JPH04365770A - Control device for elevator - Google Patents

Abstract

PURPOSE:To attain rescue operation of passengers in a cage by detecting abnormality of a main circuit part by an abnormality detecting part to electrically separate the main circuit part of abnormal trouble, and driving a residual normal main circuit part to perform emergency operation by an emergency operational speed pattern. CONSTITUTION:When abnormality signal 67 is inputted in an abnormality detecting part, a signal of level H is output to an OR logical element 48 and a NOT logical element 51. The OR logical element 48 feeds a signal of level H to a NOT logical element 50 and an electric switch element 73. The electric switch element 73 is placed in a switch on-condition to generate a speed pattern at emergency operation time. An output of the NOT logical element 50 becomes a signal of level L fed to an electric switch element 72. The electric switch element 72 is placed in a switch off-condition to end a speed pattern at normal operation time. An output of the NOT logical element 51 becomes a signal of level L to turn off solid state relays 63 to 65 and a main circuit contact.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to an elevator control system using an inverter control system.

0002

2. Description of the Related Art Over the past few years, most elevator control systems have been switched to inverter control systems, from medium- and low-speed elevators to high-speed elevators.

The inverter control method is a control method in which an inverter device that drives the hoisting motor and a power supply side converter device supply power between an AC power source and the hoisting motor via a DC power source.

[0004] Approximately half of all operation modes in elevator systems are regenerative operation modes, so Gareth elevators, which have particularly high mechanical efficiency, use a sine wave PWM (pulse width modulation) controlled transistor converter to return regenerative energy to the power source. Some have adopted it.

[0005] In an inverter device, power transistors and IGBTs (Insulate) are used as main circuit elements.
d Gate Bipolar Transistor
) and other self-extinguishing semiconductor devices are used. Although this semiconductor element has excellent controllability and switching characteristics, it has a problem in that it has a low overload capacity and cannot have a high withstand voltage when compared to a thyristor. In particular, high-speed elevators require an inverter with a large capacity of 100 KVA to 200 KVA, and the induced voltage of the motor becomes high, so the elements are required to have a withstand voltage of 1000 V or more. Also, a current value of 500 A or more is required during acceleration. However, even the largest current power transistor has a rating of about 400 A to 500 A, and in actual use it is necessary to use less than half of this, so the elements must be used in parallel. but,
When used in parallel, current imbalance occurs due to variations in element characteristics, so in order to suppress this as much as possible, we select and match the characteristics of the elements used, and make improvements to the structure of each wiring to unbalance the current. Prevents balance.

[0006]

[Problems to be Solved by the Invention] However, in the method of arranging elements in parallel as described above, it becomes structurally difficult as the number of parallel elements increases, and it is necessary to take a large safety factor with respect to the rating of the elements. Therefore, the practical limit for the number of elements to be arranged in parallel is about four. In this way, in elevators using an inverter control method using power transistors, etc., especially in high-durability and large-capacity applications,
Ensuring reliability involves considerable difficulty. Furthermore, even if such measures are taken, it is difficult to completely eliminate malfunctions; once a malfunction occurs, the elevator will be permanently malfunctioning, trapping passengers in the elevator car, and causing social problems. There is a risk of causing big problems.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to ensure the reliability of the main circuit elements in an elevator using an inverter control system, and to ensure that passengers can be rescued by emergency operation even in the event that the elements are destroyed or the power converter fails. The object of the present invention is to provide an elevator control device that enables the following. [Structure of the invention]

[0008]

[Means for Solving the Problems] In order to achieve the above objects, the present invention provides a main circuit in which at least two sets of power conversion circuits each having an inverter section and a converter section are connected in parallel, and an abnormality in the power conversion circuit. an abnormality detection means that outputs a detection signal when detecting the abnormality detection means; a breaker that is provided in the power conversion circuit and electrically disconnects the power conversion circuit from the main circuit in response to the detection signal; Provided is an elevator control device having an emergency operation speed reference generation circuit that generates an emergency operation speed pattern when an emergency operation speed pattern occurs.

[0009]

[Operation] In the above configuration, under normal conditions, at least two power conversion circuits each having an inverter section and a converter section
Inverter controlled by the main circuit connected in parallel,
In the event of an emergency, the abnormality detection section detects an abnormality in the main circuit section, the malfunctioning main circuit section is electrically disconnected by a circuit breaker, and the remaining normal circuit is driven by the main circuit section, and the abnormal operation speed reference generating circuit is disconnected from the main circuit section. By performing emergency operation using the emergency operation speed pattern, the load on the main circuit elements is reduced, and even if the main circuit element is destroyed and the main circuit section malfunctions, it is possible to operate to rescue passengers in the elevator car. becomes.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the main circuit configuration of an inverter control device according to the present invention.

As shown in FIG. 1, the main circuit configuration system includes a three-phase commercial power supply 1, an AC reactor 2 on the power supply side, power converters 3a and 3b, and an abnormality detector for detecting abnormalities in the power converters 3a and 3b. A detection unit 4, an AC reactor 5 on the motor side, a current detector 6 on the motor side, an induction motor 7, a resolver 8 that detects the speed and rotation angle of the induction motor 7, a main sheave 9, and a main slope. 10 and deflection sheave 11
It is composed of an elevator car 12, a load detector 13 provided under the elevator car, a counterbalance 14, and an inverter control section 15.

Furthermore, the power converters 3a, 3b include charging resistors 16a, 16b for charging the smoothing capacitors 21a, 21b, respectively, and smoothing capacitors 21a, 21b, respectively.
21b, main circuit contactors 18a, 18b, power supply side current detectors 19a, 19b, and converter section 2.
0a, 20b, smoothing capacitors 21a, 21b, voltage detectors 22a, 22b, inverter sections 23a, 23b, converter control sections 24a, 24b, main circuit contactors 25a, 25b on the motor side, and current detection of the reverse power conversion section. It is composed of containers 26a and 26b.

The inverter control unit 15 then operates a speed reference generation circuit 27 that generates a speed reference for the elevator, and compares and calculates the speed command signal from the speed reference generation circuit 27 with the speed signal from the resolver 8. Then, the speed control calculation circuit 28 outputs the first current command signal, and the load signal from the load detector 13 is added to the first current command signal from the speed control calculation circuit 28 to generate the second current command. A load signal addition circuit 29 that outputs a signal, and a vector that performs belt control on the second current command signal from the load signal addition circuit 29 based on the rotor position signal from the resolver 8 and outputs a third current command signal. a braking circuit 30; and a current control calculation circuit 31 that performs a comparison calculation based on the deviation between the third current command signal from the vector control circuit 30 and the current signal from the current detector 6, and outputs a fourth current command signal. PW based on the fourth current command signal from the current control calculation circuit 31.
Sine wave PWM control circuit 3 that performs M (pulse width modulation) control
It is composed of 2. FIG. 2 shows the converter control section 2
FIG. 4 is a block diagram showing the configuration of 4a.

The converter control section 24a includes an abnormal current detector 33a that outputs an abnormal signal to the abnormality detection section 4 when an abnormal current is detected, and a voltage reference generation circuit 34a that generates a voltage command signal to the converter section 20a. , a voltage control calculation circuit 35a that performs a comparison calculation based on the deviation between the voltage command signal from the voltage reference generation circuit 34a and the voltage signal from the voltage detector 22a, and outputs a current command signal; A current control calculation circuit 36a that compares and calculates the current command signal with the current signal obtained from the current detector 19a through the intermediate abnormal current detector 33a and outputs a second current command signal; A sine wave PWM control circuit 37a performs PWM control based on the second current command signal from the circuit 36a. Although the converter control section 24a has been described here, the description of the converter control section 24b will be omitted since it has exactly the same configuration as the converter control section 24a. FIG. 3 is a circuit configuration diagram of the speed reference generation circuit 27 of the abnormality detection section 4 and the inverter control section 15. Figure 3(a),
FIG. 3(b) is a circuit configuration diagram of the abnormality detection section 4.

The circuit configuration of the abnormality detection section 4 includes an operational amplifier 3.
8, 39, resistors 40 to 43, variable resistors 44 and 45 for setting a current detection value for abnormal current detection, OR logic elements 46 to 48, NOT logic elements 49 to 51, and a control power supply (+ ) 52, the control power supply (-) 53, the contactor coils 54, 55, 56 of the main circuit contactors 17a, 18a, 25a, the main circuit contactor 17b,
Contactor coils 57 and 5 of 18b and 25b, respectively
8, 59, and solid state relays 60 to 65. FIG. 3(c) is a circuit configuration diagram of the speed reference generation circuit 27.

The circuit configuration of the speed reference generation circuit 27 includes a normal operation speed reference generation circuit 70 that generates a speed reference during normal operation, an emergency operation speed reference generation circuit 71 that generates a speed reference during emergency operation, and an electric It is composed of switch elements 72 and 73. The operation of the inverter control system with the configuration described above will be explained.

When power is input from the three-phase commercial power supply 1 to the power converters 3a, 3b via the AC reactor 2, the main circuit contactors 17a, 17b are first turned on, and the smoothing capacitors 21a, 21b are charged. . When the smoothing capacitors 21a and 21b are fully charged, the main circuit contactor 18
a, 18b are turned on, and converter sections 20a, 20b are boosted by converter control sections 24a, 24b. Next, the main circuit contactors 25a and 25b are turned on, and the inverter sections 23a and 23b are subjected to PWM control by the inverter control section 15. Based on the control signal from the inverter control section 15, the inverter sections 23a and 23b control the induction motor 7.
to control the speed. Here, the induction machine 7 is supplied with electric power from the inverter section 23a and the inverter section 23b via the AC reactor 5. In other words, the power for driving the induction motor 7 is supplied to the inverters 23a and 2, respectively.
3b is supplied in half.

To explain the operation of the inverter control section 24a, first, the voltage reference generation circuit 34a outputs a voltage command signal to the voltage control calculation circuit 35a. When the voltage control calculation circuit 35a receives the voltage command signal, it compares it with the voltage signal from the voltage detector 22a based on the deviation, and outputs a current command signal to the current control calculation circuit 36a. When the current control calculation circuit 36a receives the current command signal, it compares the current signal obtained from the current detector 19a and checked by the abnormal current detector based on the deviation, and converts the second current command signal into a sine signal. Wave PWM control circuit 37a
Output to. The sine wave PWM control circuit 37a performs PWM control based on the second current command signal, and outputs a control signal to the converter section 20a.

Although the operation of the converter control section 24a has been described here, the operation of the converter control section 24b is not different from that of the converter control section 24a, so a description thereof will be omitted. Next, the operation of the inverter control section 15 will be explained.

First, the speed reference generation circuit 27 outputs a speed command signal to the speed control calculation circuit 28. When the speed control calculation circuit 28 receives the speed command signal, it compares it with the speed signal from the resolver 8 based on the deviation, and outputs a current command signal to the load signal addition circuit 29 . Load detector 1
3 is added to the current command signal, and a second current command signal is output to the vector control circuit 30. When the vector control circuit 30 receives the second current command signal, it performs vector control based on the rotor position signal from the resolver 8 and outputs a third current command signal to the current control calculation circuit 31. When the current control calculation circuit 31 receives the third current command signal, it compares and calculates the current signal from the current detector 6 based on the deviation, and converts the fourth current command signal into a sine wave PWM signal.
Output to the control circuit 32. The sine wave PWM control circuit 32 performs PWM control based on the inputted fourth current command signal, and outputs a control signal to the inverters 23a and 23b. The operations described above are when the elevator operates normally. Next, the operation when an abnormality occurs in the power converter 3b and the elevator switches to operation in the emergency operation mode will be described.

[0021] When the current detected by current detector 19b is overcurrent or undercurrent, converter control unit 24b
An abnormality signal 67 is outputted to the abnormality detection section 4 by the abnormal current detector 33b. Abnormal signal 67 in abnormality detection unit 4
When input, a signal of level H is output from the OR logic element 47 to the OR logic element 48 and the NOT logic element 51. The OR logic element 48 receives the level H from the OR logic element 46.
A signal of level H is input to the NOT logic element 50 and the electric switch element 73. The electric switch element 73 receives a signal of level H and becomes switched on, and the emergency operation speed reference generation circuit 71 generates a speed pattern for emergency operation. Since the NOT logic element 50 receives a signal of level H, the output becomes a signal of level L, and the signal of level L is sent to the electric switch element 72. The electric switch element 72 receives a signal of level L and is switched off, and the normal operation speed pattern from the normal operation speed reference generation circuit 70 is discontinued. The NOT logic element 51 is set to level H by the OR logic element 46.
Since the signal is input, the output is a level L signal,
Solid state relays 63, 64, 65 are turned off, and main circuit contactors 17b, 18b, 25b corresponding to contactor coils 57, 58, 59 are turned off. By turning off the main circuit contactors 17b, 18b, and 25b, the power converter 3b is disconnected from the main circuit, and the elevator
The operation is in the emergency operation mode by only driving the power converter 3a.

Further, when the current 69 detected by the current detector 26b is sent to the abnormality detection section 4 and exceeds the current value set by the variable resistor 45, a signal of level H is output from the operational amplifier 39, and the OR logic element Sent to 47. The OR logic element 47 receives a level H signal from the operational amplifier 39 and outputs a level H signal, and the elevator operates in the same manner as described above to operate in the emergency operation mode only by driving the power converter 3a. Become.

Here, we have explained the operation when an abnormality occurs in the power converter 3b and the elevator switches to the emergency operation mode in which only the power converter 3a is driven. Even in this case, the operation is similarly switched to the emergency operation mode in which only the power converter 3b is driven.

FIG. 4 is a diagram showing speed reference patterns during normal operation and emergency operation of the elevator. Figure 4(a)
is the speed reference pattern during normal operation, and is shown in Fig. 4(b).
is the speed reference pattern during emergency operation.

[0025] The switching operation from normal operation to emergency operation due to an abnormal failure of the power converter 3a or 3b has been described, but the timing is such that an abnormality is detected in the power converter 3a or 3b. In the event of an emergency, two methods are available: one method is to temporarily stop the elevator in normal operation and then perform emergency operation, and the other is to perform emergency operation continuously without stopping the elevator in normal operation. Selection switching can be performed by changing the generation timing of the speed reference pattern by the speed reference generation circuit 71. However, from the viewpoint of safety, it is preferable to temporarily stop the elevator during normal operation and then perform emergency operation. Furthermore, the emergency operation mentioned in the description of the above embodiments refers to a rescue operation such as a stop operation on the nearest floor.

[0026] In this way, by providing the power converters 3a and 3b in parallel, the current and power flowing through each power converter 3a and 3b are halved, making it possible to control the operation of elevators that require large amounts of power. Therefore, the load on the element can be reduced. Furthermore, in the event that one of the power converters fails, emergency operation can be performed by driving only the normal power converter, making it possible to rescue passengers in an emergency and improve reliability. .

[0027]

As described above, according to the present invention, in an elevator using an inverter control system, the reliability of the main circuit element is ensured, and even if the element is destroyed and the power converter malfunctions, passengers can be rescued by emergency operation. Driving becomes possible.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a main circuit configuration system of an inverter control device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of a converter control section of the present invention.

FIG. 3 is a diagram showing a circuit configuration of an abnormality detection section and a speed reference generation circuit according to the present invention.

FIG. 4 is a diagram showing a speed reference pattern of the speed reference generation circuit of the present invention.

[Explanation of symbols]

3a, 3b...Power conversion section
4... Abnormality detection unit 17a, 17b, 18a, 18b, 25
a, 25b...Main circuit contactor 27...Quick stop reference generation circuit 71...Emergency operation speed reference generation circuit

Claims (1)

[Claims] 1. A main circuit in which at least two sets of power conversion circuits having an inverter section and a converter section are connected in parallel; an abnormality detection means for outputting a detection signal when an abnormality in the power conversion circuit is detected; a breaker that is provided in the power conversion circuit and electrically disconnects the power conversion circuit from the main circuit in response to the detection signal; and an emergency operation speed reference generation circuit that generates an emergency operation speed pattern when the detection signal is input. An elevator control device having: