Intelligent elevator power generation braking device and traction driving elevator comprising same

Abstract

The invention relates to the fields of industrial automatic control system device manufacturing, intelligent basic general equipment, AI + buildings and the like in the high-end equipment manufacturing industry, in particular to an elevator power generation braking intelligent device and a traction driving elevator comprising the same. The elevator power generation braking intelligent device comprises an excitation module and a power load module. The master control circuit is used for controlling the access switch group to access the excitation module and the power load module to the three-phase asynchronous motor when the out-of-control state of the elevator is monitored, and the excitation module provides excitation current for the three-phase asynchronous motor; a rotor of the three-phase asynchronous motor rotates due to out-of-control of the elevator, and the three-phase asynchronous motor enters a power generation state and outputs electric energy outwards; the electric load module consumes electric energy and generates braking torque for the out-of-control elevator. According to the principle of asynchronous power generation of the three-phase asynchronous motor, the rotating speed of the motor is limited by controlling the output electric energy consumption of the motor, and a novel elevator braking mode is provided.

Description

Technical Field

[0001] The present invention relates to the fields of industrial automatic control system device manufacturing, intelligent basic general equipment, AI+architecture, etc. in the high-end equipment manufacturing industry, and in particular to an intelligent elevator power generation and braking device, including a traction drive elevator thereof. Background Art

[0002] With the construction of high-rise buildings in my country, elevators have been widely used, among which traction-driven elevators are the most widely used.

[0003] Figure 1 It is a schematic diagram of the structure of the prior art traction drive elevator. Figure 1 As shown, the traction rope 4 is wound on the traction wheel, and the traction wheel is driven by the motor 1. The first end of the traction rope is suspended by the rope end assembly 6 to the car 7 carrying passengers, and the second end of the traction rope 4 is suspended by the counterweight device 8 through the guide wheel 5. When the motor 1 is started, the torque output by it is converted into a preset speed through the reducer 3, driving the traction wheel to rotate; the friction between the traction wheel and the traction rope 4 will generate traction, so that the car and the counterweight block move relative to each other, that is, the car rises and the counterweight block falls; the counterweight block rises and the car falls. Under normal circumstances, the counterweight block in the unloaded state is 40% to 50% heavier than the unloaded car. For example, for an elevator with a rated load of 1,000 kg, the counterweight block is 400 to 500 kg heavier than the car when the car is unloaded. In order to ensure the safety of the elevator operation and prevent the uncontrolled movement of the motor, a brake 2 is set in the traction drive elevator.

[0004] However, in the continuous production practice, the applicant found that the brake, especially the brake on the old elevator, is an isolated device with poor reliability. In the case of brake failure, the mass difference between the empty car and the counterweight will cause the car to accelerate upward, and the mass difference between the fully loaded car and the counterweight will cause the car to accelerate downward, and finally overspeed and hit the shaft terminal, causing serious losses, and the victims will be either killed or injured. Summary of the invention

[0005] 1. Technical issues to be solved The present invention is expected to at least partially solve one of the above technical problems.

[0006] 2. Technical Solution The first aspect of the present invention provides an intelligent device for generating electric brakes for an elevator, comprising: an excitation module and an electric load module; a state monitoring module for monitoring the operating state of the elevator; an access switch group connected between the excitation module, the electric load module and the three-phase terminals of a three-phase asynchronous motor; a main control circuit for controlling the access switch group to connect the excitation module and the electric load module to the three-phase asynchronous motor when an out-of-control state of the elevator is detected, wherein: the excitation module provides an excitation current for the three-phase asynchronous motor; the rotor of the three-phase asynchronous motor rotates due to the out-of-control state of the elevator, and the three-phase asynchronous motor enters a power generation state and outputs electric energy to the outside; the electric load module consumes electric energy, and then generates a braking torque for the out-of-control elevator.

[0007] In some embodiments of the present invention, the excitation module includes: N capacitors, N≥2; wherein, an energy storage and release excitation unit is formed by one or more of the N capacitors between two terminals of the three-phase terminals of the three-phase asynchronous motor.

[0008] In some embodiments of the present invention, the excitation module includes: a first capacitor, a second capacitor, and a third capacitor, wherein: the first capacitor is connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor; the second capacitor is connected between the Bth terminal and the Cth terminal of the three-phase asynchronous motor; the third capacitor is connected between the Ath terminal and the Cth terminal of the three-phase asynchronous motor; wherein the capacitance values ​​of the first capacitor, the second capacitor, and the third capacitor are the same or different.

[0009] In some embodiments of the present invention, the three-phase asynchronous motor is an industrial frequency motor, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor satisfy: , where the unit of capacitance C is μF, They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively. K is the coefficient, 500≤K≤10000.

[0010] In some embodiments of the present invention, the three-phase asynchronous motor is a non-industrial frequency motor, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor satisfy: , where: the unit of capacitance C is μF, They are the rated current, rated voltage and rated frequency of the three-phase asynchronous motor respectively. Q is the coefficient, 0.1≤Q≤1.

[0011] In some embodiments of the present invention, the withstand voltage of the first capacitor, the second capacitor and the third capacitor is not less than 110% of the rated voltage of the three-phase asynchronous motor.

[0012] In some embodiments of the present invention, the three-phase asynchronous motor is an industrial frequency motor, whose operating frequency is 50 Hz, the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, 3000≤K≤3500; or, the three-phase asynchronous motor is a non-industrial frequency motor, the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, 0.2≤Q≤0.4.

[0013] In some embodiments of the present invention, the excitation module includes: a fifth capacitor, a sixth capacitor, and a seventh capacitor, wherein: the fifth capacitor and the sixth capacitor are both connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor; the sixth capacitor and the seventh capacitor are both connected between the Bth terminal and the Cth terminal of the three-phase asynchronous motor; the seventh capacitor and the fifth capacitor are both connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor; wherein the capacitance values ​​of the fifth capacitor, the sixth capacitor, and the seventh capacitor are the same or different.

[0014] In some embodiments of the present invention, the capacitance values ​​C of the fifth capacitor, the sixth capacitor, and the seventh capacitor satisfy: ,in, They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively. S is the coefficient, 500≤S≤3000.

[0015] In some embodiments of the present invention, the power load module includes: M impedance elements, M≥1; wherein, at at least one of the three positions between two terminals of the three-phase asynchronous motor, a power load is formed by one or more of the M impedance elements.

[0016] In some embodiments of the present invention, it also includes: a load switch group, the load switch group includes: a first load switch, a second load switch; the power load module includes: a first resistor, a second resistor, and a third resistor, wherein: the first resistor and the third resistor are both connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor through the first load switch; the third resistor and the second resistor are both connected between the Bth terminal and the Cth terminal of the three-phase asynchronous motor through the second load switch; the second resistor and the first resistor are both connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor through the first load switch and the second load switch.

[0017] In some embodiments of the present invention, the main control circuit is further used to: when the elevator is detected to be out of control, set the first load switch and the second load switch to a closed state; when the speed of the three-phase asynchronous motor is detected to drop to a preset first speed lower limit, set at least one of the first load switch and the second load switch to an open state; wherein the first speed lower limit is n down-1 Satisfy: n down-1 ≤0.8n0, where n0 is the rated speed of the three-phase asynchronous motor.

[0018] In some embodiments of the present invention, the first load switch and the second load switch are: relays or transistor choppers; and / or, the resistance values ​​of the first resistor, the second resistor, and the third resistor are the same or different; and / or, the resistance values ​​R of the first resistor, the second resistor, and the third resistor satisfy: , where the resistance value R is in ohms, is the rated voltage of the three-phase asynchronous motor, It is the input power of the elevator's downward motor when the elevator is unloaded, 0.5≤T≤2.

[0019] In some embodiments of the present invention, the resistance values ​​of the first resistor, the second resistor, and the third resistor are the same; the resistance values ​​R of the first resistor, the second resistor, and the third resistor satisfy: .

[0020] In some embodiments of the present invention, the power load module includes: a full-wave rectifier circuit; a chopper, a chopper control module, and a load resistor; wherein the full-wave rectifier circuit full-wave rectifies the three-phase AC power into DC power, and the DC power is connected to the load resistor through the chopper, and the load current is continuously adjusted by adjusting the chopping voltage of the chopper, thereby controlling the braking torque.

[0021] In some embodiments of the present invention, it also includes: an asynchronous power generation starting auxiliary module, which is used to output an excitation pulse to the three-phase asynchronous motor; an access switch group, which is connected between the asynchronous power generation starting auxiliary module and any two of the three-phase terminals of the three-phase asynchronous motor; a main control circuit, which is used to: when it is monitored that the speed of the three-phase asynchronous motor is higher than a preset second speed lower limit, if the three-phase asynchronous motor is not detected to have an output voltage, the main control circuit outputs an excitation pulse to the three-phase asynchronous motor through the asynchronous power generation starting auxiliary module to make the motor enter an asynchronous power generation state; wherein the second speed lower limit is between 50% and 90% of the rated speed of the three-phase asynchronous motor.

[0022] In some embodiments of the present invention, the asynchronous generator starting auxiliary module includes: a DC power supply, whose negative output terminal is connected to one of the three terminals of the three-phase asynchronous motor; a switch component, whose first end is connected to the positive output terminal of the DC power supply, and whose second end is connected to another one of the three terminals of the three-phase asynchronous motor.

[0023] In some embodiments of the present invention, the asynchronous generator starting auxiliary module further includes: a diode, whose cathode terminal is connected to the second terminal of the switch component and whose anode terminal is connected to another of the three terminals of the three-phase asynchronous motor; and / or, the frequency of the excitation pulse f Meet: 0.5kHz≤ f≤5kHz; and / or, the output voltage of the DC power supply is between 10V and 36V; and / or, the switching component is an insulated gate bipolar transistor IGBT.

[0024] In some embodiments of the present invention, the state monitoring module is used to monitor the active power input and rotor rotation in the elevator; the main control circuit is used to determine that the elevator is in an out-of-control state when the following conditions are met: the three-phase asynchronous motor rotates without active power input; the following control logic is executed according to the judgment result: when the out-of-control state of the elevator is not detected, the excitation module and the power load module are kept isolated from the connection terminals connecting the three-phase asynchronous motor and the elevator control cabinet; when the out-of-control state of the elevator is detected, the access switch group is controlled to connect the excitation module and the power load module in parallel to the connection terminals of the three-phase asynchronous motor and the elevator control cabinet.

[0025] In some embodiments of the present invention, the state monitoring module includes: a motor power monitoring module for monitoring the power voltage input to the three-phase asynchronous motor; and a motor rotation monitoring module for monitoring the rotation of the rotor in the three-phase asynchronous motor.

[0026] In some embodiments of the present invention, the motor rotation monitoring module is: a magnetic encoder, which is arranged at the shaft end of the three-phase asynchronous motor, the shaft end is connected to the rotor, and its sampling period T satisfies: T≤20ms; and / or the motor current detection module is a voltage transmitter.

[0027] The second aspect of the present invention provides a traction-driven elevator, comprising: a car; a traction wheel driven by a three-phase asynchronous motor; a traction rope, the middle of which is wound around the traction wheel and the first end is connected to the car; the second end is connected to a counterweight device; the above elevator power generation and braking intelligent device; an upper buffer and a lower buffer, which are respectively arranged at the upper and lower ends of the elevator shaft; wherein, when it is detected that the elevator is in an out-of-control state, the three-phase asynchronous motor enters a power generation state, and the power load module is used as an output load to consume the electric energy output by the three-phase asynchronous motor, generate a braking torque, and slow down the movement speed of the elevator car.

[0028] 3. Beneficial Effects It can be seen from the above technical solution that the present invention has at least one of the following beneficial effects compared with the prior art: 1. The present invention utilizes the principle of asynchronous power generation of three-phase asynchronous motors and limits the rotation speed of the motor by controlling the output power consumption of the motor, thereby limiting the uncontrolled moving speed of the elevator, so that the entire uncontrolled moving speed does not exceed the rated operating speed, ensuring that the braking deceleration does not exceed the preset speed, avoiding serious personal injury or property loss, thereby providing a novel elevator braking method.

[0029] 2. In the present invention, the rotor of the three-phase asynchronous motor usually has residual magnetism. During the rotation of the rotor, the stator coil generates an induced current to charge the first capacitor C1, the second capacitor C2, and the third capacitor C3. The voltage across the three capacitors lags the current by 90°. The three capacitors discharge through the stator coil to provide excitation current, and the motor enters the power generation state.

[0030] In some embodiments of the present invention, by means of capacitor excitation, automatic control of charging / discharging can be achieved, other interventions can be reduced, and reliable starting of the elevator power generation braking intelligent device can be ensured.

[0031] 3. In the present invention, the capacitance values ​​of the first capacitor, the second capacitor and the third capacitor are the same, which can ensure that the three-phase output power of the three-phase asynchronous motor is the same when it is in the generating state, so that the reliability of the entire circuit is higher.

[0032] 4. In the present invention, when the elevator power generation braking intelligent device enters the power generation state, when the magnetic encoder detects that the rotor speed is close to the rated speed, the main control electronic control relays K1 and K2 are energized, and three load resistors - R1, R2, and R3 are connected to start consuming the electric energy output by the three-phase asynchronous motor and generate braking torque.

[0033] Furthermore, when it is found that the speed of the three-phase asynchronous motor drops to 80%, in order to avoid the collapse of the power generation state due to low speed, K1 and K2 are disconnected or K1 and K2 are disconnected at the same time according to the speed drop situation to change the load situation and adjust the braking torque to achieve continuously adjustable power consumption control, thereby more accurately controlling the braking torque.

[0034] 5. In the asynchronous power generation starting auxiliary module of the present invention, a pulse of a cycle close to the rotor rotation speed is introduced into the three-phase asynchronous motor through a DC power supply to magnetize the rotor. After magnetization, the three-phase asynchronous motor can enter a power generation state, ensuring smooth starting of the power generation state.

[0035] 6. Differences compared to specific prior art and the beneficial effects produced (1) CN116891173A CN116891173A provides an elevator and a control method thereof, comprising a car; a traction machine connected to the car; a drive system, comprising a motor, driving the rotation of the traction machine through a transmission shaft; a monitoring system for monitoring the rotation speed of the transmission shaft and the AC power supply current of the motor; and a speed control system, which controls the drive system to reduce the rotation speed when the AC power supply current is lower than a predetermined first current threshold and the rotation speed is higher than a predetermined speed threshold. When the drive system is out of control, the monitoring system, the drive system, and the speed control system of the elevator can cooperate with each other to monitor and control the drive system to reduce the rotation speed of the transmission shaft, so that the traction machine drives the car to rise or fall at a low speed, preventing passengers in the car from being injured.

[0036] Compared with CN116891173A, the intelligent device for generating electric brake of elevator of the present invention has the following advantages: ① DC braking requires continuous power supply, and continuous braking cannot be achieved without power supply, while the generating electric brake of the present invention can achieve braking by self-excitation power generation of the motor, and has weak reliance on power supply. When necessary, the power supply of the main control circuit can be supplied by the asynchronous motor; ② DC braking requires a large braking current at rated speed or even overspeed, and such power supply may not be available in many cases, while the asynchronous generating brake of the present invention can generate braking torque with extremely low power supply. After the power generation state is established, the power supply of the device itself can be supplied by the electric energy generated by the asynchronous motor, thus getting rid of the dependence on external power supply.

[0037] (2) US5070290A In US5070290A, when the power supply is suddenly interrupted during the normal operation of the elevator, the control system will control the inverter to make the elevator enter the deceleration state, and use the power generation state when the inverter outputs negative torque to short-term power the control system, inverter and brake. When the power supply is restored, the elevator returns to normal operation. However, if the power supply is still not restored after the specified time, the brake power supply will be cut off to brake the elevator. In this state, the inverter previously relied on negative torque output to generate power to maintain the deceleration operation of the elevator, which will significantly reduce the running speed of the elevator, and can effectively reduce the burden on the mechanical brake when the mechanical brake intervenes.

[0038] The present invention is applied to the state where the asynchronous motor loses the drive of the inverter and the mechanical brake fails, and establishes the excitation current through the residual magnetism of the motor or establishes the excitation through pulse excitation. In the absence of inverter control, the asynchronous power generation state of the asynchronous motor is used to limit the maximum operating speed of the elevator, so that the elevator can stop relatively safely under the action of the buffer, avoiding serious consequences caused by the speed of the elevator car or counterweight exceeding the design parameters of the buffer when it contacts the buffer.

[0039] (3) CN102712442A CN102712442A is only applicable to synchronous motors, and utilizes the synchronous power generation principle of the synchronous motor stator coil cutting the rotor permanent magnet magnetic field to perform energy consumption braking.

[0040] The motor to which the present invention is applicable is an asynchronous motor, which has no permanent magnet and needs to use an external excitation current to enter an asynchronous power generation state for energy-consuming braking.

[0041] (4) CN103508286A CN103508286A adopts asynchronous electric excitation. The capacitor is installed between the three-phase rectifier bridge and the three-phase full-controlled bridge used for inversion. Its function is to filter the DC power after the three-phase AC power is rectified. Electric excitation is used for the three-phase asynchronous motor excitation. The three-phase full-controlled bridge inverts the DC power into three-phase AC power under the drive of the control system. When the motor rotor speed is higher than the rotation speed of the excitation magnetic field under the drag of external power, it enters the asynchronous power generation state.

[0042] The present invention adopts capacitive excitation, directly connecting three excitation capacitors to the power supply end of the asynchronous motor, and utilizing the characteristics of capacitor current phase leading and voltage phase lagging to automatically adjust the speed of the rotating magnetic field of the excitation magnetic field as the speed of the motor changes, so that the rotation of the excitation magnetic field always lags behind the motor rotor, thereby entering the asynchronous power generation state. This is fundamentally different from the excitation principle of CN103508286A. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a structural schematic diagram of a traction drive elevator in the prior art.

[0044] Figure 2 It is a structural schematic diagram of an intelligent device for elevator power generation and braking according to the first embodiment of the present invention.

[0045] Figure 3 for Figure 2 The diagram shown is a schematic diagram of the triangle connection of capacitors in the excitation module of the elevator generator braking intelligent device.

[0046] Figure 4 It is a structural schematic diagram of an intelligent elevator dynamic braking device according to a second embodiment of the present invention.

[0047] Figure 5 for Figure 4 The diagram shown is a schematic diagram of the star connection of capacitors in the elevator dynamic braking intelligent device.

[0048] Figure 6 It is a structural schematic diagram of an intelligent elevator dynamic braking device according to the third embodiment of the present invention. DETAILED DESCRIPTION

[0049] The present invention utilizes the principle of asynchronous power generation of a three-phase asynchronous motor and limits the rotation speed of the motor by controlling the output power consumption of the motor, thereby limiting the uncontrolled moving speed of the elevator, so that the entire uncontrolled moving speed does not exceed the rated operating speed, ensuring that the braking deceleration does not exceed the preset speed, avoiding serious personal injury or property loss, and thus providing a novel elevator braking method.

[0050] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific implementation methods and with reference to the accompanying drawings.

[0051] The first embodiment of the present invention provides an intelligent device for elevator dynamic braking. Figure 2 This is a schematic diagram of the structure of the intelligent device for elevator power generation and braking according to the first embodiment of the present invention. Figure 2 As shown, the elevator power generation braking intelligent device of this embodiment includes: Excitation module and electrical load module; Status monitoring module, used to monitor the operating status of the elevator; An asynchronous generator starting auxiliary module, used for outputting excitation pulses to the three-phase asynchronous motor; The access switch group is connected between the excitation module, the power load module, the asynchronous generator start auxiliary module and the three-phase terminals of the three-phase asynchronous motor; The main control circuit is used to judge the out-of-control state of the elevator. When the elevator is judged to be out-of-control, the control access switch group is controlled to connect the excitation module and the power load module to the three-phase asynchronous motor, wherein: The excitation module provides excitation current for the three-phase asynchronous motor; The rotor of the three-phase asynchronous motor rotates due to the loss of control of the elevator, and the three-phase asynchronous motor enters the power generation state and outputs electrical energy to the outside; The electric load module consumes the electric energy, thereby generating a braking torque on the out-of-control elevator.

[0052] In this embodiment, the asynchronous power generation start-up auxiliary module is provided to ensure that the power generation state can be started smoothly, and can be omitted in some embodiments of the present invention. In addition, in other embodiments of the present invention, the state monitoring module can also be no longer provided separately, but share the state monitoring modules of other systems in the elevator. Such two variations can also realize the present invention and are also within the protection scope of the present invention.

[0053] The following is a detailed description of each component of the intelligent elevator dynamic braking device of this embodiment.

[0054] In this embodiment, the state monitoring module is used to monitor the active power input and rotor rotation in the elevator, so as to determine the operating state of the elevator. Specifically, the state monitoring module includes: a motor power monitoring module, which is used to monitor the power voltage input to the three-phase asynchronous motor; and a motor rotation monitoring module, which is used to monitor the rotation of the rotor in the three-phase asynchronous motor.

[0055] like Figure 2 As shown, the motor rotation monitoring module is: a magnetic encoder, which is arranged at the shaft end of the three-phase asynchronous motor, the shaft end is connected to the rotor, and its sampling period T satisfies: T≤20ms; the motor current detection module is a voltage transmitter to monitor the power voltage.

[0056] The main control circuit is used to determine that the elevator is in an out-of-control state when the following conditions are met: the three-phase asynchronous motor rotates without active power input. The main control circuit makes the following logical actions based on the judgment: ①When the elevator is not out of control, keep the excitation module and the power load module isolated from the connection terminals of the three-phase asynchronous motor and the elevator control cabinet; ② When the elevator is detected to be out of control, the control access switch group connects the excitation module and the power load module in parallel to the connection terminals of the three-phase asynchronous motor and the elevator control cabinet.

[0057] In the prior art, the elevator's built-in brake device will intervene only when it detects that the elevator's motor is running at a speed exceeding 115% of the rated speed. However, under normal circumstances, the elevator has already moved several meters or even farther at this time, and the elevator door must have been open during this period. If a person is standing with one foot inside the elevator door and the other foot outside, or if a person falls in this interval, then the person will be sheared between the car and the floor door sill, causing a very tragic accident scene.

[0058] In this embodiment, a state monitoring module and a main control circuit are provided. When it is found that the rotor of the motor rotates, and there is no current in the motor coil, and the voltage across the coil does not reach the voltage corresponding to the speed, it is determined that the elevator has unexpected movement. Experiments have proved that due to the use of a magnetic encoder, when the car moving speed reaches 80% of the rated speed within 20ms, the elevator power generation brake device of this embodiment will respond quickly, and then let the elevator enter the power generation brake operation state, limiting the elevator moving speed to not exceed the rated speed. When the elevator car finally squats to the buffer at the bottom or top of the elevator shaft, the speed of the elevator impacting the buffer can meet the design requirements of the elevator buffer, ensuring the personal safety of passengers.

[0059] In this embodiment, the two parameters of active power input and rotor rotation are used to determine the operating state of the three-phase asynchronous motor, but the present invention is not limited thereto. Those skilled in the art should understand that the operating state of the three-phase asynchronous motor can also be monitored by other methods and other parameters, or the elevator power generation and braking intelligent device of the present invention shares the state monitoring components of other systems, which can realize the present invention and are within the protection state of the present invention.

[0060] As mentioned above, during normal operation of the elevator, the excitation module, power load module, and asynchronous generator start auxiliary module are disconnected from the three-phase asynchronous motor; when the elevator is out of control, the excitation module, power load module, and asynchronous generator start auxiliary module are connected to the three-phase asynchronous motor. The "disconnection" and "connection" here are realized by the access switch group controlled by the main control circuit.

[0061] like Figure 2 As shown, in this embodiment, the access switch group includes: a first switch, a second switch, and a third switch, which are respectively connected to the Ath terminal, the Bth terminal, and the Cth terminal of the three-phase asynchronous motor. The three switches are linked and opened or closed at the same time.

[0062] Those skilled in the art should understand that the above structure is only an example, and the access switch group in the present invention can adopt any structure that can realize the controlled connection of the three-phase terminals of the three-phase asynchronous motor, and all of them can realize the present invention and are within the protection scope of the present invention.

[0063] In order to facilitate understanding of the power generation process of the elevator power generation brake intelligent device of this embodiment, the interaction between the electromagnetic field generated by the stator and the electromagnetic field generated by the rotor in the three-phase asynchronous motor is described below. Specifically, the stator generates a magnetic field after the excitation current is passed through it. Due to the elevator out of control, the rotor rotates, and the rotor coil cuts the magnetic field to generate current in the closed loop, and a rotating magnetic field is generated as the rotor rotates. The stator coil cuts the rotating magnetic field to generate electricity.

[0064] In the present invention, the excitation module is used to provide excitation current to the three-phase asynchronous motor of the elevator. The excitation module has two forms: ①The excitation module is realized by capacitor Specifically, the excitation module includes: N capacitors, N≥2, wherein one or more of the N capacitors form an energy storage and discharge excitation unit between two terminals of the three-phase terminals of the three-phase asynchronous motor. This implementation form will be described in detail in this embodiment.

[0065] ②The excitation module is realized by the inverter Figure 3 for Figure 2 The diagram shows the capacitor triangle connection in the excitation module of the elevator power generation brake intelligent device. Figure 2 and Figure 3 As shown, the excitation module includes: a first capacitor C1, a second capacitor C2, and a third capacitor C3, wherein: the first capacitor C1 is connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor; the second capacitor C2 is connected between the Bth terminal and the Cth terminal of the three-phase asynchronous motor; the third capacitor C3 is connected between the Ath terminal and the Cth terminal of the three-phase asynchronous motor. The withstand voltage of the three capacitors should not be less than 118% of the rated voltage of the three-phase asynchronous motor.

[0066] Theoretically, the capacitance values ​​of the first capacitor C1, the second capacitor C2, and the third capacitor C3 are related to the power generation and can be flexibly set within a certain range, but they cannot be too small or too large for the following reasons: ① If the capacitance is set too small, the current that causes the power generation to collapse will be very small. For example: for an 11kW motor, if the capacitance value is selected reasonably, the motor can output about 8kW of power, but if the capacitance is too small, it may collapse at 3kW or 5kW of power generation.

[0067] ② If the capacitance is set too large, the capacitance itself becomes a load of the alternating current, which will affect the efficiency of this embodiment and may also affect the functional realization of other components.

[0068] It should be noted that, for the three-phase asynchronous motor being an industrial frequency motor or a non-industrial frequency motor, the conditions satisfied by the first to third capacitors are different, which are explained below respectively.

[0069] ① The three-phase asynchronous motor is an industrial frequency motor (operating frequency is 50Hz) The capacitance values ​​C of the first capacitor C1, the second capacitor C2, and the third capacitor C3 satisfy:

[0070] The unit of capacitance C is μF. They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively. K is the coefficient, 500≤K≤10000.

[0071] Preferably, 1000≤K≤2000. Optimally, the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, and 3000≤K≤3500.

[0072] ② The three-phase asynchronous motor is a non-industrial frequency motor (the operating frequency is not 50Hz) The capacitance values ​​C of the first capacitor C1, the second capacitor C2, and the third capacitor C3 satisfy:

[0073] Where: The unit of capacitance C is μF, They are the rated current, rated voltage and rated frequency of the three-phase asynchronous motor respectively. Q is the coefficient, 0.1≤Q≤1.

[0074] Preferably, 0.5≤Q≤1. Optimally, the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, and 0.2≤Q≤0.4.

[0075] In this embodiment, the rotor of the three-phase asynchronous motor usually has residual magnetism. During the rotation of the rotor, the stator coil generates an induced current to charge the first capacitor C1, the second capacitor C2, and the third capacitor C3. The voltage across the three capacitors lags the current by 90°. The three capacitors discharge through the stator coil to provide excitation current, and the motor enters the power generation state.

[0076] Regarding the excitation module, the following aspects need to be explained: 1. Advantages of using capacitors for excitation In the present invention, the rotor of the three-phase asynchronous motor usually has residual magnetism. During the rotation of the rotor, the stator coil generates an induced current to charge the first capacitor C1, the second capacitor C2, and the third capacitor C3. The voltage across the three capacitors lags the current by 90°. The three capacitors discharge through the stator coil to provide excitation current, and the motor enters the power generation state.

[0077] In this embodiment, by means of capacitor excitation, automatic control of charging / discharging can be achieved, other interventions can be reduced, and reliable starting of the elevator power generation and braking intelligent device can be ensured.

[0078] 2. The capacitance values ​​of the first capacitor, the second capacitor, and the third capacitor are the same or different In this embodiment, the capacitance values ​​of the first capacitor, the second capacitor, and the third capacitor are the same, which can ensure that the three-phase output power of the three-phase asynchronous motor is the same when in the generating state, thereby increasing the reliability of the entire circuit.

[0079] The present invention is not limited to this embodiment. In other embodiments of the present invention, the capacitance values ​​of the first capacitor, the second capacitor, and the third capacitor may also be different, and the excitation current can also be provided for the three-phase asynchronous motor, and the present invention can also be implemented, and it is also within the protection scope of the present invention.

[0080] In this embodiment, capacitors are arranged between the Ath terminal and the Bth terminal, between the Bth terminal and the Cth terminal, and between the Cth terminal and the Ath terminal of the three-phase asynchronous motor, but the present invention is not limited thereto. In other embodiments of the present invention, capacitors may be arranged in only one or two of the above three positions, as long as the excitation effect can be achieved and the three-phase asynchronous motor enters the power generation state, which is also within the protection scope of the present invention.

[0081] 3. Capacitance formulas for the first capacitor, the second capacitor, and the third capacitor It should be noted that the above calculation of the capacitance value is only a theoretical value. In actual situations, the capacitance value needs to be adjusted according to the actual scene and effect to achieve the best excitation effect.

[0082] In the present invention, the power load module is used to form a power load outside the three-phase asynchronous motor, consume the electric energy generated by the three-phase asynchronous motor when it loses control, and generate a braking torque. The power load module includes: M impedance elements, wherein at least two of the three positions between two terminals of the three-phase asynchronous motor form a power load by one or more of the M impedance elements, M≥3.

[0083] like Figure 2 As shown, the elevator power generation brake intelligent device of this embodiment further includes: a load switch group, the load switch group includes: a first load switch K1 and a second load switch K2. The first impedance K1 and the second load switch K2 are controlled by the main control circuit, and both are relays.

[0084] The power load module includes: a first resistor R1, a second resistor R2, and a third resistor R3, wherein: ① The first resistor R1 and the third resistor R3 are connected between the A terminal and the B terminal of the three-phase asynchronous motor through the first load switch K1; ② The third resistor R3 and the second resistor R2 are connected between the B terminal and the C terminal of the three-phase asynchronous motor through the second load switch K2; ③ The second resistor R2 and the first resistor R1 are connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor through the first load switch K1 and the second load switch K2.

[0085] Among them, the resistance values ​​R of the first resistor, the second resistor, and the third resistor satisfy: , the unit of resistance value R is ohm, is the rated voltage of the three-phase asynchronous motor, It is the input power of the elevator motor when the elevator is unloaded.

[0086] The first load switch K1 and the second load switch K2 are relays controlled by the main control circuit. The main control circuit is also used for: ① When the elevator is detected to be out of control, the first load switch and the second load switch are set to a closed state; ② When it is detected that the speed of the three-phase asynchronous motor drops to a preset first speed lower limit, at least one of the first load switch and the second load switch is in an off state; Among them, the first speed lower limit value is n down-1 Satisfy: n down-1 ≤0.8n0, where n0 is the rated speed of the three-phase asynchronous motor.

[0087] In this embodiment, when the elevator power generation brake intelligent device enters the power generation state, when the magnetic encoder detects that the rotor speed is close to the rated speed, the main control electronic control relays K1 and K2 are energized, and three load resistors - R1, R2, and R3 are connected to start consuming the electric energy output by the three-phase asynchronous motor to generate a braking torque. Further, when it is found that the speed of the three-phase asynchronous motor drops to 80%, in order to avoid the power generation state collapse due to too low speed, K1 and K2 are disconnected or disconnected at the same time according to the speed drop, so as to change the load condition, adjust the braking torque, and realize continuously adjustable power consumption control, thereby more accurately controlling the braking torque.

[0088] It should be noted that the present embodiment sets a free combination of R1 to R3 instead of calculating a fixed resistance value according to the main power of the three-phase asynchronous motor. This can be explained from two aspects: (1) Adapt to different car weights When a fault occurs, there is no way to determine how many passengers are in the car, that is, if there are fewer passengers in the car, the mass difference between the counterweight and the car will be larger, so the energy it generates will be more, and more energy will need to be consumed. If there are slightly more passengers in the car, it is closer to the final mass, then the mass it provides will be less, the electricity generated will be less, and the electricity required will be less. Therefore, this embodiment can adapt to the energy consumption under different car weights by setting the free combination of R1~R3, which is more flexible.

[0089] (2) Avoid the collapse of the power generation state of the three-phase asynchronous motor The present invention allows the motor to enter an asynchronous power generation state, and sets an electric load on the outside to consume the generated electric energy, generating a braking resistance in the process of consumption.

[0090] The reason for designing two relays and resistors is that the present invention connects different resistors in series in the coil. It is found through experiments that when the actual speed of the motor is lower than 80% of the rated speed, or the power consumption reaches or exceeds 80% of the rated load of the motor, the power generation state of the three-phase asynchronous motor will collapse.

[0091] After the three-phase asynchronous motor power generation collapses, it will stop generating electricity and the elevator will enter an out-of-control state. Therefore, it is necessary to control the load of the three-phase asynchronous motor to ensure that the output power does not exceed 80% of the rated load of the motor, and the actual speed of the rotor is always limited to between 80% and 110% of the rated speed. For this purpose, if the rotor speed is high, a resistor is inserted to pull the rotor speed down; if the speed is low, a resistor is removed to accelerate the rotor, so that the three-phase asynchronous motor is always in a generating state until any end of the car or the counterweight reaches the buffer, the movement stops, and the rotor of the three-phase asynchronous motor also stops.

[0092] Regarding the power load module, the following aspects need special explanation: 1. Resistance values ​​of the first resistor R1, the second resistor R2, and the third resistor R3 The resistance values ​​of the first resistor R1 , the second resistor R2 , and the third resistor R3 are the same or different.

[0093] In this embodiment, the resistance values ​​of the first resistor R1, the second resistor R2, and the third resistor R3 are the same, which can ensure that the loads of the three phases are the same, the braking torque is the same, and the elevator braking is more balanced and stable.

[0094] It should be particularly noted that the present invention can also be implemented when the resistance values ​​of the first resistor R1 , the second resistor R2 , and the third resistor R3 are different.

[0095] 2. Number of power loads In this embodiment, when the switches of the access switch group and the load switch group are in a closed state, there are resistors between the Ath terminal and the Bth terminal; between the Bth terminal and the Cth terminal; and between the Cth terminal and the Ath terminal of the three-phase asynchronous motor, and power consumption can be achieved, but the present invention is not limited to this.

[0096] In some other embodiments of the present invention, a resistor may be set at one or two of the three positions to achieve power consumption, which can also implement the present invention and is also within the protection scope of the present invention.

[0097] 3. Access method of power load In this embodiment, the load condition is adjusted by the first load switch K1 and the second load switch K2, thereby realizing continuously adjustable power consumption control, thereby more accurately controlling the braking torque, but the present invention is not limited thereto. In other embodiments of the present invention, the load switch may not be provided, and only a load resistor may be provided between the two terminals. Although the accuracy is poor, the present invention can also be implemented and is also within the protection scope of the present invention.

[0098] 4. Implementation of load switch In this embodiment, the first load switch K1 and the second load switch K2 are relays controlled by a main control circuit.

[0099] The present invention is not limited to this embodiment. In other embodiments of the present invention, K1 and K2 may also be replaced by other switching elements such as transistor choppers.

[0100] The applicant previously proposed an elevator and a control method thereof (patent application number: CN202311099173.9). The elevator includes: a car; a traction machine connected to the car; a drive system including a motor that drives the rotation of the traction machine through a transmission shaft; a monitoring system for monitoring the rotation speed of the transmission shaft and the AC power supply current of the motor; and a speed control system that controls the drive system to reduce the rotation speed when the AC power supply current is lower than a predetermined first current threshold and the rotation speed is higher than a predetermined speed threshold. The speed control system includes: a DC power supply connected in series with the motor; an insulated gate bipolar transistor IGBT connected in series with the DC power supply; and a controller that controls the DC power supply current of the DC power supply when the AC power supply current is lower than a predetermined first current threshold and the rotation speed is higher than a predetermined speed threshold.

[0101] Compared with the braking method of the above-mentioned prior art, the intelligent device for elevator dynamic braking in this embodiment has the following advantages: ① DC braking requires continuous power supply, and continuous braking cannot be achieved without power supply, while dynamic braking can be achieved by self-excitation power generation of the motor, and has a weaker reliance on power supply. When necessary, the main control circuit power supply can rely on the asynchronous motor power supply; ② DC braking requires a large braking current at rated speed or even overspeed. In many cases, such power supply may not be available, while asynchronous dynamic braking can generate braking torque with extremely low power supply. After the power generation state is established, the device itself can be powered by the electric energy generated by the asynchronous motor, thus getting rid of the dependence on external power supply.

[0102] As mentioned above, there is usually residual magnetism in the rotor of a three-phase asynchronous motor, which can automatically enable the motor to enter the asynchronous power generation state. However, in some cases, the rotor residual magnetism is not enough to enable the motor to enter the asynchronous power generation state. When the motor speed reaches 60% of the rated speed, the three-phase asynchronous motor still does not automatically enter the power generation state. At this time, the asynchronous power generation start auxiliary module is required to excite the three-phase asynchronous motor to generate electricity.

[0103] In a typical scenario, the rotor of the three-phase asynchronous motor is just at the zero-crossing point of the three-phase alternating current at the moment of power failure. There is no residual magnetism in the rotor, which means that the motor will not generate electricity, and the three-phase asynchronous motor cannot establish an asynchronous power generation state. Or because of a long period of time, the residual magnetism in the rotor disappears. In these cases, the asynchronous power generation starting auxiliary module in the present invention uses a DC power supply to pass a pulse of a cycle close to the rotor rotation speed into the three-phase asynchronous motor to magnetize the rotor. After magnetization, the three-phase asynchronous motor can enter a power generation state, ensuring the smooth start of the power generation state.

[0104] Specifically, the elevator dynamic braking intelligent device of this embodiment also includes: an asynchronous power generation start auxiliary module, which is used to output an excitation pulse to the three-phase asynchronous motor. The access switch group is connected between the asynchronous power generation start auxiliary module and any two of the three-phase terminals of the three-phase asynchronous motor. The main control circuit is used to: when it is detected that the speed of the three-phase asynchronous motor is lower than the preset second speed lower limit, output an excitation pulse to the three-phase asynchronous motor through the asynchronous power generation start auxiliary module to make the motor speed higher than the second speed lower limit; wherein the second speed lower limit is between 50% and 90% of the rated speed of the three-phase asynchronous motor. In this embodiment, the second speed lower limit is set to 70% of the rated speed of the three-phase asynchronous motor.

[0105] Please refer to Figure 2 In this embodiment, the asynchronous generator starting auxiliary module includes: a DC power supply, whose negative output end is connected to the Cth terminal of the three-phase asynchronous motor; a switch component, whose first end is connected to the positive output end of the DC power supply; a diode, whose negative end is connected to the second end of the switch component, and whose positive end is connected to the Ath terminal of the three-phase asynchronous motor.

[0106] Preferably, in this embodiment, the output voltage of the DC power supply is between 10V and 36V. Since the rotor coil impedance is very low, the voltage of the asynchronous generator start-up auxiliary module is preferably lower than 36V. Preferably, the current that the asynchronous generator start-up auxiliary module can provide is 10V 30A or 50A. In addition, the frequency of the excitation pulse f Meet: 0.5kHz≤ f ≤5kHz; the switching component is an insulated gate bipolar transistor IGBT.

[0107] Regarding the asynchronous generator starting auxiliary module, the following aspects need to be explained: 1. The asynchronous generator start-up auxiliary module can be set up In this embodiment, in order to smoothly start the three-phase asynchronous motor in the generating state, an asynchronous generating start auxiliary module is provided, but the present invention is not limited thereto. In some other embodiments of the present invention, the asynchronous generating start auxiliary module may not be provided, and the present invention can also be implemented, because the three-phase asynchronous motor may not be able to enter the generating state only in special circumstances.

[0108] 2. Setting location of asynchronous generator starting auxiliary module In this embodiment, the asynchronous generator starting auxiliary module is disposed between the Ath terminal and the Cth terminal of the three-phase asynchronous motor, but the present invention is not limited thereto.

[0109] In other embodiments of the present invention, the asynchronous power generation starting auxiliary module can also be set in other positions, for example: between the B and C terminals; or, between the A and B terminals; or, the asynchronous power generation starting auxiliary module can be set in 2 or 3 of the above positions at the same time, which can also realize the present invention and is also within the protection scope of the present invention.

[0110] 3. Implementation of asynchronous generator start-up auxiliary module In this embodiment, the excitation pulse is realized by a DC power supply and a switch component, thereby realizing power generation start-up assistance, but the present invention is not limited thereto. In other embodiments of the present invention, the excitation pulse can also be realized by directly using a pulse power supply, which can also realize the present invention and is also within the protection scope of the present invention.

[0111] After introducing the various modules of this embodiment, the following is an overall introduction to the working conditions of this embodiment: the main control circuit detects the unexpected movement of the elevator motor through the magnetic encoder and the monitoring of the voltage transmitter output. When the unexpected movement is detected, the power generation state of the three-phase asynchronous motor is monitored through the voltage transmitter. Usually, the motor rotor will have residual magnetism. During the rotation of the rotor, the stator coil generates an induced current to charge C1, C2, and C3. The voltage across the capacitor lags the current by 90°. The capacitor discharges through the stator coil to provide excitation current, and the motor enters the power generation state. If the residual magnetism of the motor rotor is not enough to make the motor enter the synchronous power generation state, the motor When the motor speed reaches 70% of the rated speed, the main control circuit controls the IGBT to turn on and off and provide pulses slightly lower than the motor speed to the two phases of the motor to assist in entering the power generation state. When the voltage transmitter detects that the speed is close to the rated speed, it controls relays K1 and K2 to energize, connects to the load resistor, and begins to consume the electric energy output by the motor to generate braking torque. When the motor speed drops to 80%, in order to avoid the power generation state collapse due to too low speed, choose to disconnect K1, K2 or disconnect K1 and K2 at the same time according to the speed drop to change the load condition and adjust the braking torque until the elevator car or counterweight is pressed firmly on the buffer.

[0112] So far, the introduction of the intelligent elevator dynamic braking device according to the first embodiment of the present invention has been completed.

[0113] The second embodiment of the present invention provides an intelligent device for elevator dynamic braking. Figure 4 FIG. 2 is a schematic diagram of the structure of an intelligent elevator braking device according to a second embodiment of the present invention. Figure 4 As shown, the elevator power generation brake intelligent device of this embodiment is similar to the first embodiment, except that the capacitor in the excitation module adopts a star connection. The excitation module is described in detail below.

[0114] Figure 5 for Figure 4 The diagram shows the star connection of capacitors in the intelligent elevator braking device. Figure 4 and Figure 5 As shown, in this embodiment, the excitation module includes: a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7, wherein: the fifth capacitor C5 and the sixth capacitor C6 are both connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor; the sixth capacitor C6 and the seventh capacitor C7 are both connected between the Bth terminal and the Cth terminal of the three-phase asynchronous motor; the seventh capacitor C7 and the fifth capacitor C5 are both connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor; wherein the capacitance values ​​of the fifth capacitor, the sixth capacitor, and the seventh capacitor are the same or different.

[0115] In this embodiment, the capacitance values ​​C of the fifth capacitor, the sixth capacitor, and the seventh capacitor satisfy:

[0116] in, They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively. S is the coefficient, 500≤S≤3000.

[0117] Preferably, 1000≤S≤2000. Most preferably, 1800≤S≤2000.

[0118] In the configuration of the excitation module of this embodiment, two capacitors are used to perform the excitation work of charging and discharging. This has the advantages of lower requirements on the capacitor's voltage resistance and smaller size.

[0119] It can be seen from this embodiment and the first embodiment that there are many ways to implement the excitation module through capacitors in the present invention. Those skilled in the art can know how to implement these ways, which will not be described in detail here.

[0120] The third embodiment of the present invention provides an intelligent device for elevator dynamic braking. Figure 6 This is a schematic diagram of the structure of the intelligent device for elevator power generation and braking according to the third embodiment of the present invention. Figure 6As shown, this embodiment is similar to the first embodiment, and the difference lies in the setting mode of the resistor in the power load module.

[0121] In this embodiment, the power load module includes: a full-wave rectifier circuit composed of 6 diodes; a chopper, a chopper control module, and a load resistor R4. In the power load module of the intelligent device for generating and braking elevators in this embodiment, the full-wave rectifier circuit rectifies the three-phase AC power into DC power, and the DC power is connected to the load resistor R4 through the chopper. The load current is continuously adjusted by adjusting the chopper voltage of the chopper, thereby achieving the effect of controlling the braking torque. In this embodiment, the chopper switch element is an IGBT element.

[0122] In this embodiment, the chopper is controlled by a chopper control module. When the chopper control module detects that the DC bus voltage is higher than the set value, the chopper control module controls the IGBT to connect the load resistor R4 to the loop through pulse width modulation at a frequency of 4kHz to 7kHz to control the current in the load resistor. The load resistor R4 consumes electrical energy in the DC loop and generates a braking torque. When the DC bus voltage is lower than the set value, the IGBT is turned off, the DC loop is not formed, and there is no consumption of electrical energy, thereby preventing power generation collapse. Among them, the set value is generally set to 50%~90% of the DC bus voltage.

[0123] The second aspect of the present invention provides an elevator. The fourth embodiment of the present invention provides an elevator. Figure 1 and Figure 2 The elevator of this embodiment includes: a car; a traction wheel driven by a three-phase asynchronous motor; a traction rope, the middle of which is wound around the traction wheel, and the first end is connected to the car; the second end is connected to the counterweight device; the intelligent device for elevator power generation and braking of the first embodiment; an upper buffer and a lower buffer, which are respectively arranged at the upper end and the lower end of the elevator shaft. When it is detected that the elevator is in an out-of-control state, the three-phase asynchronous motor enters the power generation state, and the power load module is used as the output load to consume the electric energy output by the three-phase asynchronous motor, generate a braking torque, and slow down the movement speed of the elevator car.

[0124] Those skilled in the art should understand that the elevator dynamic braking intelligent device in this embodiment can also adopt the elevator dynamic braking intelligent device in the second to fourth embodiments, which can also implement the present invention and is also within the protection scope of the present invention.

[0125] So far, the various embodiments of the present invention have been introduced. According to the above description, those skilled in the art should have a clear understanding of the present invention.

[0126] It should be noted that, unless explicitly indicated to the contrary, the numerical parameters in the specification and claims of the present invention may be approximate values ​​and may be changed according to the content of the present invention. Specifically, all the numbers recorded in the specification and claims indicating the content of the composition, reaction conditions, etc., should be understood to be modified by the term "about" in all cases, and the meaning of the expression is to include a change of ±10% from a specific number in some embodiments.

[0127] The ordinal numbers used in the specification and claims, such as "first", "second", "third", "primary", "secondary", as well as Arabic numerals, letters, etc., to modify the corresponding elements (or steps), are intended only to clearly distinguish an element (or step) with a certain name from another element (or step) with the same name, and do not mean that the element (or step) has any ordinal number, nor do they represent the order of one element (or step) and another element (or step).

[0128] The present invention may also be implemented as a device or apparatus program (e.g., a computer program and a computer program product) for performing part or all of the methods described herein. Such a program implementing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0129] The present invention can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. The various component embodiments of the present invention can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. The physical implementation of the hardware structure includes but is not limited to physical devices, which include but are not limited to transistors, memristors, DNA computers, single-chip microcomputers, microprocessors or digital signal processors (DSPs). In addition, the present invention is not directed to any specific programming language. It should be understood that the content of the present invention can be implemented using various programming languages, and the description of specific languages ​​herein is intended to disclose the best implementation of the present invention.

[0130] Those skilled in the art should understand that in the claims and the specification of the present invention, the word "comprising" does not exclude the existence of elements not listed in the claims. The word "a" or "an" preceding an element does not exclude the existence of a plurality of such elements. For certain implementations, if they are not the key content of the present invention and are well known to those of ordinary skill in the art, they are not described in detail in the drawings or the text of the specification due to space limitations. In this case, reference can be made to the relevant prior art for understanding.

[0131] Furthermore, the above embodiments are provided merely to enable the present invention to satisfy legal requirements, and the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0132] Similarly, it should be understood that in order to simplify the present invention, in the above description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the invention should not be interpreted as reflecting the following intention: the claimed invention requires more features than the features explicitly stated in each claim. More specifically, as reflected in the claims, each inventive aspect lies in less than all the features of the previous single embodiment. Moreover, the embodiments can be mixed and matched with each other or with other embodiments based on design and reliability considerations, that is, the technical features in different embodiments can be freely combined to form more embodiments. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present invention.

[0133] The above specific embodiments provide a detailed description of the objectives, technical means and beneficial effects of the present invention. It should be understood that the purpose of the detailed description is to enable those skilled in the art to understand the present invention more clearly, and it is not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An intelligent elevator power generation braking device, characterized in that: include: Excitation module and electrical load module; Status monitoring module, used to monitor the operating status of the elevator; A switch group is connected between the excitation module, the power load module and the three-phase terminals of the three-phase asynchronous motor; The main control circuit is used to control the access switch group to connect the excitation module and the power load module to the three-phase asynchronous motor when the elevator is detected to be out of control, wherein: The excitation module provides excitation current for the three-phase asynchronous motor; The rotor of the three-phase asynchronous motor rotates due to the elevator losing control, and the three-phase asynchronous motor enters a power generation state and outputs electric energy to the outside; The electric load module consumes the electric energy, thereby generating a braking torque for the out-of-control elevator.

2. The intelligent elevator power generation braking device according to claim 1 is characterized in that: The excitation module includes: N capacitors, N≥2; Among them, an energy storage and discharge excitation unit is formed by one or more of the N capacitors between two terminals of the three-phase terminals of the three-phase asynchronous motor.

3. The intelligent elevator braking device according to claim 2 is characterized in that: The excitation module includes: a first capacitor, a second capacitor, and a third capacitor, wherein: A first capacitor is connected between the A terminal and the B terminal of the three-phase asynchronous motor; A second capacitor is connected between the B terminal and the C terminal of the three-phase asynchronous motor; A third capacitor is connected between the A terminal and the C terminal of the three-phase asynchronous motor; The capacitance values ​​of the first capacitor, the second capacitor and the third capacitor are the same or different.

4. The intelligent elevator power generation and braking device according to claim 3 is characterized in that: The three-phase asynchronous motor is an industrial frequency motor, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor satisfy: , where the unit of capacitance C is μF, They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively, K is the coefficient, 500≤K≤10000; or The three-phase asynchronous motor is a non-industrial frequency motor, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor satisfy: , where: the unit of capacitance C is μF, They are the rated current, rated voltage and rated frequency of the three-phase asynchronous motor respectively. Q is the coefficient, 0.1≤Q≤1.

5. The intelligent elevator power generation braking device according to claim 4 is characterized in that: The withstand voltage of the first capacitor, the second capacitor and the third capacitor is not less than 110% of the rated voltage of the three-phase asynchronous motor; And / or, the three-phase asynchronous motor is an industrial frequency motor, whose operating frequency is 50 Hz, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, 3000≤K≤3500; or, the three-phase asynchronous motor is a non-industrial frequency motor, and the capacitance values ​​C of the first capacitor, the second capacitor, and the third capacitor are the same, 0.2≤Q≤0.

4.

6. The intelligent elevator power generation braking device according to claim 2 is characterized in that: The excitation module includes: a fifth capacitor, a sixth capacitor, and a seventh capacitor, wherein: A fifth capacitor and a sixth capacitor, both of which are connected between the A terminal and the B terminal of the three-phase asynchronous motor; A sixth capacitor and a seventh capacitor, both of which are connected between the B terminal and the C terminal of the three-phase asynchronous motor; The seventh capacitor and the fifth capacitor are connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor; The capacitance values ​​of the fifth capacitor, the sixth capacitor and the seventh capacitor are the same or different.

7. The intelligent elevator power generation and braking device according to claim 6, characterized in that: The capacitance values ​​C of the fifth capacitor, the sixth capacitor and the seventh capacitor satisfy: ， in, They are the rated current, rated voltage and power factor of the three-phase asynchronous motor respectively. S is the coefficient, 500≤S≤3000.

8. The intelligent elevator power generation braking device according to claim 1 is characterized in that: The power load module comprises: M impedance elements, M≥1; In which, at least one of the three positions between two terminals of the three-phase asynchronous motor is provided with an electric load formed by one or more of the M impedance elements.

9. The intelligent elevator dynamic braking device according to claim 8, characterized in that: Also included: a load switch group, the load switch group including: a first load switch and a second load switch; The power load module comprises: a first resistor, a second resistor, and a third resistor, wherein: A first resistor and a third resistor, both of which are connected between the Ath terminal and the Bth terminal of the three-phase asynchronous motor through a first load switch; A third resistor and a second resistor, both of which are connected between the B terminal and the C terminal of the three-phase asynchronous motor through a second load switch; The second resistor and the first resistor are connected between the Cth terminal and the Ath terminal of the three-phase asynchronous motor through the first load switch and the second load switch.

10. The intelligent elevator power generation braking device according to claim 9, characterized in that: The main control circuit is also used for: When an out-of-control state of the elevator is detected, the first load switch and the second load switch are set to a closed state; When it is detected that the speed of the three-phase asynchronous motor drops to a preset first speed lower limit, at least one of the first load switch and the second load switch is in an off state; Among them, the first speed lower limit value is n down-1 Satisfy: n down-1 ≤0.8n0, where n0 is the rated speed of the three-phase asynchronous motor.

11. The intelligent elevator power generation braking device according to claim 9, characterized in that: The first load switch and the second load switch are: relays or transistor choppers; And / or, the resistance values ​​of the first resistor, the second resistor and the third resistor are the same or different; And / or, the resistance values ​​R of the first resistor, the second resistor and the third resistor satisfy: ， The unit of resistance value R is ohm. is the rated voltage of the three-phase asynchronous motor, It is the input power of the elevator's downward motor when the elevator is unloaded, 0.5≤T≤2.

12. The intelligent elevator power generation braking device according to claim 11, characterized in that: The resistance values ​​of the first resistor, the second resistor and the third resistor are the same; The resistance values ​​R of the first resistor, the second resistor, and the third resistor satisfy: .

13. The intelligent elevator power generation braking device according to claim 8, characterized in that: The power load module includes: a full-wave rectifier circuit; a chopper, a chopper control module, and a load resistor; Among them, the full-wave rectifier circuit fully rectifies the three-phase AC power into DC power, and the DC power is connected to the load resistor through the chopper. The load current is continuously adjusted by adjusting the chopping voltage of the chopper, thereby controlling the braking torque.

14. The intelligent elevator power generation braking device according to claim 1, characterized in that: It also includes: an asynchronous generator start-up auxiliary module, which is used to output excitation pulses to the three-phase asynchronous motor; The access switch group is connected between the asynchronous generator start-up auxiliary module and any two of the three-phase terminals of the three-phase asynchronous motor; The main control circuit is used for: When it is detected that the speed of the three-phase asynchronous motor is higher than the preset second speed lower limit, if no output voltage is detected from the three-phase asynchronous motor, the main control circuit outputs an excitation pulse to the three-phase asynchronous motor through the asynchronous power generation starting auxiliary module to make the motor enter an asynchronous power generation state; Wherein, the second speed lower limit is between 50% and 90% of the rated speed of the three-phase asynchronous motor.

15. The intelligent elevator power generation braking device according to claim 14, characterized in that: The asynchronous generator starting auxiliary module comprises: A DC power supply, the negative output terminal of which is connected to one of the three terminals of the three-phase asynchronous motor; A switch component has a first end connected to the positive output terminal of the DC power supply and a second end connected to another one of the three terminals of the three-phase asynchronous motor.

16. The intelligent elevator power generation braking device according to claim 15, characterized in that: The asynchronous generator start-up auxiliary module further includes: a diode, a cathode end of which is connected to the second end of the switch component, and a positive end of which is connected to another one of the three terminals of the three-phase asynchronous motor; and / or, the frequency of the excitation pulse f Meet: 0.5kHz≤ f ≤5kHz; And / or, the output voltage of the DC power supply is between 10V and 36V; And / or, the switch component is an insulated gate bipolar transistor IGBT.

17. The intelligent elevator power generation braking device according to claim 1, characterized in that: The state monitoring module is used to monitor the active power input and rotor rotation in the elevator; The main control circuit is used to determine that the elevator is in an out-of-control state when the following conditions are met: the three-phase asynchronous motor rotates without active power input; and the following control logic is executed according to the judgment result: When the elevator is not out of control, the excitation module and the power load module are kept isolated from the connection terminals connecting the three-phase asynchronous motor and the elevator control cabinet; When the elevator is detected to be out of control, the control access switch group connects the excitation module and the power load module in parallel to the connection terminals of the three-phase asynchronous motor and the elevator control cabinet.

18. The intelligent elevator dynamic braking device according to claim 17, characterized in that: The status monitoring module comprises: A motor power monitoring module is used to monitor the power voltage input to the three-phase asynchronous motor; The motor rotation monitoring module is used to monitor the rotation of the rotor in a three-phase asynchronous motor.

19. The intelligent elevator dynamic braking device according to claim 18, characterized in that: The motor rotation monitoring module is: a magnetic encoder, which is arranged at the shaft end of the three-phase asynchronous motor, the shaft end is connected to the rotor, and its sampling period T satisfies: T≤20ms; And / or, the motor current detection module is a voltage transmitter.

20. A traction drive elevator, characterized in that: include: Car; The traction sheave is driven by a three-phase asynchronous motor; A traction rope, the middle of which is wound around the traction wheel, with a first end connected to the car and a second end connected to the counterweight device; The intelligent device for elevator power generation braking according to any one of claims 1 to 19; The upper buffer and the lower buffer are respectively arranged at the upper end and the lower end of the elevator shaft; Among them, when it is monitored that the elevator is in an out-of-control state, the three-phase asynchronous motor enters the power generation state, and the power load module serves as the output load, consuming the electric energy output by the three-phase asynchronous motor, generating braking torque, and slowing down the movement speed of the elevator car.

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