JP2023097573A - Servo amplifier and open-phase determination method - Google Patents

Abstract

To surely avoid a malfunction of a servo amplifier even when fluctuations of an input power source exist.SOLUTION: A master open-phase waveform analysis unit 113 analyzes whether or not power from an input power source 200 is deviated from a first allowable value based on a sampled value, and a master open-phase waveform determination unit 114 samples power and determines a master open-phase waveform when analysis results of the master open-phase waveform analysis unit 113 is normal. A polling open-phase waveform analysis unit 115 compares a polling open-phase waveform obtained from a value sampled after determination of the master open-phase waveform with the master open-phase waveform, and a main control unit 110 notifies an error each of when the master open-phase waveform determination unit 114 is determined to be abnormal and when a polling open-phase waveform determination unit 116 is abnormal.SELECTED DRAWING: Figure 1

Description

The present invention relates to a servo amplifier and an open-phase determination method suitable for avoiding malfunction of a servo amplifier due to fluctuations in input power.

When a servo system motor is attached to a target device such as a robot or a machine tool, it is necessary to adjust the gain of the servo amplifier according to the load inertia. Such servo amplifier gain adjustment is performed by manually or automatically setting parameters.

By the way, if the power from the input power supply supplied to the servo amplifier fluctuates, not only will gain adjustment have to be redone, but the servo amplifier may malfunction.

A control gain setting method for a servo amplifier as disclosed in Patent Document 1 is known as a method for coping with such power fluctuations. In this control gain setting method, in a servo motor driven by a servo amplifier, a step-like reactive current component is supplied to a current loop, a step response obtained from the current loop is obtained, and the voltage input to the servo amplifier is calculated based on the step response. is measured, and the control gain is set by using a preset control parameter corresponding to the measured power supply voltage.

JP-A-08-205569

However, in the control gain setting method of Patent Document 1, it is necessary to supply a step-like reactive current component to the current loop while the servo amplifier is in operation, and measure the voltage input to the servo amplifier based on the step response. Therefore, it cannot be confirmed whether the power to the servo amplifier is in a state that does not cause malfunction of the servo amplifier before the servo amplifier starts operating.

Further, for example, when power is supplied to a servo amplifier via a transformer, the power supplied to the servo amplifier may fluctuate if there is variation in the transformation accuracy of the transformer.

In this case, it is considered that the control gain can be appropriately set by using a preset control parameter corresponding to the measured power supply voltage as in the control gain setting method of Patent Document 1. However, unless control parameters corresponding to variations in transformation accuracy of the transformer are set in advance, the control gain cannot be appropriately set, and the control parameters must be set again.

In addition, if the control parameters are forgotten to be set again or are set incorrectly, the servo amplifier may malfunction.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a servo amplifier and an open phase determination method that can solve the above problems.

The servo amplifier of the present invention analyzes whether or not the power from the input power supply deviates from the first allowable value based on the values sampled under constant conditions, and outputs an error if it deviates. and a first open phase including a first characteristic obtained from the sampled value when the power is sampled under the constant condition and the analysis result by the first analysis unit is normal. A second open-phase waveform determination unit for determining a waveform, the first characteristic, and a second open-phase waveform obtained from values sampled under the constant condition after determination of the first open-phase waveform. a second analysis unit that compares the characteristics and analyzes whether the second characteristic deviates from the second allowable value with respect to the first characteristic, and outputs an error if deviated; , after determining the first open-phase waveform, the power is sampled under a certain condition, and if the analysis result by the second analysis unit does not deviate from the second allowable value, the open-phase is determined to be normal. When the waveform determination unit and the open phase waveform determination unit determine that there is an abnormality based on the error output from the first analysis unit, and the error output by the open phase waveform determination unit from the second analysis unit and a main control unit that notifies an error in each of the cases where it is determined that there is an abnormality based on the above.
Further, the constant condition includes a constant threshold value and a constant sampling period, the first characteristic includes a first frequency and a first duty, the second characteristic includes a second frequency and a second Duty, the first tolerance includes a manually or automatically set third frequency and a third Duty, the second tolerance is manually or automatically set Including a fourth frequency and a fourth duty, the open phase waveform determination unit binarizes the power using the constant threshold value and the constant sampling period, and the first analysis unit is the Based on the time difference between the timing at which the sampled value switches from LOW to HIGH and the timing at which it switches from HIGH to LOW, the first frequency and the first duty are obtained, and any one of the first frequency and the first duty Or analyze whether it is not shifted from any or all of the third frequency and the third Duty, and the open phase waveform determination unit uses the constant threshold value and the constant sampling period and the second analysis unit converts the second frequency and the second It is characterized by analyzing whether any or all of the second frequency and the second duty are deviated from any or all of the fourth frequency and the fourth duty do.
Further, the third frequency and the third duty have values within a certain range, and the fourth frequency and the fourth duty have values within a certain range. .
In the open phase determination method of the present invention, the first analysis unit analyzes whether or not the power from the input power supply deviates from the first allowable value based on the value sampled under constant conditions, a step of outputting an error if it is, and sampling the power under the constant condition by the open phase waveform determination unit, and obtaining from the sampled value when the analysis result by the first analysis unit is normal. a step of determining a first open-phase waveform including a first characteristic that is obtained; and a second analysis unit sampled under the constant condition after determining the first characteristic and the first open-phase waveform Compare with the second characteristic of the second open phase waveform obtained from the value obtained, and analyze whether the second characteristic deviates from the second allowable value with respect to the first characteristic, A step of outputting an error if there is a deviation, and after the first open-phase waveform is determined by the open-phase waveform determination unit, the power is sampled under a certain condition, and the analysis result by the second analysis unit is A step of determining that it is normal if it does not deviate from the second allowable value; and when the open-phase waveform determination unit determines that there is an abnormality based on the error output from the second analysis unit, the error is notified.
Further, the constant condition includes a constant threshold value and a constant sampling period, the first characteristic includes a first frequency and a first duty, the second characteristic includes a second frequency and a second Duty, the first tolerance includes a manually or automatically set third frequency and a third Duty, the second tolerance is manually or automatically set A step of binarizing the power using the constant threshold value and the constant sampling period by the open phase waveform determination unit, including a fourth frequency and a fourth duty, and the first analysis unit obtains the first frequency and the first duty based on the time between the timing at which the sampled value switches from LOW to HIGH and the timing at which the sampled value switches from HIGH to LOW; A step of analyzing whether any or all of the 1 Duty does not deviate from any or all of the third frequency and the third Duty, and by the open phase waveform determination unit, the constant threshold value and the a step of binarizing the power using a constant sampling period; Based on time, the second frequency and the second duty are obtained, and any or all of the second frequency and the second duty are from any or all of the fourth frequency and the fourth duty and a step of analyzing whether there is any deviation.
Further, the third frequency and the third duty have values within a certain range, and the fourth frequency and the fourth duty have values within a certain range. .
In the servo amplifier and the open phase determination method of the present invention, the open phase waveform determination unit that samples the power under a constant condition determines the first open phase waveform from the analysis result of the first analysis unit based on the first allowable value to decide. Further, the phase waveform determination unit that samples the missing power under a certain condition determines the first characteristic of the first missing phase waveform and the second characteristic of the first missing phase waveform based on the second allowable value after determining the first missing phase waveform. Normality or abnormality of the second open-phase waveform is determined from a second analysis unit that compares the second characteristic of the open-phase waveform. Then, the main control unit determines that the open phase waveform determination unit is abnormal based on the error output from the first analysis unit, and the open phase waveform determination unit based on the error output from the second analysis unit An error is reported in each of the cases where it is determined that there is an abnormality.

According to the servo amplifier and the open-phase determination method of the present invention, the first open-phase waveform, which serves as an index of the stability of the operation of the servo amplifier, can be determined first. You can check whether it is in a state where it does not wake up.
A second open-phase waveform is determined based on a first tolerance set manually or automatically and is compared with the first open-phase waveform based on a second tolerance. is determined to be normal or abnormal, it is possible to easily set the parameters of the servo amplifier.
In addition, the normality or abnormality of the first open-phase waveform is determined, and the normality or abnormality of the second open-phase waveform is determined. Malfunction of the servo amplifier can be reliably avoided.

1 is a diagram for explaining an embodiment of a servo amplifier of the present invention; FIG. It is for explaining an example of waveform analysis for a single-phase input voltage by the servo amplifier of FIG. 1, FIG. 2(a) is a diagram showing the input voltage before rectification, and FIG. 2(c) is a diagram showing a sampling waveform for the input voltage of FIG. 2(b). It is for explaining an example of waveform analysis for a three-phase input voltage by the servo amplifier of FIG. 1, FIG. Fig. 3(c) is a diagram showing a sampling waveform of the L2 phase; Fig. 3(d) is a diagram showing a sampling waveform of the L3 phase; FIG. 4 is a diagram showing sampling waveforms obtained by synthesizing L1 to L3 phases; An example of a specific event of power fluctuation from the input power supply in FIG. 1 will be described. FIG. 4A is a diagram showing a normal waveform, and FIG. It is a figure which shows an example, and FIG.4(c) is a figure which shows an example of the waveform which amplitude shifted. 2 is a flowchart for explaining an example of master open-phase waveform determination processing by the servo amplifier of FIG. 1; 4 is a flowchart for explaining an example of master open-phase waveform analysis processing by the servo amplifier of FIG. 1; 2 is a flowchart for explaining an example of polling open-phase waveform determination processing by the servo amplifier of FIG. 1; 2 is a flowchart for explaining an example of polling open-phase waveform analysis processing by the servo amplifier of FIG. 1;

An embodiment of the servo amplifier of the present invention will be described below with reference to FIGS. 1 to 8. FIG. In the following description, the master open-phase waveform is a waveform determined by a master open-phase waveform determination unit 114 described later, for example, before the start of operation of the servo amplifier 100 described later. It is an index. By determining this master open-phase waveform, it is possible to confirm whether or not the input power supply 200 is in a state that does not cause malfunction of the servo amplifier 100 before the servo amplifier 100 starts operating. Further, the polling open phase waveform refers to the master open phase waveform determined by the polling open phase waveform determination unit 116 described later after the start of operation of the servo amplifier 100, which is after the master open phase waveform is determined by the master open phase waveform determination unit 114. It is a waveform for use in comparison with .

Also, in the following description,
(first open-phase waveform) ... master open-phase waveform (second open-phase waveform) ... polling open-phase waveform (first characteristic) ... frequency of master open-phase waveform (first frequency ) and pulse width (first duty) (single-phase and three-phase common).
(Second characteristic) . . . includes frequency (second frequency) and pulse width (second duty) of polling open-phase waveform (single-phase and three-phase common).
(First permissible value) . ).
(Second allowable value) . . . including the frequency (fourth frequency) and duty (fourth duty) set manually or automatically after the servo amplifier 100 starts operating (single-phase and three-phase common) .
It has become.

First, as shown in FIG. 1, the servo amplifier 100 has a main control section 110 . The main control unit 110 includes a single-phase/three-phase setting unit 112, a master open-phase waveform analysis unit 113, a master open-phase waveform determination unit 114, a polling open-phase waveform analysis unit 115, and a A polling open phase waveform determination unit 116 and a monitor control unit 117 are connected. The servo amplifier 100 also has terminals L 1 , L 2 , and L 3 connected to an input power source 200 (for example, 200 V), and terminals U, V, and W connected to the motor 300 . The input power supply 200 may be a commercial power supply, or may be a transformer interposed between the commercial power supply and the servo amplifier 100 to transform power from the commercial power supply.

The main control unit 110 controls cooperative operations of each unit. Further, the main control unit 110 determines that the master open phase waveform determination unit 114 is abnormal based on the error output from the master open phase waveform analysis unit 113, and the polling open phase waveform determination unit 116 analyzes the polling open phase waveform. The monitor control unit 117 is instructed to notify the error in each of the cases where it is determined that there is an abnormality based on the error output from the unit 115 .

The single-phase/three-phase setting unit 112 detects the input voltage obtained via any one of the terminals L1, L2, and L3 or all of the terminals L1 to L3, and determines whether the input voltage is single-phase or three-phase. set whether Note that the single-phase/three-phase setting unit 112 may detect the input current instead of the input voltage and set single-phase or three-phase.

Before the start of operation of the servo amplifier 100, the master open-phase waveform analysis unit 113 obtains a value sampled under certain conditions by the master open-phase waveform determination unit 114, which will be described later, from the AC voltage, which is the power from the input power supply 200. Based on this, it is analyzed whether or not there is a deviation from the first allowable value, and if there is a deviation, an error is output. In the analysis by the master open phase waveform analysis unit 113, the master A frequency (first frequency) and a pulse width (first duty) of an open-phase waveform are obtained. Then, the master open-phase waveform analysis unit 113 determines whether one or all of the obtained first frequency and first duty is a manually or automatically set frequency (third frequency ) and Duty (third duty), or whether there is any deviation from all or not.

When a transformer (not shown) is interposed between the input power supply 200 and the AC voltage from the transformer, similarly, the value sampled under a certain condition by the master open-phase waveform determination unit 114 is used as the basis. Then, it analyzes whether it deviates from the first allowable value, and outputs an error if it deviates.

Here, the constant conditions include a constant threshold value (eg, 100 V) and a constant sampling period (eg, 400 usec). The fixed threshold value and the fixed sampling period can be changed as appropriate. Also, the first allowable value includes the frequency (third frequency) and duty (third duty) manually or automatically set before the servo amplifier 100 starts operating. Although the sampled values are based on the AC voltage here, they may be based on the AC current instead of the AC voltage. Also, the constant threshold value (for example, 100V) is not limited to 100V and may be set arbitrarily. Also, the sampling period (for example, 400 usec) is not limited to 400 usec, and may be based on alternating current.

Also, the first allowable value includes a frequency (third frequency) and a duty (third duty) manually or automatically set before the servo amplifier 100 starts operating. Here, the frequency (third frequency) represents the allowable deviation amount with respect to the frequency (first frequency) of the master open-phase waveform in percentage. Duty (third duty) is a percentage of the allowable shift amount with respect to the pulse width (first duty) of the master open-phase waveform. That is, the first allowable value means an amount of deviation (for example, 10%) that the master open-phase waveform determining unit 114 (to be described later) allows for a constant sampled pulse waveform.

The first allowable value may be a value with a certain range (for example, 10 to 20%), or may be a value without a certain range. If the value does not have a fixed range, it may be the maximum value (eg 20%), the minimum value (eg 10%) or the average value (eg 15%) of the allowable values of the frequency and duty.

In addition, in the analysis by the master open-phase waveform analysis unit 113, fluctuations in power from the input power supply 200 can be caused by natural disasters such as lightning strikes and typhoons. On the other hand, fluctuations in power from a transformer (not shown) may be due to variations in the transformer's transformation precision. As a specific example of these power fluctuations, there is a frequency deviation as shown in FIG. 4(b) with respect to the normal waveform shown in FIG. Amplitude deviation is considered.

Before the start of operation of the servo amplifier 100, the master open-phase waveform determining unit 114 completely removes the AC voltage from the input power supply 200 as shown in FIG. 2B showing a single phase and FIG. Wave rectification is performed, sampling is performed under the constant conditions described above, binarization is performed, and pulse waveforms such as those shown in FIGS. 2(c) and 3(e) are output. Note that the voltage of the pulse waveform is, for example, 5V. In addition, a to e shown in FIG. 2(c) show change points corresponding to the rise and fall of the pulse obtained by sampling of the master open phase waveform determination unit 114, the details of which will be described later. .

Further, when the analysis result by the master open phase waveform analysis unit 113 is normal, the master open phase waveform determination unit 114 determines the master open phase waveform including the first characteristic obtained from the sampled values. The first characteristic includes the frequency (first frequency) and pulse width (first duty) of the master open-phase waveform obtained from the values sampled by the master open-phase waveform determination unit 114 .

Here, when the AC voltage is single-phase as shown in FIG. 2(a), the master open-phase waveform determining unit 114 performs full-wave rectification of the AC voltage as shown in FIG. 2(b). Further, the master open-phase waveform determining unit 114 performs sampling under certain conditions including the above-mentioned certain threshold value (for example, 100 V) and a certain sampling period (for example, 400 usec), as shown in FIG. Get the pulse waveform.

Further, when the AC voltage is three-phase, the master open-phase waveform determining unit 114 performs full-wave rectification of the AC voltage as shown in FIG. 3(a). Moreover, the master open-phase waveform determining unit 114 obtains the pulse waveform shown in FIG. The pulse waveforms include the L1-phase pulse waveform shown in FIG. 3(b), the L2-phase pulse waveform shown in FIG. 3(c), and the L3-phase pulse waveform shown in FIG. 3(d). Note that the master open-phase waveform determining unit 114 performs full-wave rectification of the AC voltage, but may also perform full-wave rectification of the AC current. Further, the master open-phase waveform determination unit 114 performs full-wave rectification of the AC voltage, but may also perform half-wave rectification of the AC voltage.

After the master open-phase waveform (first open-phase waveform) is determined (after the servo amplifier 100 starts operating), the polling open-phase waveform analysis unit 115 determines the frequency of the master open-phase waveform (first frequency) and pulse width (first duty), and the above constant sampling period (for example, 400 usec), based on certain conditions including the above-mentioned constant sampling period Sampling by the polling open phase waveform determination unit 116 described later The second characteristics including the frequency (second frequency) and pulse width (second duty) of the poling open-phase waveform obtained from the obtained values are compared.

In addition, in the analysis by the polling open phase waveform analysis unit 115, based on the time difference between the timing at which the value sampled by the polling open phase waveform determination unit 116 (to be described later) switches from LOW to HIGH and the timing at which it switches from HIGH to LOW, polling The frequency (second frequency) and pulse width (second duty) of the open-phase waveform are obtained. Then, the polling open-phase waveform analysis unit 115 determines that one or all of the obtained second frequency and second duty is a frequency (fourth frequency) that is manually or automatically set after the servo amplifier 100 starts operating. and duty (fourth duty).

In addition, the polling open phase waveform analysis unit 115 analyzes whether the amount of deviation of the second characteristic with respect to the first characteristic is within the second allowable value, and if it is not within the second allowable value Output an error. If the comparison result of the frequency (second frequency) of the polling open-phase waveform with respect to the frequency (first frequency) of the master open-phase waveform is not within the second allowable value, the error output is the master open-phase waveform Either or both of the cases where the comparison result of the pulse width (second duty) of the polling open-phase waveform with respect to the pulse width (first duty) is not within the second allowable value.

The second allowable value includes the frequency (third frequency) and duty (third duty) manually or automatically set after the servo amplifier 100 starts operating. Here, the frequency (third frequency) is, similarly to the above, the permissible amount of deviation with respect to the frequency (first frequency) of the master open-phase waveform expressed in percentage. Duty (third duty) is a percentage of the allowable shift amount with respect to the pulse width (first duty) of the master open-phase waveform.

The frequency (third frequency) and duty (third duty) may be values with a certain range or values without a certain range, as described above. If the value does not have a fixed range, it may be either the maximum value, minimum value, or average value of frequency and duty.

The polling open-phase waveform determination unit 116 samples and binarizes the AC voltage under the above-described constant conditions during the start of operation of the servo amplifier 100 after the master open-phase waveform is determined, If the analysis result by the polling open phase waveform analysis unit 115 does not deviate from the second allowable value, the waveform is determined to be normal.

A monitor 120 is connected to the monitor control unit 117 . When the monitor control unit 117 receives an error notification instruction from the main control unit 110, the monitor control unit 117 notifies the monitor 120 of the error. The content of the notification may be, for example, an indication that the servo amplifier 100 may malfunction due to voltage fluctuation. In any case, the content of the notification should be able to inform the user that there is a possibility that the servo amplifier 100 may malfunction. In addition, when an error is notified, the user may be informed of the error by a warning sound generated by a buzzer.

Next, with reference to FIG. 5, the master open-phase waveform determination process will be described. In the following explanation, the judgment based on the binarized value is based on negative logic for convenience of explanation.

(Step S101)
When the power supply of the servo amplifier 100 is turned on, the master open-phase waveform determination unit 114, according to the instruction of the main control unit 110, N set in a memory (not shown) (a value indicating a single phase change by sampling), and M (values indicating changes in three phases by sampling) are initialized.

(Step S102)
The master open-phase waveform determining unit 114 full-wave rectifies each phase voltage and sets the binarized value in a memory (not shown).
In this case, if the AC voltage is single-phase as shown in FIG. , sampling is performed at a constant sampling period (eg, 400 usec) based on the aforementioned constant threshold value (eg, 100 V), and the binarized value is set in a memory (not shown).
In the case of three phases, the master open-phase waveform determination unit 114 performs full-wave rectification of the AC voltage from the input power supply 200 as shown in FIG. Then, sampling is performed at a constant sampling period (for example, 400 usec), and the binarized value is set in a memory (not shown).

(Step S103)
The master open-phase waveform determination unit 114 determines whether there is a change in voltage level between the previous time and this time.
In this case, the master open phase waveform determination unit 114, for example, if the sampled value is 0 and the next sampled value is 1, it determines that there is a change in the voltage level (step S103: Yes), and proceeds to step S104. Transition.
On the other hand, if the sampled value is 0 and the next sampled value is 0, for example, the master open phase waveform determination unit 114 determines that the voltage level does not change (step S103: No), and step S110. transition to
Note that if the sampled value is 1 and the next sampled value is 1, the master open phase waveform determination unit 114 similarly determines that the voltage level has not changed.

(Step S104)
The master open-phase waveform determination unit 114 records 1 in N, which indicates a single-phase change, in the arrangement of a ring buffer (not shown) (N=1).

(Step S105)
The master open phase waveform determining unit 114 determines whether N≧5.
In this case, when N is less than 5, the master open-phase waveform determining unit 114 determines that N≧5 is not true (step S105: No), and proceeds to step S102.
On the other hand, when N is 5 or more, the master open-phase waveform determining unit 114 determines that N≧5 (step S105: Yes), and proceeds to step S106.
Here, when N is 5, as shown in FIG. 2(c), five a to e (variation point). Note that the master open-phase waveform determining unit 114 determines whether N is 5 or more, but may also determine if N exceeds 5 or more.

(Step S106)
The master open-phase waveform analysis unit 113 analyzes the master open-phase waveform.
The details of the analysis of the master open-phase waveform by the master open-phase waveform analysis unit 113 will be described later with reference to FIG.

(Step S107)
The master open-phase waveform determination unit 114 determines whether the analysis result of the master open-phase waveform is normal.
In this case, the master open phase waveform determination unit 114 analyzes that both the frequency and the duty obtained from the values sampled under certain conditions by the master open phase waveform analysis unit 113 described later are within the allowable value, the master open phase waveform is normal (step S107: Yes), and the process proceeds to step S108.
On the other hand, the master open phase waveform determination unit 114 analyzes that one or all of the frequency and duty obtained from the values sampled under certain conditions by the master open phase waveform analysis unit 113, which will be described later, is not within the allowable value. If an error is output, it is determined that the analysis result of the master open phase waveform is not normal (step S107: No), and the process proceeds to step S109.

(Step S108)
The master open-phase waveform determining unit 114 determines a single-phase master open-phase waveform.
In this case, the master open-phase waveform determination unit 114 determines a waveform having a frequency and duty obtained from values sampled under certain conditions as a single-phase master open-phase waveform, and the master open-phase waveform analysis unit 113 described later The determined frequency (first frequency) and pulse width (first duty) of the master open-phase waveform are stored in a memory (not shown) as first characteristics.

(Step S109)
In step S107, the main control unit 110 outputs when the master open phase waveform determination unit 114 analyzes that the master open phase waveform analysis unit 113 described later does not have one or all of the frequency and duty within the allowable value When it is determined that the analysis result of the master open-phase waveform is not normal based on the error, the monitor 120 is made to report the error via the monitor control unit 117 .

(Step S110)
The master open phase waveform determination unit 114 determines whether the voltage level is LOW.
In this case, as shown in FIG. 3E, the master open phase waveform determination unit 114 determines that the voltage level is LOW by negative logic when all the sampled values are 1 (step S110: Yes ), the process proceeds to step S111.
On the other hand, if the sampled value is 0 in step S103 and the next sampled value is 0, the master open phase waveform determining unit 114 determines that the voltage level is HIGH by negative logic (step S110 : No), the process proceeds to step S112.

(Step S111)
The master open phase waveform determination unit 114 counts LOW.

(Step S112)
The master open phase waveform determination unit 114 counts HIGH.

(Step S113)
The master open-phase waveform determining unit 114 determines whether M, which is the total number of LOW count values and HIGH count values, is greater than a specified number of times (eg, 200). Note that the specified number of times is not limited to 200, and can be changed arbitrarily.
In this case, when the master open phase waveform determination unit 114 determines that M, which is the total number of the LOW count value and the HIGH count value, is larger than the specified number of times (step S113: Yes), the process proceeds to step S114.
On the other hand, when the master open-phase waveform determining unit 114 determines that M, which is the total number of the LOW count value and the HIGH count value, is not larger than the specified number of times (step S113: No), the process proceeds to step S102.

(Step S114)
The master open-phase waveform determination unit 114 determines whether the LOW count value is greater than the HIGH count value.
In this case, when the master open-phase waveform determination unit 114 determines that the LOW count value is greater than the HIGH count value (step S114: Yes), the process proceeds to step S115.
On the other hand, when the master open-phase waveform determination unit 114 determines that the LOW count value is not greater than the HIGH count value (step S114: No), the process proceeds to step S116.
If the LOW count value is not greater than the HIGH count value, it means that an open phase has occurred.

(Step S115)
The master open-phase waveform determining unit 114 determines a three-phase master open-phase waveform.
In this case, the master open-phase waveform determination unit 114 determines a waveform having a frequency and duty obtained from values sampled under certain conditions as a three-phase master open-phase waveform, and the master open-phase waveform analysis unit 113 described later The determined frequency (first frequency) and pulse width (first duty) of the master open-phase waveform are stored in a memory (not shown) as first characteristics.

(Step S116)
When the master open-phase waveform determination unit 114 determines that the LOW count value is not larger than the HIGH count value in step S114, the main control unit 110 causes the monitor 120 to report an error via the monitor control unit 117.

Next, the master open-phase waveform analysis process will be described with reference to FIG. It is assumed that both the frequency and duty tolerance values, which are the first tolerance values described below, have values within a certain range.

(Step S201)
The master open phase waveform analysis unit 113 obtains the frequency based on the time difference between the change points.
Here, for example, in the pulse waveform shown in FIG. 2(c), it is assumed that four change points a to d are obtained per cycle. In this case, the frequency of the master open-phase waveform can be obtained by obtaining the time difference between a and b, for example, and then obtaining the reciprocal of the obtained time difference.

(Step S202)
The master open phase waveform analysis unit 113 sets the allowable values of the frequency (third frequency) and Duty (third duty), which are the first allowable values, in a memory (not shown).
In this case, the master open phase waveform analysis unit 113 may accept and set the frequency and duty tolerance values set by the user, or automatically acquire the preset frequency and duty tolerance values. May be set.
Note that the allowable value here is the allowable deviation amount between the frequency and the duty obtained by sampling by the master open-phase waveform determining unit 114, which is expressed in percentage, as described above.

(Step S203)
The master open phase waveform analysis unit 113 determines whether the frequency is within the allowable range.
In this case, when the master open phase waveform analysis unit 113 determines that the frequency obtained in step S201 is within the allowable range of frequencies set in step S202 (step S203: Yes), the process proceeds to step S204. .
On the other hand, when the master open phase waveform analysis unit 113 determines that the frequency obtained in step S201 is not within the allowable frequency range set in step S202 (step S203: No), the process proceeds to step S207. .
Note that the master open phase waveform analysis unit 113 can determine whether the obtained frequency is within the allowable value by confirming whether the frequency deviation amount obtained in step S201 is within the percentage of the allowable value.

(Step S204)
The master open phase waveform analysis unit 113 obtains the duty.
In this case, the master open phase waveform analysis unit 113, in the same manner as described above, for example, in the pulse waveform shown in FIG. .

(Step S205)
The master open phase waveform analysis unit 113 determines whether the obtained Duty is within the allowable value.
In this case, when the master open phase waveform analysis unit 113 determines that the Duty obtained in step S204 is within the allowable value of the duty within a certain range set in step S202 (step S205: Yes), the process proceeds to step S206 .
On the other hand, when the master open phase waveform analysis unit 113 determines that the Duty obtained in step S204 is not within the allowable value of the duty within the certain range set in step S202 (step S205: No), the process proceeds to step S207 .
Note that the allowable value here is a manually or automatically set duty (third duty). Duty (3rd Duty) is, similarly to the above, the allowable deviation amount with respect to the pulse width (first Duty) of the master open phase waveform expressed in percentage, and the deviation amount of Duty obtained in step S204 is allowed By checking whether it is within the percentage of the value, it can be determined whether the obtained duty is within the allowable value.

(Step S206)
The master open phase waveform analysis unit 113 determines the frequency (first frequency) and the duty (first duty) that are the first characteristics.

(Step S207)
The master open phase waveform analysis unit 113 outputs an error.

Next, referring to FIG. 7, the polling open-phase waveform determination process will be described. In the following explanation, the judgment based on the binarized value is based on negative logic as in the above.

(Step S301)
The polling open-phase waveform determination unit 116 performs full-wave rectification on each phase voltage and sets the binarized value in a memory (not shown).
In this case, when the AC voltage is single-phase as shown in FIG. 2(a), the polling open-phase waveform determining unit 116 performs full-wave rectification of the AC voltage from the input power supply 200 as shown in FIG. 2(b). , sampling is performed at a constant sampling period (eg, 400 usec) based on the aforementioned constant threshold value (eg, 100 V), and the binarized value is set in a memory (not shown).
In the case of three-phase, the polling open-phase waveform determination unit 116 performs full-wave rectification of the AC voltage from the input power supply 200 as shown in FIG. Then, sampling is performed at a constant sampling period (for example, 400 usec), and the binarized value is set in a memory (not shown).

(Step S302)
The polling open-phase waveform determination unit 116 determines whether or not there is a change in voltage level between the previous time and this time.
In this case, if the sampled value is 0 and the next sampled value is 1, the polling open phase waveform determination unit 116 determines that there is a change in the voltage level (step S302: Yes). The process proceeds to step S303.
On the other hand, if the sampled value is 0 and the next sampled value is 0, the polling open phase waveform determination unit 116 determines that the voltage level does not change (step S302: No), and proceeds to step S308. Transition.

(Step S303)
The polling open-phase waveform determining unit 116 records 1 in N indicating a single-phase change (N=1) in the arrangement of a ring buffer (not shown).

(Step S304)
The polling open phase waveform determination unit 116 determines whether N≧5.
In this case, when N is less than 5, the polling open-phase waveform determination unit 116 determines that N≧5 is not true (step S304: No), and proceeds to step S301.
On the other hand, when N is 5 or more, the polling open-phase waveform determining unit 116 determines that N≧5 (step S304: Yes), and proceeds to step S305.
Here, N being 5 corresponds to five points a to e (change points) indicating the rise and fall of the pulse obtained by sampling of the polling open phase waveform determination unit 116, for example, as described above.

(Step S305)
The polling open-phase waveform analysis unit 115 analyzes the polling open-phase waveform.
In the analysis of the polling open-phase waveform by the polling open-phase waveform analysis unit 115, when either or all of the frequency and duty are not within the allowable value, an error is output. explain.

(Step S306)
The polling open-phase waveform determination unit 116 determines whether the analysis result of the polling open-phase waveform is normal.
In this case, when the polling open-phase waveform analysis unit 115, which will be described later, analyzes that both the frequency and the duty are within the allowable values, the polling open-phase waveform determination unit 116 determines that the analysis result of the polling open-phase waveform is normal. (Step S306: Yes), the process proceeds to step S301.
On the other hand, when the polling open phase waveform analysis unit 115 analyzes that one or all of the frequency and duty are not within the allowable value, the polling open phase waveform determination unit 116 determines that the analysis result of the polling open phase waveform is normal. It is determined that there is no (step S306: No), and the process proceeds to step S307.

(Step S307)
In step S406, the main control unit 110 outputs when the polling open-phase waveform determination unit 116 analyzes that one or all of the frequency and duty are not within the allowable value by the polling open-phase waveform analysis unit 115 described later. If it is determined that the analysis result of the master open phase waveform is not normal based on the error, the monitor 120 is caused to report the error via the monitor control unit 117 .

(Step S308)
The polling open phase waveform determination unit 116 determines whether the voltage level is LOW.
In this case, as shown in FIG. 3E, the polling open-phase waveform determination unit 116 determines that the voltage level is LOW by negative logic when all the sampled values are 1 (step S308: Yes ), and the process proceeds to step S309.
On the other hand, if the sampled value is 0 in step S302 and the next sampled value is 0, the polling open phase waveform determination unit 116 determines that the voltage level is HIGH by negative logic (step S308). : No), the process proceeds to step S310.

(Step S309)
The polling open phase waveform determination unit 116 counts LOW.

(Step S310)
The polling open phase waveform determination unit 116 counts HIGH.

(Step S311)
The polling open-phase waveform determining unit 116 determines whether M, which is the total number of the LOW count value and the HIGH count value, is greater than a specified number of times (eg, 200).
In this case, when the polling open phase waveform determination unit 116 determines that M, which is the total number of the LOW count value and the HIGH count value, is greater than the specified number of times (step S311: Yes), the process proceeds to step S312.
On the other hand, when the polling open phase waveform determination unit 116 determines that M, which is the total number of the LOW count value and the HIGH count value, is not greater than the specified number of times (step S311: No), the process proceeds to step S301.

(Step S312)
The polling open phase waveform determination unit 116 determines whether the LOW count value is greater than the HIGH count value.
In this case, when the polling open phase waveform determining unit 116 determines that the LOW count value is larger than the HIGH count value (step S312: Yes), the process proceeds to step S313.
On the other hand, when the polling open phase waveform determining unit 116 determines that the LOW count value is not larger than the HIGH count value (step S312: No), the process proceeds to step S307.

(Step S313)
The polling open-phase waveform determination unit 116 determines whether the master open-phase waveform is three-phase.
In this case, when the input voltage set by the single-phase/three-phase setting unit 112 is three-phase, the polling open-phase waveform determination unit 116 determines that the master open-phase waveform is three-phase (step S313: Yes). , the process proceeds to step S301.
On the other hand, when the input voltage set by the single-phase/three-phase setting unit 112 is single-phase, the polling open-phase waveform determining unit 116 determines that the master open-phase waveform is not three-phase (step S313: No). , the process proceeds to step S307.

Next, referring to FIG. 8, polling open phase waveform analysis processing will be described. Note that the frequency and duty tolerance values, which are the second tolerance values described below, both have values within a certain range, as in the case described above.

(Step S401)
The polling open-phase waveform analysis unit 115 obtains the frequency based on the time difference between the changing points.
Here, in the same manner as described above, for example, in the pulse waveform shown in FIG. 2(c), four change points a to d are obtained per cycle. In this case, the frequency of the poling open-phase waveform can be obtained in the same manner as described above by obtaining the time difference between a and b, for example, and obtaining the reciprocal of the obtained time difference.

(Step S402)
The polling open phase waveform analysis unit 115 sets the allowable values of the frequency (fourth frequency) and duty (fourth duty), which are the second allowable values, in a memory (not shown).
In this case, the polling open phase waveform analysis unit 115 may accept and set the allowable values of the frequency and duty set by the user, or automatically accept and set the allowable values of the preset frequency and duty. You may

(Step S403)
The polling open phase waveform analysis unit 115 determines whether the frequency is within the allowable range.
In this case, when the polling open phase waveform analysis unit 115 determines that the frequency obtained in step S401 is within the allowable range of frequencies set in step S402 (step S403: Yes), the process proceeds to step S404. .
On the other hand, when the polling open phase waveform analysis unit 115 determines that the frequency obtained in step S401 is not within the allowable range of frequencies set in step S402 (step S403: No), the process proceeds to step S407. .
The polling open phase waveform analysis unit 115 can determine whether the frequency obtained in step S401 is within the allowable value by confirming whether the frequency deviation amount obtained in step S401 is within the allowable percentage.

(Step S404)
The polling open phase waveform analysis unit 115 obtains Duty.
In this case, the polling open phase waveform analysis unit 115 can obtain Duty, which is the pulse width, by obtaining, for example, the time difference between a and b in the pulse waveform shown in FIG. .

(Step S405)
The polling open phase waveform analysis unit 115 determines whether the obtained Duty is within the allowable value.
In this case, when the polling open phase waveform analysis unit 115 determines that the Duty obtained in step S404 is within the allowable value of the duty within the certain range set in step S402 (step S405: Yes), the process proceeds to step S406. .
On the other hand, when the polling open phase waveform analysis unit 115 determines that the Duty obtained in step S404 is not within the allowable value of the duty within the certain range set in step S402 (step S405: No), the process proceeds to step S407. .
Note that the polling open-phase waveform analysis unit 115 can determine whether the obtained Duty is within the allowable value by confirming whether the deviation amount of the Duty obtained in step S404 is within the percentage of the allowable value.

(Step S406)
The polling open-phase waveform analysis unit 115 outputs an analysis result indicating that the waveform is normal.

(Step S407)
The polling open phase waveform analysis unit 115 outputs an error.

As described above, in the present embodiment, the master open phase waveform analysis unit 113 (first analysis unit) determines that the power from the input power source 200 is sampled under certain conditions, and the deviation from the first allowable value is calculated. The master open phase waveform determination unit 114 (open phase waveform determination unit) samples the power under a certain condition, and the analysis result by the master open phase waveform analysis unit 113 (first analysis unit) is normal, a master open-phase waveform (first open-phase waveform) including the first characteristics obtained from the sampled values is determined. Further, the polling open-phase waveform analysis unit 115 (second analysis unit) is obtained from the first characteristic and the value sampled under a certain condition after the determination of the master open-phase waveform (first open-phase waveform) The polling open-phase waveform (second open-phase waveform) is compared with the second characteristic, and it is analyzed whether or not the second characteristic deviates from the second allowable value with respect to the first characteristic. After the master open-phase waveform (first open-phase waveform) is determined, the open-phase waveform determination unit 116 (open-phase waveform determination unit) samples the power under certain conditions, and the polling open-phase waveform analysis unit 115 (second If the analysis result by the analysis unit) does not deviate from the second allowable value, it is determined to be normal, and the main control unit 110 determines that the master open phase waveform determination unit 114 (open phase waveform determination unit) is abnormal. , and when the polling open-phase waveform determination unit 116 (open-phase waveform determination unit) determines that there is an abnormality, an error is notified.

As a result, it is possible to first determine the first open-phase waveform that serves as an index of the stability of the operation of the servo amplifier 100. Therefore, before starting the operation of the servo amplifier 100, it is possible to determine whether or not the servo amplifier 100 is in a state in which malfunction will not occur. I can confirm.

Also, a master open phase waveform is determined based on a manually or automatically set first tolerance, and a polled open phase waveform is normal or abnormal that is compared to the first open phase waveform based on a second tolerance. is determined, the parameter setting of the servo amplifier 100 can be facilitated. In addition, the normality or abnormality of the master phase-loss waveform is determined, and the normality or abnormality of the polling phase-loss waveform is determined. 100 malfunctions can be reliably avoided. In particular, this is effective for avoiding malfunction of the servo amplifier 100 when using a transformer having variations in transformation accuracy.

100 Servo amplifier 110 Main control unit 111 Signal line 112 Single-phase/three-phase setting unit 113 Master open-phase waveform analysis unit 114 Master open-phase waveform determination unit 115 Polling open-phase waveform analysis unit 116 Polling open-phase waveform determination unit 117 Monitor control unit 120 Monitor 200 Input power supply 300 Motor L1, L2, L3, U, V, W Terminals a to e Change point

Claims (6)

a first analysis unit that analyzes whether or not the power from the input power supply deviates from a first allowable value based on values sampled under certain conditions, and outputs an error if it deviates;
The power is sampled under the constant condition, and if the analysis result by the first analysis unit is normal, a phase loss that determines a first phase loss waveform including a first characteristic obtained from the sampled value. a waveform determination unit;
The first characteristic is compared with a second characteristic of a second open-phase waveform obtained from values sampled under the constant condition after the determination of the first open-phase waveform, and the second characteristic is obtained. a second analysis unit that analyzes whether the first characteristic deviates from a second allowable value, and outputs an error if it deviates;
After determining the first open-phase waveform, the power is sampled under a certain condition, and if the analysis result by the second analysis unit does not deviate from the second allowable value, the open-phase waveform is determined to be normal. a determination unit;
When the open phase waveform determination unit determines that there is an abnormality based on the error output from the first analysis unit, and when the open phase waveform determination unit determines that it is abnormal based on the error output from the second analysis unit and a main control unit that notifies an error in each of the cases of The constant condition includes a constant threshold and a constant sampling period,
The first characteristic includes a first frequency and a first duty,
The second characteristic includes a second frequency and a second duty,
The first allowable value includes a manually or automatically set third frequency and third Duty,
The second allowable value includes a manually or automatically set fourth frequency and fourth Duty,
The open phase waveform determination unit binarizes the power using the constant threshold value and the constant sampling period,
The first analysis unit obtains the first frequency and the first duty based on the time difference between the timing at which the sampled value switches from LOW to HIGH and the timing at which the sampled value switches from HIGH to LOW. Analyze whether any or all of the frequency and the first duty are not deviated from any or all of the third frequency and the third duty,
The open phase waveform determination unit binarizes the power using the constant threshold value and the constant sampling period,
The second analysis unit obtains the second frequency and the second duty based on the time difference between the timing at which the sampled value switches from LOW to HIGH and the timing at which the sampled value switches from HIGH to LOW. The servo according to claim 1, characterized by analyzing whether or not any or all of the second frequency and the second duty deviate from any or all of the fourth frequency and the fourth duty. Amplifier. The third frequency and the third duty have values within a certain range,
3. The servo amplifier according to claim 2, wherein the fourth frequency and the fourth duty have values within a certain range. A step of analyzing whether or not the power from the input power supply deviates from the first allowable value based on the values sampled under certain conditions by the first analysis unit, and outputting an error if it deviates. and,
The open-phase waveform determination unit samples the power under the constant condition, and if the analysis result by the first analysis unit is normal, a first missing phase including the first characteristic obtained from the sampled value. determining a phase waveform;
A second analysis unit compares the first characteristic with the second characteristic of the second open-phase waveform obtained from the values sampled under the constant condition after the determination of the first open-phase waveform. and analyzing whether the second characteristic deviates from the second allowable value with respect to the first characteristic, and outputting an error if deviated;
After the first open-phase waveform is determined by the open-phase waveform determination unit, the power is sampled under certain conditions, and if the analysis result by the second analysis unit does not deviate from the second allowable value, a step of determining normal;
When the main control unit determines that the open phase waveform determination unit is abnormal based on the error output from the first analysis unit, and the open phase waveform determination unit outputs the error output from the second analysis unit and a step of notifying an error in each of the cases where an abnormality is determined based on the open phase determination method. The constant condition includes a constant threshold and a constant sampling period,
The first characteristic includes a first frequency and a first duty,
The second characteristic includes a second frequency and a second duty,
The first allowable value includes a manually or automatically set third frequency and third Duty,
The second allowable value includes a manually or automatically set fourth frequency and fourth Duty,
A step of binarizing the power using the constant threshold value and the constant sampling period by the open phase waveform determination unit;
The first analysis unit obtains the first frequency and the first duty based on the time between the timing at which the sampled value switches from LOW to HIGH and the timing at which the sampled value switches from HIGH to LOW, A step of analyzing whether any or all of the first frequency and the first duty are deviated from any or all of the third frequency and the third duty;
A step of binarizing the power using the constant threshold value and the constant sampling period by the open phase waveform determination unit;
The second analysis unit obtains the second frequency and the second duty based on the time between the timing at which the sampled value switches from LOW to HIGH and the timing at which the sampled value switches from HIGH to LOW, The step of analyzing whether any or all of the second frequency and the second duty are not deviated from any or all of the fourth frequency and the fourth duty. Item 5. The open phase determination method according to Item 4. The third frequency and the third duty have values within a certain range,
The open phase determination method according to claim 5, wherein the fourth frequency and the fourth duty have values within a certain range.

Images