JP2000217382A - Elevator employing permanent magnet synchronous motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an erroneous pole position signal, if any, by judging the rationality of a pole position signal corresponding to the pole position of a permanent magnet synchronous motor and an incremental signal corresponding to the rotational angle thereof thereby making a decision whether these two signals are correct or not. SOLUTION: An elevator comprises a pole encoder 8 delivering a pole position signal Pp depending on the pole position of a permanent magnet synchronous motor 1, and an AB phase encoder 9 delivering an incremental signal Ep corresponding to the rotational angle thereof. A control block 10 calculates a phase data θs by taking the pole position signal Pp into a phase calculating block 11 and corrects the phase data θs by taking in the incremental signal Ep. In this regard, phase shift θe of the phase data θs is outputted to a phase abnoramality decision block 18 where a decision is made that the phase is abnormal if the phase shift θe exceeds a specified value and the elevator is stopped and the abnormality is notified. According to the arrangement, safety of elevator system can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevator apparatus using a permanent magnet synchronous motor, and more particularly to a control method for ensuring the reliability of a magnetic pole signal.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 9-9699, a permanent magnet synchronous motor is used as a motor for driving a hoist of an elevator apparatus, and a sensor for detecting the magnetic pole position of the permanent magnet synchronous motor is used. There is disclosed a technique for driving a current-carrying coil by switching the current-carrying coil in accordance with a magnetic pole position signal.

Also, as described in JP-A-3-15283, an incremental encoder having a magnetic pole detection function is used to determine a phase through which a current flows by using both a magnetic pole position signal and an incremental signal. A technology for smoothly rotating a motor has been disclosed.

[0004]

In the prior art, mechanical failures caused by failure of a sensor for detecting the position of a magnetic pole, disconnection of a signal line, external noise, or fluctuation of the pressing force of a roller when a roller is used. There is no means for assuming that an erroneous magnetic pole position signal is generated due to a change in coupling or the like.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a means for detecting the possibility that a magnetic pole position signal is erroneous.
Subject. Further, in the above case, it is a second object to obtain means for determining that the magnetic pole position signal is incorrect.

[0006]

The first object is to output a magnetic pole position signal according to the magnetic pole position of the permanent magnet synchronous motor and to output an incremental signal according to the rotation angle of the permanent magnet synchronous motor. Means can be achieved by determining the rationality of the magnetic pole position signal and the incremental signal, and determining whether the two signals are correct.

Further, a second object is to provide means for outputting a magnetic pole position signal corresponding to the magnetic pole position of the permanent magnet synchronous motor, and means for outputting an incremental signal corresponding to the rotation angle of the permanent magnet synchronous motor, Furthermore, it has a means for judging the abnormality of the incremental signal, judges the rationality of the magnetic pole position signal and the incremental signal, judges whether these two signals are correct or not, and when it is judged that either of them is wrong,
This can be achieved by determining that the magnetic pole position signal is erroneous when the incremental signal is normal by means for determining the abnormality of the incremental signal.

[0008]

FIG. 1 shows a first embodiment of the present invention. The permanent magnet synchronous motor 1 is directly connected to the sheave 2, and by rotating the sheave 2 by the motor 1, the car 4 and the counter weight 5 connected to the rope 3 move up and down to operate as an elevator.

The power supply of the permanent magnet synchronous motor 1 is as follows.
This is performed by an inverter 7 that inputs a power supply 6. In general, since the inverter has three phases, the inverter also generates a three-phase alternating current, and power is distributed and supplied to each phase of the motor. The distribution must be performed according to the magnetic pole position of the permanent magnet synchronous motor 1. Therefore, the magnetic pole encoder 8 is attached to the permanent magnet synchronous motor 1. Separately from this, an encoder 9 for outputting an incremental signal for performing speed detection with high accuracy is also provided.

The magnetic pole position signal Pp by the magnetic pole encoder 8
And the incremental signal Ep by the AB phase encoder 9
Is taken into the control system block 10 indicated by the broken line, and the following control is performed. The control system block 10 includes a microcomputer, a control IC, and the like, and is combined with the inverter 7 to form a control panel for elevator control.

In the control system block 10, the magnetic pole position signal Pp is taken into the phase calculation block 11, where the phase of the current matching the magnetic pole position is selected. Further, the incremental signal Ep is also taken into the phase calculation block 11 at the same time, and the phase data θs is updated by counting the incremental signal Ep. Therefore, if there is no error in both the incremental signal Ep and the magnetic pole position signal Pp, the updated phase data θs should match the phase data θs generated based on the magnetic pole position signal Pp. Only when an error occurs between the incremental signal Ep and the magnetic pole signal pulse Pp for some reason, the phase data θs is corrected by the magnetic pole position signal Pp. Although various algorithms for this correction are conceivable, since they are not the gist of the present invention, the description will be omitted. At this time, the phase shift θe of the phase data θs is output to the phase abnormality determination block 18. The operation of this block will be described later.

The incremental signal Ep is separately applied to a speed calculation block 12, where it is subjected to a differentiation process or a difference process and output as speed data ωs. The speed data is applied to the speed control block 13 together with the speed command ωc, and the speed data is subjected to a calculation in accordance with a deviation between the command and the data, thereby outputting current commands Idc and Iqc. These current commands Idc and Iqc are quantities expressed in a dp coordinate system of a direct axis in the magnet direction of the motor and a horizontal axis in the gap direction.

On the other hand, the current sensor 14 in the inverter 7
Since the current detection values extracted from the above are three phases of Ius, Ivs, and Iws, it is necessary to convert this to a dp coordinate system. Therefore, the three-phase / two-phase coordinate conversion block 15 converts the detected current values Ids and Iqs in the dq coordinate system based on the phase data θe. The operation of this conversion is generally well known as a coordinate conversion operation, and a detailed description thereof will be omitted.

The current commands Idc and Iqc and the detected current values Ids and Iqs are input to a current control block, and voltage commands Vdc and Vqc are output. Since the voltage commands Vdc and Vqc are quantities in the dq axis coordinate system, two-phase three-phase coordinate conversion is performed to allocate the voltages as UVW-phase voltages. This is performed in the two-phase three-phase coordinate conversion block based on the phase data θs. The resulting
A three-phase voltage command is applied to the inverter 7, and a desired voltage is applied to the permanent magnet synchronous motor 1.

With such a configuration, a voltage corresponding to the magnetic pole position of the permanent magnet synchronous motor 1 is applied to each phase, so that the permanent magnet synchronous motor 1 rotates at the speed according to the speed command. The car 4 functions as an elevator by controlling a speed command so that the car 4 moves on a predetermined number of floors.

In the system described above, in order to determine the rationality between the magnetic pole position signal Pp and the incremental signal Ep input to the phase calculation block 11, when the phase shift θe is equal to or larger than a predetermined value Is determined.

FIG. 2 shows an example of the operation of each signal until an abnormality is determined. Incremental signal Ep and phase data θ
s, the magnetic pole position signal Pp, and the change in the abnormality determination flag Fer are schematically shown. In the following description,
In order to make the relationship between the signals easy to understand, it is assumed that the motor is rotating at a constant speed, ignoring the effect of the speed control system.

At the rise of the U-phase signal Ppu of the magnetic pole position signal Pp, the phase data θs is set to 0 degree (hereinafter, all electrical angles), and the phase data θs is set by the incremental signal Ep.
The processing of adding s is performed. From time t1 to t
Up to 3, the incremental signal Ep and the magnetic pole position signal Pp
Since both are correct, the transition of the phase data θs from 360 degrees to 0 degree electrical angle and the rise of the magnetic pole position signal Ppu are at the same time. Therefore, the phase data θs is not corrected, and the phase shift θe is 0. After time t3, an abnormality occurs in the incremental signal Ep, a pulse is missing, and the slope of the increase in the phase data θs decreases.

For this reason, at the rise time t4 of the magnetic pole position signal Ppu, the phase data θs has not reached 360 degrees. However, the correction is forcibly performed by the magnetic pole position signal Ppu, and the phase data θs becomes 0 degrees. At this time, the corrected phase data amount, that is, the difference θe between the phase data θs at time t4 and 360 degrees is the phase shift.

Since the phase shift θe is larger than the allowable value θmax, the abnormality determination flag Fer of (1) becomes “1” at time t4, indicating that an abnormality has occurred.

In this signal example, the incremental signal Ep has an abnormality. However, in the system of this embodiment,
It cannot be determined which signal is abnormal.
Therefore, it is detected that any one of the signals is abnormal, and an alarm is issued to the higher-level elevator operation system. In response to this, the elevator operation system stops the car on the nearest floor, and reports an abnormality of the elevator system to the operation management manager or the like. As described above, according to the embodiment of the present invention, the rationality that the phase shift between the two signals of the magnetic pole position signal and the incremental signal is within the allowable value is determined, and when this is not satisfied, the elevator is stopped as a signal abnormality. However, since an abnormality is reported, there is a great effect that a highly safe elevator system can be provided.

FIG. 2 shows (2) as another judging means of this embodiment. This shows only the abnormality determination flag Fer, and the other signals are the same as in (1). In the abnormality determination of (2), the phase shift θe is equal to the allowable value θmax.
The difference from (1) is that the larger number N is counted. That is, the number N is the allowable number Nm
When ax is reached, the abnormality determination flag Fer is set to "1" to indicate an abnormality. In this example, it is possible to exclude abnormalities that happened once by a less serious cause such as noise. Therefore, there is an effect that unnecessary stoppage of the elevator can be avoided.

Next, FIG. 3 shows another signal operation example.

In this example, the U-phase signal of the magnetic pole position signal Pp
Indicates that the Ppu has become abnormal. After time t3, the magnetic pole position signal Ppu becomes defective and rises at time t3 'later than time t3 of 360 degrees of phase data θs, so that the phase data returns to 0 ° when it advances θe1 at time t3'. Will be returned. Therefore, θe1 is the phase shift,
Since this exceeds the allowable phase shift θmax, the abnormality determination flag Fer becomes “1” at time t3 ′ as shown in (1).

FIG. 2B shows an example in which the determination is made based on the number of abnormalities N based on the same concept as in the example of FIG.

In the above example, the operation performed when the magnetic pole position signal is abnormal is described. However, even in this embodiment, since the incremental signal cannot be distinguished from the abnormal signal, it is determined that either signal is abnormal. To fire. Subsequent processing is the same as in the example of FIG.

Next, another embodiment of the present invention will be described with reference to FIG. This incorporates measures for identifying abnormalities in the incremental signal and the magnetic pole position signal.
Only parts different from FIG. 1 will be described. In this example, the description will be given in consideration of the fact that the actual speed changes due to the operation of the speed control system because the speed deviation has a large effect.

A configuration is adopted in which a deviation between the speed command ωc and the detected speed ωs is taken on the input side of the speed control block 13 for performing speed control, and the speed deviation ωe is inputted to the speed control block 13. Is greater than or equal to the allowable value ωemax, a speed deviation abnormality determination block 19 that sets the speed deviation abnormality flag ωer to “1” is provided, and its output ωer
Into the phase abnormality determination block 18. With this configuration, when it is determined that the phase is abnormal, it can be determined whether the magnetic pole position signal Pp is abnormal or the incremental signal Ep is abnormal.

Hereinafter, the details of this processing will be described based on the operation example of the signal shown in FIG. This figure shows the encoder pulse Ep,
It shows changes in the phase data θs, the magnetic pole position signal Pp, the speed deviation ωe, the speed deviation abnormality determination flag ωer, the time integration value ωert of the speed deviation abnormality flag, and the phase abnormality determination flag Fer.

When the incremental signal Ep fluctuates due to a malfunction of the encoder, the actual speed does not change, but the detected speed apparently decreases, so that the speed deviation ωe changes.
Since the speed control works to suppress this, the fluctuation of the incremental signal Ep is within the range of the response of the speed control system.
The inclination of the phase data θs does not change so much.

However, since the actual speed changes due to the fluctuation of the incremental signal, for example, when the speed is high, the cycle of the magnetic pole position signal Pp becomes short. Therefore, before the phase data θs reaches 360 degrees, the magnetic pole position signal Ppu rises and the phase data θs
Is forcibly returned to 0 degrees. The phase shift θe1 at this time is
If the phase deviation is larger than the allowable phase shift θmax, the phase abnormality determination flag is set to “1”, indicating that one of the magnetic pole signals is an incremental signal.

Up to this point, the process is almost the same as that of the previous embodiment, but the signal in which an abnormality has occurred is specified by taking in the speed deviation ωe and performing the following processing. Speed deviation ω
When e is larger than the allowable speed deviation ωemax, the speed deviation abnormality flag ωer becomes “1”. When the time integration value ωert obtained by integrating this time reaches the allowable integration value ωertmax, it is determined that the speed deviation abnormality is reliable, and the incremental signal Ep is determined.
It can be understood that the phase abnormality determination was performed by the malfunction of (1).

On the other hand, FIG. 6 shows another signal operation example of this embodiment, in which the magnetic pole position signal Pp malfunctions. At time t3, the magnetic pole position signal Pp starts malfunctioning. As a result, at time t4, the U-phase signal Ppu of the magnetic pole position signal Pp rises before the phase data θs reaches 360 degrees, and the phase data θs becomes 0 degrees. Will be returned. Therefore, the phase shift θe1 becomes equal to or larger than the allowable phase shift θemax, and the phase abnormality determination flag Fer becomes “1” at time t4. At this time, since the incremental signal Ep is correct,
The speed deviation ωe is within the allowable speed deviation ωemax, the abnormal speed deviation flag ωer remains “0”, and the time integral ωert of the abnormal speed deviation does not change.

Therefore, it is determined that the malfunction is not a malfunction of the incremental signal Ep.

As described above, according to the present embodiment, it is possible to determine which of the incremental signal Ep and the magnetic pole position signal Pp is abnormal, so that a more detailed failure notification can be made regarding the abnormality of the encoder operation.

In the above embodiment, the method of correcting the phase data by using the U-phase signal of the magnetic pole position signal has been described. However, a method of correcting the phase data by combining other phases or independently is also possible. A similar effect can be obtained with a similar configuration.

Also, the example in which the AB-phase encoder and the magnetic pole encoder are respectively provided with individual encoders has been described.
Even if these functions are provided in the same encoder, if the failure of each signal occurs independently,
It goes without saying that a similar effect can be obtained with a similar configuration.

Further, it is a known technique to detect an electric or magnetic physical quantity such as a voltage and a current of a permanent magnet synchronous motor and to estimate a magnetic pole position. It is possible to determine whether the magnetic pole position signal is correct or not by performing the same processing using the configuration of the present invention.

[0039]

According to the present invention, by determining the rationality between the incremental signal and the magnetic pole position signal, if there is a possibility that the magnetic pole position signal may be erroneous, the permanent magnet synchronous motor can be detected. It is possible to appropriately cope with a malfunction of the magnetic pole signal in the used elevator apparatus, and to enhance the reliability of the elevator apparatus.

Further, by providing a function of judging a malfunction of the incremental signal, only a malfunction of the magnetic pole signal can be detected, and the reliability of the elevator apparatus using the permanent magnet synchronous motor can be further improved. It has the effect of being able to.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of an elevator apparatus according to an embodiment of the present invention.

FIG. 2 is a waveform chart showing an example of a signal operation in the embodiment of the present invention.

FIG. 3 is a waveform chart showing another signal operation example in the embodiment of the present invention.

FIG. 4 is a circuit diagram of an elevator apparatus according to another embodiment of the present invention.

FIG. 5 is a waveform chart showing an example of a signal operation in another embodiment of the present invention.

FIG. 6 is a waveform chart showing another signal operation example in another embodiment of the present invention.

[Explanation of symbols]

1: permanent magnet synchronous motor, 8: magnetic pole encoder, 9: A
B-phase encoder, 11: phase calculation block, 18: phase abnormality determination block.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Noboru Arahori 1070 Ma, Hitachinaka-shi, Ibaraki F-term in Mito Plant, Hitachi, Ltd.F-term (reference) BB12 DA07 DB07 EB01 UA01 XA04 XA05 XA06 XA13

Claims (6)

[Claims] 1. A permanent magnet synchronous motor comprising a rotor provided with a permanent magnet, a stator provided with a winding, a counterweight and a car are connected via a rope, and the rope is driven by a hoist. A rope-type elevator hoist that moves the car up and down is directly connected to the permanent magnet synchronous motor, and outputs a magnetic pole position signal corresponding to a magnetic pole position of the permanent magnet synchronous motor; Means for outputting an incremental signal according to the rotation angle of the motor,
An elevator apparatus using a permanent magnet synchronous motor, wherein a rationality between the magnetic pole position signal and the incremental signal is determined, and whether the two signals are correct or not is determined. 2. An elevator apparatus using a permanent magnet synchronous motor according to claim 1, wherein a timing at which said magnetic pole position signal appears is measured by measuring said incremental signal to calculate the magnetic pole position signal. When the difference between the appearance time and the predicted time becomes equal to or more than a predetermined value, a permanent magnet synchronous motor is used, which determines that either the incremental signal or the magnetic pole position signal is incorrect. Elevator equipment. 3. An elevator apparatus using a permanent magnet synchronous motor according to claim 1 or 2, further comprising means for judging abnormality of said incremental signal, and measuring said incremental signal to determine said magnetic pole position. Predicting the timing of the appearance of the signal, if the difference between the timing of the appearance of the magnetic pole position signal and the predicted timing is equal to or greater than a predetermined value, if the incremental abnormality determination means is determined to be abnormal,
An elevator apparatus using a permanent magnet synchronous motor, wherein it is determined that the incremental signal is incorrect, and when it is not determined that the signal is abnormal, the magnetic pole position signal is determined to be incorrect. 4. An elevator apparatus using a permanent magnet synchronous motor according to claim 3, wherein the speed is detected by the incremental signal, and a speed deviation from a speed command is calculated to reduce the speed deviation. When the time when the speed deviation exceeds a predetermined value exceeds a predetermined time, it is determined that the speed deviation is abnormal, and by measuring the incremental signal, the timing at which the magnetic pole position signal appears When the difference between the time when the magnetic pole position signal appears and the predicted time is equal to or more than a predetermined value, when the speed deviation is abnormal, it is determined that the incremental signal is incorrect,
An elevator apparatus using a permanent magnet synchronous motor, wherein it is determined that the magnetic pole position signal is incorrect when the speed deviation is not abnormal. 5. An elevator apparatus using a permanent magnet synchronous motor according to claim 1, wherein the magnetic pole position signal is estimated by detecting an electromagnetic physical quantity of the motor. An elevator apparatus using a permanent magnet synchronous motor. 6. An elevator apparatus using the permanent magnet synchronous motor according to claim 1, wherein when it is determined that one of the magnetic pole position signal and the pulse signal is incorrect. An elevator apparatus using a permanent magnet synchronous motor, characterized in that the degree of the error is determined, and when a predetermined reference value is exceeded, the car is stopped at the nearest floor and a failure is reported. .