JP2012036003A - Control device for elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure passengers' safety by surely detecting the element failure of an inverter prior to running.SOLUTION: This control device for an elevator includes the inverter 4 having a plurality of switching elements for sequentially driving three phases of a three-phase AC motor 1; current detectors 10a, 10b measuring current values flowing to the respective phases of the three-phase AC motor 1; an inverter failure detecting device 30 detecting the presence of a failure of the inverter 4 based on a current measured result when sequentially operating the respective elements of the inverter 4 so that a current flows to a combination of two phases out of the three phases of the three-phase AC motor 1 prior to running of an elevator car 2; and an operation control device 31 performing prohibition control of running of the elevator car 2 when the failure of the inverter 4 is detected by the inverter failure detecting device 30.

Description

  Embodiments described herein relate generally to an elevator control apparatus including a three-phase AC motor.

  Usually, an elevator is provided with a three-phase AC motor as driving means for a car. This three-phase AC motor has three-phase windings, and rotates by exciting them sequentially. As a device for rotationally driving the three-phase AC motor, a three-phase output type inverter is used.

  This inverter is provided with 6 switching elements (2 per phase x 3) for passing positive and negative currents through the three-phase windings of a three-phase AC motor. In this state, the motor does not rotate normally, and the elevator (car) travels with abnormal vibration.

  An element failure due to such disconnection is referred to as an “off mode failure” or an “open mode failure”. On the other hand, a failure in a state where one of the elements is short-circuited is referred to as an “on-mode failure” or a “short-circuit failure”.

  If it is an on-mode failure, an excessive current flows through the motor, and therefore the presence or absence of the failure can be determined by detecting the current. However, in the case of an off-mode failure, current detection is not known. Therefore, a method is generally used in which, when an abnormal speed is detected during the traveling of the elevator, the elevator is stopped immediately in consideration of the possibility of an off-mode failure.

  In addition, there is a method in which spare switching elements are added in parallel and these switching elements are selectively switched and used in case a switching element fails.

JP 2008-160952 A

  However, if the elevator is driven in a state where the inverter is in the on-mode failure, abnormal vibration occurs, which is dangerous. In addition, the method of detecting an abnormal speed while traveling and performing an emergency stop is not preferable because there is a possibility that the passenger falls.

  Therefore, it is required to reliably detect an element failure of the inverter before traveling to ensure passenger safety.

  An elevator control apparatus according to the present embodiment is an elevator control apparatus that moves a car up and down by driving a three-phase AC motor, and includes a plurality of switching elements for sequentially driving the three phases of the three-phase AC motor. An inverter, a current measuring means for measuring a current value flowing in each phase of the three-phase AC motor, and a current for a combination of two phases of the three phases of the three-phase AC motor before traveling of the car Inverter failure detection means for detecting the presence or absence of failure of the inverter based on the measurement result of the current measurement means when each element of the inverter is operated in order so that current flows, and the inverter failure detection means And a driving control means for prohibiting the traveling of the car when a failure is detected.

FIG. 1 is a diagram illustrating a configuration of an elevator control device according to the first embodiment. FIG. 2 is a diagram showing a configuration of the inverter in the embodiment. FIG. 3 is a flowchart for explaining the flow of processing during elevator travel in the embodiment. FIG. 4 is a flowchart for explaining the flow of an inverter element failure confirmation process in the embodiment. FIG. 5 is a timing chart showing the state of each signal during elevator traveling in the same embodiment. FIG. 6 is a timing chart showing the state of each signal when the inverter failure is confirmed (when normal) in the embodiment. FIG. 7 is a diagram showing the relationship between the switching elements of each phase and the flow of current when the inverter in the embodiment is normal. FIG. 7A shows the switching elements of the U phase and the Y phase turned on. (B) shows the state when the W-phase and X-phase switching elements are turned on, and (c) shows the state when the V-phase and Z-phase switching elements are turned on. Yes. FIG. 8 is a timing chart showing the state of each signal during elevator traveling in the same embodiment. FIG. 9 is a timing chart showing the state of each signal when an inverter failure is confirmed (when a failure occurs) in the same embodiment. FIG. 10 is a diagram showing the relationship between the switching element of each phase and the flow of current when the inverter in the embodiment has an off-mode failure, and FIG. 10A shows the switching element of the U phase and the Y phase. FIG. 4B shows a state when the W-phase and X-phase switching elements are turned on. FIG. 11 is a diagram illustrating a configuration of an elevator control device according to the second embodiment. FIG. 12 is a flowchart for explaining the flow of the inverter element failure confirmation process in the embodiment. FIG. 13 is a timing chart showing the state of each signal when an inverter failure is confirmed (when a failure occurs) in the embodiment. FIG. 14 is a diagram showing the relationship between the switching element of each phase and the current flow when the inverter in the embodiment has an off-mode failure, and FIG. 14A shows the switching element of the U phase and the Y phase. (B) shows the state when the W-phase and X-phase switching elements are turned on, and (c) shows the state when the V-phase and Z-phase switching elements are turned on. Indicates the state. FIG. 15 is a diagram showing the relationship between the switching element of each phase and the flow of current when the inverter in the embodiment has an off-mode failure, and FIG. 15A is a switching element of V phase and X phase. (B) shows the state when the U-phase and Z-phase switching elements are turned on, and (c) shows the state when the W-phase and Y-phase switching elements are turned on. Indicates the state. FIG. 16 is a diagram illustrating a configuration of an elevator control device according to the third embodiment. FIG. 17 is a diagram showing an example of a failure confirmation fixed time set in the storage device in the embodiment. FIG. 18 is a diagram showing an example of a quiet time zone set in the operating state measuring apparatus according to the embodiment.

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

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of an elevator control device according to the first embodiment. In the figure, DE1 to DE3 denote subtracters, and AD1 to AD2 denote adders. “SPC” is a speed control command, “WTC” is a load balancing torque current command, and “ICHK” is an element failure confirmation command. These are output from the operation control device 30 corresponding to the main control device.

  In this apparatus, a three-phase AC motor 1 is provided as an electric motor, and control devices including an inverter 4 are provided as motor driving means. The three-phase AC motor 1 has three-phase windings of a U phase, a V phase, and a W phase, and rotates by exciting them sequentially.

  A sheave 1a is rotatably attached to the rotating shaft of the three-phase AC motor 1, and an electromagnetic brake 1b is disposed so as to brake the rotating shaft that connects the sheave 1a and the three-phase AC motor 1. A rope 1c is wound around the sheave 1a. A cage 2 is connected to one end of the rope 1c, and a suspension weight (counterweight) 3 is connected to the other end.

  When the three-phase AC motor 1 is driven, the sheave 1a rotates, and accordingly, the car 2 and the suspension weight 3 are lifted and lowered in a slidable manner via the rope 1c. At this time, the electromagnetic brake 1b is separated from the sheave 1a.

  A rotation phase detector 5 is attached to the rotation shaft of the three-phase AC motor 1. The rotational phase detector 5 detects the phase “θ” of the rotor of the three-phase AC motor 1. The phase signal “θ” of the rotational phase detector 5 is differentiated by the differentiator 15 and fed back to the speed control system as a speed signal “V” indicating the current speed.

The speed controller 8 is based on the difference signal between the speed signal “V” output from the differentiator 15 and the target speed of the speed command “V ^* ” output from the speed command calculator 7. Torque current for causing the rotation speed of the motor to follow the target speed is calculated and output to the current controller 9 as a torque current command “Iq ^* ”. The current controller 9 outputs a voltage command “Vq ^* ” for supplying a voltage corresponding to the torque current calculated by the speed controller 8 to the three-phase AC motor 1.

  On the other hand, current detectors 10a and 10b are provided in any two phases (here, U phase and W phase) of the U phase, V phase, and W phase constituting the three-phase AC motor 1. When the three-phase AC motor 1 is driven by the voltage supply of the inverter 4, currents “Iu” and “Iw” flowing in the U phase and the W phase are detected by the current detectors 10a and 10b.

  The three-phase AC motor 1 has a characteristic that becomes zero when the three-phase current values are summed. Therefore, the V-phase current “Iv” can be calculated according to the following equation (1).

Iv = −Iu−Iw (1)
The 3-axis / 2-axis converter 11 uses the currents “Iu” and “Iw” detected by the current detectors 10 a and 10 b and the phase signal “θ” of the rotational phase detector 5 to The three-axis current for the phase and the W-phase is converted into a two-axis current of the torque current Iq and its orthogonal axis current “Id”. The conversion formula at this time is shown in the following formula (2).

  Here, when the three-phase AC motor 1 is a permanent magnet synchronous motor, when the phase signal θ is 0 ° and a current of Iu = I, Iv = −I / 2, Iw = −I / 2 flows, it is permanent. The maximum torque is generated in the magnet.

Of these two-axis currents, current control is performed so that the current “Id” follows Id ^* (= 0) and the current “Iq” follows the torque current command “Iq ^* ” from the speed controller 8. The device 9 calculates the biaxial voltage commands “Vd ^* ” and “Vq ^* ”.

The 2-axis / 3-axis converter 12 converts the biaxial voltage commands “Vd ^* ”, “Vq ^* ” into triaxial voltage commands “Vu ^* ”, “Vv ^* ”, “Vw ^* ”, Output to the inverter 4 through the gate drive circuit 6. The conversion formula at this time is shown in the following formula (3).

  The inverter 4 supplies a required voltage to the three-phase AC motor 1 using a method such as PWM (Pulse Width Modulation).

FIG. 2 shows the configuration of the inverter 4.
The + side (P) phase is expressed as UVW, and the-side (N) phase is expressed as XYZ. In the figure, LU, LV, and LW are three-phase coils of the three-phase AC motor 1, and RU, RV, and RW are resistors.

  The inverter 4 is provided with U-phase / X-phase switching elements Qu and Qx, V-phase and Y-phase switching elements Qv and Qy, and W-phase and Z-phase switching elements Qw and Qz, respectively. ing. Qu is a switching element provided on the + side of the U phase, and Qx is a switching element provided on the − side of the U phase. Similarly, Qv is a switching element provided on the + side of the V phase, Qy is a switching element provided on the − side of the V phase, Qw is a switching element provided on the + side of the W phase, and Qz is a switching element provided on the − side of the W phase.

  The gate drive circuit 6 outputs gate signals Gu, Gx, Gv, Gy, Gw, Gz for selectively turning on / off these switching elements Qu, Qx, Qv, Qy, Qw, Qz.

In addition, a load detector 13 for detecting a loaded load in the car is installed below the car 2. The load signal Wt detected by the load detector 13 is given to the weight comparator 14. The weight comparator 14 calculates the weight difference between the car 2 and the suspension weight 3 based on the load signal Wt. When the load suspension torque current command “WTC” is turned on, the unbalance torque corresponding to the weight difference is output as the suspension torque current command “Ibl ^* ” through the first-order lag low-pass filter 16.

Further, the speed abnormality detector 20 indicates that the speed is abnormal when the difference between the speed command “V ^* ” of the speed command calculator 7 and the speed signal “V” output from the differentiator 15 exceeds a certain value. The speed abnormality detection signal “SP_ERR” is output to the operation control device 31. When this speed abnormality detection signal “SP_ERR” is input, the operation control device 31 immediately stops the drive of the motor 1 and urgently stops the elevator (car 2).

  Further, the present apparatus is provided with an inverter failure detection device 30 as a component for detecting an off-mode failure of the inverter 4.

  The inverter failure detection device 30 is positive or negative with respect to the two-phase combination of the three-phase windings of the three-phase AC motor 1 before the elevator travels, that is, immediately before the car 2 starts traveling on each floor. The presence or absence of an off-mode failure is detected based on a current measurement result when a voltage is applied so that a negative current flows. When the inverter failure detection device 30 detects an off-mode failure, the operation control device 31 stops driving the three-phase AC motor 1 and prohibits the traveling of the car 2.

  Hereinafter, the processing operation of the present apparatus relating to the off-mode failure of the inverter 4 will be described in detail.

  FIG. 3 is a flow chart for explaining the flow of processing during elevator travel, and FIG. 4 is a flow chart for explaining the flow of inverter element failure confirmation processing. The processes shown in these flowcharts are basically executed under the operation control device 30 that is the main control device.

(A) When inverter 4 is normal (when off-mode failure does not occur)
FIG. 5 is a timing chart showing the state of each signal during elevator traveling, and FIG. 6 is a timing chart showing the state of each signal at the time of inverter failure confirmation (when normal).

  FIG. 7 is a diagram showing the relationship between each phase switching element and the current flow when the inverter 4 is normal. 7A shows a state when the U-phase and Y-phase switching elements are turned on, FIG. 7B shows a state when the W-phase and X-phase switching elements are turned on, and FIG. A state when the V-phase and Z-phase switching elements are turned on is shown.

  Assume that the elevator car 2 is stopped on the floor. At this time, the electromagnetic brake 1b is in contact with the sheave 1a so that the car 2 does not move in the unbalance direction. In this state, as shown in FIG. 5, when the travel start command “RUN” is output from the operation control device 31 (step S1), the element failure confirmation command “ICHK” is turned on (step S1), and the car Inverter element failure processing is executed before traveling 2 (step S3).

  In the inverter element failure processing, first, in order to confirm the presence / absence of a failure in the switching elements Qu and Qy of the U phase and the Y phase, the gate signals Gu and Gy are received from the gate drive circuit 6 as shown at the timing t1 in FIG. Is output (step S11). Thereby, as shown in FIG. 7A, the switching elements Qu and Qy are turned on, and a current flows in the direction of the arrow.

  At this time, the U-phase current Iu flowing through the windings of the three-phase AC motor 1 is detected by the current detector 10a. The inverter failure detection device 30 compares the absolute value of the current Iu with a preset reference value “Ichk *” (step S12). The value of “Ichk *” may be zero in order to determine whether or not a current is flowing, but it is preferable to set a value slightly higher than zero in consideration of noise.

  If the absolute value of the current Iu is equal to or greater than the reference value “Ichk *” (Yes in step S12), then, in order to confirm whether or not the X-phase and W-phase switching elements Qx and Qw are faulty, at t2 in FIG. As shown in the timing, the gate signals Gx and Gw are output from the gate drive circuit 6 (step S13). Accordingly, as shown in FIG. 7B, the switching elements Qx and Qw are turned on, and a current flows in the direction of the arrow.

  At this time, the W-phase current Iw flowing through the winding of the three-phase AC motor 1 is detected by the current detector 10b. The inverter failure detection device 30 compares the absolute value of the current Iw with a preset reference value “Ichk *” (step S14).

  As a result, if the absolute value of the current Iw is greater than or equal to the reference value “Ichk *” (Yes in step S14), then, in order to confirm whether or not the V-phase and Z-phase switching elements Qv and Qz are faulty, FIG. As shown at the timing t3, the gate signals Gv and Gz are output from the gate drive circuit 6 (step S15). Accordingly, as shown in FIG. 7C, the switching elements Qv and Qz are turned on, and a current flows in the direction of the arrow.

  The V-phase current Iv flowing through the windings of the three-phase AC motor 1 is calculated as Iv = −Iu−Iw using the detection values of the current detectors 10a and 10b. As a result, if the absolute value of the current Iv is greater than or equal to the reference value “Ichk *” (Yes in step S16), it is determined that each element of the inverter 4 is normal, and normal operation processing is executed.

When it is determined that each element of the inverter 4 is normal by the inverter element failure processing before traveling, the load-balancing torque current command “WTC” is turned on as shown in FIG. 3 (step S4). . Along with this, an unbalance torque corresponding to the weight difference between the car 2 and the suspension weight 3 is output as a suspension torque current command “Ibl ^* ” through the first-order lag low-pass filter 16 (step S5).

The suspension torque current command “Ibl ^* ” is given to the current controller 9 as the q-axis current command “Iq ^* ”. When the suspension torque current command “Ibl ^* ” is established, the speed control command “SPC” is turned on (step S6). Thereby, the speed command calculator 7 and the speed controller 8 are activated, and the three-phase AC motor 1 is driven at a predetermined speed (step S7). At this time, the electromagnetic brake 1b is in an open state, and the car 2 moves in the upward or downward direction via the rope 1c as the three-phase AC motor 1 is driven.

  When the car 2 arrives at the destination floor and stops (Yes in step S8), the travel start command “RUN”, the load suspension torque current command “WTC”, and the speed control command “SPC” are turned off, and the next run (Step S9).

(B) When the inverter 4 is in the off mode failure FIG. 8 is a timing chart showing the state of each signal during elevator travel. FIG. 9 is a timing chart showing the state of each signal when an inverter failure is confirmed (when a failure occurs). The point circles in the figure indicate the places where no current was detected.

  FIG. 10 is a diagram showing the relationship between the switching element of each phase and the current flow when the inverter 4 has an off-mode failure. FIG. 10A shows a state when the U-phase and Y-phase switching elements are turned on, and FIG. 10B shows a state when the W-phase and X-phase switching elements are turned on.

  Assume that the elevator car 2 is stopped on the floor. At this time, the electromagnetic brake 1b is in contact with the sheave 1a so that the car 2 does not move in the unbalance direction. In this state, as shown in FIG. 8, when the driving start command “RUN” is output from the operation control device 31 (step S1), the element failure confirmation command “ICHK” is turned on (step S1), and the car Inverter element failure processing is executed before traveling 2 (step S3).

  In the inverter element failure processing, first, in order to confirm the presence / absence of failure of the switching elements Qu and Qy of the U phase and the Y phase, the gate signals Gu and Gy are received from the gate drive circuit 6 as shown at the timing t1 in FIG. Is output (step S11). Thereby, as shown in FIG. 10A, the switching elements Qu and Qy are turned on, and a current flows in the direction of the arrow.

  At this time, the U-phase current Iu flowing through the windings of the three-phase AC motor 1 is detected by the current detector 10a. The inverter failure detection device 30 compares the absolute value of the current Iu with a preset reference value “Ichk *” (step S12).

  If the absolute value of the current Iu is greater than or equal to the reference value “Ichk *” (Yes in step S12), then, in order to confirm whether or not the X-phase and W-phase switching elements Qx and Qw are faulty, As shown in the timing, the gate signals Gx and Gw are output from the gate drive circuit 6 (step S13). Accordingly, as shown in FIG. 10B, the switching elements Qx and Qw are turned on, and a current flows in the direction of the arrow.

  At this time, the W-phase current Iw flowing through the winding of the three-phase AC motor 1 is detected by the current detector 10b. The inverter failure detection device 30 compares the absolute value of the current Iw with a preset reference value “Ichk *” (step S14).

  Here, when the absolute value of the current Iw is less than the reference value “Ichk *” (No in step S14), the inverter failure detection device 30 is one of the X-phase and W-phase switching elements Qx and Qw. One or both are determined to be off-mode failure, i.e., disconnected, and a failure detection signal is output to the operation control device 31. When receiving the failure detection signal, the operation control device 31 stops the driving of the three-phase AC motor 1 and prohibits the traveling of the car 2 (step S17).

  In this case, the current flow was checked by driving positively or negatively in the order of “U phase, Y phase” → “X phase, W phase” → “V phase, Z phase”. It is not limited to the order, but may be checked in another order.

  As described above, in the first embodiment, before the car 2 travels, three patterns of three patterns are set so that a positive or negative current flows with respect to a combination of two phases of the three phases of the three-phase AC motor 1. By operating each switching element of the inverter 4 in combination in order, an off-mode failure can be detected, and when an off-mode failure is detected, traveling is immediately prohibited and passenger safety can be ensured.

(Second Embodiment)
Next, a second embodiment will be described.

  In the first embodiment, the presence or absence of an off-mode failure of the inverter 4 can be detected, but it is not known which element has failed. In the second embodiment, the identification and notification of a failure location will be described.

  FIG. 11 is a diagram illustrating a configuration of an elevator control device according to the second embodiment. In addition, the same code | symbol is attached | subjected to the same part as FIG. 1 in the said 1st Embodiment, and the description shall be abbreviate | omitted.

  In the second embodiment, the element failure confirmation command “ICHK” output from the operation control device 31 causes positive and negative currents to flow with respect to a combination of two phases of the three phases of the three-phase AC motor 1. In addition, each switching element of the inverter 4 is operated in order to identify the fault location.

  In addition, a notification device 32 is connected to the operation control device 31, and when an off-mode failure of the inverter 4 is detected, the occurrence of the failure including the failure location is reported to the monitoring center 33. Has been.

  The monitoring center 33 remotely monitors the operation state of the elevators existing in each region via a communication network, and takes measures such as dispatching maintenance personnel to the site when any abnormality is detected. The reporting device 32 has a communication function for the monitoring center 33.

The operation of the second embodiment will be described in detail below.
FIG. 12 is a flowchart for explaining the flow of the inverter element failure confirmation process in the second embodiment. The process of this flowchart is executed in step S2 of FIG.

  FIG. 13 is a timing chart showing the state of each signal when an inverter failure is confirmed (when a failure occurs) in the second embodiment. The point circles in the figure indicate the places where no current was detected.

  As described above, the inverter 4 includes two switching elements Qu and Qx for the U phase and X phase, two switching elements Qv and Qy for the V phase and Y phase, and two switching elements Qw and Qz for the W phase and Z phase. One set is provided. Before the car 2 travels, an element failure confirmation command “ICHK” is output in order to confirm whether or not these elements have failed, and an inverter element failure confirmation process shown in FIG. 12 is executed.

  That is, gate signals of Gu, Gy, Gx, Gw, Gv, Gz, Gx, Gv, Gu, Gz, Gy, and Gw are sequentially output from the gate drive circuit 6 (see t1 to t6 in FIG. 13), and inverter failure detection is performed. It is determined whether or not the absolute value of the current flowing in each phase of the three-phase AC motor 1 is equal to or higher than a preset Ichk * in the device 30 (steps S21 to S32).

  In this case, the U-phase current Iu of the three-phase AC motor 1 is detected by the current detector 10a, and the W-phase current Iw is detected by the current detector 10b. The V-phase current Iv is calculated from Iv = −Iu−Iw using the detection values of the current detectors 10a and 10b. Here, when the absolute value of the current becomes less than Ichk *, the inverter failure detection device 30 sets an error signal of the corresponding phase in a memory (not shown) (steps S41 to S46).

A specific example is shown in FIGS.
FIG. 14 and FIG. 15 are diagrams showing the relationship between the switching element of each phase and the current flow when the inverter 4 is in the off mode failure. 14A shows a state when the U-phase and Y-phase switching elements are turned on, FIG. 14B shows a state when the W-phase and X-phase switching elements are turned on, and FIG. A state when the V-phase and Z-phase switching elements are turned on is shown. FIG. 15A shows a state when the V-phase and X-phase switching elements are turned on, FIG. 15B shows a state when the U-phase and Z-phase switching elements are turned on, and FIG. A state when the W-phase and Y-phase switching elements are turned on is shown.

  Assume that the X-phase switching element Qx has an off-mode failure. When the gate signals Gx and Gw are output, it is determined that one of the X-phase and W-phase switching elements has failed, and the error signals ERRx1 and ERRw1 are set (step S42).

  Subsequently, when the gate signals Gx and Gv are output, it is determined that either the X-phase or V-phase switching element has failed, and the error signals ERRx2 and ERRv2 are set (step S44).

  The inverter failure detection device 30 performs an AND operation on the results of steps S41 to S46, and determines a failure location of the inverter 4 (step S47).

As shown in FIG. 14B and FIG. 15A, when the X-phase switching element Qx has an off-mode failure,
ERRx = ERRx1∩ERRx2
= 1∩1
= 1
Thus, it is determined as “Qx failure”.

  In this way, when a failure in one or more phases of the inverter 4 is detected (Yes in step S48), a failure detection signal specifying the failure location is output to the operation control device 31. When receiving the failure detection signal, the operation control device 31 stops the driving of the three-phase AC motor 1 and prohibits the traveling of the car 2 (step S49).

  In addition, the operation control device 31 activates the reporting device 32 and reports a failure of the inverter 4 to the monitoring center 33 (step S50). At that time, by issuing a report including the fault location, the maintenance staff dispatched from the monitoring center 33 to the site does not have to check each of the six elements incorporated in the inverter 4 one by one. It can be repaired immediately after identifying the device.

  Here, the current flow was checked by driving positively and negatively in the order of “U phase, Y phase” → “X phase, W phase” → “V phase, Z phase”. It is not limited to the order, but may be checked in another order.

  As described above, according to the second embodiment, six patterns (positive three patterns + negative) are generated so that positive and negative currents flow in the combination of two phases of the three phases of the three-phase AC motor 1. By operating each switching element of the inverter 4 in order with a combination of the three patterns on the side, it is possible to reliably detect off-mode failure including the failure location, and immediately prohibit running when a failure is detected. Passenger safety.

  Further, when an off-mode failure is detected, the failure center including the failure location is notified to the monitoring center 33 so that when a maintenance staff arrives at the site, it is possible to know in advance which element has failed. Therefore, repair work can be performed smoothly.

  In the first embodiment as well, the notification device 32 may be provided, and when an off-mode failure is detected, a notification to that effect may be sent to the monitoring center 33.

(Third embodiment)
Next, a third embodiment will be described.

  FIG. 16 is a diagram illustrating a configuration of an elevator control device according to the third embodiment. In addition, the same code | symbol is attached | subjected to the same part as FIG. 11 in the said 2nd Embodiment, and the description shall be abbreviate | omitted. A storage device 34 that stores preset failure detection times and an operating state measurement device 35 that measures the on / off state of the travel start command “RUN” as needed are provided.

  In the first and second embodiments, an off-mode failure of the inverter 4 is confirmed every time the elevator travels. However, considering that the responsiveness will decrease after the travel start command “RUN” is turned on, the failure check is performed periodically, and even if an element failure occurs during that period, some vibration is unavoidable There is also.

  Therefore, as shown in FIG. 17, a time for confirming the failure is set in the storage device 34. In the example of FIG. 17, it is set to check the failure every 3 hours, such as 6:00, 9:00, 12:00, 15:00.

  The operation control device 31 determines whether or not the travel start command “RUN” is output when the time set in the storage device 34 is reached. If the travel start command “RUN” is not output, the operation control device 31 outputs an element failure confirmation command “ICHK” to the gate drive circuit 6 and the inverter failure detection device 30 to confirm the element failure of the inverter 4. . If the travel start command “RUN” is generated during the failure confirmation, the failure confirmation is interrupted, and the device failure confirmation is performed again after waiting for the next elevator stop timing.

  Alternatively, the operating state measuring device 35 may measure the on / off state of the travel start command “RUN” at any time, and learn the quiet hour of the day from the measurement result. FIG. 18 shows an example of a quiet time zone. In this example, “6: 00 to 7:00”, “10: 00 to 11:00”, “14: 00 to 15:00”,... Are set as the off-hours.

  The operation control device 31 confirms that the travel start command “RUN” is not output during the quiet time set in the operating state measuring device 35, and causes an element failure to the gate drive circuit 6 and the inverter failure detection device 30. A confirmation command “ICHK” is output, and the element failure of the inverter 4 is confirmed. If the travel start command “RUN” is generated during the failure confirmation, the failure confirmation is interrupted, and the device failure confirmation is performed again after waiting for the next elevator stop timing.

  As described above, according to the third embodiment, the traveling state of the car 2 is confirmed when the preset time or quiet time comes, and the elements of the inverter 4 when the car 2 is stopped. By performing the failure check, it is possible to detect the off-mode failure of the inverter 4 without reducing the responsiveness at the start of traveling.

  As described above, according to these embodiments, there is provided an elevator control device that can reliably detect an element failure of an inverter before traveling to ensure passenger safety.

  In each of the above embodiments, the case where an off-mode failure of an inverter used as a drive source for an elevator is detected has been described. However, an inverter used in another field can be similarly applied.

  Moreover, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Three-phase AC motor, 1a ... Sheave, 1b ... Electromagnetic brake, 1c ... Rope, 2 ... Car, 3 ... Suspension weight, 4 ... Inverter, 5 ... Rotation phase detector, 6 ... Gate drive circuit, 7 ... Speed Command arithmetic unit, 8 ... speed controller, 9 ... current controller, 10a, 10b ... current detector, 11 ... 3-axis / 2-axis converter, 12 ... 2-axis / 3-axis converter, 13 ... car load measuring device , 14 ... Weight comparator, 15 ... Differentiator, 16 ... First-order lag low-pass filter, 20 ... Speed abnormality detector, 30 ... Inverter failure detection device, 31 ... Operation control device, 32 ... Alarm device, 33 ... Monitoring center 34 ... Storage device, 35 ... Operating state measuring device.

Claims (7)

In an elevator control device that moves a car up and down by driving a three-phase AC motor,
An inverter having a plurality of switching elements for sequentially driving the three phases of the three-phase AC motor;
Current measuring means for measuring a current value flowing in each phase of the three-phase AC motor;
Measurement result of the current measuring means when each element of the inverter is operated in order so that a current flows to a combination of two phases of the three phases of the three-phase AC motor before the car travels An inverter failure detection means for detecting the presence or absence of a failure of the inverter based on
An elevator control device comprising: an operation control means for prohibiting the traveling of the car when the inverter failure detection means detects a failure of the inverter. The inverter failure detecting means is
Each element of the inverter is operated in order so that a positive or negative current flows for a combination of two phases of the three phases of the three-phase AC motor, and a reference set in advance in the measurement result of the current measuring means 2. The elevator control device according to claim 1, wherein when there is a combination less than the value, it is determined that a failure has occurred in the inverter.   3. The elevator control device according to claim 2, further comprising a reporting means for reporting to the monitoring center when the inverter failure is detected by the inverter failure detecting means. The inverter failure detecting means is
Each element of the inverter is operated in order so that positive and negative currents flow for a combination of two phases of the three phases of the three-phase AC motor, and a reference set in advance in the measurement result of the current measuring means 2. The elevator control apparatus according to claim 1, wherein when there is a combination less than the value, it is determined that a failure has occurred in the inverter, and a failure location is specified from the combination.   When the inverter failure detecting means detects a failure of the inverter, it further comprises a reporting means for notifying the monitoring center that the inverter including the failed part is broken. The elevator control device according to claim 4. A storage means in which a time for checking an element failure of the inverter is set;
The operation control means includes
When the time set in the storage means is reached, the traveling state of the car is confirmed, and when the car is stopped, an element failure confirmation command is issued to the inverter failure detecting means. The elevator control device according to any one of claims 1, 2, and 4. Measures the operating state of the car and includes operating state measuring means for setting a quiet time period from the measurement result.
The operation control means includes
When it is a quiet time set in the operating state measuring means storage means, the running state of the car is confirmed, and when the car is stopped, the inverter failure detecting means is checked for an element failure. The elevator control device according to claim 1, wherein a command is issued.

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