JP2567053B2 - Elevator controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to an elevator control device.

(Prior Art) As an elevator control device for controlling by an inverter device, a device as shown in FIG. 5 is conventionally known. This conventional elevator controller is a three-phase AC power supply 1
And a rectifier circuit 2 for converting this three-layer AC power supply 1 into DC
A smoothing capacitor 3 for smoothing the output from the rectifier circuit 2, an inverter device 4 for controlling a variable voltage and a variable frequency for the DC power supply, and an induction motor 5 driven by the inverter device 4.

Then, with respect to the inverter device 4, a speed control device 7 for controlling the inverter device 4 by comparing the speed command generation device 6 of the elevator and the speed command from the speed command generation device 6 with the actual speed signal of the motor 5. And are provided.

In addition, 8 is a sheave which is rotationally driven by the induction motor 5, 9 is an elevator car, 10 is a counterweight with the elevator car 9, which is connected by a rope 11, and the sheave 8 is rotated by the elevator car. 9 is moved up and down.

In such a conventional elevator control device, the alternating current from the alternating current power supply 1 is subjected to three-phase full-wave rectification by the rectifying circuit 2 and given to the inverter device 4 via the smoothing capacitor 3.

In the inverter device 4, the speed control device 7 controls the frequency of the inverter device 4 by comparing the speed command signal from the speed command device 6 with the actual speed signal of the elevator car 9 to control the rotation speed of the induction motor 5. The elevator car 9 is controlled to a speed that matches the speed command from the speed command device 6.

(Problems to be Solved by the Invention) However, since such a conventional inverter control type elevator control device uses a voltage type inverter device for converting to a DC power source which is a three-phase full-wave rectified AC power source, an input current Has a very high fundamental wave power factor of 0.95, and as a result, the input power increases or decreases in proportion to the output power of the motor, which is determined by the elevator load and speed, and when the power supply voltage decreases, the input current is inversely proportional to it. If the power supply voltage from the electric power company drops during the peak power usage in the summer, the input current will increase, and control will be performed in a direction that further promotes the voltage drop. There has been a problem that the ascending / descending speed significantly decreases with a decrease in the power supply voltage.

The present invention has been made in view of such conventional problems, and limits the input current to the elevator during peak power consumption such as in the summer to prevent a voltage drop, thereby increasing the voltage at the operating speed of the elevator car. It is an object of the present invention to provide an elevator control device capable of suppressing the degree of the decrease due to the decrease.

[Configuration of the Invention] (Means for Solving the Problems) An elevator control device of the present invention is an inverter device for an elevator driving motor, an elevator operating speed command means, and the inverter according to a speed command from the speed command means. Speed control means for controlling the device, means for detecting the power running mode of the elevator, input current limit command input means for inputting a limit command of the elevator device input current, and input current limit command from the input current limit command input means In response to the above, when the power running mode is detected by the power running mode detecting means, there is provided arithmetic processing means for giving a speed limiting command to the speed commanding means so as to limit the input current.

(Operation) In the elevator control device of the present invention, the power running mode detection means predicts an operation in which the input current to the elevator device becomes large, and the arithmetic processing means inputs in response to the limit command input of the elevator device input current. A speed command limiting signal that limits the current is given to the speed command means,
It suppresses the increase of the input current due to the decrease of the power supply voltage and prevents the power supply voltage from dropping extremely.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which reference numerals 1 to
Reference numeral 11 denotes a portion having the same reference numeral in the elevator control device of FIG. 5 described in the conventional example.

In this embodiment, a load detecting device 12 is further provided for the car 9 and an arithmetic processing unit 13 is connected to the speed command device 6.

The load detection device 12 detects the load of the car 9, and the load signal 12A is input to the arithmetic processing device 13.

For the arithmetic processing unit 13, together with the load signal 12A, the detection signal 13A of the elevator ascending / descending operation state.
And an external input current limit command signal 13B are input, and in the arithmetic processing unit 13, an arithmetic process for determining whether or not the input current limit is necessary is performed, and a speed command for limiting the input current is issued to the speed command unit 6. It is connected so as to provide an in-device input current limit command signal 13C for reduction.

The arithmetic processing unit 13 can be configured by a relay sequence, but can also be configured by using a logic IC and further by an arithmetic operation by a microcomputer, particularly when configured by a microcomputer. In addition to the arithmetic processing device 13, the speed command device 6 and the speed control device 7 can be incorporated in one IC so that they can be processed collectively.

The operation of the elevator control device having the above configuration will be described below.

As shown in the flowchart of FIG. 2, it is judged whether or not the external input current limit command signal 13B is input (step S1), and when the external input current limit command signal is given, the load signal 12A from the load detection device 12 is used. Confirm the load (step S2).

Next, the direction of the elevator ascending / descending operation is confirmed by the signal 13A (step 3), and based on these inputs, arithmetic processing is performed to determine whether to perform the input current limiting operation as the device (step S4).

Then, when it is determined by the determination calculation of whether or not the input current limiting operation is performed (step S5), the input current limiting command signal 13 is sent to the speed command device 6.
C is output (step S6).

Here, the determination of the load state will be described in more detail.

(1) In the case of making a judgment by comparing the load with which the car 9 and the counterweight 10 are in equilibrium For example, by providing a microswitch that is turned on at the equilibrium load in the car 9 as the load detection device 12, the car 9 and the counterweight 10 The equilibrium with and can be detected. In other words, for a car 9 with a rated load of 1000 kg,
Overbalance between the car 9 and the weight 10 is 0.
If it is 45 and the load is set to 450 kg and the micro switch is set to turn on, it can be judged that when the micro switch is off, the balance is heavy> the car, and when the micro switch is off, the car is> the balance weight. it can.

Furthermore, when the load detection device 12 is one that outputs the load signal 12A in a continuous amount such as a strain gauge, the load can be determined by comparison with the bias amount such that the overbalance becomes 0.45. it can.

(2) When it is determined that the imbalance between the car 9 and the counterweight 10 is more than a certain value. Two microswitches similar to those used in (1) above as the load detection device 12, for example, a rating, are used. Load capacity is 1000k
g, When the overbalance is 0.45, by setting to turn on at 250kg and 650kg for the loaded load respectively, the output of the microswitch indicates that there is an unbalanced state of ± 200kg or more for the balanced load. Can be determined by. If the number of microswitches set is further increased, finer determination can be made, and in this case, it can be used for software operation processing by the continuous load signal.

Next, the criteria for determining the input current limiting motion according to the rising and falling driving directions of the elevator will be described.

In the case of the determination described in (1) above, for example, when the micro switch as the load detection device 12 is turned off and the balance weight> the car, the input current limiting operation is performed only when the down operation command is issued. If the micro switch is on and the car> balance weight is determined, the input current limiting operation is determined only when the ascending operation command is issued. That is, the input current limiting operation is set only for the mode in which most of the operations are the power running operation.

This is because, for example, in the descending operation at the time of rated loading, most of the operation is in the regenerative operation mode, and in the control device in FIG. 1, the input current from the power source side to the main circuit device side is almost 0 during the regenerative operation, Even if you limit the input current,
This is because it has almost no effect on fluctuations in the power supply voltage.

Further, in the case of the determination described in (2) above, it is possible to make a more detailed determination. That is, if the micro switch is set to the two points described in (2), it is possible to judge three load ranges.

For example, if both 250kg and 650kg micro switches are off, it is judged that the input current limiting operation mode is for the downward operation, and if the micro switch on the 650kg side is on, it is the input current limiting operation mode for the ascending operation. To determine.

This is because the load current between 250kg and 650kg is controlled within the range where the input current is relatively small even in the power running operation.
This is because the voltage drop cannot be suppressed even by limiting the input current.

Furthermore, the equilibrium load detection described in (1) above is also added, and the load range is 250 kg or less, 250 to 450, 450 kg to 650 kg, 6
It is possible to judge in four load ranges of 50 kg or more,
The input current limitation can be divided into two modes, light and heavy.

Note that the input current limit determination processing as these devices is
This signal is sent by the signal line 13B in synchronization with an input current limit command from the outside.When the voltage of the input AC power supply drops significantly, such as during peak summer power consumption, the external input current limit command signal is sent. 13B is given, and the device input current limit command processing operation is executed in such a state.

Further, the external input current limit command signal 13B is not limited to one type of limit command on / off signal,
Two levels are provided according to the magnitude of the voltage drop. At level 1, the input current limiting operation mode “heavy” by the arithmetic processing unit 13 is regulated, and the “light” mode is not regulated.
At level 2, the regulations are further tightened for the input current limiting operation mode "heavy", and at level 1 for the "light" mode.
It is also possible to give the speed command device 6 an input power limit command signal 13C such as to perform a regulation equivalent to.

Furthermore, a speed command procedure based on the determination result of the input current limited operation will be described next.

This is the simplest method of limiting the input current of the elevator main circuit, which is the method of lowering the rated speed of the elevator. In a device with an input current fundamental wave power factor close to 1.0, the magnitude of the input current will drive the motor 5. Since the capacity is almost proportional to the capacity, if the rated speed is reduced, the input current can be reduced in proportion to the ratio. Therefore, when the 10% current reduction command is given, the speed command device 6 may output a command to reduce the speed by about 10%.

However, in a device having a poor power factor of the input current, such as the Citalita Leonard system, the magnitude of the input current does not change so much even if the speed is reduced. Therefore, in such a case, the maximum current peak value during acceleration can be reduced by lowering the acceleration for the elevator,
The input current value can be limited. Note that this method can be similarly applied to a device with a high power factor, and by limiting the input power peak value, input current limitation can be widely achieved.

In this way, the input current limitation is applied only to the operation mode in which the power running operation is performed depending on the elevator load load condition and the operation direction, and it is possible to prevent an extreme decrease in the power supply voltage at the peak power consumption in the summer. .

In the case of this embodiment, since the input current limiting operation as the device is performed in synchronization with the input current limiting command signal from the outside, when the input current limiting command from the outside is not input, that is, the power supply voltage decreases. If not, the input current limiting operation is not performed, so the speed does not decrease in the normal state, and it is possible to reduce service deterioration.

FIG. 3 shows another embodiment of the present invention, and the inverter device 4 shown in FIG. 1 is an embodiment of a voltage type inverter that does not perform power regeneration, but FIG. 3 and FIG. The embodiment shown is provided with inverter devices 14 and 15 capable of performing power regeneration and controlling the power factor of the input current to approximately 1.0. In particular, the inverter device 14 shown in FIG. The inverter device 15 shown in the figure is a current type.

16 in FIG. 3 is an AC reactor, and 17 shown in FIG.
Indicates a DC reactor, and 18 indicates a three-phase capacitor.

In each of the embodiments shown in FIGS. 3 and 4, the load signal from the load detection device 12 for the car 9 is also used.
12A, elevator operation direction signal 13A, the input current limit command signal 13B from the outside is input to the arithmetic processing device 13, the arithmetic processing device 13 performs the determination of the need for input current limitation as a device from these input signals, The determination result is given to the speed command device 6.

Also in these embodiments, as in the embodiment shown in FIG. 1, the power running mode of the elevator is determined by the combination of the load signal and the elevator running direction signal, and AND with the external input current limit command signal 13B is performed. By taking
It operates so as to give an input current limit command signal 13C as a device to the speed command device 6.

That is, in the elevator control devices shown in FIGS. 3 and 4, the power factor is approximately 1.0, and most of the current during regenerative operation is an effective current, and this current affects the power supply voltage drop. On the contrary, it has a function of supplying electric power to building facilities and other loads, and can be used as a whole to improve the voltage drop.

[Effect of the Invention] As described above, according to the present invention, the speed command means is operated so as to limit the input current as the device when the input current limit command is externally applied in the power running mode. Therefore, for example, the power supply voltage decreases at the peak of power consumption in summer, the input current to the inverter device increases in inverse proportion to the decrease in the power supply voltage, and this increase in input current further promotes the voltage decrease. It is possible to suppress the voltage drop and suppress the extreme decrease in the speed of the elevator without performing the control in the direction.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of an embodiment of the present invention, FIG. 2 is a flow chart showing the operation of the above embodiment, FIG. 3 is a block diagram of another embodiment of the present invention, and FIG. FIG. 5 is a block diagram of still another embodiment, and FIG. 5 is a block diagram of a conventional example. 1 ... AC power supply, 2 ... Rectifying circuit 3 ... Smoothing capacitor, 4 ... Inverter device, 5 ... Induction motor, 6 ... Speed command device, 7 ... Speed control device, 8 ... Sheave, 9 ... Car basket , 10 …… Balance weight 12 …… Load detection device, 13 …… Arithmetic processing unit

Claims (1)

(57) [Claims] 1. An inverter device for an elevator driving motor, an elevator operating speed command means, speed control means for controlling the inverter device according to a speed command from the speed command means, and detection of a power running mode of the elevator. Means, input current limit command input means for inputting a limit command of the elevator device input current, and in response to the input current limit command from the input current limit command input means, the power running mode is detected by the power running mode detection means. An elevator control apparatus comprising: arithmetic processing means for giving a speed limit command to the speed command means so as to limit the input current when detected.