JP6580311B2 - Vacuum pump and operating method thereof - Google Patents

Description

  The present invention relates to a vacuum pump that sucks gas from a sealed container such as a vacuum chamber, and more particularly to a vacuum pump having an inverter device having a protection function for avoiding a failure due to an overvoltage and / or overcurrent.

  Dry vacuum pumps are widely used as semiconductor device manufacturing equipment. A semiconductor device manufacturing process includes a process of processing a product in a vacuum space, and a dry vacuum pump is used to form the vacuum space.

  In dry vacuum pumps, it is becoming common to perform motor control with an inverter device for the purpose of outputting a desired torque or changing the operation speed in order to save energy or control the pressure in a vacuum space. . Some inverter devices have a protection function for protecting themselves in order to avoid failures due to errors such as overvoltage and / or overcurrent. This type of inverter device is configured such that when an error is detected, a protection function is activated to stop its operation.

JP 2010-127107 A JP 2011-89428 A

  However, if the dry vacuum pump suddenly stops operating during the production of the semiconductor device, the pressure in the vacuum space increases, causing damage to the product (semiconductor device) being produced and generating a defective product.

  Therefore, an object of the present invention is to provide a vacuum pump that can reduce the frequency of operation stop caused by the occurrence of an error, and an operation method thereof.

In order to achieve the above-described object, a first aspect of the present invention includes a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, A control device for controlling the inverter device, and the inverter device stops its own operation when an error due to overvoltage or overcurrent occurs, and the control device generates a predetermined error. If the condition is satisfied, the operation of the pump module is continued by restarting the inverter device before the motor completely stops .

A first reference example of the present invention includes a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, a timer that measures time, and the inverter The inverter device stops its operation when an error due to overvoltage or overcurrent occurs, and the control device is generated within a predetermined period. An error cancel signal for canceling the error is transmitted to the inverter device, and when the inverter device receives the error cancel signal, the inverter device operates itself when the error occurs within the predetermined period. The vacuum pump is characterized in that the operation of the pump module is continued without stopping the operation.

A second reference example of the present invention includes a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, and a control device that controls the inverter device; The inverter device stops its operation when an error occurs, and the control device restarts the inverter device immediately after the operation of the inverter device stops, thereby the pump module The vacuum pump is characterized in that when the number of errors occurring within a set time reaches a predetermined threshold value, the inverter device is not restarted.

According to a second aspect of the present invention, there is provided a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, and a control device that controls the inverter device. When an error caused by overvoltage or overcurrent occurs, the operation of the inverter device is stopped, and if the occurrence of the error satisfies a predetermined condition , by restarting the pre Symbol inverter device, a method of operating a vacuum pump, characterized in that to continue the operation of the pump module.

A third reference example of the present invention includes a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, a timer that measures time, and the inverter A vacuum pump operation method comprising a control device for controlling the device, and when an error due to overvoltage or overcurrent occurs, the operation of the inverter device is stopped and within a predetermined period. An error cancel signal for canceling the generated error is transmitted to the inverter device, and the operation of the inverter device is not stopped when the error occurs within the predetermined period. The operation method of the vacuum pump is characterized in that the operation is continued.

A fourth reference example of the present invention includes a pump module that exhausts gas, a motor that drives the pump module, an inverter device that supplies AC power of variable frequency to the motor, and a control device that controls the inverter device; When an error occurs, the operation of the inverter device is stopped, and the inverter device is immediately restarted after the operation of the inverter device is stopped. The operation of the vacuum pump is characterized in that the operation of the module is continued and the inverter device is not restarted when the number of errors occurring within a set time reaches a predetermined threshold value.

According to the first and second aspects of the present invention, when an error occurs under a predetermined condition, the inverter device is restarted. This predetermined condition is an error generation condition that is expected to prevent the inverter device from failing even if the operation of the inverter device is continued. By such error monitoring control, the frequency of pump operation stoppage due to the occurrence of an error can be reduced.

According to the first and third reference examples of the present invention, when an error occurs within a predetermined period, the error is automatically canceled and the inverter device is not stopped. By such error monitoring control, the frequency of pump operation stoppage due to the occurrence of an error can be reduced.

According to the second and fourth reference examples of the present invention, as long as the number of errors that have occurred within the set time does not reach a predetermined threshold value, even if the operation of the inverter device stops due to the occurrence of an error, the inverter device Will be restarted immediately. By such error monitoring control, the frequency of pump operation stoppage due to the occurrence of an error can be reduced. Furthermore, since any one of the plurality of timers starts measuring time each time an error occurs, the control device can quickly and reliably detect that the error has occurred frequently.

It is a mimetic diagram showing a vacuum pump concerning one embodiment of the present invention. It is a schematic diagram of an inverter apparatus. It is a graph which shows the change of the rotational speed of a motor when an error generate | occur | produces when the motor is idling. It is a graph which shows the change of the rotational speed of a motor when an error generate | occur | produces when the inverter apparatus decelerates the motor according to the instruction | command from a control apparatus. It is a figure for demonstrating operation | movement of the counter which counts the frequency | count of an error, and the timer which measures monitoring time. It is a graph explaining that an inverter apparatus is in error cancellation mode in a predetermined period. It is a schematic diagram which shows the vacuum pump which concerns on other embodiment of this invention. It is a time chart explaining operation | movement of the timer when an error occurs at a low frequency. It is a time chart explaining operation | movement of a timer when an error occurs with high frequency. It is a time chart explaining the method of determining whether the frequency | count of the error which generate | occur | produced within the setting time reached the predetermined threshold value using one timer.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic diagram showing a vacuum pump according to an embodiment of the present invention. As shown in FIG. 1, the vacuum pump includes a pump module 1 that exhausts gas, a motor 2 that drives the pump module 1, an inverter device 5 that supplies AC power of variable frequency to the motor 2, and an inverter device 5. And a control device 7 for controlling.

  The pump module 1 is connected to a sealed container 8 such as a vacuum chamber, and sucks the gas in the sealed container 8 to form a vacuum in the sealed container 8. As the pump module 1, a dry pump module that does not use oil is formed in a gas flow path formed therein. A vacuum pump equipped with such a dry pump module is generally called a dry vacuum pump, and is widely used in the manufacture of semiconductor devices.

  FIG. 2 is a schematic diagram of the inverter device 5. As shown in FIG. 2, the inverter device 5 includes a converter unit 11, a smoothing capacitor 15, an inverter unit 12, a gate driver 13, and an inverter control unit 16. The converter unit 11 has a rectifier circuit therein, and is configured to convert three-phase AC power supplied from the power supply source 9 into DC power. The smoothing capacitor 15 is provided to smooth the converted DC power.

  The inverter unit 12 includes a switching element such as an IGBT (insulated gate bipolar transistor), and generates three-phase AC power from the smoothed DC power. The gate driver 13 generates a gate drive signal for opening and closing each switching element of the inverter unit 12. The switching element of the inverter unit 12 is driven in accordance with a gate drive signal from the gate driver 13, whereby the inverter unit 12 outputs variable-frequency AC power.

  The current measuring device 20 measures the three-phase current output from the inverter unit 12 and sends the measured value of the three-phase current to the inverter control unit 16. The inverter control unit 16 controls the AC power output from the inverter unit 12 based on the measurement value sent from the current measuring device 20 and the speed command value sent from the control device 7. That is, the inverter control unit 16 receives a speed command value from a higher-order pump controller (not shown) and generates a PWM signal based on the measured value of the three-phase current. This PWM signal is sent to the gate driver 13. The gate driver 13 generates a gate drive signal for driving the switching element of the inverter unit 12 based on the PWM signal. The switching element of the inverter unit 12 is driven in accordance with a gate drive signal from the gate driver 13, whereby the inverter unit 12 outputs variable frequency AC power to the motor 2.

  The inverter device 5 has a protection function for protecting itself from failure when errors such as overvoltage and overcurrent occur. More specifically, when an error occurs, the inverter device 5 is configured to stop its operation. The error is roughly classified into an overvoltage error (that is, an excessive voltage is applied to the inverter device 5) and an overcurrent error (that is, an excessive current flows through the inverter device 5).

  When the DC power input to the converter unit 11 increases, the smoothing capacitor 15 in the inverter device 5 and each switching element of the inverter unit 12 may be destroyed. Therefore, the inverter device 5 is configured to monitor the DC voltage of the converter unit 11, and when the DC voltage is equal to or higher than a preset value, the inverter device 5 is configured to stop its operation.

  Possible causes for the DC voltage of the converter unit 11 to rise include abnormalities in the power supply source 9 and inverter control irregularities. Hereinafter, an overvoltage error caused by an abnormality of the power supply source 9 is referred to as error 1, and an overvoltage error caused by inverter control irregularity is referred to as error 2.

  Error 1 is caused by an abnormality in the power supply source 9 that supplies AC power to the inverter device 5. Error 1 can be caused by various causes. When the error 1 occurs, the input voltage to the inverter device 5 increases, so that the inverter device 5 may break down. Therefore, in this case, the inverter device 5 immediately stops its operation.

  Error 2 is likely to occur when the motor 2 and the pump module 1 that are rotating (ie free-running) only with inertial force are restarted after an instantaneous power failure. When a momentary power failure occurs, the power output of the inverter device 5 automatically stops (that is, the inverter device 5 cannot output power because no power is input). Since the time length of the instantaneous power failure is usually within 1 second, the motor 2 continues to rotate due to inertia during the momentary power failure, but the rotation speed of the motor 2 gradually increases due to a bearing loss or the like. descend.

  When the power is restored, the inverter device 5 measures the current rotational speed of the motor 2 that is free-running, and the inverter device 5 starts outputting AC power having a frequency synchronized with the rotational speed of the motor 2. At this time, when the inverter device 5 outputs AC power having a frequency lower than the frequency corresponding to the rotational speed of the motor 2, the inverter device 5 actively decelerates the motor 2, and the power of the motor 2 is regenerated energy. To the inverter device 5. As a result, the voltage in the inverter device 5 rises and an overvoltage is generated.

  If the power failure continues for a long time, the motor 2 is completely stopped. Therefore, the operation for starting the inverter device 5 after a long power failure is no different from the normal start operation, and in this case, the above-described error does not occur.

  Error 2 is also likely to occur when the inverter device 5 decelerates the motor 2 in accordance with a command from the control device 7. For example, when the vacuum pump shifts from the normal operation mode to the idle operation mode, the control device 7 instructs the inverter device 5 to reduce the rotation speed of the motor 2. If the rotational speed of the motor 2 is positively reduced in this way, the power of the motor 2 may return to the inverter device 5 as regenerative energy. As a result, the voltage in the inverter device 5 rises and an overvoltage may occur.

  In addition to overvoltage, overcurrent can also cause failure of the inverter device 5. That is, when a large current flows through the inverter device 5, the switching element inside the inverter device 5 may be destroyed. Therefore, the inverter device 5 is configured to monitor the output current of the inverter unit 12, and when the output current is equal to or greater than a preset value, the inverter device 5 is configured to stop its operation.

  As the cause of the overcurrent, the inverter control turbulence and the failure of the motor 2 can be considered. Hereinafter, an overcurrent error caused by inverter control turbulence is referred to as error 3, and an overcurrent error caused by motor 2 failure is referred to as error 4.

  Error 3 is the same as error 2, when the motor 2 that is rotating only by the inertial force is restarted after an instantaneous power failure, or when the inverter device 5 starts the motor 2 in accordance with a command from the control device 7. This is likely to occur when decelerating. For example, when the inverter device 5 is restarted after an instantaneous power failure, if the frequency of the AC power output from the inverter device 5 is significantly different from the actual rotational speed of the motor 2, an overcurrent is caused by the inverter control irregularity. Flows. In particular, when sensing of the rotor position of the motor 2 fails, a voltage is applied to the motor 2 at an inappropriate timing, resulting in an overcurrent. Reasons for failure in sensing the rotor position include noise superimposed on the detected current of the motor 2, and the load of the pump module 1 changes abruptly and the rotational speed of the motor 2 changes abruptly.

  Further, error 3 is likely to occur when the pump module 1 (and the motor 2) is idling. The idle operation is an operation in which the motor 2 is rotated at an idle speed lower than the rated speed of the motor 2 for the purpose of energy saving. For example, in idle operation, the motor 2 is rotated at a speed that is 10% of the rated speed of the motor 2. The inverter device 5 is adjusted so that appropriate speed control can be performed when the motor 2 is rotating at the rated speed. If the difference between the idle speed and the rated speed is large, the control operation of the inverter control unit 16 becomes unstable, and an overcurrent may flow.

  Error 4 is an error resulting from the failure of the motor 2. For this reason, when the error 4 occurs, the operation of the inverter device 5 must be stopped immediately, and the motor 2 must be repaired or replaced.

  As described above, the error of the inverter device 5 is roughly divided into an overvoltage error and an overcurrent error. Further, the overvoltage error is divided into error 1 due to abnormality of the power supply source 9 and error 2 due to inverter control turbulence. Overcurrent error is error 3 due to inverter control turbulence and motor 2. It is divided into error 4 resulting from the failure. When these errors 1 to 4 occur, the inverter device 5 stops its operation and transmits an error signal to the control device 7.

  Of the four errors 1 to 4, errors 1 and 4 are serious errors. In other words, if the operation of the inverter device 5 is continued after the errors 1 and 4 have occurred, the inverter device 5 may break down. Therefore, when errors 1 and 4 occur, it is necessary to stop the operation of the inverter device 5.

  On the other hand, errors 2 and 3 are relatively minor errors. For example, if the rotational speed of the motor 2 rotating by inertia decreases and the regenerative energy decreases, overvoltage and overcurrent do not occur. Even if the rotor position sensing fails, the rotor position sensing may be performed correctly at the next moment. These errors 2 and 3 are not caused by the failure of the inverter device 5 itself, but are caused by the disturbance of the control of the inverter device 5, and therefore it may not be necessary to stop the operation of the inverter device 5.

  Therefore, in order to avoid frequent shutdown of the vacuum pump due to the occurrence of an error, the control device 7 is configured to immediately restart the inverter device 5 when the errors 2 and 3 occur.

When any one of the errors 1 to 4 occurs, an error signal is sent from the inverter device 5 to the control device 7. Therefore, the control device 7 can detect the occurrence of an error by receiving this error signal. When the occurrence of the error satisfies a predetermined condition, the control device 7 determines that the error is the error 2 or the error 3, and restarts the inverter device 5. The predetermined conditions are the following three conditions.
Condition 1: An error occurs within a predetermined time (within 10 seconds, preferably within 5 seconds, more preferably within 2 seconds) after a power failure (instantaneous power failure) is recovered and power supply is resumed. What you did.
Condition 2: An error occurs within a predetermined time (within 10 seconds, preferably within about 5 seconds, more preferably within 2 seconds) from the time point when the inverter device 5 starts to decelerate the motor 2 in accordance with a command from the control device 7 What you did.
Condition 3: An error occurred when the inverter device 5 is rotating the motor 2 at an idle speed lower than its rated speed (less than 50% of the rated speed, preferably less than 30%, more preferably less than 10%). thing.

  The control device 7 restarts the inverter device 5 when the occurrence of the error satisfies any one of the condition 1, the condition 2, and the condition 3. On the other hand, when the occurrence of the error does not satisfy any of the conditions 1, 2 and 3, the error is considered to be the errors 1 and 4 described above, so the control device 7 restarts the inverter device 5. Do not start. The reason why the conditions 1 to 3 are set is that, as described above, the errors 2 and 3 are caused when the inverter device 5 is restarted immediately after the momentary power failure, when the motor 2 is actively decelerated, and This is because it is likely to occur when 2 is idling.

  FIG. 3 is a graph showing changes in the rotational speed of the motor 2 when an error occurs while the motor 2 is idling. As shown in FIG. 3, when an error occurs while the motor 2 is rotating at the idle speed, the inverter device 5 sends an error signal to the control device 7 and at the same time stops its operation. Since the occurrence of the error satisfies the condition 3, the control device 7 restarts the inverter device 5. The motor 2 rotates again before it stops completely and continues to drive the pump module 1. Thus, even if an error occurs, the inverter device 5 continues its operation, so that the pump module 1 can continue to evacuate the sealed container 8.

  FIG. 4 is a graph showing changes in the rotational speed of the motor 2 when an error occurs when the inverter device 5 decelerates the motor 2 in accordance with a command from the control device 7. As shown in FIG. 4, if an error occurs while the inverter device 5 is decelerating the motor 2, the inverter device 5 sends an error signal to the control device 7 and at the same time stops its operation. The control device 7 restarts the inverter device 5 because the occurrence of the error satisfies the condition 2. As shown in FIG. 4, when the error occurs again within a predetermined time (within 10 seconds, preferably within about 5 seconds, more preferably within 2 seconds) after the inverter device 5 restarts, the control device 7 May restart the inverter device 5 again.

  Errors 2 and 3 are relatively minor errors, but if they occur frequently, serious failures may occur. Therefore, the control device 7 determines whether to continue or stop the operation of the inverter device 5 based on the occurrence frequency of the errors 2 and 3. More specifically, the control device 7 counts the number of times that an error (error 2 or error 3) has occurred, and restarts the inverter device 5 when the counted number reaches a predetermined threshold value. It is configured not to let you.

  As shown in FIG. 1, the control device 7 includes a counter 22 that counts the number of errors and a timer 23 that measures a monitoring time. The control device 7 resets the counted number to 0 when no error occurs within the predetermined monitoring time. This is because an error does not occur within a predetermined monitoring time because the occurrence frequency of errors 2 and 3 is considered to be low.

  FIG. 5 is a diagram for explaining the operation of the counter 22 for counting the number of errors and the timer 23 for measuring the monitoring time. When an error (error 2 or error 3) occurs, the counter 22 counts the number of occurrences of the error, and the timer 23 starts simultaneously. Next, when an error (error 2 or error 3) occurs, the counter 22 counts the number of occurrences of the error, and at the same time, the timer 23 is reset to 0 and starts again. If no error has occurred for a predetermined monitoring time (10 seconds in FIG. 5), the counted number of errors is reset to zero.

  When an error (error 2 or error 3) occurs again, the counter 22 counts the number of occurrences of the error from 1, and the timer 23 starts at the same time. As a result of repeating the counting of the number of errors and the reset / start of the timer 23, when the counted number of errors reaches a predetermined threshold value (three times in FIG. 5), the control device 7 Even if an error occurs, the inverter device 5 is not restarted. As a result, the supply of power from the inverter device 5 to the motor 2 is stopped, and the pump module 1 is also stopped accordingly.

  If an error occurs before a predetermined monitoring time elapses, it means that the frequency of error occurrence is high. Therefore, in such a case, the control device 7 can protect the inverter device 5 from failure by not restarting the inverter device 5.

  Next, another embodiment of the present invention will be described. The configuration and operation of this embodiment that are not specifically described are the same as those of the above-described embodiment, and redundant description thereof is omitted. In the present embodiment, the control device 7 is configured to transmit an error release signal for releasing an error that has occurred within a predetermined period to the inverter device 5, and the inverter device 5 receives the error release signal. When an error occurs within the predetermined period, the operation is not stopped.

The predetermined time is the following three periods.
Period 1: A period until a predetermined time (10 seconds, preferably 5 seconds, more preferably 2 seconds) elapses after the power failure is restored and the supply of power is resumed.
Period 2: A period until a predetermined time (10 seconds, preferably 5 seconds, more preferably 2 seconds) elapses after the inverter device 5 starts decelerating the motor 2 in accordance with a command from the control device 7.
Period 3: A period during which the inverter device 5 rotates the motor 2 at an idle speed lower than its rated speed (less than 50% of the rated speed, preferably less than 30%, more preferably less than 10%).

  FIG. 6 is a graph for explaining that the inverter device 5 is in the error canceling mode during the periods 1, 2, and 3. The control device 7 transmits an error release signal to the inverter device 5 at the start points of the above-described periods 1, 2, and 3. The inverter device 5 receives this error cancel signal and cancels an error occurring in the periods 1, 2, and 3. According to the present embodiment, since the error is canceled, the inverter device 5 does not stop. Therefore, a drop in the rotation speed of the motor 2 can be avoided, and the pump module 1 can maintain the vacuum pressure in the sealed container 8.

  An error that occurs during the above-described periods 1, 2, and 3 is considered to be error 2 or error 3 described above. On the other hand, an error that occurs outside the above-described periods 1, 2, and 3 is considered to be error 1 or error 4 described above. The error cancel signal sets the inverter device 5 in the error cancel mode only during the periods 1, 2, and 3. Therefore, if an error occurs in other than the periods 1, 2, 3, the inverter device 5 stops its operation. .

  Also in this embodiment, whenever an error occurs, the inverter device 5 transmits an error signal to the control device 7. As in the above-described embodiment, the control device 7 counts the number of times an error (error 2 or error 3) has occurred, and counts if no error has occurred within a predetermined monitoring time (for example, 10 seconds). When the counted number of times reaches a predetermined threshold, the error canceling signal is not transmitted to the inverter device 5. Therefore, if an error occurs after the counted number of times reaches a predetermined threshold, the error is not canceled and the inverter device 5 stops its operation.

  FIG. 7 is a schematic view showing a vacuum pump according to another embodiment of the present invention. The configuration and operation of the present embodiment that are not particularly described are the same as those of the embodiment shown in FIG. The inverter device 5 stops its own operation when an error occurs, and the control device 7 is configured to restart the inverter device 5 after the operation of the inverter device 5 stops. The types of errors include all types of errors including errors due to overcurrent and errors due to overvoltage. That is, regardless of the type of error, when an error occurs, the inverter device 5 stops its own operation.

  As a result of the error, even if the operation of the inverter device 5 is stopped, the control device 7 restarts the inverter device 5 immediately. Therefore, a drop in the rotation speed of the motor 2 is avoided, and the pump module 1 can maintain the vacuum pressure in the sealed container 8. However, if the inverter device 5 is forcibly restarted when errors frequently occur, the inverter device 5 may break down. Therefore, the control device 7 is configured not to restart the inverter device 5 when the number of errors that occur within the set time reaches a predetermined threshold value n. n is a natural number of 3 or more (n ≧ 3), and is predetermined.

  As shown in FIG. 7, the control device 7 includes a plurality of timers 23 for measuring time. The number of the timers 23 is a number obtained by subtracting 1 from the predetermined threshold value n, that is, n-1. Each of the plurality of timers is configured to measure time, stop measuring the time when the measured time reaches a set time, and reset the measured time to zero. The control device 7 starts one of the plurality of timers each time an error occurs, and if all of the plurality of timers are measuring the time when the error occurs, the control device 7 The apparatus 5 is configured not to restart.

  FIG. 8 is a time chart for explaining the operation of the timer when errors occur at a low frequency. In the example shown in FIG. 8, five timers 23A, 23B, 23C, 23D, and 23E are provided, and the set time is 10 minutes. Whenever an error occurs, the control device 7 (see FIG. 7) starts one of these timers 23A, 23B, 23C, 23D, and 23E according to a predetermined order. In this example, when the error E1 occurs, the timer 23A is started and time measurement is started. When the error E2 occurs, the timer 23B is started and time measurement is started. Similarly, when errors E3, E4, E5 occur, timers 23C, 23D, 23E are started in this order.

  The timers 23 </ b> A to 23 </ b> E end the time measurement when the measured time reaches the set time of 10 minutes, and reset the measured time to 0. Therefore, when the error occurrence frequency is low and the sixth error E6 has occurred, the time measurement operation of the first timer 23A has already been completed, and the timer 23A can restart the time measurement. As described above, when an error occurs at a low frequency, any one of the five timers 23A to 23E can start measuring time each time an error occurs.

  On the other hand, FIG. 9 is a time chart for explaining the operation of the timer when errors occur at a high frequency. In this example, similarly, the five timers 23A to 23E are sequentially started when the errors E1 to E5 occur. However, when the sixth error E6 occurs, the first timer 23A is still measuring time. The other timers 23B to 23E also measure time in the same manner. Thus, when errors occur frequently, all timers including the timer 23A have not finished measuring the previous time, and thus cannot start measuring time.

  As can be seen from FIG. 9, the fact that all n−1 timers 23 are measuring time when an error occurs means that the error has occurred n times within the set time, That is, it means that errors occur frequently. Therefore, in such a case, the control device 7 prevents the inverter device 5 from being broken by not restarting the inverter device 5. On the other hand, when the error occurs at a low frequency as shown in FIG. 8, the control device 7 immediately restarts the inverter device 5 and continues the operation of the pump module 1.

  In the present embodiment, a plurality of timers 23 are employed in order to determine whether or not the number of errors that have occurred within the set time has reached a predetermined threshold value. Although it is possible to determine whether or not the number of errors that have occurred within the set time has reached a predetermined threshold value using one timer, using a plurality of timers 23, errors can be determined. It is possible to quickly and reliably detect occurrence of high frequency. Hereinafter, advantages of using the plurality of timers 23 will be described with reference to FIGS. 9 and 10.

  In the example shown in FIG. 9, the threshold value of the number of occurrences of errors is set to 6. In other words, the error is allowed to occur up to 5 times within the set time (10 minutes in FIG. 9), but if the error occurs 6 times, the control device 7 does not restart the inverter device 5. FIG. 10 is a time chart illustrating a method for determining whether or not the number of errors that have occurred within a set time has reached a predetermined threshold using one timer. In the example shown in FIG. 10 as well, the threshold value for the number of occurrences of errors is set to 6.

  As shown in FIG. 10, the timer repeatedly measures the set time (10 minutes in FIG. 10), and the control device 7 counts the number of errors that have occurred within this set time. Errors E1, E2, E3, E4 occur within the first set time. Therefore, the number of errors that occurred within the first set time is 4 and is smaller than the threshold value 6. Errors E5, E6, E7, E8 occur within the next set time. Therefore, the number of errors that occurred within the next set time is also 4 and is smaller than the threshold value 6.

  However, the errors E2, E3, E4, E5, E6, and E7 have occurred within the set time of 10 minutes. This means that 6 errors have occurred within 10 minutes. If only one timer is used, the control device 7 may not be able to detect such a high frequency error occurrence.

  On the other hand, according to the present embodiment shown in FIG. 9, every time an error occurs, any one of the plurality of timers 23A to 23E starts measuring time in order. Therefore, the control device 7 can quickly and reliably detect that errors have occurred frequently.

  The embodiment described above is described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the present invention is not limited to the described embodiments, but is to be construed in the widest scope according to the technical idea defined by the claims.

DESCRIPTION OF SYMBOLS 1 Pump module 2 Motor 5 Inverter apparatus 7 Control apparatus 8 Sealed container 11 Converter part 15 Smoothing capacitor 12 Inverter part 13 Gate driver 16 Inverter control part 22 Counter 23, 23A-23E Timer

Claims (11)

A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A control device for controlling the inverter device;
The inverter device stops its operation when an error due to overvoltage or overcurrent occurs,
The control device continues the operation of the pump module by restarting the inverter device before the motor completely stops if the occurrence of the error satisfies a predetermined condition. To vacuum pump. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A control device for controlling the inverter device;
The inverter device stops its operation when an error due to overvoltage or overcurrent occurs,
The control device is configured to restart the inverter device if the occurrence of the error satisfies a predetermined condition,
The vacuum pump is characterized in that an error has occurred within a predetermined time after the power failure is restored and the supply of power is resumed. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A control device for controlling the inverter device;
The inverter device stops its operation when an error due to overvoltage or overcurrent occurs,
The control device is configured to restart the inverter device if the occurrence of the error satisfies a predetermined condition,
The vacuum pump according to claim 1, wherein the predetermined condition is that an error has occurred within a predetermined time from the time when the inverter device starts decelerating the motor in accordance with a command from the control device. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A control device for controlling the inverter device;
The inverter device stops its operation when an error due to overvoltage or overcurrent occurs,
The control device is configured to restart the inverter device if the occurrence of the error satisfies a predetermined condition,
The vacuum pump is characterized in that the predetermined condition is that an error has occurred when the inverter device rotates the motor at an idle speed lower than its rated speed.   The control device counts the number of times the error has occurred, and resets the counted number to 0 when the error has not occurred within a predetermined monitoring time. The vacuum pump according to any one of claims 1 to 4, wherein when the threshold value is reached, the inverter device is not restarted.   The inverter device includes a converter unit that converts three-phase AC power into DC power, and an inverter unit that includes a switching element that generates three-phase AC power from the DC power. The vacuum pump as described in any one of thru | or 5. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A vacuum pump operating method comprising a control device for controlling the inverter device,
If an error due to overvoltage or overcurrent occurs, stop the operation of the inverter device,
If the occurrence of the error satisfies a predetermined condition, the operation of the pump module is continued by restarting the inverter device before the motor completely stops. Method. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A vacuum pump operating method comprising a control device for controlling the inverter device,
If an error due to overvoltage or overcurrent occurs, stop the operation of the inverter device,
If the occurrence of the error satisfies a predetermined condition, to restart the pre-Symbol inverter device,
The method of operating a vacuum pump, wherein the predetermined condition is that an error has occurred within a predetermined time after the power failure is restored and the supply of power is resumed. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A vacuum pump operating method comprising a control device for controlling the inverter device,
If an error due to overvoltage or overcurrent occurs, stop the operation of the inverter device,
If the occurrence of the error satisfies a predetermined condition, restart the inverter device before the motor completely stops,
The vacuum pump operating method according to claim 1, wherein the predetermined condition is that an error has occurred within a predetermined time from the time when the inverter device starts to decelerate the motor in accordance with a command from the control device. A pump module for exhausting the gas;
A motor for driving the pump module;
An inverter device for supplying AC power of variable frequency to the motor;
A vacuum pump operating method comprising a control device for controlling the inverter device,
If an error due to overvoltage or overcurrent occurs, stop the operation of the inverter device,
If the occurrence of the error satisfies a predetermined condition, restart the inverter device before the motor completely stops,
The predetermined condition is that an error has occurred when the inverter device is rotating the motor at an idle speed lower than its rated speed. Count the number of times the error has occurred,
When the error does not occur within a predetermined monitoring time, the counted number is reset to 0,
The method of operating a vacuum pump according to any one of claims 7 to 10, wherein the inverter device is not restarted when the counted number of times reaches a predetermined threshold value.

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