is completed, the diagnostic unit 1406 proceeds to step S508.

[0282] Through step S504, since it is the same as the processing of step S404 in Figure 13 , the detailed description is omitted.

[0283] When the measured data of the latest temperature difference Y exceeds the threshold value Yth, the diagnostic unit 1406 proceeds to step S506. When it does not exceed the threshold value Yth, the diagnostic unit 1406 proceeds to step S524.

[0284] Since step S506 is the same as the processing of step S406 in Figure 13 , the detailed description is omitted. Also, the alarm in this step S506, and the alarms in the subsequent steps S512, S518, and S522 can be the same as the alarm in Figure 13 step S406.

[0285] After the processing of step S506 is completed, the control device 140 proceeds to step S514.

[0286] It should be noted that the control device 140 can omit the processing of step S514 after the processing of step S506 is completed and directly end the processing of this flowchart.

[0287] On the other hand, through step S508, the diagnosis unit 1406 determines whether the flag F4 is "1", that is, determines whether maintenance related to the cooling structure unit 190 has been performed before the start (power-on) of the operation of the power conversion device 100 this time. When the flag F4 is not "1", that is, in the case of "0" indicating that maintenance related to the cooling structure unit 190 has not been performed, the diagnosis unit 1406 proceeds to step S510. When the flag F4 is "1" indicating that maintenance related to the cooling structure unit 190 has been performed, it proceeds to step S520.

[0288] It should be noted that in step S508, it is possible to determine whether the cumulative operation time OTa of the power conversion device 100 since the most recent maintenance related to the cooling structure unit 190 is below a specified time. The specified time is set to a value slightly smaller than the lower limit value of the time required from the state where the maintenance related to the cooling structure unit 190 is completed until a cooling abnormality due to foreign matter occurs in the power conversion device 100. In this case, when the cumulative operation time OTa is not below the specified time, the diagnosis unit 1406 proceeds to step S510. When the cumulative operation time OTa is below the specified time, it proceeds to step S520.

[0289] Since the processing of step S510 is the same as that of Figure 13 step S410, the detailed description is omitted.

[0290] When the absolute value of the subtraction operation value ΔY is smaller than the threshold value ΔYth, the diagnosis unit 1406 proceeds to step S512. Otherwise, it proceeds to step S516.

[0291] Since the processing of step S512 is the same as that of Figure 13 step S412, the detailed description is omitted.

[0292] After the processing of step S512 is completed, the control device 140 proceeds to step S514.

[0293] Through step S514, the diagnosis unit 1406 sets the flag F5 to "1" indicating the presence of a cooling abnormality accompanied by the presence of foreign matter.

[0294] It should be noted that the situation where the acquisition of the reference operation possible time OTcr is not completed is equivalent to the situation where the cumulative operation time OT since the start of use of the power conversion device 100 is relatively short, and the possibility of an abnormality in the cooling fan 180 occurring is extremely low. Therefore, for the case where the condition of step S504 is satisfied and the alarm of the cooling abnormality in step S506 is output, the flag F5 is also set to "1".

[0295] After the processing of step S514 is completed, the control device 140 ends the processing of this flowchart.

[0296] On the other hand, through step S516, the diagnosis unit 1406 determines whether the subtraction operation value ΔY (= Y - Ycr) is equal to or greater than the threshold value ΔYth. When the subtraction operation value ΔY is equal to or greater than the threshold value ΔYth, the diagnosis unit 1406 proceeds to step S518. Otherwise, it determines that there is no cooling abnormality in the power conversion device 100 and proceeds to step S524.

[0297] Since the processing of step S518 is the same as that of Figure 13 step S416, a detailed description thereof is omitted.

[0298] After the processing of step S518 is completed, the diagnosis unit 1406 proceeds to step S524.

[0299] On the other hand, through step S520, the diagnosis unit 1406 determines whether the subtraction operation value ΔY (= Y - Ycr) obtained by subtracting the reference data (reference value Ycr) corresponding to the same cumulative operation time OTa as when the measurement data of the latest temperature difference Y was obtained from the measurement data of the latest temperature difference Y is equal to or greater than the threshold value ΔYth. When the subtraction operation value ΔY is equal to or greater than the threshold value ΔYth, the diagnosis unit 1406 proceeds to step S522. Otherwise, it proceeds to step S524. Thus, when the power conversion device 100 is operating after maintenance related to the cooling structure unit 190, the control device 140 can determine only the presence or absence of the latter cooling abnormality among the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality accompanied by the abnormality of the cooling fan 180.

[0300] Since the processing of step S522 is the same as that of Figure 13 step S429, a detailed description thereof is omitted.

[0301] After the processing of step S522 is completed, the diagnosis unit 1406 proceeds to step S524.

[0302] Through step S524, the flag F5 is set to "0" indicating the absence of a cooling abnormality accompanied by the presence of foreign matter.

[0303] After the processing of step S524 is completed, the control device 140 ends the processing of this flowchart.

[0304] As described above, in this example, the control device 140 uses the reference data indicating the temporal change of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta when a cooling abnormality accompanied by the presence of foreign matter occurs.

[0305] Thereby, the control device 140 can distinguish between a cooling abnormality accompanied by the presence of foreign matter and a cooling abnormality accompanied by the abnormality of the cooling fan 180.

[0306] In addition, in this example, when the cumulative operation time of the power conversion device 100 is relatively short after maintenance related to the cooling structure unit 190, the control device 140 determines only the presence or absence of the latter of the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality accompanied by the abnormality of the cooling fan 180.

[0307] Thereby, the control device 140 can suppress the misjudgment of the cooling abnormality accompanied by the presence of foreign matter. This is because the possibility of generating a cooling abnormality accompanied by the presence of foreign matter is extremely low within a certain period after maintenance related to the cooling structure unit 190.

[0308] In addition, in this example, when the reference data is not obtained, the control device 140 determines the cooling abnormality of the power conversion device 100 based on the magnitude of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta.

[0309] Thereby, although the control device 140 cannot distinguish between the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality based on the abnormality of the cooling fan 180, it can determine the presence or absence of the cooling abnormality of the power conversion device 100 even when the reference data is not obtained.

[0310] It should be noted that, in addition to the reference data obtained in a manner according to the actual usage environment of the power conversion device 100, the control device 140 can also use the reference data prepared in advance. The data prepared in advance can be registered (stored) in the auxiliary storage device 143 in advance during the inspection before factory shipment, or can be downloaded from the outside (for example, the arithmetic device 200) after factory shipment and stored in the auxiliary storage device 143. In this case, when the reference data is not obtained (in the case of NO in step S502), the processing of steps S504 and S506 can be replaced, and the reference data prepared in advance can be used to perform the same processing as steps S510 to S524. In addition, the control device 140 can use the reference data prepared in advance instead of the reference data obtained in a manner based on the actual usage environment of the power conversion device 100. In this case, the processing of Figure 7 is not performed, and the processing of steps S502 to S506 can be omitted. In addition, there can be multiple types of reference data prepared in advance. For example, multiple types of reference data can be prepared according to the usage environment, and can be selected according to a specified input received from the user. In addition, the control device 140 can diagnose the cooling abnormality related to the power conversion device 100 without distinguishing between the cooling abnormality accompanied by the presence of foreign matter and the cooling abnormality accompanied by the abnormality of the cooling fan 180. For example, the processing of steps S502, S508 to S512, and S516 to S522 can be omitted.

[0311] [Another Example of Notification Processing for Remaining Operable Time]

[0312] Next, refer to Figure 15 、 Figure 16 , and another example of the notification processing for the remaining operable time OTrem until the forced stop of the power conversion device 100 by the control device 140 will be described.

[0313] Figure 15 is a flowchart schematically showing another example of the notification processing for the remaining operable time OTrem until the forced stop of the power conversion device 100 by the control device 140. Figure 16 is a diagram showing another example of the relationship between the cumulative operation time OTa from the state where maintenance related to the cooling structure unit 190 is completed and the notification content of the remaining operable time OTrem.

[0314] As Figure 15 shown, since the processing of step S602 is the same as that of Figure 7 step S202, detailed description thereof will be omitted.

[0315] When the operable time estimation unit 1406 determines that the flag F1 is "1", it proceeds to step S604. When the flag F1 is not "1", that is, when it is "0", the processing of this flowchart is ended.

[0316] Through step S604, the operable time estimation unit 1406 determines whether the flag F5 is "1", that is, determines whether a cooling abnormality accompanied by the presence of a foreign object has occurred. When the flag F5 is "1", the operable time estimation unit 1406 proceeds to step S606. When the flag F5 is "0" indicating that no cooling abnormality accompanied by the presence of a foreign object has occurred, it proceeds to step S608.

[0317] Since step S606 is the same as the processing of Figure 7 step S204, detailed description thereof will be omitted.

[0318] After the processing of step S606 is completed, the control device 140 proceeds to step S610.

[0319] On the other hand, through step S608, the operable time estimation unit 1406 estimates (calculates) the reference operable time OTcr as the remaining operable time OTrem (OTrem = OTcr).

[0320] After the processing of step S608 is completed, the control device 140 proceeds to step S610.

[0321] Through step S610, the remaining operable time estimating unit 1406 notifies the user of the remaining operable time OTrem estimated in step S606 or step S608. Thus, the control device 140 takes the state where the maintenance of the power conversion device 100 related to the cooling structure unit 190 is completed as a starting point, and can maintain the remaining operable time OTrem as the reference operable time OTcr within the period until a cooling abnormality related to the presence of a foreign object occurs. Further, when a cooling abnormality related to the presence of a foreign object occurs, the control device 140 can notify the user of the remaining operable time OTrem in a manner of successively subtracting from the reference operable time OTcr according to the elapsed cumulative operation time OTa (see Figure 16 ).

[0322] After the process of step S610 is completed, the control device 140 ends the process of this flowchart.

[0323] As described above, in this example, when a cooling abnormality of the power conversion device 100 occurs, the control device 140 notifies the remaining operable time OTrem to the user through the display device 160 and the communication device 170 in a manner of performing subtraction operations over time.

[0324] Thus, the control device 140 can, when limited to the occurrence of a cooling abnormality of the power conversion device 100, use the remaining operable time OTrem that performs successive subtraction operations over time.

[0325] [Function]

[0326] Next, the function of the power conversion device 100 (control device 140) of the above-described embodiment will be described.

[0327] In this embodiment, the power conversion device 100 includes power devices (for example, semiconductor diode SD, semiconductor switch SW), a cooling structure unit 190, a cooling fan 180, and a diagnosis unit 1405. Specifically, the cooling structure unit 190 is used for heat dissipation of the power devices. In addition, the cooling fan 180 is used for blowing air to the cooling structure unit 190. Further, the diagnosis unit 1405 diagnoses an abnormality (cooling abnormality) related to the cooling performance of the cooling structure unit 190 and the cooling fan 180 based on the tendency of the time change of the temperature difference Y between the heat sink temperature Tf and the internal gas temperature Ta.

[0328] Accordingly, the control device 140 can utilize the difference in the tendency of the time change of the temperature difference Y between the cooling abnormality accompanied by the abnormality of the cooling fan 180 and the cooling abnormality accompanied by the presence of a foreign object. Therefore, the control device 140 can distinguish the cooling abnormality accompanied by the abnormality of the cooling fan 180 from the cooling abnormality accompanied by the presence of a foreign object.

[0329] In addition, in the present embodiment, the diagnosis unit 1405 can distinguish the abnormality of the cooling performance accompanied by the presence of a foreign object from the abnormality of the cooling performance accompanied by the abnormality of the cooling fan 180 based on the rising speed of the temperature difference Y.

[0330] Accordingly, the control device 140 can utilize the difference in the rising speed of the temperature difference Y to specifically distinguish the cooling abnormality accompanied by the abnormality of the cooling fan 180 from the cooling abnormality accompanied by the presence of a foreign object.

[0331] In addition, in the present embodiment, the power conversion device 100 includes a storage unit 1403. Specifically, the storage unit 1403 can store reference data indicating the tendency of the time change of the temperature difference Y in the case of an abnormality of the cooling performance accompanied by the presence of a foreign object. And the diagnosis unit 1405 can determine that there is an abnormality of the cooling performance accompanied by the presence of a foreign object when the deviation between the measured data of the temperature difference Y and the reference data corresponding to the same timing as the measured data is relatively small, and determine that there is an abnormality of the cooling performance accompanied by the abnormality of the cooling fan 180 when the deviation between the measured data of the temperature difference Y and the reference data corresponding to the same timing as the measured data is relatively large in the direction of the increase of the temperature difference Y.

[0332] Accordingly, the control device 140 can utilize the reference data indicating the tendency of the time change of the temperature difference Y in the case of an abnormality of the cooling performance accompanied by the presence of a foreign object to specifically distinguish the cooling abnormality accompanied by the abnormality of the cooling fan 180 from the cooling abnormality accompanied by the presence of a foreign object.

[0333] In addition, in the present embodiment, the power conversion device 100 may include a maintenance determination unit 1404. Specifically, the maintenance determination unit 1404 can determine that maintenance related to the cooling structure unit 190 has been performed. In addition, the reference data can use the state after the completion of the maintenance related to the cooling structure unit 190 as a starting point and represent the time change of the temperature difference Y when a cooling abnormality accompanied by the presence of a foreign object occurs. And the diagnosis unit 1405 can use the time point when the maintenance determination unit 1404 determines that maintenance related to the cooling structure unit 190 has been performed as a starting point and perform a diagnosis related to the abnormality of the cooling performance based on the deviation state between the measured data of the temperature difference Y in time series and the reference data corresponding to the same timing as the measured data.

[0334] Accordingly, the control device 140 can perform diagnosis related to cooling anomalies while differentiating between cooling anomalies associated with an abnormality of the cooling fan 180 and cooling anomalies associated with the presence of foreign matter, based on the passage of time starting from the state where maintenance related to the cooling structure unit 190 is completed.

[0335] In addition, in the present embodiment, the diagnosis unit 1405 can calculate the difference (subtraction operation value ΔY) between the measurement data of the temperature difference Y and the reference data (reference value Ycr) corresponding to the same timing as the measurement data, and perform diagnosis related to an abnormality of the cooling performance by comparing this difference with a threshold value ΔYth.

[0336] Accordingly, the control device 140 can specifically perform diagnosis related to cooling anomalies while differentiating between cooling anomalies associated with an abnormality of the cooling fan 180 and cooling anomalies associated with the presence of foreign matter.

[0337] In addition, in the present embodiment, the power conversion device 100 can include a maintenance determination unit. And when the cumulative operation time of the power conversion device 100 after it is determined by the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has been performed is relatively short, the diagnosis unit 1405 can determine only the presence or absence of a cooling anomaly associated with an abnormality of the cooling fan 180 among the cooling anomalies associated with the presence of foreign matter and the cooling anomalies associated with an abnormality of the cooling fan 180.

[0338] Accordingly, as a first object, as described above, the control device 140 of the present embodiment can suppress incorrect diagnosis, specifically, can suppress misjudgment of a cooling anomaly associated with the presence of foreign matter.

[0339] In addition, in the present embodiment, the storage unit 1403 can store reference data obtained based on the measurement data of the temperature difference Y in time series from the start of the first use of the power conversion device 100 after factory shipment to a specified timing. And after reaching the specified timing (specifically, the timing when the above-mentioned end condition is satisfied), the diagnosis unit 1405 can perform diagnosis related to an abnormality of the cooling performance based on the magnitude of the deviation between the measurement data of the temperature difference Y and the reference data corresponding to the same timing as the measurement data.

[0340] Accordingly, the control device 140 can use reference data according to the usage environment of the power conversion device 100 and the like. Therefore, the control device 140 can improve the diagnosis accuracy of cooling anomalies, such as the determination accuracy of the presence or absence of cooling anomalies and the differentiation accuracy between cooling anomalies associated with the presence of foreign matter and cooling anomalies associated with an abnormality of the cooling fan 180.

[0341] In addition, in the present embodiment, the storage unit 1403 may store reference data obtained based on the measurement data of the temperature difference Y in time series during the period from the time point when the temperature difference Y exceeds a specified value after the initial start of use after the power conversion device 100 is shipped from the factory to a specified timing.

[0342] Thereby, the control device 140 can obtain reference data based on the measurement data in a state where the influence of the presence of foreign matters such as blockage of the cooling fin portion 194 and the suction port becomes relatively large. Therefore, in a situation where the influence of the presence of foreign matters such as blockage of the cooling fin portion 194 and the suction port is relatively small, the control device 140 does not need to record the measurement data, and can reduce the processing load for obtaining the reference data.

[0343] In addition, in the present embodiment, the storage unit 1403 may store the measurement data of the temperature difference Y in association with the cumulative operation time since the start of use of the power conversion device 100 when the measurement data is obtained.

[0344] Thereby, the control device 140 can directly use the recorded data of the combination of, for example, the measurement data of the temperature difference Y and the cumulative operation time since the start of use of the power conversion device 100 when the measurement data is obtained as the reference data.

[0345] In addition, in the present embodiment, the diagnosis unit 1405 may perform diagnosis related to cooling abnormality of the power conversion device 100 based on the magnitude of the temperature difference Y before reaching the specified timing.

[0346] Thereby, the control device 140 can also perform diagnosis related to cooling abnormality of the power conversion device 100 before obtaining the reference data according to the use environment of the power conversion device 100 and the like.

[0347] In addition, in the present embodiment, the power conversion device 100 includes, for example, power devices such as a semiconductor diode SD and / or a semiconductor switch SW, a cooling structure portion 190, a cooling fan 180, a drive control portion 1401, and an operable time estimation portion 1405. Specifically, the cooling structure portion 190 is for dissipating heat of the power device. In addition, the cooling fan 180 is for blowing air to the cooling structure portion 190. In addition, the drive control portion 1401 forcibly stops the operation of the power conversion device 100 after the temperature of the cooling structure portion 190 reaches the overheat temperature Tferr. And the operable time estimation portion 1405 estimates the operable time of the power conversion device 100 until the heat sink temperature Tf reaches the overheat temperature Tferr based on the tendency of the time change of the temperature (heat sink temperature Tf) of the cooling structure portion 190.

[0348] Thus, as a second object, as described above, the control device 140 of the present embodiment uses the estimated operating possible time of the power conversion device 100 until the heat sink temperature Tf reaches the overheat temperature Tferr, and notifies the user of the period when the power conversion device 100 is forced to stop.

[0349] In addition, in the present embodiment, the operating possible time estimation unit 1405 can estimate the operating possible time (reference operating possible time OTcr) of the power conversion device 100 for the entire period from the initial use start after the factory shipment of the power conversion device 100 to a specified timing based on the measurement data of the time-series heat sink temperature Tf.

[0350] Thus, the control device 140 can estimate the period when the power conversion device 100 is forced to stop, taking the operating possible time of the power conversion device 100 for the entire period from the state where maintenance related to the cooling structure unit 190 is completed to the time when the temperature of the cooling structure unit 190 reaches the overheat temperature Tferr as a reference.

[0351] In addition, in the present embodiment, the power conversion device 100 may include a maintenance determination unit 1404. Specifically, the maintenance determination unit 1404 can determine that maintenance related to the cooling structure unit 190 has been performed. And the operating possible time estimation unit 1405 can subtract the accumulated operating time OTa of the power conversion device 100 when it is determined by the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has been performed from the estimated operating possible time (reference operating possible time OTcr) of the power conversion device 100 for the entire period, thereby estimating the remaining operating possible time OTrem of the power conversion device 100 until the heat sink temperature Tf reaches the overheat temperature Tferr.

[0352] Thus, the control device 140 can specifically estimate the remaining operating possible time OTrem.

[0353] In addition, in the present embodiment, the power conversion device 100 may include a notification unit such as a display device 160 and a communication device 170, for example. Specifically, the notification unit can notify the user of the remaining operating possible time OTrem of the power conversion device 100 until the temperature of the cooling structure unit 190 reaches the overheat temperature Tferr, estimated by the operating possible time estimation unit 1405.

[0354] Thus, the power conversion device 100 can specifically notify the user of the period when the power conversion device 100 is forced to stop based on the estimated remaining operating possible time OTrem of the power conversion device 100.

[0355] In addition, in the present embodiment, the power conversion device 100 may include a diagnosis unit 1406. Specifically, the diagnosis unit 1406 may perform a diagnosis related to an abnormality based on the cooling performance of the cooling structure unit 190. Further, the notification unit may, when it is determined by the diagnosis unit 1406 that there is an abnormality in the cooling performance based on the cooling structure unit 190, notify the user of the remaining possible operation time OTrem of the power conversion device 100 in a manner of performing subtraction as the cumulative operation time of the power conversion device 100 elapses.

[0356] Thus, the power conversion device 100 can notify the remaining possible operation time OTrem that is successively subtracted as the cumulative operation time of the power conversion device 100 elapses, in a case where an abnormality in the cooling performance based on the cooling structure unit 190 has occurred.

[0357] In addition, in the present embodiment, the power conversion device 100 may include a maintenance determination unit 1404. Further, the notification unit may notify the user of the remaining possible operation time OTrem of the power conversion device 100 in a manner of performing subtraction as the cumulative operation time of the power conversion device 100 elapses, starting from when it is determined by the maintenance determination unit 1404 that maintenance related to the cooling structure unit 190 has been performed.

[0358] Thus, the power conversion device 100 can notify the user of the remaining possible operation time OTrem that is successively subtracted as the cumulative operation time of the power conversion device 100 elapses from the state where the maintenance related to the cooling structure unit 190 has been completed.

[0359] As described above, although the embodiments have been described in detail, the present invention is not limited to specific embodiments, and various modifications / changes can be made within the scope of the gist described in the claims.

Claims

1. A power conversion device, comprising: A power device; A cooling structure unit for dissipating heat of the above-mentioned power device; A blower unit for blowing air to the above-mentioned cooling structure unit; A diagnosis unit for diagnosing an abnormality related to the cooling performance based on the tendency of the time change of the temperature difference between the temperature of the above-mentioned cooling structure unit and the temperature of the air inside the power conversion device; and A storage unit for storing reference data representing the tendency of the time change of the above-mentioned temperature difference when an abnormality of the above-mentioned cooling performance accompanied by the presence of a foreign object occurs, When the deviation ratio of the measured data of the above-mentioned temperature difference from the reference data corresponding to the same timing as the measured data is smaller than a first threshold, the above-mentioned diagnosis unit determines that there is an abnormality of the above-mentioned cooling performance accompanied by the presence of a foreign object. When the deviation of the measured data of the above-mentioned temperature difference from the reference data corresponding to the same timing as the measured data is larger than a second threshold in the direction of increasing the above-mentioned temperature difference, the above-mentioned diagnosis unit determines that there is an abnormality of the above-mentioned cooling performance accompanied by an abnormality of the above-mentioned blower unit.

2. The power conversion device according to claim 1, wherein It further includes a maintenance determination unit for determining that maintenance related to the above-mentioned cooling structure unit has been performed, The above-mentioned reference data takes the state after the completion of maintenance related to the above-mentioned cooling structure unit as a starting point and represents the time change of the above-mentioned temperature difference when an abnormality of the above-mentioned cooling performance accompanied by the presence of a foreign object occurs, When the above-mentioned diagnosis unit determines through the above-mentioned maintenance determination unit that maintenance related to the above-mentioned cooling structure unit has been performed, it takes this as a starting point and diagnoses an abnormality related to the above-mentioned cooling performance based on the deviation state between the measured data of the above-mentioned temperature difference in time series and the reference data corresponding to the same timing as the measured data.

3. The power conversion device according to claim 1 or 2, wherein The above-mentioned diagnosis unit calculates the difference between the measured data of the above-mentioned temperature difference and the reference data corresponding to the same timing as the measured data, and diagnoses an abnormality related to the above-mentioned cooling performance based on the comparison between the above-mentioned difference and a specified threshold.

4. The power conversion device according to claim 1 or 2, wherein It further includes a maintenance determination unit for determining that maintenance related to the above-mentioned cooling structure unit has been performed, When the cumulative operating time of the power conversion device after the above-mentioned diagnosis unit determines through the above-mentioned maintenance determination unit that maintenance related to the above-mentioned cooling structure unit has been performed is shorter than a specified time length, the above-mentioned diagnosis unit only determines the presence or absence of an abnormality of the above-mentioned cooling performance accompanied by an abnormality of the above-mentioned blower unit among the abnormality of the above-mentioned cooling performance accompanied by the presence of a foreign object and the abnormality of the above-mentioned cooling performance accompanied by an abnormality of the above-mentioned blower unit.

5. The power conversion device according to claim 1 or 2, wherein The above-mentioned storage unit stores the above-mentioned reference data obtained based on the measured data of the above-mentioned temperature difference in time series during the period from the start of the first use after the power conversion device is shipped from the factory to a specified timing, After reaching the specified timing, the above-described diagnostic unit performs a diagnosis related to an abnormality in the above-described cooling performance based on the magnitude of the deviation between the measurement data of the above-described temperature difference and the above-described reference data corresponding to the same timing as that of the measurement data.

6. The power conversion device according to claim 5, wherein the above-described storage unit stores the above-described reference data obtained based on the measurement data of the above-described temperature difference in time series during the period from the time point when the above-described temperature difference exceeds a specified value to the above-described specified timing after the start of the first use after the power conversion device is shipped from the factory.

7. The power conversion device according to claim 6, wherein the above-described storage unit stores the measurement data of the above-described temperature difference in association with the cumulative operation time of the power conversion device from the start of use when the measurement data of the above-described temperature difference is obtained.

8. The power conversion device according to claim 5, wherein before reaching the above-described specified timing, the above-described diagnostic unit performs a diagnosis related to an abnormality in the above-described cooling performance based on the magnitude of the above-described temperature difference.

9. An information processing device related to a power conversion device, the power conversion device having: a power device; a cooling structure unit for dissipating heat of the above-described power device; and a blower unit that blows air to the above-described cooling structure unit, the information processing device: performs a diagnosis related to an abnormality in the cooling performance based on the tendency of the time change of the temperature difference between the temperature of the above-described cooling structure unit and the temperature of the air inside the above-described power conversion device, when the deviation between the measurement data of the above-described temperature difference and the reference data corresponding to the same timing as that of the measurement data is smaller than a first threshold, it is determined that there is an abnormality in the above-described cooling performance accompanied by the presence of foreign matter, and when the deviation between the measurement data of the above-described temperature difference and the above-described reference data at the same timing as that of the measurement data is larger than a second threshold in the direction in which the above-described temperature difference increases, it is determined that there is an abnormality in the above-described cooling performance accompanied by an abnormality in the above-described blower unit, wherein the above-described reference data is data representing the tendency of the time change of the above-described temperature difference in the case of an abnormality in the above-described cooling performance accompanied by the presence of foreign matter.

10. An information processing method executed by an information processing device related to a power conversion device, the power conversion device having: a power device; a cooling structure unit for dissipating heat of the above-described power device; and a blower unit that blows air to the above-described cooling structure unit, in this information processing method, a diagnosis related to an abnormality in the cooling performance based on the tendency of the time change of the temperature difference between the temperature of the above-described cooling structure unit and the temperature of the air inside the above-described power conversion device is performed. When the deviation between the measured data of the temperature difference and the reference data corresponding to the same timing as the measured data is smaller than the first threshold, it is determined that there is an abnormality in the cooling performance accompanied by the presence of a foreign object. When the deviation between the measured data of the temperature difference and the reference data at the same timing as the measured data is larger than the second threshold in the direction of increasing the temperature difference, it is determined that there is an abnormality in the cooling performance accompanied by an abnormality in the air supply unit. Among them, the reference data is data indicating the tendency of the temporal change of the temperature difference in the case of an abnormality in the cooling performance accompanied by the presence of a foreign object.

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