JP2004256239A - Remodeling method for hydraulic elevator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a remodeling method for a hydraulic elevator for saving energy, shortening low speed running time when landing at a floor, and performing remodeling inexpensively in a short construction term. <P>SOLUTION: Existing bleed-off circuit 10 and controller are removed. A controller 26 provided with an inverter device 22 for energizing a three-phase induction motor 5 driving a hydraulic pump 4 by alternating current of variable voltage variable frequency, an inverter controller 23 for generating alternating current by controlling the inverter device 22, and a car speed controller 24 for computing a speed command value based on distance up to a target story 11 when an operation command is given, energizing the inverter controller 23 based on the speed command value when performing ascent operation, and energizing a flow rate control valve 8 based on the speed command value when performing descent operation is newly provided to control an existing hydraulic power unit. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of repairing a hydraulic elevator, and more particularly to a repair of a control device that controls a hydraulic power unit.
[0002]
[Prior art]
The hydraulic elevator drives a car in a hoistway up and down by a hydraulic jack, and the hydraulic jack operates by supplying and discharging hydraulic oil from a hydraulic power unit.
FIG. 5 shows a conventional hydraulic power unit of a hydraulic elevator similar to that disclosed in Japanese Patent Application Laid-Open No. 2000-86118, in which an oil tank 61 for storing hydraulic oil, a hydraulic pump 63 and a drive of the hydraulic pump 63 are shown. A three-phase induction motor 62 which raises the car by supplying hydraulic oil from an oil tank 61 to a hydraulic jack, a flow control valve 64 constituting a bleed-off circuit, and discharges hydraulic oil from the hydraulic jack to the oil tank 61 Thus, a flow control valve (not shown) for lowering the car, a conduit 65 for guiding the hydraulic oil to each hydraulic device, and a cage are established by preventing the hydraulic oil from being discharged from the hydraulic jack to the oil tank 61. It comprises a check valve 66 for stopping at a position, and a muffler 67 for reducing the sound generated by the hydraulic oil.
[0003]
When raising the car, the conventional hydraulic elevator first activates the three-phase induction motor 62 to drive the hydraulic pump 63, and circulates the entire amount of discharged hydraulic oil to the oil tank 61 via the flow control valve 64. Let it. Thereafter, the amount of oil supplied to the hydraulic jack is gradually increased by squeezing the flow control valve 64 to gradually reduce the amount of circulating oil, thereby starting the car.
When stopping the car in the ascending operation, first, the throttle of the flow control valve 64 is gradually opened to gradually increase the amount of oil circulating from the hydraulic pump 63 to the oil tank 61, thereby decelerating the car. When a predetermined low speed is reached, the throttle of the flow control valve 64 is kept at a constant speed to operate at a low speed. When the landing position is reached, the flow control valve 64 is closed, the entire amount of hydraulic oil discharged from the hydraulic pump 63 is circulated to the oil tank 61 to stop the car, and then the three-phase induction motor 62 is stopped.
That is, the ascending operation is based on the bleed-off method in which the flow control valve 64 controls the amount of oil in the bypass line. For this reason, the deceleration distance greatly changes depending on the oil temperature and the oil pressure. In order to obtain stable landing accuracy against changes in deceleration distance, the vehicle was decelerated with a sufficient distance from just before the destination floor. Was required.
[0004]
Therefore, in the above-mentioned Japanese Patent Application Laid-Open No. 2000-86118, the hydraulic power unit is provided with an oil temperature sensor 71 for measuring the temperature of the working oil, a hydraulic sensor 72 for measuring the pressure of the pipe line 65, and a microcomputer. A new control device 73 is newly provided, and the detection signals of the sensors 71 and 72 are input to the control device 73 and used as control data to reduce the low-speed traveling time at landing. ing.
Japanese Patent Application Laid-Open No. 8-231145 discloses a speed detecting means for detecting the speed of a car and a rotational speed of an electric motor for driving a hydraulic pump, in place of a bleed-off method in order to avoid a power loss. In order to increase or decrease the discharge amount of the hydraulic pump in accordance with the speed pattern, the inverter device is driven based on the speed detection signal and the rotation speed detection signal to perform variable speed control of the electric motor. I have.
[0005]
[Problems to be solved by the invention]
The conventional method of repairing a hydraulic elevator is configured as described above. In the method disclosed in JP-A-2000-86118, the existing control device is removed while the existing hydraulic power unit is left as it is, and the oil shown in FIG. The temperature sensor 71 and the oil pressure sensor 72 are mounted, and a control device 73 having a microcomputer is newly provided.
For this reason, there is a problem that it takes time to mount the oil temperature sensor 71 and the oil pressure sensor 72. In addition, the bleed-off method has a problem that power is lost since the bleed-off method is continuously used.
Japanese Patent Application Laid-Open No. 8-231145 discloses that a speed detecting means and a rotational speed detecting means are newly attached. For this reason, there was a problem that installation was troublesome. In particular, the installation of the rotation speed detecting means is troublesome, and it may be necessary to remove and newly install the hydraulic power unit. Therefore, there is a problem that the repair work requires time and money, and causes a great trouble for the elevator user.
[0006]
The present invention has been made in order to solve the above-described problems, and aims to save energy and shorten the low-speed traveling time at the time of landing, and at the same time, to make repairs at a relatively low price and with a short construction period. It is an object of the present invention to provide a method of repairing a hydraulic elevator that can be performed.
[0007]
[Means for Solving the Problems]
A method of repairing a hydraulic elevator according to claim 1 of the present invention, comprising removing an existing bleed-off circuit and a control device, and energizing a three-phase induction motor that drives a hydraulic pump with an AC having a variable voltage and a variable frequency. And an inverter control device that controls the inverter device to generate an alternating current.When an operation command is issued, a speed command value is calculated based on the distance to the destination floor. A new control device is provided with a car speed control device that energizes the device and, in the case of descent operation, energizes the flow control valve based on the speed command value, to control the existing hydraulic power unit. is there.
[0008]
According to a second aspect of the present invention, there is provided a method for repairing a hydraulic elevator, wherein the car speed control device according to the first aspect is operated by a reference speed calculated based on a distance to a destination floor of the car, and raising and lowering the car. The speed command value is calculated by comparing the actual speed of the car detected by the existing or newly installed speed detecting means.
[0009]
According to a third aspect of the present invention, there is provided a method for repairing a hydraulic elevator, comprising the steps of calculating the speed of a three-phase induction motor based on an output voltage and an output current of the inverter device. The inverter device is compared with a speed command value and the inverter device is controlled based on the comparison result.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
FIGS. 1 to 4 show a method of repairing a hydraulic elevator according to Embodiment 1 of the present invention. FIG. 1 shows the configuration of the hydraulic elevator after the repair. In the drawing, reference numeral 1 denotes a car, and 2 denotes a hydraulic jack for driving the car 1 up and down via a main rope 2a. 3 is an oil tank, 4 is a hydraulic pump, 5 is a three-phase induction motor for driving the hydraulic pump 4 to supply hydraulic oil from the oil tank 3 to the hydraulic jack 2 to raise the car 1, and 6 is a hydraulic oil pipe 7 is a check valve, 8 is a flow control valve for lowering the car 1 by discharging hydraulic oil from the hydraulic jack 2 to the oil tank 3, and by a closing valve 8b when the electromagnetic coil 8a is deenergized. The pipe line 6 is closed, and when energized, switches to the throttle valve 8c, opens the throttle in proportion to the exciting current value, discharges hydraulic oil from the hydraulic jack 2 to the oil tank 3, and lowers the car 1.
Here, the oil tank 3, the hydraulic pump 4, the three-phase induction motor 5, the pipeline 6, the check valve 7, and the flow control valve 8 constitute a hydraulic power unit 9.
Reference numeral 10 denotes an existing bleed-off circuit, which has been removed by repair work.
[0011]
11 is a floor on which the car 1 is put into service, 13 is a landing button attached to each floor 11, 14 is a car operation panel, and 15 is speed detecting means which operates by raising and lowering the car 1, and here, a pulse of a number proportional to the distance is generated. A generating pulse generator is used.
21 is a converter device, 22 is an inverter device for converting DC to three-phase AC and energizing the three-phase induction motor 5, and 23 is a current detector 25 based on output currents iu, iv, iw and voltage of the inverter device 22. An inverter control device that obtains the speed of the three-phase induction motor 5 and compares it with a command signal of a car speed control device 24 described later to control the output voltage of the inverter device 22 to generate a variable voltage variable frequency alternating current.
24 calculates the car speed command value corresponding to the ascent / descent distance Dou or Dod to the destination floor 11 when the hall button 13 or the car operation panel 14 is operated and a driving command is issued, and in the case of ascending operation, the car speed command value Is a car speed control device that energizes the inverter control device 23 on the basis of the above, and energizes the flow control valve 8 in the case of the descent operation.
Here, the converter device 21, the inverter device 22, the inverter control device 23, the car speed control device 24, and the current detector 25 constitute a newly installed control device 26.
[0012]
FIG. 2 is a block diagram showing details of the car speed control device 24. In the figure, the same symbols as those in FIG. 1 indicate the same parts. When the hall button 13 or the car operation panel 14 is operated to register a call, an operation command is output from the operation command means 31 in order to make the car 1 respond to the call.
(1) In the case of ascending operation When the ascending operation command is output from the operation command means 31, the target distance Dou to the destination floor 11 is calculated by the ascending / descending distance calculating means 32. The switching means 33 inputs a signal from the pulse generator 15 to the rising distance calculating means 34u. Here, the number of pulses is counted, and the traveling distance Du of the car 1 is calculated. The car speed command value calculation means 35u calculates the remaining distance Dru by subtracting the traveling distance Du from the target distance Dou, and outputs a speed command value Vpu corresponding to the remaining distance Dru.
Further, the car speed calculating means 36u receives a signal from the pulse generator 15 via the switching means 33 and outputs a car speed Vcu. A subtraction circuit 37u calculates a difference speed Vu between the speed command value Vpu and the car speed Vcu. The motor speed command value calculating means 38 outputs a motor speed command value Np based on the difference speed Vu. The inverter control device 23 controls the inverter device 22 based on the motor speed command value Np to energize the three-phase induction motor 5, and causes the car 1 to land on the destination floor 11.
[0013]
(2) In the case of the descent operation The descent operation is the same as the ascent operation, and when the descent operation command is output from the operation command means 31, the target distance Dod to the destination floor 11 is calculated by the ascent / descent distance calculation means 32. . The switching means 33 inputs the signal from the pulse generator 15 to the descent distance calculating means 34d. Here, the number of pulses is counted, and the traveling distance Dd of the car 1 is calculated. The car speed command value calculating means 35d calculates the remaining distance Drd by subtracting the traveling distance Dd from the target distance Dod, and outputs a speed command value Vpd corresponding to the remaining distance Drd.
The car speed calculating means 36d receives a signal from the pulse generator 15 via the switching means 33 and outputs a car speed Vcd. The difference speed Vd between the speed command value Vpd and the car speed Vcd is calculated by the subtraction circuit 37d. The valve control means 39 calculates the exciting current Iv based on the differential speed Vd, energizes the electromagnetic coil 8a of the flow control valve 8, discharges the hydraulic oil from the hydraulic jack 2, lowers the car 1, and lowers the destination floor 11 To land.
[0014]
FIG. 3 is a block diagram showing details of the inverter control device 23. In the figure, the same reference numerals as those in FIGS. 1 and 2 indicate the same parts.
The inverter control device 23 calculates the speed of the three-phase induction motor 5 based on the output current and voltage of the inverter device 22, compares the speed with the motor speed command value Np from the car speed control device 24, and outputs the output of the inverter device 22. It controls the voltage. This speed method is so-called sensorless control, and has an advantage that it is not necessary to attach a tachometer to the three-phase induction motor 5 and the existing three-phase induction motor 5 can be used as it is.
[0015]
First, the speed detection method will be described. The three-phase / two-phase conversion circuit 49 converts the output currents iu, iv, iw of the inverter device 22 into two phases of an exciting current component id and a torque current component iq. The secondary magnetic flux calculation first circuit 51 calculates a secondary magnetic flux Φrc from the excitation current component id and the torque current component iq using an equation derived from a current model of the three-phase induction motor 5.
[0016]
On the other hand, the secondary magnetic flux calculation second circuit 52 uses the equations derived from the current model of the three-phase induction motor 5 to calculate the excitation current component id, the torque current component iq, the voltage phase angle θ, and the output voltage of the inverter device 22. A second secondary magnetic flux Φrv is calculated from the command values Vd ^* and Vq ^* . The subtraction circuit 53 calculates the deviation between the secondary magnetic flux Φrc and the second secondary magnetic flux Φrv, and the integration calculation circuit 54 performs integration and phase compensation calculation. The calculation result of the integration calculation circuit 54 is output as the rotational angular velocity ωr of the three-phase induction motor 5. If the secondary magnetic flux Φrc and the second secondary magnetic flux Φrv are equal, the rotational angular velocity ωr will be accurate. If not equal, the output of the subtraction circuit 53 corrects the rotational angular velocity ωr by the integration operation circuit 54.
[0017]
Next, control of the inverter device 22 will be described. The coefficient unit 41 multiplies the motor speed command value Np from the car speed control device 24 by a coefficient determined by the three-phase induction motor 5 to calculate the rotation angular speed command value ωr ^* . The difference between the rotational angular velocity command value ωr ^* and the rotational angular velocity ωr is calculated by the subtraction circuit 42 and is output to the torque current command value calculation circuit 43. The torque current command value calculation circuit 43 calculates a torque current command value iq ^* of the three-phase induction motor 5. The excitation current command value calculation circuit 44 calculates the excitation current command value id ^* of the three-phase induction motor 5. The slip frequency calculation circuit 50 calculates the slip frequency ωs from the excitation current component id and the torque current component iq output from the three-phase to two-phase conversion circuit 49. The addition circuit 45 adds the rotational angular velocity ωr output from the integration operation circuit 54 and the slip frequency ωs to calculate the output frequency ω of the inverter device 22. The integration circuit 47 calculates the phase angle θ by integrating the output frequency ω.
[0018]
The inverter output voltage command value calculation circuit 46 generates an output voltage command value of the inverter device 22 from the exciting current command value id ^* , the torque current command value iq ^* , the output frequency ω, the exciting current component id and the torque current component iq. . The output voltage command value is output as a component Vd ^* having the same phase as the exciting current component id and a component Vq ^* having the same phase as the torque current component iq. The two-phase / three-phase conversion circuit 48 generates three-phase voltage command values Vu ^* , Vv ^* , Vw ^* from the output voltage command values Vd ^* , Vq ^* using the phase angle θ output from the integration circuit 47. , To the inverter device 22. The inverter device 22 outputs a three-phase AC voltage based on the command value to energize the three-phase induction motor 5.
[0019]
FIG. 4 is a flowchart showing the work procedure. In the figure, the same symbols as those in FIG. 1 indicate the same parts. First, after stopping the car 1 on the lowest floor 11, the existing control device is removed in step S11. In step S12, the free-off circuit 10 is removed. If the car speed detector, for example, the pulse generator 15 shown in FIG. 1 is not installed, a new one is installed in steps S13 and S14, and if it is installed, the existing one is used. Move to S15. In step S15, the newly installed control device 26 is attached. Wiring work is performed in step S16. After performing the adjustment work in step S17, a trial operation is performed in step 18 to complete the repair work.
[0020]
According to the first embodiment, since the three-phase induction motor 5 is controlled by the inverter device 22 instead of the bleed-off circuit 10, it is possible to save energy and shorten the low-speed traveling time during landing. it can.
Further, since the so-called sensorless control is used to calculate the speed of the three-phase induction motor 5 based on the output current and voltage of the inverter device 22, there is no need to attach a tachometer to the three-phase induction motor 5, and the existing three-phase The induction motor 5 can be used as it is. Therefore, it can be repaired at a relatively low price and with a short construction period.
In the sensorless control, the speed calculation accuracy may decrease in a low speed region. However, in the first embodiment, the car speed calculation unit 36u calculates the car speed Vcu based on the output signal of the pulse generator 15 in the first embodiment. Since the speed command value Vpu by the car speed command value calculating means 35u is corrected, when the speed detection accuracy of the inverter control device 23 is reduced, the motor speed command value Np is corrected. As a result, speed fluctuation of the car 1 can be suppressed.
[0021]
【The invention's effect】
The present invention is configured as described above, and has the following effects.
A method of repairing a hydraulic elevator according to claim 1 of the present invention, comprising removing an existing bleed-off circuit and a control device, and energizing a three-phase induction motor that drives a hydraulic pump with an AC having a variable voltage and a variable frequency. And an inverter control device that controls the inverter device to generate an alternating current.When an operation command is issued, a speed command value is calculated based on the distance to the destination floor. A new control device is provided with a car speed control device that energizes the device and, in the case of descent operation, energizes the flow control valve based on the speed command value, to control the existing hydraulic power unit. is there.
For this reason, there is an effect that it is possible to save energy and shorten the low-speed traveling time at the time of landing.
[0022]
According to a second aspect of the present invention, there is provided a method for repairing a hydraulic elevator, wherein the car speed control device according to the first aspect is operated by a reference speed calculated based on a distance to a destination floor of the car, and raising and lowering the car. The speed command value is calculated by comparing the actual speed of the car detected by the existing or newly installed speed detecting means.
For this reason, there is an effect that the low-speed traveling time at the time of landing can be reduced.
[0023]
According to a third aspect of the present invention, there is provided a method for repairing a hydraulic elevator, comprising the steps of calculating the speed of a three-phase induction motor based on an output voltage and an output current of the inverter device. The inverter device is compared with a speed command value and the inverter device is controlled based on the comparison result.
For this reason, since it is not necessary to attach a speedometer to the three-phase induction motor, there is an effect that the repair can be performed at a relatively low price and with a short construction period.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a hydraulic elevator after repair according to Embodiment 1 of the present invention.
FIG. 2 is a block diagram showing details of a newly installed car speed control device 24 according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing details of a newly installed inverter control device 23 according to the first embodiment of the present invention.
FIG. 4 is a flowchart showing a procedure of repair work of the hydraulic elevator according to the first embodiment of the present invention.
FIG. 5 is a perspective view showing a conventional hydraulic power unit of a hydraulic elevator.
[Explanation of symbols]
1 car, 2 hydraulic jack, 3 oil tank, 4 hydraulic pump, 5 3 phase induction motor, 6 pipeline, 7 check valve, 8 flow control valve, 9 hydraulic power unit, 10 bleed-off circuit, 11 floor, 13 landing button , 14 car operation panel, 15 pulse generator, 21 converter device, 22 inverter device, 23 inverter control device, 24 car speed control device, 25 current detector, 26 control device, 37 subtraction circuit, 42 subtraction circuit, 45 addition circuit , 53 subtraction circuit.

Claims (3)

An oil tank storing hydraulic oil, a three-phase induction motor, a hydraulic pump driven by the three-phase induction motor to pump and discharge the hydraulic oil from the oil tank, and a hydraulic oil discharged from the hydraulic pump A bleed-off circuit that raises and lowers the car by increasing or decreasing the flow rate of the hydraulic oil to the hydraulic jack by controlling the opening and closing of a bypass circuit that circulates the hydraulic oil to the oil tank, and the hydraulic oil from the hydraulic jack to the oil tank. In a method for repairing a hydraulic elevator including a hydraulic power unit having a flow control valve that lowers the car by discharging the hydraulic power unit and a control device that controls the hydraulic power unit, the existing bleed-off circuit and the control device are removed. Device for generating an AC having a variable voltage and a variable frequency to energize the three-phase induction motor An inverter control device that controls the inverter device to generate the AC, and calculates a speed command value based on a distance to a destination floor when an operation command is issued. The inverter control device is energized, and in the case of a descent operation, a control device including a car speed control device that energizes the flow control valve based on the speed command value is newly installed to control the existing hydraulic power unit. Repair method for hydraulic elevators. The car speed control device compares the reference speed calculated based on the distance to the destination floor of the car with the actual speed of the car detected by the existing or newly installed speed detecting means operated by raising and lowering the car, and executing a speed command. The method according to claim 1, wherein the value is calculated. The inverter control device calculates the speed of the three-phase induction motor based on the output voltage and output current of the inverter device, compares the speed with a speed command value, and controls the inverter device based on the comparison result. Item 2. A method for repairing a hydraulic elevator according to Item 1.

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