Elevator control method

Abstract

The present application aims at the problem that the star-sealing contactor is limited by the capacity of the contactor itself in controlling the overspeed of the elevator, and cannot provide enough torque to reduce the elevator to a lower speed, and proposes an elevator control method, which comprises an electronic star-sealing device and a mechanical star-sealing device, and comprises an elevator normal parking control method and an elevator fault parking control method, and the present application utilizes the cooperation of the electronic star-sealing device and the mechanical star-sealing device and the optimization of the control method, the mechanical star-sealing device of the present application is small in selected capacity and saves cost; the electronic star-sealing process can avoid the module damage caused by the too large impact current in the electronic star-sealing process, and the elevator can be more safely electronically star-sealed.

Description

Technical Field

[0001] This invention belongs to the field of elevator technology, and specifically relates to an elevator control method. Background Technology

[0002] With the development of my country's economy and society and the continuous emergence of high-rise buildings, the demand for elevators has also shown a continuous upward trend. As an important transportation machinery, elevators bring convenience to users, but their safety hazards have also gradually attracted attention. For elevator equipment, reasonable design, precision manufacturing, improved installation and commissioning quality, and strengthened daily maintenance are necessary to minimize safety accidents and ensure that elevators can serve passengers safely, reliably, and comfortably. Among elevator safety issues, the danger of elevator slippage caused by insufficient power torque of the elevator motor or failure of the brake system is particularly serious. To prevent uncontrollable slippage, a star-connector was developed. When the elevator slips, the star-connector short-circuits the three phases of the traction machine. Most elevator traction machines use permanent magnet synchronous motors. When a permanent magnet synchronous motor rotates under the action of a non-power source, its mechanical energy is converted into electrical energy, which is equivalent to a generator. When the elevator is in an unloaded upward or heavily loaded downward state and is in a state of sudden loss of control, the counterweight or car drives the main unit to rotate. The permanent magnet synchronous motor acts as a generator, and its three-phase windings become the generator's output. At this time, the sealing contactor is in the released state. The normally closed contact of the sealing contactor short-circuits the three-phase windings of the motor, causing a short circuit in the generator output and a large instantaneous short-circuit current. The motor rotor experiences significant resistance, which acts as a brake, causing the elevator to run slowly and preventing it from overshooting the top or bottom at high speed, thus providing safety protection.

[0003] However, there are still some problems with the use of the sealing contactor: if the elevator slips, although the sealing contactor can limit the speed of the slip, it cannot stop the elevator. Moreover, the selected capacity of the sealing contactor directly determines its ability to limit the slip speed. If the slip speed is too fast, the sealing contactor will not be able to provide enough torque to reduce the elevator to a lower speed, which can easily lead to a safety accident. Summary of the Invention

[0004] This invention addresses the problem that the sealing contactor is limited by the size of the contactor itself in controlling the speed limit of elevator trolleys, and cannot provide sufficient torque to reduce the elevator to a lower speed. It proposes an elevator control method.

[0005] The objective of this invention is achieved through the following technical solution: an elevator control method, comprising an electronic star-sealing device and a mechanical star-sealing device, including a normal elevator stop control method and an elevator fault stop control method:

[0006] Step 1: The elevator control system checks whether the elevator is operating normally.

[0007] Step 2: When the elevator control system detects that the elevator is running normally, it issues an elevator stop command and then stops the elevator according to the normal elevator stop control method.

[0008] Step 3: When the elevator control system detects an elevator malfunction, it stops the elevator according to the elevator malfunction stop control method.

[0009] The fault stop control method is as follows: When the elevator control system detects a fault in the elevator operation, it issues a fault alarm. At the same time as issuing the fault alarm, the elevator control system outputs a command to perform emergency braking and stop the elevator. Furthermore, the elevator control system records the elevator's operating speed V0 at the time the fault alarm occurs. Based on the value of V0, the elevator control system performs the following control on the elevator:

[0010] S1. When V0 > 1.05 times the rated speed of the elevator, the electronic star-sealing device operates. After the electronic star-sealing device reduces the speed of the elevator to 0.05m / s, the electronic star-sealing device stops operating, and the mechanical star-sealing device operates.

[0011] S2. When 0.05m / s < V0 ≤ 1.05 times the rated speed of the elevator, the elevator control system starts from time V0 and operates at intervals T. n The current elevator speed is checked once, where T is time and n is the number of checks. The elevator control system's accelerator and decelerator accelerators are activated. When T... n The elevator speed at +1 is greater than T. n When the elevator's running speed is reached, the accelerator value is incremented by 1. n The elevator speed at +1 is <T n When the elevator is running at a certain speed, the value of the deceleration accumulator is increased by 1.

[0012] The electronic star-sealing device operates when the value of the accelerator accelerator is greater than 5 and the value of the accelerator accelerator is greater than the value of the deceleration accelerator.

[0013] When the value of the deceleration accumulator is greater than 5 and the value of the acceleration accumulator is less than the value of the deceleration accumulator, neither the electronic star-sealing device nor the mechanical star-sealing device will operate.

[0014] Preferably, the elevator control system sets the maximum allowable current for the electronic star-sealing device and detects the current value passing through the electronic star-sealing device during its operation.

[0015] When the detected current value exceeds the maximum value set by the elevator control system, the elevator control system will shut down the drive signal of the electronic star-sealing device for one drive cycle, and automatically start the electronic star-sealing device in the next drive cycle.

[0016] Preferably, the T n and T n If the absolute value of the elevator speed difference is ≤0.02m / s, the accelerator or decelerator will not activate; T n and T n If the absolute value of the elevator speed difference is greater than 0.02 m / s, the accelerator or decelerator will activate by +1.

[0017] Preferably, the interval T is 10ms to 50ms.

[0018] As a preferred option, the elevator's traction machine stops immediately and the brake closes after the emergency braking stop command is issued.

[0019] Preferably, the elevator normal stopping control method is as follows: when the elevator decelerates to zero speed according to the deceleration curve, the elevator stops running, the brake closes, and the mechanical star-sealing device is activated after the brake closes; during the activation of the mechanical star-sealing device, the output current of the elevator traction machine is detected.

[0020] When the output current is less than or equal to the rated current of the mechanical star-sealing device, the mechanical star-sealing device continues to work. When the output current is greater than the rated current of the mechanical star-sealing device, the mechanical star-sealing device switches to the electronic star-sealing device to provide speed limit protection for the elevator.

[0021] Preferably, in the elevator normal parking control method, after the electronic star-sealing device operates and limits the speed of the traction machine, the output current of the traction machine also decreases. When the output current of the traction machine is less than the set ratio value of the rated operating current of the traction machine, the electronic star-sealing device stops operating and the mechanical star-sealing device operates.

[0022] Preferably, the set ratio of the output current of the traction machine is 1% to 10% of the rated operating current of the traction machine.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] By utilizing the coordinated operation of electronic and mechanical star-sealing devices and optimizing the control method, the mechanical star-sealing device of this invention has a small capacity and saves costs.

[0025] The electronic star-sealing process can avoid module damage caused by excessive inrush current during the electronic star-sealing process, making the elevator safer to perform electronic star-sealing. Attached Figure Description

[0026] Figure 1 Flowchart of the dual-star control method for normal elevator stop;

[0027] Figure 2A control flowchart for an elevator exceeding its rated operating speed by more than 1.05 times;

[0028] Figure 3 Control flowchart for accelerating elevator operation in response to elevator malfunction alarm;

[0029] Figure 4 Control flowchart for elevator malfunction alarm and deceleration operation;

[0030] Figure 5 This is a control flowchart for elevator malfunction alarms where the speed change is minimal. Detailed Implementation

[0031] The present invention will be further described below with reference to the embodiments illustrated in the accompanying drawings:

[0032] like Figures 1 to 5 As shown, an elevator control method includes an electronic star-sealing device and a mechanical star-sealing device, comprising a normal elevator stop control method and an elevator fault stop control method:

[0033] Step 1: The elevator control system checks whether the elevator is operating normally.

[0034] Step 2: When the elevator control system detects that the elevator is running normally, it issues an elevator stop command and then stops the elevator according to the normal elevator stop control method.

[0035] Step 3: When the elevator control system detects an elevator malfunction, it stops the elevator according to the elevator malfunction stop control method.

[0036] The normal elevator stop control method is as follows: When the elevator decelerates to zero speed according to the deceleration curve, the elevator stops running, the brake closes, and the mechanical star-locking device is activated after the brake closes; during the activation of the mechanical star-locking device, the output current of the elevator traction machine is monitored.

[0037] When the output current is less than or equal to the rated current of the mechanical star-sealing device, the mechanical star-sealing device continues to operate. This can be further divided into two scenarios: First, the traction machine's output current is zero, meaning the elevator does not slip after a normal stop. In this case, the mechanical star-sealing device acts as a preventative measure, activating to protect the elevator from slippage after it stops. Second, the traction machine's output current is not zero, and the elevator slips after a normal stop, but at a slow speed. Short-circuiting the three-phase windings of the traction machine via the mechanical star-sealing device will not exceed its rated current. The mechanical star-sealing device can then act as a generator, using the rotor resistance to stop the traction machine.

[0038] When the output current exceeds the rated current of the mechanical star-sealing device, to prevent the mechanical star-sealing device from burning out due to overcurrent, it switches to an electronic star-sealing device to limit the elevator's speed. The electronic star-sealing device uses a star-sealing circuit composed of power devices in the three-phase inverter bridge arm, and the power devices can allow a much larger current to pass through than the mechanical star-sealing device.

[0039] In this application, the selection current of the mechanical star-sealing device, i.e., the star-sealing contactor, is the same as the rated operating current of the traction machine. After the electronic star-sealing device operates and limits the speed of the traction machine, the output current of the traction machine also decreases. When the output current of the traction machine is less than the set proportional value of the rated operating current of the traction machine, the electronic star-sealing device stops operating, and the mechanical star-sealing device starts operating.

[0040] The set ratio of the output current of the traction machine when the above-mentioned electronic star-sealing device switches to the mechanical star-sealing device is 1% to 10% of the rated operating current of the traction machine. Users can set it according to the actual effect. In this embodiment, the setting is 5% of the rated operating current of the traction machine.

[0041] The fault stop control method is as follows: When the elevator control system detects a fault in the elevator's operation, it issues a fault alarm. Simultaneously with the alarm, the elevator control system outputs a command to initiate emergency braking, meaning the elevator's traction machine immediately stops and the brake disengages. Furthermore, the elevator control system records the elevator's operating speed V0 at the time of the fault alarm. Based on the value of V0, the elevator control system performs the following controls on the elevator:

[0042] S1. When V0 > 1.05 times the rated speed of the elevator, in order to prevent the mechanical star-sealing device from burning out, the electronic star-sealing device will operate. After the electronic star-sealing device reduces the speed of the elevator to 0.05m / s, the electronic star-sealing device will stop operating and the mechanical star-sealing device will operate.

[0043] S2. When 0.05m / s < V0 ≤ 1.05 times the rated speed of the elevator, the elevator control system starts from time V0 and operates at intervals T. n The current elevator speed is detected once, where T is the time and n is the number of detections. The interval T is set in the range of 10ms to 50ms. In this embodiment, the interval T is 30ms.

[0044] When the elevator control system's accelerator and decelerator are put into operation, when T n The elevator speed at +1 is greater than T. n When the elevator's running speed is reached, the accelerator value is incremented by 1. n The elevator speed at +1 is <T n When the elevator's operating speed is reached, the value of the deceleration accumulator is incremented by 1. n and T nThe calculation of the elevator speed difference of +1 has a certain allowable error, namely T. n and T n If the absolute value of the elevator speed difference is ≤0.02m / s, the accelerator or decelerator will not activate; T n and T n If the absolute value of the elevator speed difference is greater than 0.02 m / s, the accelerator or decelerator will activate by +1.

[0045] When the value of the accelerator accelerator is greater than 5 and the value of the accelerator accelerator is greater than the value of the deceleration accelerator, it is considered that the elevator speed is increasing and the electronic sealing device is activated.

[0046] When the value of the deceleration accumulator is greater than 5 and the value of the acceleration accumulator is less than the value of the deceleration accumulator, it is assumed that the elevator speed is decreasing, and neither the electronic sealing device nor the mechanical sealing device will operate.

[0047] If the accelerator's accumulated value has not yet reached 5, but the start time of V0 has exceeded 3 seconds, the electronic star-sealing device will also be put into operation directly.

[0048] When the V0 speed equals the elevator's rated speed and remains unchanged for a preset time exceeding the elevator control system's timeframe, the electronic star-sealing device operates until the elevator's speed drops to 0.05 m / s. At this point, the electronic star-sealing device stops operating, and the mechanical star-sealing device operates. In this embodiment, the preset time for the elevator system does not exceed 3 seconds.

[0049] The aforementioned elevator control system sets the maximum allowable current for the electronic star-sealing device and detects the current value passing through the electronic star-sealing device during its operation.

[0050] When the detected current value exceeds the maximum value set by the elevator control system, the elevator control system will shut down the drive signal of the electronic star-sealing device for one drive cycle, and automatically start the electronic star-sealing device in the next drive cycle.

[0051] In this invention, after the electronic star-sealing mechanism activates, the elevator control system detects the allowable current value of the electronic star-sealing device during its operation. If the elevator control system detects an overcurrent in the electronic star-sealing device, it automatically shuts off the electronic star-sealing signal for one cycle, and automatically starts it again in the next PWM cycle. Furthermore, during the electronic star-sealing process, the PWM frequency in this embodiment can be increased to 20000Hz. With the continuous development of electronic technology, the switching frequency of the power devices constituting the electronic star-sealing device will further increase, and the operating frequency of the electronic star-sealing device will also further increase. The higher the PWM frequency of the electronic star-sealing device, the more sensitive the control of the current passing through it, the less the duty cycle of the three-phase windings of the traction machine is short-circuited, and the longer the effective time for the traction machine to continuously generate resistance like a generator. Through the above processing, module damage caused by excessive inrush current during the electronic star-sealing process can be avoided. Simultaneously, a resistance torque can be intermittently applied to the traction machine, causing its speed to decrease in a manner similar to a jogging brake, thus enabling the elevator to perform electronic star-sealing more safely.

[0052] This invention utilizes the coordinated operation of electronic and mechanical star-sealing devices and the optimization of control methods to achieve automatic switching between the electronic and mechanical star-sealing devices based on the current. The mechanical star-sealing device of this invention has a small capacity and saves costs.

[0053] The electronic star-sealing process can avoid module damage caused by excessive inrush current during the electronic star-sealing process, making the elevator safer to perform electronic star-sealing.

[0054] The electronic and mechanical sealing devices in this embodiment are both existing technologies, and their system structures are as described in the utility model patent publication number CN209226338U, entitled "Dual Sealing Control Device for Elevators".

[0055] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to replace them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. An elevator control method, comprising an electronic star-sealing device and a mechanical star-sealing device, characterized in that, This includes elevator normal stopping control methods and elevator fault stopping control methods: Step 1: The elevator control system checks whether the elevator is operating normally; Step 2: When the elevator control system detects that the elevator is running normally, it issues an elevator stop command and then stops the elevator according to the normal elevator stop control method. Step 3: When the elevator control system detects an elevator malfunction, it stops the elevator according to the elevator malfunction stop control method. The fault stop control method is as follows: When the elevator control system detects an elevator malfunction, it issues a fault alarm. At the same time as issuing the fault alarm, the elevator control system outputs a command to perform emergency braking and stop the elevator. The elevator control system also records the elevator running speed V0 when the fault alarm occurs. The elevator control system controls the elevator according to the value of V0 as follows: S1. When V0 > 1.05 times the rated speed of the elevator, the electronic star-sealing device operates. After the electronic star-sealing device reduces the speed of the elevator to 0.05m / s, the electronic star-sealing device stops operating, and the mechanical star-sealing device operates. S2. When 0.05 m / s < V0 ≤ 1.05 times the rated speed of the elevator, the elevator control system periodically detects the current elevator speed at intervals T starting from time V0, where T is time and n is the number of detections. The acceleration accelerator and deceleration accelerator of the elevator control system are activated. When T n+1 The elevator's running speed at time T > T n When the elevator's running speed is reached, the accelerator value is incremented by 1. n+1 The elevator's operating speed at time T < T n If the elevator's running speed is n, then the value of the deceleration accumulator is incremented by 1, where n is the number of detections; The electronic star-sealing device operates when the value of the accelerator accelerator is greater than 5 and the value of the deceleration accelerator is greater than the value of the deceleration accelerator. When the value of the deceleration accumulator is greater than 5 and the value of the acceleration accumulator is less than the value of the deceleration accumulator, neither the electronic star-sealing device nor the mechanical star-sealing device will operate.

2. The elevator control method according to claim 1, characterized in that, The elevator control system sets the maximum allowable current for the electronic star-sealing device and detects the current value passing through the electronic star-sealing device during its operation. When the detected current value exceeds the maximum value set by the elevator control system, the elevator control system will shut down the drive signal of the electronic star-sealing device for one drive cycle and automatically start the electronic star-sealing device in the next drive cycle.

3. The elevator control method according to claim 1, characterized in that, The T n and T n+1 If the absolute value of the elevator speed difference is ≤0.02m / s, the accelerator or decelerator will not activate; T n and T n+1 If the absolute value of the elevator speed difference is greater than 0.02 m / s, the accelerator or decelerator will activate by +1.

4. The elevator control method according to claim 1, characterized in that, The interval T is 10ms to 50ms.

5. The elevator control method according to claim 1, characterized in that, Once the emergency braking command is issued, the elevator's traction machine immediately stops running and the brake is engaged.

6. The elevator control method according to claim 1, characterized in that, The normal stopping control method for the elevator is as follows: when the elevator decelerates to zero speed according to the deceleration curve, the elevator stops running, the brake is closed, and the mechanical sealing device is activated after the brake is closed. During the activation of the mechanical star-sealing device, the output current of the elevator's traction machine is monitored: when the output current is less than or equal to the rated current value of the mechanical star-sealing device, the mechanical star-sealing device continues to work; when the output current is greater than the rated current value of the mechanical star-sealing device, the mechanical star-sealing device switches to the electronic star-sealing device to provide speed limit protection for the elevator.

7. The elevator control method according to claim 1, characterized in that, In the elevator normal parking control method, after the electronic star-sealing device limits the speed of the traction machine, the output current of the traction machine also decreases. When the output current of the traction machine is less than the set ratio value of the rated operating current of the traction machine, the electronic star-sealing device stops operating and the mechanical star-sealing device starts operating.

8. The elevator control method according to claim 7, characterized in that, The set percentage of the output current of the traction machine is 1% to 10% of the rated operating current of the traction machine.

Images