JP5785822B2 - Injection molding machine and power semiconductor element consumption monitoring system - Google Patents

Description

  The present invention relates to an injection molding machine including a power semiconductor element consumption level monitoring system for monitoring a consumption level of a power semiconductor element in a power conversion apparatus, and to the power semiconductor element consumption level monitoring system.

  Conventionally, the life monitoring of the power switching element that monitors the degree of wear of the power switching element, notifies the time of maintenance of the power switching element before the end of its life, and executes the measures to prevent the destruction of the power switching element. An apparatus is known (for example, refer to Patent Document 1).

  This device is applied to an inverter, and each of the plurality of power switching elements is individually turned on / off to output an operation command for rotating the motor (on state), and all of the power switching elements are turned off. A switch that switches between a state in which an operation command for stopping the motor is output (off state) is provided, and the number of times the operation command is output every time the switch is turned on is counted as the number of operations. When it exceeds, the arrival of the replacement time of the power switching element is notified, or the operation of the power switching element is stopped.

  Also, it is necessary to estimate the temperature change of the power transistor constituting the switching circuit based on the operating frequency, carrier frequency, and output current of the switching circuit, and to generate the temperature change amplitude prepared in advance and the temperature change amplitude. Referring to the graph showing the relationship between the power cycle number, the power cycle number (relative to the total power cycle number which is the total life of the power transistor) corresponding to the estimated amplitude of temperature change is derived, and the life of the power transistor There is known an electric motor control device that estimates the above (for example, see Patent Document 2).

JP-A-8-51768 Japanese Patent No. 4367339

  However, since the device described in Patent Document 1 monitors the life of the power switching element based only on the number of output of the operation command regardless of the operation state of the inverter in which the operation frequency, the output current, or the like changes, it is more than necessary. There is a case where the replacement of the power switching element is promptly promoted or the destruction of the power switching element occurs before notifying the arrival of the replacement timing of the power switching element.

  Further, although the device described in Patent Document 2 considers the operating state (temperature change) of the power transistor, it continuously calculates the temperature of the power transistor and maximizes the temperature of the power transistor in a predetermined calculation cycle. After calculating the temperature change amplitude, which is the difference between the point and the minimum point, the number of power cycles corresponding to the calculation cycle is derived, so the amount of calculation for estimating the life of the power transistor is Become enormous.

  Therefore, the present invention relates to an injection molding machine including a power semiconductor element wear level monitoring system for more accurately monitoring a power semiconductor element wear level in a power conversion apparatus with a lower calculation load, and the power semiconductor element wear level. The purpose is to provide a monitoring system.

In order to achieve the above object, an injection molding machine according to an embodiment of the present invention is an injection molding machine including a power semiconductor element consumption level monitoring system for monitoring a consumption level of a power semiconductor element in a power converter. An operation state determination unit that determines which of a plurality of preset operation patterns corresponds to the operation state of the power converter, and the power semiconductor element when each of the plurality of operation patterns is executed The consumption level reference table that stores the consumption level of the power in advance and the consumption level reference table are used to determine the consumption level of the power semiconductor element when the operation pattern determined by the operation state determination unit is executed. and a consumption degree integration unit for integrating acquired in period, the operating condition determining module is the operating frequency and the carrier frequency is set to drive the semiconductor element for electric power The operation pattern is determined on the basis of the output current output from the power semiconductor element, and the wear level integration unit uses the wear level acquired in the first cycle as it is as a wear level integrated value. The newly acquired wear level is added to the wear level integrated value in the period .

A power semiconductor element consumption level monitoring system according to an embodiment of the present invention is a power semiconductor element consumption level monitoring system for monitoring a consumption level of a power semiconductor element in a power conversion device, wherein the power conversion device includes: An operation state determination unit that determines which one of the plurality of operation patterns set in advance corresponds to the operation state, and stores in advance the degree of wear of the power semiconductor element when each of the plurality of operation patterns is executed Referring to the wear level reference table to be used and the wear level reference table, the wear level of the power semiconductor element when the operation pattern determined by the operation state determination unit is executed is acquired at a predetermined cycle and integrated. comprising a consumption degree integration unit that, the, the operating condition determining module includes a driving frequency and the carrier frequency is set to drive the power semiconductor device, for the power The operation pattern is determined based on the output current output by the conductor element, and the wear level integration unit uses the wear level acquired in the first cycle as the wear level integrated value as it is. It is characterized in that the newly acquired wear degree is added to the degree integrated value .

  By the means described above, the present invention provides an injection molding machine having a power semiconductor element consumption level monitoring system that monitors the consumption level of power semiconductor elements in a power converter more accurately and with a lower calculation load, and the power semiconductor thereof. An element consumption monitoring system can be provided.

It is a figure which shows the principal part structure of the injection molding machine which concerns on the Example of this invention. It is a functional block diagram which shows the structural example of the semiconductor element consumption degree monitoring system for electric power mounted in the injection molding machine concerning the Example of this invention. It is a functional block diagram which shows the structural example of a control card. It is a figure which shows the structural example of a consumption level reference table. It is a flowchart which shows the flow of a consumption level monitoring process.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a main configuration of an example of an injection molding machine according to an embodiment of the present invention.

  In this embodiment, the injection molding machine is an electric injection molding machine and includes an injection servo motor 30A. The rotation of the injection servo motor 30 </ b> A is transmitted to the ball screw 2. A nut 3 that moves forward and backward by the rotation of the ball screw 2 is fixed to a pressure plate 4. The pressure plate 4 is movable along guide bars 5 and 6 fixed to a base frame (not shown). The forward / backward movement of the pressure plate 4 is transmitted to the screw 59 via the bearing 7, the load cell 8, and the injection shaft 9. The screw 59 is disposed in the heating cylinder 51 so as to be rotatable and movable in the axial direction. A hopper 52 for supplying resin is provided at the rear portion of the screw 59 in the heating cylinder 51. The rotation motion of a servo motor 30B for screw rotation is transmitted to the injection shaft 9 via a connecting member 53 such as a belt or a pulley. That is, the screw 59 is rotated when the injection shaft 9 is rotationally driven by the screw rotating servo motor 30B.

  In the plasticizing / metering step, the molten resin is stored in the front portion of the screw 59, that is, on the nozzle 51-1 side of the heating cylinder 51 by retreating the screw 59 in the heating cylinder 51. In the injection process, molding is performed by filling the mold with molten resin stored in front of the screw 59 and pressurizing it. At this time, the force pushing the resin is detected as a reaction force by the load cell 8. That is, the resin pressure at the front part of the screw is detected. The detected pressure is amplified by the load cell amplifier 55 and input to the controller 56 (control device) functioning as control means. In the pressure holding step, the resin filled in the mold is maintained at a predetermined pressure.

  A position detector 57 for detecting the amount of movement of the screw 59 is attached to the pressure plate 4. The detection signal of the position detector 57 is amplified by the amplifier 58 and input to the controller 56. This detection signal may be used to detect the moving speed of the screw 59.

  The servo motors 30A and 30B are provided with rotational speed detection devices (encoders) 42A and 42B for detecting the rotational speed, respectively. The rotational speeds detected by the rotational speed detection devices 42A and 42B are input to the controller 56, respectively.

  The servo motor 30C is a servo motor for opening and closing the mold, and the servo motor 30D is a servo motor for taking out a molded product (ejector). The servo motor 30C drives a toggle link (not shown), for example, and realizes mold opening and closing. Further, the servo motor 30D realizes the removal of the molded product by moving an ejector rod (not shown) via, for example, a ball screw mechanism. The servo motors 30C and 30D are provided with rotational speed detection devices (encoders) 42C and 42D for detecting the rotational speed, respectively. The rotational speeds detected by the rotational speed detection devices 42C and 42D are respectively input to the controller 56.

  The controller 56 is mainly composed of a microcomputer, and includes, for example, a CPU, a ROM for storing control programs, a readable / writable RAM for storing calculation results, a timer, a counter, an input interface, an output interface, and the like. Have.

  The controller 56 sends a current (torque) command corresponding to each process to each of the servo motors 30A to 30D. For example, the controller 56 realizes the plasticizing / metering process by controlling the rotation speed of the servo motor 30B. Further, the controller 56 controls the rotation speed of the servo motor 30A to realize the injection process and the pressure holding process. Similarly, the controller 56 controls the rotation speed of the servo motor 30C to realize the mold opening process and the mold closing process. Further, the controller 56 controls the number of rotations of the servo motor 30D to realize a molded product removal step.

  The user interface 35 includes an input setting unit that can set molding conditions for each molding process such as a mold opening / closing process and an injection process. The user interface 35 includes an input unit that receives various instructions from the user, and an output unit (for example, a display device and an audio output device) that outputs various types of information to the user.

  One cycle of injection molding in an injection molding machine typically involves pressing a nozzle 51-1 against a mold closing process for closing a mold, a mold clamping process for clamping the mold, and a sprue (not shown) of the mold. Nozzle touch process, an injection process in which the screw 59 in the heating cylinder 51 is advanced to inject the molten material accumulated in front of the screw 59 into a mold cavity (not shown), and then generation of bubbles and sink marks The screw 59 is rotated for the next cycle in the time between the pressure holding step of applying a holding pressure for a while and the molten material filled in the mold cavity is cooled and solidified, A plasticizing / weighing process for accumulating the resin in the front of the heating cylinder 51 while melting the resin, a mold opening process for removing the solidified molded product from the mold, and a molded product provided in the mold. Composed of a demold extruding out by a pin (not shown).

  The power conversion device 10 is a device that converts AC power into DC power, and further converts the DC power into AC power suitable for various loads. For example, the rectifier 11, the smoothing circuit 12, and the inverter circuits 13A and 13B. , 13C, 13D (hereinafter also collectively referred to as "inverter circuit 30". The same applies to "motor 30", "rotational speed detection device 42", and "output current detection device 41" described later). .

  The rectifier 11 converts AC power from the AC power supply 20 into DC power and outputs the DC power to the smoothing circuit 12.

  The smoothing circuit 12 is a circuit that smoothes the DC power rectified by the rectifier 11, and includes a voltage detector 12a. The voltage detector 12 a is a device that detects a smoothed DC voltage, and outputs the detected value to the controller 56.

  The inverter circuit 13 is composed of a power switching element such as an IGBT (Insulated Gate Bipolar Transistor), an IPM (Intelligent Power Module), or a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), for example. Convert to AC power. The inverter circuit 13 is a semiconductor circuit that has a life due to a power cycle (hereinafter referred to as “power cycle life”) and needs to be replaced before the power cycle life is exhausted. In this embodiment, the inverter circuit 13A is connected to the injection servo motor 30A, the inverter circuit 13B is connected to the screw rotating servo motor 30B, and the inverter circuit 13C is connected to the mold opening / closing servo motor 30C. The inverter circuit 13D is connected to the servo motor 30D for the ejector.

  The output current detection device 41 is a device that detects the current supplied to the motor 30, and outputs the detected value to the controller 56.

  The AC power supply 20 is, for example, a commercial three-phase AC power supply and supplies an AC current to the power conversion device 10.

  FIG. 2 is a functional block diagram showing a configuration example of a power semiconductor element consumption level monitoring system 100 that monitors the consumption level of power semiconductor elements in the power conversion apparatus 10 of FIG. In FIG. 2, for clarity, one inverter circuit 13, one motor 30, one output current detection device 41, and one rotational speed detection device 42 are arranged. Assume that they are arranged in parallel. However, the configuration in which the inverter circuit 13, the motor 30, the output current detection device 41, and the rotation speed detection device 42 are arranged one by one is not excluded.

  The power semiconductor element wear level monitoring system 100 mainly includes a power conversion device 10, an AC power supply 20, a motor 30, an output current detection device 41, a rotation speed detection device 42, a display device 43, an audio output device 44, and a control card 40. And a driver card 50.

  The power converter 10 is distinguished in its operation state by a plurality of operation patterns.

  The “operation pattern” is pre-registered as a typical pattern of the operation state of the power conversion device 10 over a predetermined period, which is characterized by an operation frequency, an output current, a carrier frequency used in PWM (Pulse Width Modulation) control, and the like. Is.

  For example, the operation pattern includes an injection motor, a mold clamping motor, a resin metering motor to perform each of various processes such as mold clamping, molten resin filling, pressure holding, cooling, mold opening, and molded product removal, Each of the operation states of the inverter when driving each motor such as an ejector motor is registered in advance as a typical pattern. In this case, one injection molding cycle is represented by a plurality of operation patterns. It will be.

  The operation pattern is a typical pattern of the operation state of the inverter when driving the related motor in a part of a specific process (for example, driving the mold clamping motor in the first half of the mold clamping process). In this case, various processes such as a mold clamping process are represented by a plurality of operation patterns.

  Furthermore, even if the operation pattern is a pattern having a larger group than the operation pattern corresponding to each of the various processes (for example, the operation state of the inverter across a plurality of processes is registered in advance as a typical pattern). It may be a pattern having a smaller group (for example, an operation pattern divided in units of several tens of milliseconds).

  The control card 40 is a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM, an A / D (Analog / Digital) converter, and the like. A program corresponding to each of the units 450 (see FIG. 3) is read from the ROM or RAM, and the CPU executes processing corresponding to each functional unit.

  The motor speed correction unit 400 and the wear level monitoring unit 450 are implemented by hardware using an analog circuit, a digital circuit, a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), an FPAA (Field Programmable Analog Array), or the like. It may be configured.

  In addition, the control card 40 acquires detection values from the output current detection device 41 and the rotation speed detection device 42, executes processing by the various functional units described above, and controls the display device 43 and the audio output device 44. Output a signal.

  Further, the control card 40 generates a timing control signal according to a desired motor rotation speed command value through vector control by PWM driving using a predetermined carrier frequency, and sends the generated timing control signal to the driver card 50. Output.

  The driver card 50 is a device for driving the inverter circuit 13 of the power conversion device 10. For example, the driver card 50 amplifies a timing control signal from the control card 40 and outputs the amplified signal to the inverter circuit 13.

  The inverter circuit 13 switches on / off of the power switching element according to a timing control signal from the driver card 50, and performs a conversion operation from DC power to AC power.

  In the present embodiment, the control card 40 and the driver card 50 each constitute a part of the controller 56.

  The display device 43 is a device for displaying various types of information. For example, the display device 43 is a liquid crystal display, an LED (Light Emitting Diode), or the like, and the degree of consumption of the power semiconductor element according to the control signal output from the control card 40. And information indicating the arrival of replacement time.

  The audio output device 44 is a device for outputting various kinds of information as audio, for example, a speaker or a buzzer, and information indicating the arrival of the replacement time of the power semiconductor element according to a control signal output from the control card 40 Is output as audio.

  In the present embodiment, the display device 43 and the audio output device 44 each constitute a part of the user interface 35.

  Next, components of the control card 40 will be described with reference to FIG. FIG. 3 is a functional block diagram illustrating a configuration example of the control card 40.

  The motor speed correction unit 400 is a functional unit for correcting the rotation speed of the motor 30. For example, based on the output of the rotation speed detection device 42, a motor rotation speed command value and a measured motor rotation speed value are calculated. The difference between the values is derived, and the command value of the motor rotation speed is corrected according to the derived difference so that the motor rotation speed approaches the target value.

  The consumption level monitoring unit 450 is a functional unit for monitoring the consumption level of the power semiconductor element in the power conversion device 10, and includes an operation state determination unit 451, a consumption level integration unit 452, a cumulative consumption level display unit 453, and a replacement The time notification unit 454 is configured.

  The consumption level reference table 460 is a reference table that stores the consumption level of the power semiconductor element so that it can be referred to when each of the plurality of operation patterns of the power conversion device 10 is executed. It is stored in a non-volatile storage medium such as NVRAM.

  “Degree of wear” is an index that represents the influence of a specific operation pattern on the lifetime of a specific power semiconductor element. For example, the specific power semiconductor element when the specific operation pattern is repeatedly executed It is represented by a value obtained by multiplying the reciprocal of the power cycle life (maximum power cycle number) (consumption level per power cycle) by the number of power cycles per specific operation pattern.

  Specifically, when the maximum power cycle number of a specific power semiconductor element when a specific operation pattern is repeatedly executed is 100,000, and the power cycle number per operation pattern is 10 times, The degree of wear is 1 / 100,000 times × 10 times = 0.0001 (0.01%), and a specific operation pattern is executed once, and 0% of the total life of a specific power semiconductor element is obtained. 01% is spent.

  The wear level reference table 460 is a three-dimensional table having, for example, an operating frequency, a carrier frequency, and an output current as three variables, and is specified by three values of the operating frequency, the carrier frequency, and the output current. The table value of one table cell (corresponding to one of the operation patterns) represents the degree of wear of the power semiconductor element when the corresponding operation pattern is executed.

  Further, the table value of each table cell in the consumption level reference table 460 includes a plurality of values representing the consumption levels corresponding to the plurality of power semiconductor elements in the power conversion device 10.

  FIG. 4 is a diagram illustrating a configuration example of the consumption level reference table 460. The consumption level reference table 460 includes three types of operation frequencies OF1 to OF3, five types of output currents A1 to A5, and five types of carrier frequencies. Indicates that the table is a three-dimensional table composed of CF1 to CF5.

  In FIG. 4, when the operation state of the power conversion device 10 is an operation pattern specified by the operation frequency OF1, the output current A2, and the carrier frequency CF3, the power in the power conversion device 10 is obtained by executing the operation pattern. The degree of wear of each semiconductor element (for example, four) is represented by the four table values a, b, c, and d of the table cell CL1.

  It should be noted that the wear level reference table 460 may be a two-dimensional reference table in which the output current and one of the operation frequency and the carrier frequency are two variables, or the operation frequency, the carrier frequency, and the output It may be a multi-dimensional reference table of four or more dimensions composed of four or more variables including current.

  The cumulative consumption level storage unit 470 is an area for storing the cumulative consumption level of each of the plurality of power semiconductor elements in the power conversion device 10. For example, the cumulative consumption level storage unit 470 is on a rewritable nonvolatile storage medium such as NVRAM in the control card 40. Prepared in the storage area.

  The “accumulated consumption level” is a value obtained by individually integrating the consumption levels of the plurality of power semiconductor elements. The cumulative consumption level storage unit 470 includes, for example, an inverter circuit 13 such as an IGBT or FWD (Free Wheel Diode). Cumulative wear levels corresponding to each of the power semiconductor elements to be configured are individually stored.

  Next, various function units included in the wear level monitoring unit 450 will be described.

  The operation state determination unit 451 is a functional unit for determining the operation state of the power conversion device 10. For example, the operation frequency and the carrier frequency set for operating the power conversion device 10, and the output current detection device 41. The operating state of the power conversion device 10 corresponds to any of a plurality of operating patterns based on the average value of the output current detected by the unit in a predetermined period (for example, one determination cycle of the operating state determination unit 451). (The operation pattern corresponding to the operation state of the power converter 10 is specified).

  Specifically, the operation state determination unit 451 refers to the consumption level reference table 460 using the three values of the operation frequency, the carrier frequency, and the average value of the output current in a predetermined period, and the operation state of the power conversion device 10. The operation pattern (one table cell of the consumption level reference table 460, which is a three-dimensional table) is identified.

  The consumption level integration unit 452 is a functional unit for calculating the cumulative consumption level of the power semiconductor elements. For example, the consumption level integration unit 452 uses the operation pattern specified by the operation state determination unit 451 to determine the consumption level of the specific power semiconductor element (specification). One of the table values in the one table cell thus read is read out.

  After that, the consumption level integration unit 452 adds the read consumption level to the cumulative consumption level related to the specific power semiconductor element stored in the cumulative consumption level storage unit 470 and updates the cumulative consumption level.

  Similarly, the wear level integration unit 452 reads the wear level and updates the cumulative wear level for other power semiconductor elements in the power conversion apparatus 10.

  The cumulative consumption level display unit 453 is a functional unit for presenting the cumulative consumption level to the operator. For example, the cumulative consumption level display unit 453 is the cumulative value related to the power semiconductor elements that are most consumed among all the power semiconductor elements in the power conversion device 10. The consumption level (hereinafter, “maximum cumulative consumption level”) is displayed on the display device 43.

  The cumulative consumption level display unit 453 displays the maximum cumulative consumption level in an arbitrary display mode such as numerical display (digital display), bar graph display, or meter display.

  In addition, the cumulative consumption level display unit 453 may display the cumulative consumption level related to each of all the power semiconductor elements in the power conversion device 10 on the display device 43. The cumulative wear level related to the semiconductor element for use may be displayed on the display device 43.

  In addition, the cumulative consumption level display unit 453 displays the remaining life (%) calculated by subtracting the cumulative consumption level (%) from the remaining lifetime (for example, the value 100 (%)) of the power semiconductor element that has been most consumed. Further, the remaining period (number of days) calculated based on the period until the current cumulative consumption level may be displayed), and the cumulative consumption level may be 100%. The remaining number of molding shots that can be executed until the time (for example, calculated based on the number of molding shots that have been executed up to the current cumulative wear level) may be displayed.

  The replacement time notification unit 454 is a functional unit for notifying the operator of the replacement time of the power semiconductor element. For example, the recommended replacement date and time (for example, the current cumulative consumption of the power semiconductor element that has been consumed most). If the current cumulative wear level is 50% and the time elapsed so far is 4 years, the recommended part replacement date is earlier than 4 years later. Or the remaining number of days until the cumulative consumption reaches 100% is displayed on the display device 43.

  In addition, the replacement time notification unit 454 generates an alarm sound from the audio output device 44 when the remaining life of the power semiconductor element that has been consumed most falls below a threshold value, and notifies the operator that the part replacement time has arrived. You may make it tell.

  In addition, the replacement time notification unit 454 may display a message according to the remaining days until the cumulative consumption level reaches 100% on the display device 43, for example, until the cumulative consumption level reaches 100%. When the remaining number of days reaches 100 days, the message “Replacement within 3 months is recommended” is displayed. When the remaining number of days until the cumulative exhaustion level reaches 100% falls below 30 days, “Replace immediately” It is recommended to do this "message.

  Next, referring to FIG. 5, a process in which the power semiconductor element consumption level monitoring system 100 monitors the consumption level of the power semiconductor elements in the power conversion apparatus 10 (hereinafter referred to as “a consumption level monitoring process”). The flow will be described. FIG. 5 is a flowchart showing the flow of the consumption level monitoring process. In the power semiconductor element consumption level monitoring system 100, the output current detection device 41 has a predetermined sampling period (for example, 10 milliseconds). While the value of the output current to be output is sampled and recorded in an output current log (not shown) on the RAM, this consumption level monitoring process is repeatedly executed at a predetermined determination period (for example, 1 second). Shall.

  First, the wear level monitoring unit 450 of the control card 40 acquires the current set values of the operation frequency and the carrier frequency by the operation state determination unit 451, and outputs in a predetermined determination period recorded in the output current log. Calculate the average value of the current.

  Thereafter, the consumption level monitoring unit 450 uses the operation state determination unit 451 to refer to the consumption level reference table 460 using the acquired values of the operation frequency and the carrier frequency and the calculated average value of the output current, and to determine the operation pattern ( (Table cell) is specified (step S1).

  Thereafter, the consumption level monitoring unit 450 reads out the value in the specified table cell by the consumption level integration unit 452, and thereby the power semiconductor element in the power conversion device 10 when the specified operation pattern is executed. Each degree of wear is acquired (step S2).

  After that, the wear level monitoring unit 450 uses the wear level accumulation unit 452 to store the obtained wear level values of the power semiconductor elements in the power conversion apparatus 10 in the cumulative wear level storage unit 470. It adds to the value of the cumulative consumption corresponding to each semiconductor element (step S3).

  After that, the wear level monitoring unit 450 causes the cumulative wear level display unit 453 to display the maximum cumulative wear level (the most consumed level) that is the maximum value among the plurality of cumulative wear level values corresponding to each of the plurality of power semiconductor elements. The value of the advanced consumption semiconductor element is displayed on the display device 43, or the maximum accumulated consumption value already displayed on the display device 43 is updated (step S4). ).

  Thereafter, the wear level monitoring unit 450 compares the maximum cumulative wear level value with a predetermined threshold value (step S5), and if the maximum cumulative wear level value is equal to or greater than the predetermined threshold value (step S5). YES), the replacement time notification unit 454 outputs an alarm sound from the voice output device 44 prompting the replacement of the power semiconductor element that has been most consumed, or displays a text message prompting the replacement on the display device 43. And the operator is notified of the necessity of replacement (step S6).

  When the value of the maximum cumulative consumption level is still less than the predetermined threshold (NO in step S5), the consumption level monitoring unit 450 performs this consumption level monitoring process without prompting the replacement of the power semiconductor element. Terminate.

  With the above configuration, the power semiconductor element consumption level monitoring system 100 recognizes the operation state of the power conversion device 10 that changes according to the use environment of the power conversion device 10 as a combination of pre-registered operation patterns, and performs each operation. The cumulative consumption level of each power semiconductor element is monitored while referring to the consumption level reference table 460 that associates and stores the consumption level of each power semiconductor element when the pattern and each operation pattern are executed. The cumulative consumption level can be monitored more accurately than when the cumulative consumption level is monitored on the assumption that the operation state of the conversion device 10 is unchanged.

  Further, the power semiconductor element consumption level monitoring system 100 does not need to calculate the amount of heat generated in each power semiconductor element based on the value of the output current detected by the output current detection device 41 each time, with a lower calculation load. Cumulative wear level can be monitored.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the power semiconductor element consumption level monitoring system 100 specifies an operation pattern based on three values of an operation frequency, a carrier frequency, and an output current, but the number of registered operation patterns (table cell When the operation pattern that completely matches the three values does not exist, the wear level in the closest operation pattern (table cell) is adopted.

  Alternatively, the power semiconductor element consumption level monitoring system 100 may interpolate between operation patterns (table cells) using a predetermined approximate expression. In this case, the power semiconductor element consumption level monitoring system 100 can monitor the consumption level of each power semiconductor element with higher accuracy.

  Alternatively, the power semiconductor element wear level monitoring system 100 acquires a wear level using an operation pattern (table cell) for an operation state with a high occurrence frequency, and calculates a predetermined function (calculation) for an operation state with a low occurrence frequency. You may make it acquire the wear degree corresponding to those driving | running states using Formula. In this case, the power semiconductor element consumption level monitoring system 100 can monitor the consumption level of each power semiconductor element with higher accuracy while suppressing the calculation load and supporting a wide range of operating conditions.

  The power semiconductor element consumption level monitoring system 100 uses the predetermined function (calculation formula) to calculate the consumption level corresponding to the operation state without using the operation pattern (table cell) for all the operation states. You may make it acquire.

  In the embodiment described above, the power semiconductor element consumption level monitoring system 100 stores the cumulative consumption level corresponding to each of the plurality of power semiconductor elements in the cumulative consumption level storage unit 470. In the case of replacement, only the cumulative wear level corresponding to the replaced power semiconductor element is reset, and the cumulative wear level corresponding to other power semiconductor elements not replaced is maintained as it is. Like that. This is because the cumulative consumption level of other power semiconductor elements that have not been replaced can be continuously monitored.

  In the above-described embodiment, the power semiconductor element wear level monitoring system 100 monitors the power semiconductor element wear level in the inverter mounted on the injection molding machine, but is mounted on a device other than the injection molding machine. The degree of consumption of the power semiconductor element in the semiconductor circuit may be monitored.

  2 ... Ball screw 3 ... Nut 4 ... Pressure plate 5, 6 ... Guide bar 7 ... Bearing 8 ... Load cell 9 ... Injection shaft 10 ... Power conversion device 11. ..Rectifier 12 ... Smoothing circuit 12a ... Voltage detector 13, 13A-13D ... Inverter circuit 20 ... AC power supply 30, 30A-30D ... Motor 35 ... User interface 40- Control card 41, 41A-41D ... Output current detection device 42, 42A-42D ... Rotational speed detection device 43 ... Display device 44 ... Audio output device 50 ... Driver card 51 ... Heating cylinder 51-1 ... Nozzle 52 ... Hopper 53 ... Connecting member 55 ... Load cell amplifier 56 ... Controller DESCRIPTION OF SYMBOLS 7 ... Position detector 58 ... Amplifier 59 ... Screw 100 ... Power semiconductor element consumption degree monitoring system 400 ... Motor speed correction part 450 ... Consumption degree monitoring part 451 ... Operation State determination unit 452 ... consumption level integration unit 453 ... cumulative consumption level display unit 454 ... replacement time notification unit 460 ... consumption level reference table 470 ... cumulative consumption level storage unit

Claims (2)

An injection molding machine comprising a power semiconductor element consumption level monitoring system for monitoring a power semiconductor element consumption level in a power converter,
An operation state determination unit for determining which of the plurality of operation patterns set in advance is the operation state of the power conversion device;
A wear level reference table for storing in advance the wear level of the power semiconductor element when each of the plurality of operation patterns is executed;
A consumption level integration unit that acquires and integrates the consumption level of the power semiconductor element in a predetermined cycle when the operation pattern determined by the operation state determination unit is executed with reference to the consumption level reference table; equipped with a,
The operation state determination unit determines an operation pattern based on an operation frequency and a carrier frequency set for driving the power semiconductor element, and an output current output from the power semiconductor element,
The wear level integration unit uses the wear level acquired in the first cycle as it is, and sets the newly acquired wear level as the wear level integrated value in the previous cycle after the second cycle. Injection molding machine. A power semiconductor element consumption level monitoring system for monitoring a consumption level of a power semiconductor element in a power conversion device,
An operation state determination unit for determining which of the plurality of operation patterns set in advance is the operation state of the power conversion device;
A wear level reference table for storing in advance the wear level of the power semiconductor element when each of the plurality of operation patterns is executed;
A consumption level integration unit that acquires and integrates the consumption level of the power semiconductor element in a predetermined cycle when the operation pattern determined by the operation state determination unit is executed with reference to the consumption level reference table; equipped with a,
The operation state determination unit determines an operation pattern based on an operation frequency and a carrier frequency set for driving the power semiconductor element, and an output current output from the power semiconductor element,
The wear level integration unit uses the wear level acquired in the first cycle as it is, and sets the newly acquired wear level as the wear level integrated value in the previous cycle after the second cycle. Power consumption semiconductor device consumption monitoring system.

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