JP2008011622A - Inverter device, its alternating-current motor diagnosis, and method for representing diagnostic outcome - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverter device having an alternating-current motor diagnosis function and a diagnostic outcome representational function. <P>SOLUTION: The inverter device 20 includes: an inverter circuit 1; current detectors 3, 4 for detecting output current; and an inverter control arithmetic unit 5 for supplying a voltage command of predetermined voltage and frequency. The inverter device drives an alternating-current motor 2. The inverter control arithmetic unit 5 is constructed of: a command setting/status indicating device 6 for indicating operating/abnormal status to the external; a current detection computing unit 8 for arithmetically processing signals from the current detectors 3, 4; a control computing unit 7 for computing a voltage command; a PWM computing unit 9 for outputting a PWM signal based on a voltage command; a measurement commanding device 10 for measuring and computing an electrical constant of the alternating-current motor 2 based on a voltage value, a current value, and the output frequency of voltage; and a measured value analyzer 11 for comparing a measured and computed value with a reference value to diagnoses and analyzes any anomaly. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an inverter apparatus for diagnosing drive and characteristics of an AC motor, an AC motor diagnosis thereof, and a diagnosis result display method.

In the abnormality determination processing of an AC motor by a conventional inverter device, the primary resistance of the AC motor is measured by eliminating an error due to a difference in phase angle, and the AC motor and power conversion means are disconnected, open phase, three-phase unbalance, etc. An abnormality is judged. (For example, see Patent Document 1)
In the AC motor abnormality determination process using a conventional inverter device, primary resistance is measured, and this value is compared with a preset initial value to determine abnormality such as insulation breakdown due to microsurge or the like. ing. (For example, see Patent Document 2)
In FIG. 14, a direct current is supplied to the induction motor 202 by the inverter device 201. At this time, the primary resistance of the induction motor 202 is calculated from the voltage and current detected by the voltage detector 206 and the current detector 207, and decreases from the initial value. In this case, an abnormality due to a decrease in insulation is determined.

In addition, as a method of measuring the electrical constant of the AC motor, there is a method of measuring a primary resistance from a measured value when a DC voltage is applied, or measuring a secondary resistance and a leakage inductance by applying an AC voltage, Many techniques for improving measurement accuracy have been realized (for example, see Patent Document 3).
JP-A-8-33194 (7th page, FIG. 10) JP 2000-262087 A (page 3-8, FIG. 1) Japanese Patent Laid-Open No. 2002-22813 (pages 16-19, FIGS. 4 and 7)

Conventional inverter devices measure the primary resistance value of AC motors and determine abnormalities such as disconnection, phase loss, and three-phase imbalance in AC motors and power conversion means. It is not easy to judge whether the AC motor is good or bad. In addition, abnormalities are identified by a decrease in resistance compared to the initial value of the primary resistance of the AC motor. Therefore, unless the original primary resistance value of the AC motor is known in advance, insulation due to surge voltage or aging There is a problem that the deterioration cannot be determined, and no specific disclosure has been made regarding a method for reporting an abnormality when an abnormality is detected.
Furthermore, since AC motors are robust and can be used for a long period of time, the electrical characteristics of old AC motors are unknown, making it difficult to select applicable inverter devices, and discovering imbalances between impedances of AC motors. It may be difficult.

The present invention has been made in view of such problems, and an object thereof is to provide an inverter device having an AC motor diagnosis function and a diagnosis result display function having the following characteristics.
(1) Measure a plurality of electrical constants such as primary resistance, secondary resistance, and leakage inductance of an AC motor at a plurality of phases.
(2) Compare the measurement result with a reference value, or compare variations between measurement values at different phases.
(3) Based on the above comparison results, a diagnosis of overall deterioration of the AC motor and a characteristic variation between phases are performed.
(4) Based on the above diagnostic results, problems with AC motors are easily diagnosed.
(5) Diagnose whether the combination of inverter and AC motor capacity is appropriate from the above measurement results.
(6) Utilizing the display function of the display device added to the inverter device, display the diagnosis result (abnormal content) appropriately.

In order to solve the above problem, the present invention is configured as follows.
According to the first aspect of the present invention, an inverter circuit that converts a DC voltage into an AC voltage having a variable voltage and a variable frequency by on / off control with a switching element and outputs the AC voltage, and a current output from the inverter circuit are detected. In an inverter device for driving an AC motor including a current detector for driving and an inverter control arithmetic device that performs a process of giving a voltage command of a predetermined voltage and frequency to the inverter circuit, the inverter control arithmetic device is externally provided. When the operation command is received, a command setting / status display device that displays the operation status and abnormal status of the inverter device to the outside, a current detection calculator that performs arithmetic processing on the signal from the current detector, and an output based on the operation command A control arithmetic unit that calculates a voltage command to be output and a signal for performing on / off control of the switching element based on the voltage command A PWM calculator, a measurement commander for measuring and calculating an electrical constant of the AC motor based on a voltage value, a current value, and an output frequency of the voltage, and a measurement calculation value for the electrical constant of the AC motor. It has an AC motor diagnosis function and a diagnosis result display function characterized by comprising a measurement value analyzer that compares with a reference value and diagnoses and analyzes an electrical abnormality of the AC motor.

According to a second aspect of the present invention, in the inverter device of the first aspect, the measurement value analyzer is configured to calculate each amplitude value and phase difference based on a voltage value and a current detection value supplied to the AC motor. Saves the detected value calculator for performing calculation, the measured value calculator for calculating the resistance and inductance based on the output of the detected value calculator, the output of the measured value calculator, and the measurement phase. The command setting / status display device, comprising: a measurement value storage device; and a measurement result evaluation processor for diagnosing an electrical abnormality of the AC motor in comparison with a reference value based on a result stored in the measurement value storage device. Is provided with a state display function for displaying the output of the measurement result evaluation processor.
According to a third aspect of the present invention, in the inverter device according to the first or second aspect, the measurement value analyzer measures a resistance component and an inductance component, which are electrical constants of the AC motor in a predetermined phase, The measurement result is compared with a reference value, and it is determined whether the difference between the two exceeds an allowable value, which is an abnormal state. The command setting / status display device has a function of displaying the output of the measurement value analyzer. It is a thing.

According to a fourth aspect of the present invention, in the inverter device of the first or second aspect, the measurement value analyzer measures a resistance component and an inductance component, which are electrical constants of the AC motor in a plurality of phases, A function that compares the average value of the measurement results with a reference value, determines whether the difference between the two exceeds an allowable value and is in an abnormal state, and the command setting / status display device displays the output of the measurement value analyzer It is equipped with.
According to a fifth aspect of the present invention, in the inverter device according to the fourth aspect, the command setting / status display device uses a direction as a phase axis and a direction orthogonal to the phase axis as a level axis of the measurement result. Is displayed in a two-dimensional graph, and a function for displaying a corresponding constant at a predetermined position of the graph is provided.

The invention according to claim 6 is the inverter device according to claim 1 or 2, wherein the measurement value analyzer measures a resistance component and an inductance component which are electrical constants of the AC motor in a plurality of phases, The command setting / status display device has a function of displaying a measurement result for each phase of the output of the measurement value analyzer.
The invention according to claim 7 is the inverter device according to claim 6, wherein the command setting / status display device has a measurement result with one direction as a phase axis and a direction orthogonal to the phase axis as a level axis of the measurement result. Is displayed in a two-dimensional graph, and a function for displaying a corresponding constant at a predetermined position of the graph is provided.

The invention according to claim 8 is the inverter device according to claim 1 or 2, wherein the measurement value analyzer measures a resistance component and an inductance component, which are electrical constants of the AC motor in a predetermined phase, Determine the rated capacity of the AC motor to be measured based on the measurement result, determine whether the AC motor to be measured can be driven using the inverter device used for measurement, and set the command The status display device has a function of displaying the determination.
The invention according to claim 9 is the inverter device according to claim 1 or 2, wherein the measurement value analyzer measures a resistance component and an inductance component, which are electrical constants of the AC motor in a plurality of phases, Determine the rated capacity of the AC motor to be measured based on the average value of the measurement results, determine whether the AC motor to be measured can be driven using the inverter device used for the measurement, The command setting / status display device has a function of displaying the determination.

  According to a tenth aspect of the present invention, in the inverter device according to the first or second aspect, the measurement value analyzer is used for measurement based on an input electric constant of the AC motor and other rated values. It is determined whether or not the AC motor to be measured can be driven using the inverter device, and the command setting / state display device has a function of executing processing for displaying the determination.

In order to solve the above problem, the present invention is as follows.
According to an eleventh aspect of the present invention, an inverter circuit that converts a DC voltage to a variable voltage / variable frequency AC voltage by an on / off control by a switching element and outputs the AC voltage, and a current output from the inverter circuit are detected. In an AC motor diagnosis of an inverter device for driving an AC motor, and a diagnostic result display method, comprising: a current detector for driving the inverter circuit; and an inverter control arithmetic unit that performs a process of giving a voltage command of a predetermined voltage / frequency to the inverter circuit When the inverter control arithmetic device receives an operation command from the outside by the command setting / status display device, the inverter control operation device displays the operation state or abnormal state of the inverter device to the outside, and the current detection calculator outputs a signal from the current detector. An arithmetic processing is performed, a voltage command to be output based on the operation command is calculated by a control calculator, and the voltage instruction is calculated by a PWM calculator. Based on the above, output a signal for performing on / off control of the switching element, and measure and calculate the electric constant of the AC motor based on the voltage value, the current value, and the output frequency of the voltage by the measurement commander, and measure The value analyzer was used to compare the electric constant of the AC motor with the measured operation value and the reference value to diagnose and analyze the electric abnormality of the AC motor.

According to the first to fourth, sixth and eleventh aspects of the invention, a plurality of electrical constants such as a resistance component and an inductance component of an AC motor are measured at a plurality of phases, and the measurement result is compared with a reference value. By comparing the variation between measured values at different phases and diagnosing the variation in characteristics between phases together with the diagnosis of overall deterioration of the AC motor, defects on the AC motor side in the AC motor drive by the inverter device The problem due to can be easily diagnosed.
In addition, according to the inventions of claims 5 and 7, the abnormality function can be appropriately displayed by utilizing the display function of the display device added to the inverter device, and can be used as a criterion for performing an appropriate measure. .
Furthermore, according to the invention described in claims 8 to 10, it is possible to easily realize the function of determining whether or not the combination of the capacities of the inverter device and the AC motor is appropriate, and the convenience is improved.

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

FIG. 1 is a configuration diagram of an inverter device having a motor diagnosis function of the present invention.
In the figure, reference numeral 1 denotes an inverter circuit that converts a DC voltage VDC into an AC voltage having a variable voltage and a variable frequency by ON / OFF control by a switching element and outputs the AC voltage. Reference numeral 2 denotes an AC motor. In the following embodiments, an induction motor is described as an example. There are induction motors and synchronous motors as types of AC motors. Here, AC motors are described when there is no need to distinguish between them. In the first embodiment, an induction motor is described as an example. However, since FIG. 1 has a configuration common to the induction motor and the synchronous motor, the AC motor 2 is used. Reference numerals 3 and 4 denote current detectors for detecting a current flowing from the inverter circuit 1 to the AC motor, and are provided in two phases of the U phase and the V phase. In the configuration as in this example, since the algebraic sum of the currents flowing in the three phases is zero, the current in the remaining one phase can be measured by providing a current detector in any two phases.

  Reference numeral 5 denotes an inverter control arithmetic unit for causing the inverter circuit 1 to output a voltage necessary for causing the AC motor 2 to perform a desired operation, and includes an element surrounded by an alternate long and short dash line. Reference numeral 6 denotes a command setting / state display device that displays an operation state received from the control calculator 7 when an operation command for the AC motor 2 is set and a command is given to the control calculator 7. Reference numeral 7 denotes a control calculator, which controls the command from the command setting / status display device 6 and the current detection calculator 8 in order to control the inverter circuit 1 to operate according to the command from the command setting / status display device 6. Based on the supplied current detection value and the detection value of the DC bus voltage VDC of the inverter circuit 1 supplied from the PWM calculator 9, a voltage command and an output phase to be output to the inverter circuit 1 are supplied to the PMW calculator 9. Reference numeral 8 denotes a current detection calculator that takes in signals from the U-phase current detector 3 and the V-phase current detector 4, converts them into a data format handled by the control calculator 7, and gives the data to the control calculator 7. Reference numeral 9 denotes a PWM arithmetic unit 9 that gives the inverter circuit 1 a drive signal for turning on / off the switching element of the inverter circuit 1 based on a command from the control arithmetic unit 7 and a DC bus voltage of the inverter circuit 1.

  Further, reference numeral 10 denotes a measurement commanding device, which gives an operation command related to the implementation of the present invention to be described later to the control computing unit 7 when a command for executing a diagnostic function is received from the command setting / status display device 6. . Reference numeral 11 denotes a measurement value analyzer, which is supplied from the control arithmetic unit 7 and the measurement command unit 10 and a voltage command value (or voltage detection value) and its output phase, current detection value, hardware information regarding the inverter model, and Based on the AC motor characteristic value stored in the memory of the control arithmetic unit 7 and the information set by the command setting / status display device 6, the AC motor 2 is diagnosed and the result is given to the command setting / status display device 6. Is.

FIG. 2 is a block diagram showing the configuration of the measurement value analyzer 11 shown in FIG.
Reference numeral 101 denotes a detection value calculator, which calculates the amplitude Vamp and Iamp of each amplitude and the phase difference θvi between vdat and idat based on the voltage value vdat and the current detection value idat supplied to the AC motor 2. It is carried out. When vdat is DC, Vamp = vdat and Iamp = idat may be used. When the voltage value vdat is alternating current, one of the peak value, effective value, and average value of vdat is used. The average value in this case is the average value after taking the absolute value of vdat. The same applies to the current detection value idat. The calculation method of the average value of vdat and idat and the phase difference θvi of vdat and idat can be realized using a known technique such as the method described in Patent Document 3 (Japanese Patent Laid-Open No. 2002-22813). . As the voltage value vdat, either a voltage command value or a voltage detection value may be used. Reference numeral 102 denotes a measurement value calculator, which calculates a resistance component and an inductance component by inputting a voltage value magnitude Vamp, a current value magnitude Iamp, a voltage-current phase difference θvi, and a voltage value vdat frequency fin. It is carried out. Here, since the case of an induction motor will be described as an example, calculation for obtaining a primary resistance R1, an impedance Z, a secondary resistance R2, and a leakage inductance L as electrical constants is performed.

  Reference numeral 103 denotes a measurement value storage device, which is a memory for storing the measurement result and the measurement phase θout at that time. Reference numeral 104 denotes a measurement result / evaluation processor, which is an arithmetic unit that compares the measured value with a reference value corresponding to the measured value, and determines the quality of the AC motor 2 from the difference. The reference value is data of an AC motor prepared for normal operation of the AC motor 2, and is an initial value determined by the model of the AC motor or a normal value measured and set in the past. is there. Further, when measurement is performed for the case where the measurement phase is changed, the data of each phase is compared, and pass / fail is determined by whether or not there is a value greatly different from the average value. The result is output to the command setting / status display device 6 of FIG. 1 and displayed.

The principle for obtaining the measurement result will be described with reference to FIGS.
FIG. 3 shows the characteristics of the induction motor by an electrical model, which is generally called a T1-type equivalent circuit. The primary resistance R1, the leakage inductance L, the mutual inductance M, and the secondary resistance R2 as a secondary circuit portion are expressed by a resistance obtained by dividing the secondary resistance R2 by a slip s. When the input voltage vdat is a direct current, the resistance components of the inductance components L and M are 0, so that the circuit includes only the primary resistor R1 as shown in FIG. 4A, and R1 is obtained from the voltage vdat / current idat. I can do it.
Next, in FIG. 3, when an AC voltage having a frequency fin is applied as vdat in a state where the rotor of the induction motor is not rotated, that is, the condition of slip s = 1, the mutual inductance M is larger than the leakage inductance L. Therefore, the current flowing through the mutual inductance M is negligibly small compared to the current flowing through the secondary resistor R2, and can be represented by a series circuit of resistors R1, R2 and a leakage inductance L as shown in FIG. I can do it. If the voltage vdat at this time is Vamp, the current is Iamp, and the phase difference between vdat and idat is θvi, the combined impedance Z is Vamp / Iamp, the resistance (R1 + R2) is Z · cosθvi, and the inductance L can also be obtained by Z · sinθvi, and the secondary resistance R2 can be obtained by subtracting the value of R1 obtained by applying a DC voltage from (R1 + R2). Here, the magnitudes Vamp and Iamp of vdat and idat may be any of peak values, effective values, and average values after taking absolute values as long as Vamp and Iamp are obtained in the same form.

  In the case of a synchronous motor, since a secondary current does not flow, there is no mutual inductance M and secondary resistance R2. ) Exists. When the synchronous motor is not rotating, it can be considered that ΦΦ = 0 is short-circuited, so that a series circuit of R1 and L is formed. That is, in the diagnostic function described in the present invention, even a synchronous motor can be handled in the same manner as an induction motor.

  FIG. 5 (a) shows a three-phase electrical model in an AC motor. When the three-phase AC voltage applied to the motor is the U-phase, V-phase, and W-phase, the U-phase, V-phase, and W-phase each have a phase of 120 degrees, as shown in the figure. Can be considered as a model diagram in which a circuit Z that interrogates each phase is arranged. In addition, although the figure shown here is a star-shaped connection, here, U phase is set to 0 degree | times of a coordinate axis for description later. Since the electrical model can be replaced with the starter connection in the case of Δ connection, the same can be considered.

  FIG. 5B shows the waveform of the three-phase AC voltage. When the phase (measurement phase) of the voltage output from the inverter device 20 of FIG. 1 is θout, and when θout = 0 °, the U phase is An example in which a peak output voltage is applied will be described. That is, when a voltage is output at a phase of θout = 0 degrees, the voltage applied to the U phase has a peak value, and the (−½) voltage of the U phase is applied to the V phase and the W phase. For convenience, the measurement data of impedance, resistance, and inductance at this time is expressed as U-phase data. Therefore, measurement values for three phases can be obtained by performing measurement at each phase of θout = 0 degrees, 120 degrees, and 240 degrees. Further, by increasing the number of phases to be measured, it is possible to measure the data fluctuation state between phases in more detail.

FIG. 6 is a flowchart showing a process for implementing the embodiment of the present invention using the apparatus shown in FIGS. 1 and 2.
First, the voltage output phase is set to the starting phase θ0 (step 101), and a DC voltage is applied to this phase (step 102). Here, θ0 = 0 degrees is set. In addition, the DC voltage may be applied by giving a voltage command with vdat as a fixed value, and the magnitude is set in a range in which the current flowing through the AC motor does not exceed the allowable current value of the inverter device and the AC motor. .

  Next, the primary resistance R1 is calculated with the voltage value vdat / idat. Next, an alternating voltage is applied to the phase of the measurement phase θout (step 104). AC voltage is, for example, when the frequency of the AC voltage is fin (Hz), the maximum value of the voltage amplitude is Vamp ', and the time is t (seconds), vdat = Vamp' · sin (2π The voltage represented by is given. The magnitudes Vamp and Iamp and the phase difference θvi between them are obtained from the measured voltage vdat and current iamp, and the impedance Z, secondary resistance R2 and inductance L are calculated (step 105). The reference value is compared with the calculation result, and if the difference between the two exceeds the allowable value, it is displayed that there is an abnormality (step 108). As the reference value, a value set in advance in the inverter device for operation of the AC motor to be measured or a value set in advance for comparison before the processing of the present invention is used. The value set in the inverter device in advance for operation is a value prepared in advance as an initial value at the time of manufacturing the inverter, or a value used for the operation of the AC motor before the present invention is carried out. The values set for comparison before the processing of the present invention were newly set based on separately provided information such as AC motor design documents and test reports when performing the processing of the present invention. Value.

  FIG. 7 shows a process when measuring a plurality of phases by changing the phase to be measured in the process of FIG. 6 in order to diagnose the variation in the electrical characteristics of the AC motor due to the phase. The voltage application method and measurement method (steps 111 to 115) are the same as the corresponding processes (steps 101 to 105) shown in FIG. After the measurement at the first phase, there is a process for determining whether the measurement at the predetermined phase has been completed. If it has not been completed, the process proceeds to a process for updating the measurement phase θout, and if completed, the process proceeds to a determination process (Step 116). Here, the update process of the measurement phase θout is performed by a process of adding phases by θinc (step 117). θinc may be an arbitrary value. The smaller the value of θinc is, the more detailed diagnosis is possible, such as characteristic fluctuations in the middle. When θout is completed for one phase rotation (0 ° to 360 °), determination processing is performed (step 118). Compare the measured values at each phase and compare the reference value with each measured value or the average value of the measured values in the same way as in Fig. 6. If there is data that exceeds the allowable range, it is displayed as abnormal. To do.

   FIG. 8 specifically shows the diagnosis result by displaying the size of the measurement data in each phase in the processing of FIG. The measurement method (steps 121 to 127) in FIG. 8 is the same as the corresponding processing (steps 111 to 117) in FIG. As a process of the measurement result, a process of displaying the magnitude of the measurement value for each phase as a level is performed (step 128).

FIG. 9 shows a display method of the diagnosis result.
FIG. 9 (a) shows the display method of the diagnosis results of FIGS. 6 and 7 on a display device using four 7-segment LEDs, and an error code is assigned according to the content of the abnormality. Display as shown in the figure. In the case of the processing of FIG. 7, an error code is assigned so that it can be identified which phase is abnormal. When the number of LEDs is small, it can be handled by using only numbers, and when the number of LEDs is large, the codes can be classified more easily. When an LCD is used as the display device, the characters can be displayed in more detail as words, so that the contents of the error code can be displayed more easily.

  FIG. 9B shows a case where the diagnosis result of FIG. 7 is displayed using four 7-segment LEDs, and the leftmost digit (D) indicates items of the displayed result (impedance Z, resistance R1, inductance L, etc.), and the remaining three digits of vertical display are assigned to the phases to indicate which phase data is abnormal. In this case as well, more detailed results can be displayed when the number of display digits of the LED is large or by using an LCD.

FIG. 9C shows a method of displaying the diagnosis result of FIG. 8 with four 7-segment LEDs. Similarly to FIG. 9 (b), it is divided into a part indicating the measurement item and a part indicating the phase data, and the size of the measurement result is displayed as shown in the figure. This is indicated by the segment position.
FIG. 9D shows a case in which the result of FIG. 8 is displayed using an LCD display device. As shown in the figure, the displayed items can be displayed in characters, and the magnitude relationship of the measurement results for each phase is shown. It is possible to display in more detail than the LED.

  FIG. 10 is a process for determining whether or not the AC motor to be measured can be driven by the inverter device used for the measurement based on the AC motor data measured in the same manner as the process of FIG. Since the accuracy and resolution of the current detector of the inverter device are affected, in order to operate the AC motor optimally with the inverter device, it is necessary to use an inverter device with a capacity corresponding to the capacity of the AC motor, and perform the determination The process of the inverter apparatus which has a function is shown. The measurement process (steps 201 to 208) is the same as the corresponding process (steps 101 to 108) in FIG. This measurement result is compared with a reference value corresponding to the specified capacity, and if the difference between the two is within a predetermined range, it is determined that driving is possible, and if not, driving is not possible (step 208), and the result is displayed. It is displayed on the device (step 209).

  FIG. 11 shows the determination method in step 208 described above. Data 301 for each AC motor capacity corresponding to the capacity of the inverter device is stored in advance in a memory provided in the control arithmetic unit 7 of the inverter device of FIG. Using this data 301 as a reference value, the measured value 302 measured by the method described in the first and second embodiments is compared in the AC motor capacity determination processing 303 to determine the AC motor capacity. As shown in FIG. 1, a signal of hardware information from the inverter unit is input to the control arithmetic unit 7 from the inverter circuit 1 and the capacity of the AC motor is the capacity of the inverter device. The capacity of the inverter device 20 is determined based on the hardware information signal. The AC motor capacity determined in the above procedure is compared with the capacity of the inverter device, and it is determined whether or not the AC motor falls within a capacity within a range driven by the inverter. The determination is made by setting a capacity within a predetermined range with respect to the capacity of the inverter device and whether the capacity of the AC motor is within the range. This predetermined range is an element that is determined individually for each device in consideration of the device specifications, considering characteristics from the accuracy of the current detector used in the inverter device.

  FIG. 12 shows determination using measurement data obtained by measuring a plurality of phases in the process of FIG. The measurement process (steps 211 to 217) is the same as the corresponding process (steps 111 to 117) in FIG. Using the average value of the measurement values measured at each phase as the measurement results used for the determination, the possibility of driving is determined by the same method as in step 208 of FIG. 10 (step 218), and the result is displayed (step 219).

  FIG. 13 is a diagram in which a reference value is separately set as a criterion for determining the AC motor capacity. When there is data described on the nameplate attached to the AC motor or data described in the test report of the AC motor, this value is input (step 220), and this value is used instead of the measured value of FIG. Then, the AC motor capacity is determined, whether or not the target AC motor can be driven by the inverter device being used is determined (step 228), and the result is displayed (step 229).

  As described above, in the present invention, the primary resistance, the secondary resistance, and the leakage inductance in each phase are measured, the variation due to each phase is compared, and an abnormality is determined using the result, and the inverter device and the AC motor And a display means for accurately displaying the determination result.

  By applying the present invention, it is possible to measure the electrical characteristics of an AC motor using an inverter device, determine whether there is an abnormality, and determine whether the capacity of the inverter device and the AC motor is compatible. Therefore, even if the AC motor has been left unattended for a long time, it can be determined whether or not it can be used, and can be applied to the use of materials effectively.

The block diagram of the inverter apparatus which applies the process of the Example of this invention 1 is a block diagram of a measurement value analyzer in the inverter device of FIG. T1 type equivalent circuit diagram of an induction motor for explaining the principle of the present invention An equivalent circuit diagram of an induction motor under a predetermined condition for illustrating the principle of the present invention Model diagram and voltage waveform diagram in three-phase coordinates 1 is a flowchart showing a first embodiment of the present invention. Flow chart showing a second embodiment of the present invention Flow chart showing a third embodiment of the present invention Flow chart showing a fourth embodiment of the present invention. Flow chart showing a fifth embodiment of the present invention. Explanatory drawing of the determination method in 5th Example of this invention Flow chart showing the sixth embodiment of the present invention Flow chart showing a seventh embodiment of the present invention Representative figure of conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inverter circuit 2 AC motor 3 U-phase current detector 4 V-phase current detector 5 Inverter control arithmetic unit 6 Command setting and status display unit 7 Control arithmetic unit 8 Current detection arithmetic unit 9 PWM arithmetic unit 10 Measuring command unit 11 Measurement Value analyzer 20 Inverter device 101 Detected value calculator
102 Measurement Value Calculator 103 Measurement Value Storage Device 104 Measurement Result / Evaluation Processor 201 Inverter Device 202 Electric Motor 203 Converter 204 Smoothing Capacitor 205 Inverse Conversion Unit 206 Voltage Detector 207 Current Detector 208 Primary Resistance Calculator 209 Memory 210 Comparator 211 Display 301 Data of AC motor with built-in inverter memory 302 Measured value 303 AC motor capacity determination processing 304 Inverter model information reading processing 305 Drive availability determination processing

Claims (11)

Inverter circuit for converting DC voltage to ON / OFF control by switching element to convert to AC voltage of variable voltage / variable frequency and outputting, current detector for detecting current output from inverter circuit, and inverter In an inverter device that drives an AC motor including an inverter control arithmetic device that performs processing for giving a voltage command of a predetermined voltage and frequency to a circuit,
The inverter control arithmetic device is a command setting / state display device that displays an operation state and an abnormal state of the inverter device to the outside when receiving an operation command from the outside,
A current detection calculator for calculating a signal from the current detector;
A control calculator for calculating a voltage command to be output based on the operation command;
A PWM calculator that outputs a signal for performing on / off control of the switching element based on the voltage command;
A measurement commander for measuring and calculating an electrical constant of the AC motor based on the voltage value, the current value, and the output frequency of the voltage;
AC motor diagnostic function characterized in that it comprises a measured value analyzer that compares the measured electric value of the AC motor with a measured calculation value and a reference value, and diagnoses and analyzes an electrical abnormality of the AC motor. And an inverter device having a diagnostic result display function. The measurement value analyzer is a voltage value supplied to the AC motor, and a detection value calculator that calculates the amplitude value and phase difference based on the current detection value;
Based on the output of the detection value calculator, a resistance value and a measurement value calculator for calculating the inductance, and
A measurement value storage device for storing the output of the measurement value calculator and the measurement phase;
Based on the result stored in the measurement value storage device, comprising a measurement result evaluation processor for diagnosing electrical abnormality of the AC motor in comparison with the reference value,
2. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a state display function for displaying an output of the measurement result evaluation processor. . The measurement value analyzer measures the resistance component and the inductance component, which are electrical constants of the AC motor in a predetermined phase, compares the measurement result with a reference value, and the difference between the two exceeds an allowable value and is abnormal. Determine if it is in a state,
3. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a function of displaying an output of the measurement value analyzer. The measurement value analyzer measures the resistance component and the inductance component, which are electrical constants of the AC motor in a plurality of phases, compares the average value of the measurement result with a reference value, and the difference between the two values indicates an allowable value. Judging whether it is abnormal condition beyond
3. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a function of displaying an output of the measurement value analyzer.   The command setting / status display device displays a measurement result in a two-dimensional graph with one direction as a phase axis, a direction orthogonal to the phase axis as a level axis of the measurement result, and a corresponding constant at a predetermined position of the graph. 5. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 4, further comprising a function of displaying. The measurement value analyzer measures a resistance component and an inductance component, which are electrical constants of an AC motor in a plurality of phases,
3. The AC motor diagnosis function according to claim 1 or 2, wherein the command setting / state display device has a function of displaying a measurement result for each phase of an output of the measurement value analyzer. An inverter device having a display function.   The command setting / status display device displays a measurement result in a two-dimensional graph with one direction as a phase axis, a direction orthogonal to the phase axis as a level axis of the measurement result, and a corresponding constant at a predetermined position of the graph. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 6, further comprising a display function. The measurement value analyzer measures the resistance component and the inductance component, which are electrical constants of the AC motor in a predetermined phase, determines the rated capacity of the AC motor to be measured based on the measurement result, and performs the measurement. Determine whether the AC motor to be measured can be driven using the inverter device being used,
3. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a function of displaying the determination. The measurement value analyzer measures a resistance component and an inductance component which are electrical constants of the AC motor in a plurality of phases, and determines a rated capacity of the AC motor to be measured based on an average value of the measurement results. , Determine whether it is possible to drive the AC motor to be measured using the inverter device used for measurement,
3. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a function of displaying the determination. Whether the measurement value analyzer can drive the AC motor to be measured using the inverter device used for the measurement based on the electrical constant of the AC motor input and other rated values. Determine
3. The inverter apparatus having an AC motor diagnosis function and a diagnosis result display function according to claim 1, wherein the command setting / state display device has a function of executing a process of displaying the determination. Inverter circuit for converting DC voltage to ON / OFF control by switching element to convert to AC voltage of variable voltage / variable frequency and outputting, current detector for detecting current output from inverter circuit, and inverter In an AC motor diagnosis of an inverter device that drives an AC motor provided with an inverter control arithmetic device that performs processing for giving a voltage command of a predetermined voltage and frequency to a circuit, and a diagnostic result display method,
When the inverter control arithmetic device receives an external operation command from the command setting / status display device, the inverter control operation device displays the operation state or abnormal state of the inverter device to the outside, and the current detection calculator calculates the signal from the current detector. Processing, calculating a voltage command to be output based on the operation command by the control calculator, outputting a signal for performing on / off control of the switching element based on the voltage command by the PWM calculator, Based on the voltage value, current value, and output frequency of the voltage, the electric constant of the AC motor is measured and calculated, and the electric constant of the AC motor is measured and compared with the reference value by the measurement value analyzer. An AC motor diagnosis of an inverter device and a diagnostic result display method characterized by diagnosing and analyzing an electrical abnormality of the AC motor.

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