Wind power tower tube elevator control system

Abstract

The invention belongs to the field of electrical control, and relates to a wind power tower tube elevator control system which comprises a three-phase motor driving assembly and a circuit formed by electrically connecting a three-phase alternating voltage, a zero-cross detection circuit, a controller, a grid driving circuit, a three-phase six-arm topological structure and a three-phase motor in sequence. The input of the three-phase six-arm topological structure comprises a three-phase alternating current voltage; the zero-cross detection circuit comprises an optocoupler, the primary side of the optocoupler is connected with the input of a certain phase, the secondary side of the optocoupler is connected to a pin of the controller, the on-off of the optocoupler is changed when a voltage zero-cross point is accessed, the pin generates a zero-cross signal, and the controller outputs a corresponding PWM signal according to the zero-cross signal of the pin to trigger an upper arm and a lower arm of the gate drive circuit to drive. And the three-phase six-arm topological structure performs output based on the three-phase AC voltage and the trigger gate drive circuit, and controls the phase and speed of the three-phase motor.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electrical control, and in particular relates to a wind power tower drum elevator control system. BACKGROUND

[0002] The wind power tower drum elevator is used in the wind power tower drum, and provides a passage for ascending or descending along the wind power tower drum by controlling the opening and closing of the cover plate. In the field of industrial automation, especially mechanical equipment such as elevators that need three-phase motor driving, there are very high requirements for the reliability, environmental adaptability and cost control of the control system.

[0003] In the daily operation of the existing tower drum elevator, obvious shaking problems often occur during the start and stop stage - the core reason is that in the conventional design, the motor power supply relies on the relay to directly cut into the mains: as soon as the relay is turned on, the motor is instantly connected to the rated voltage from a completely stationary state, and directly rises to the rated speed; when stopping, the voltage is suddenly cut off, and the speed drops sharply. This "quick start and quick stop" will make the passengers feel obvious jolting, not only affecting the riding experience, but also possibly exacerbating the wear and tear of mechanical parts in the long run.

[0004] To solve this problem, the conventional solution in the industry is to install a frequency converter on the elevator, and use the "soft start" function of the frequency converter to gradually increase the motor speed from slow to fast to the rated value, and the shaking during start and stop will be greatly alleviated. However, the disadvantages of the frequency converter are very prominent: high cost, which will significantly increase the overall manufacturing cost of the elevator, especially for batch application scenarios, the economic pressure is greater.

[0005] For temperature management, the existing technology uses a single mechanical temperature control switch or a simple digital temperature control IC. When the temperature is lower than the set point (such as 0°C), heating is started, and when the temperature is higher than the set point, heating is stopped. This two-point control will cause the heating element and the relay to start and stop frequently at the critical temperature point, shortening the service life of the equipment. When the temperature fluctuates near the set point, the system will constantly switch between the start and stop states, and the control is unstable. Programmable logic controllers (PLCs) or advanced temperature control modules can also be used to achieve complex control logic with temperature sensors. Although the performance is stable, the cost is high, which is too expensive for cost-sensitive applications.

[0006] For signal detection, the existing technology usually uses a discrete modular design, that is, temperature control, motor drive, I / O acquisition, power supply and other functions are realized by multiple independent modules or boards, and then connected into a system through cables, so that multiple modules result in a large number of wiring, increase the fault points, the total cost of multiple independent modules is usually higher than that of highly integrated single boards, and the communication between modules may introduce delay, and the connectors and cables are the weak links of system reliability. SUMMARY

[0007] The present application is proposed based on the above needs of the prior art, and aims to provide a wind power tower drum elevator control system to improve the working performance.

[0008] To solve the above problems, the technical scheme provided by the present application includes:

[0009] The wind power tower drum elevator control system includes a three-phase motor driving assembly, a temperature adjusting assembly, and a safety protection and state detection assembly. The three-phase motor driving assembly includes a circuit formed by a three-phase alternating voltage, a zero-crossing detection circuit, a controller, a gate drive circuit, a three-phase six-arm topology structure, and a three-phase motor connected in sequence, and the input of the three-phase six-arm topology structure further includes a three-phase alternating voltage. The zero-crossing detection circuit includes an optical coupler, the primary side of the optical coupler is connected to the input of a certain phase, and the secondary side of the optical coupler is connected to a pin of the controller. When the voltage passes through a zero point, the on-off of the optical coupler is changed, which causes a zero-crossing signal to be generated at the corresponding pin. The controller outputs a corresponding PWM signal according to the zero-crossing signal obtained by the pin, and triggers the upper arm drive and the lower arm drive of the gate drive circuit. The three-phase six-arm topology structure outputs based on the three-phase alternating voltage and the triggered gate drive circuit, and controls the phase and speed of the three-phase motor. The temperature adjusting assembly includes a first temperature switch, a second temperature switch, a solid-state relay, and a heating sheet. When the temperature is lower than a preset low temperature, the first circuit is turned on, and the heating sheet starts to heat. When the temperature is higher than the preset low temperature and lower than a preset high temperature, the second circuit is turned on, the solid-state relay is in a self-locking stage, and the heating sheet continues to heat. When the temperature is higher than the preset high temperature, the self-locking temperature maintaining state is released, and the above heating process is repeated until the temperature decreases to be lower than the preset low temperature. The safety protection and state detection assembly includes a software logic and state management part that processes signals output by a signal acquisition and anti-interference processing part, triggers a protection action execution part to implement corresponding actions to achieve safety protection.

[0010] Preferably, the temperature adjusting assembly includes that one end of the first temperature switch is directly connected to a working power input end VCCP, and the other end is connected to one end of the heating sheet and a pin 1 of the solid-state relay coil. One end of the second temperature switch is connected to a pin 2 of the solid-state relay coil, and the other end is connected to a power ground interface GND2. The common end COM of the solid-state relay is directly connected to the VCCP interface, and the normally open end NO is connected to one end of the heating sheet and merges with the connection point of the first temperature switch and the coil pin 1.

[0011] Preferably, when the temperature is lower than the preset low temperature, the first circuit is turned on, including that the current flows through the working power input end VCCP, the closed first temperature switch, the heating sheet, the pin 1 of the solid-state relay coil, the pin 2 of the solid-state relay coil, the closed second temperature switch, and the ground interface in sequence, and the following actions are correspondingly generated: the solid-state relay coil is energized and attracted, the common end COM and the normally open end NO of the solid-state relay are connected, and the heating sheet starts to heat.

[0012] Preferably, when the temperature is higher than the preset low temperature and lower than the preset high temperature, the second circuit is turned on, the solid state relay is in the self-locking stage, and the current flows through the working power input terminal VCCP, the solid state relay common terminal COM, the solid state relay normally open terminal NO, the heating sheet, the pin 1 of the solid state relay coil, the pin 2 of the solid state relay coil, the second temperature switch and the ground interface in turn, and the following actions are generated accordingly: the first temperature switch is turned off, the solid state relay coil continues to obtain the current through the normally open contact of the solid state relay, the heating sheet generates heat.

[0013] Preferably, when the temperature is higher than the preset high temperature, the self-locking and heat preservation state is released, the first circuit and / or the second circuit are cut off by the disconnection of the second temperature switch, the solid state relay coil is released, the common terminal of the solid state relay is disconnected with the normally open terminal, the heating sheet completely stops working, and the self-locking state is released.

[0014] Preferably, the zero-crossing detection circuit comprises zero-crossing detection of a positive half cycle and zero-crossing detection of a negative half cycle; the zero-crossing detection of the positive half cycle comprises a first optocoupler, a certain phase of three-phase alternating voltage is connected to the cathode of the original side of the first optocoupler, the zero line is connected to the anode of the original side of the first optocoupler, the collector of the secondary side of the first optocoupler is connected to the pin of the controller, and the emitter is grounded; the zero-crossing detection of the negative half cycle comprises a second optocoupler, a certain phase of three-phase alternating voltage is connected to the cathode of the original side of the second optocoupler, the zero line is connected to the anode of the original side of the second optocoupler, the collector of the secondary side of the first optocoupler is connected to the pin of the controller, and the emitter is grounded.

[0015] Preferably, the signal acquisition and anti-interference processing part comprises a three-stage anti-interference input circuit, the first stage is magnetic ring suppression, the second stage is RC attenuation, and the third stage is a voltage comparator; when the signal passes through the three-stage anti-interference input circuit, it passes through the magnetic ring in the first stage, the low-pass filter composed of the resistor and the capacitor in the second stage and the voltage comparator composed of the operational amplifier in the third stage in turn.

[0016] Preferably, the third stage comprises a third optocoupler, the anode of the original side of the third optocoupler is connected to the output of the operational amplifier through a current limiting resistor, the cathode of the original side of the third optocoupler is connected to the ground interface, the collector of the secondary side of the third optocoupler is connected to the +3.3V power supply, and the emitter is connected to the controller.

[0017] Preferably, the anode of the input terminal of the operational amplifier is connected to the signal filtered by the first stage and the second stage, and the cathode of the input terminal is connected to the reference voltage, wherein the reference voltage is generated by the input voltage, the resistor, the voltage stabilizing tube and the ground interface.

[0018] Compared with the prior art, the system has excellent reliability and environmental adaptability with the assistance of the temperature adjusting assembly, can reliably start and stably work in a wide temperature range of-0°C to +25°C, avoids frequent on-off of the heating element at the critical temperature point in the hysteresis interval of temperature control, and significantly prolongs the service life of the heating sheet and the relay. Comprehensive protection circuit (overload, phase sequence, overheating, limit) ensures that the entire system can stop in time in abnormal conditions, and protects the core equipment from damage. In addition, it has strong anti-interference ability, can resist the conduction and radiation interference generated by the start and stop of high-power devices such as motors and contactors, and eliminates false actions. In addition, compared with simple on-off control, the phase-based voltage regulation control makes the motor run more smoothly, the speed is more accurate, reduces the starting impact and mechanical loss, and at the same time improves the energy efficiency, realizes accurate and efficient motor control. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present specification or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present specification, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0020] Figure 1 The circuit schematic diagram for driving a three-phase motor in the embodiment of the present application;

[0021] Figure 2 The schematic diagram of the zero-crossing detection circuit in the embodiment of the present application;

[0022] Figure 3 The schematic diagram of the gate drive circuit in the embodiment of the present application;

[0023] Figure 4 The electrical connection schematic diagram of the temperature adjusting assembly in the embodiment of the present application;

[0024] Figure 5 The schematic diagram of the three-stage anti-interference input circuit in the embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0026] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the term "connected" should be interpreted in a broad manner, for example, it can be fixedly connected, or detachably connected, or integrally connected, which can be mechanically connected, or electrically connected, which can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above-mentioned term in the present application can be understood according to the specific circumstances.

[0027] The terms "top", "bottom", "above", "under" and "on" used throughout the description are relative positions of components of the device, for example, the relative positions of the top and bottom substrates inside the device. It can be understood that the device is multifunctional, regardless of their orientation in space.

[0028] In order to facilitate the understanding of the embodiments of the present application, the following will be further explained and described with specific embodiments in conjunction with the accompanying drawings, and the embodiments do not constitute a limitation on the embodiments of the present application.

[0029] The present embodiment provides a wind tower lifting machine control system, as shown in Figures 1-4 .

[0030] The wind tower lifting machine control system comprises a three-phase motor driving assembly, a temperature adjusting assembly and a safety protection and state detection assembly.

[0031] The three-phase motor driving assembly comprises a three-phase six-arm topology structure, a zero-crossing detection circuit and a gate drive circuit, which is used to drive a three-phase AC motor and can control its speed. Among them, the zero-crossing detection circuit ensures that the MCU can control at the correct phase point of the AC power, realizing smooth voltage regulation, rather than simple on-off.

[0032] The three-phase six-arm topology structure comprises 6 MOSFETs corresponding to Q8, Q9, Q10, Q11, Q12 and Q13, and each phase is composed of two MOSFETs in reverse series, that is, Q8 and Q9 constitute phase A, Q10 and Q11 constitute phase B, and Q12 and Q13 constitute phase C. Two MOSFETs in reverse series control the positive half cycle and the negative half cycle of the AC power respectively. As Figure 1As shown, for each phase, for the convenience of description, taking phase A as an example, including input, upper arm switch, lower arm switch and output. The input is A_IN interface, accessing direct current; the output is A_OUT interface, connected to the A phase winding of the three-phase motor. The upper arm switch is responsible for the positive half cycle, including, A_IN interface is connected to the drain D of Q9 in turn, the source S of Q9, the anode of M7 diode D20, the cathode of M7 diode D20 and A_OUT interface. The control point G of the gate of Q9 is marked as AQG2, controlled by the drive circuit. The lower arm switch is responsible for the negative half cycle, including, A_OUT interface is connected to the drain D of Q8 in turn, the source S of Q8, the cathode of M7 diode D19, the anode of D19 and A_IN interface. The control point G of the gate of Q8 is marked as AQG1, controlled by the drive circuit.

[0033] Zero-crossing detection circuit, such as Figure 2 As shown, including zero-crossing detection of positive half cycle and zero-crossing detection of negative half cycle.

[0034] Among them, the zero-crossing detection of the positive half cycle takes optocoupler U6 as the core device, the A_IN interface is connected to the cathode of the primary side of U6, and N_IN (zero line) is connected to the anode of the primary side of U6 through current limiting resistors R40 and R41. The collector of the secondary side of U6 is connected to the PB7 pin of the MCU, and the emitter is grounded. When the A phase voltage is positive and high enough, U6 is turned on, and PB7 forms a +3.3V voltage; when the voltage approaches zero, U6 is cut off, and the PB7 pin is 0 voltage. Therefore, PB7 will produce a rising edge at the starting point of the positive half cycle (zero-crossing point).

[0035] The zero-crossing detection of the negative half cycle takes optocoupler U7 as the core device, the N_IN interface is connected to the anode of the primary side of U7, and the A_IN interface is connected to the cathode of the primary side of U7 through current limiting resistors R42 and R43. This reverse connection makes it work in the negative half cycle. The collector of the secondary side of U7 is connected to the PD14 pin of the MCU. PD14 will produce a rising edge at the starting point of the negative half cycle (zero-crossing point).

[0036] The gate drive circuit safely and effectively converts the weak control signal of the MCU into a strong signal that can drive the power MOSFET, and the gate drive circuit includes upper arm drive and lower arm drive.

[0037] As shown in Figure 3As shown, the upper arm drive outputs a PWM signal through the PB1 pin of the MCU, PB1 is connected to the primary side of the optocoupler OP16, and the secondary side of OP16 is responsible for driving the gate of Q9. The secondary side of OP16 requires a separate, floating power supply V2. This power supply is generated by an isolated DC-DC module, and its ground is connected to the source S of Q9, denoted as AQS2. Through the above, the output of the secondary side of OP16 is directly connected between the gate AQG2 and the source AQS2 of Q9. In this way, when OP16 is turned on, a voltage sufficient to turn on Q9 (such as 12-15V) is established between AQG2 and AQS2.

[0038] The lower arm drive outputs a PWM signal through the PB0 pin of the MCU, PB0 is connected to the primary side of the optocoupler OP13, and the secondary side of OP13 is powered by another isolated power supply V1. Since the source of Q8 is directly connected to the main circuit, its drive circuit is relatively simple. The output of the secondary side of OP13 is connected between the gate AQG1 and the source AQS1 of Q8.

[0039] Through the above settings, when A_IN is in the sine phase, A_IN cannot pass through D19 due to the presence of D19, which is unilaterally turned on, and A_IN passes through Q9 to A_OUT to the load motor. After U34 obtains the starting zero-crossing point signal of the positive half cycle of the A phase, it can drive OP16 by PB1, OP16 is turned on to drive Q9 to A_OUT. U34 controls the output of PB1 by duty cycle control to control the voltage of AQG2 and AQS2 of Q9, so that Q9 works in the variable resistance region, making the circuit form a series resistance voltage division mode, causing the output voltage of A_OUT to change, thereby changing the speed of the motor P19 connected to A_OUT. When U34 detects that A_IN reaches the end zero-crossing point of the positive half cycle, it stops the output of PB1, causing Q9 to turn off. At this moment, A_IN is not connected to A_OUT. The circuit path during the negative half cycle is the same as during the positive half cycle, which is A_OUT to Q8 to D19. The control circuit is OP13 and the drive pin is PB0.

[0040] Through the high-precision zero-crossing detection circuit (optocoupler isolation), the MCU is provided with an absolute phase reference point of the AC sine wave; the MCU can accurately know the starting and ending time of each half cycle, so as to output the PWM wave in the correct phase interval, control the MOSFET (such as Q9, Q8) to work in the variable resistance region, and realize "clipping" type regulation of the output voltage. This is equivalent to using a relatively simple hardware to achieve fine control of the phase regulation, which can effectively regulate the speed and is lower in cost than a full-featured frequency converter, and is particularly suitable for occasions where the speed regulation performance is not extremely demanding but better than simple on-off control.

[0041] The three-phase motor driving assembly cooperates with the three-phase six-arm topology, the zero-crossing detection circuit and the gate driving circuit to accurately control the voltage applied to the A-phase winding of the motor, so as to realize speed regulation. The structures of the B-phase and the C-phase are completely same as the A-phase, forming a complete three-phase driving system.

[0042] This system is specially adapted to the three-phase motor of the elevator. First, the "zero-crossing detection circuit" accurately captures the "running rhythm" of the three-phase power (A, B, C phase) - that is, it can identify the starting and ending time of each phase of alternating current positive and negative half cycle in real time (the phase difference of three-phase power is kept at 120° to ensure synchronous detection), providing accurate "time reference" for subsequent control. At the same time, the 6-way isolated switching power supply in the circuit outputs 6-way independent stable 15V power supply, which is specially used to power the 6 field effect transistors of the driving motor, avoiding signal interference between different devices and ensuring stable power supply. When the elevator starts, the control chip will drive the corresponding optocoupler and field effect transistor through the pin (such as PB0, PB1, etc.) according to the "rhythm" detected by the zero-crossing point: instead of making the field effect transistor fully conductive at once, it gradually increases the voltage output to the motor by adjusting the "duty ratio" (simply put, it controls the on-time ratio of the field effect transistor) - for example, starting from low voltage, gradually adjusting the duty ratio, the voltage gradually approaches the rated value, and the motor speed also gradually increases from slow to fast, smoothly rising to the rated speed, without the "sudden rush" situation. When stopping, the circuit will operate in the opposite direction: according to the zero-crossing point signal, gradually reduce the on-time ratio of the field effect transistor, and gradually reduce the motor voltage, so that the motor speed decreases smoothly to stop, completely avoiding the shaking caused by "emergency stop". The whole process does not rely on expensive frequency converters, but only through accurate circuit control to achieve the soft start effect close to the frequency converter, greatly reducing the cost, while also improving the riding comfort and the service life of mechanical parts.

[0043] The temperature adjusting assembly includes an input end, a first temperature switch SW1, a second temperature switch SW2, a solid-state relay KM1 and a heating sheet.

[0044] As Figure 4As shown, the input end includes a VCCP interface and a GND2 interface, wherein the VCCP interface provides operating power for the entire temperature control circuit, and the GND2 interface is used for grounding. The temperature sensing and control logic part includes a first temperature switch SW1, a second temperature switch SW2, a solid state relay KM1, and a heating sheet. The first temperature switch serves as a low-temperature start sensor and is in a normally closed state. When the ambient temperature is less than 0°C, the switch remains closed; when the temperature is greater than 0°C, the switch is opened. The second temperature switch serves as a high-temperature stop sensor and is in a normally closed state. When the ambient temperature is less than 25°C, the switch remains closed; when the temperature is greater than 25°C, the switch is opened. The solid state relay KM1 serves as an electronic switch, controls the main power path of the heating sheet, and provides a self-locking function, and has a coil including a pin 1 and a pin 2. When the coil is powered, the common end COM and the normally open end NO of the internal switch are attracted. The heating sheet serves as the final execution element and converts electrical energy into heat energy.

[0045] The connection mode of the above device includes that one end of the SW1 is directly connected to the operating power input end VCCP, and the other end is connected to one end of the heating sheet and the pin 1 of the coil of the KM1; one end of the SW2 is connected to the pin 2 of the coil of the KM1, and the other end is connected to the power ground interface GND2. The common end COM of the KM1 is directly connected to the VCCP interface, and the normally open end NO is connected to one end of the heating sheet and is combined with the connection point of the SW1 and the pin 1 of the coil.

[0046] When the temperature is lower than 0°C, the SW1 is closed, the SW2 is closed, the KM1 is not powered, and the common end and the normally open end are in an open state, the current flows through the VCCP, the closed SW1, the heating sheet, the pin 1 of the coil of the KM1, the pin 2 of the coil of the KM1, the closed SW2, and the GND2 in sequence. Correspondingly, the following actions are generated: the KM1 coil is powered and attracted, the common end COM and the normally open end NO of the KM1 are connected, and the heating sheet starts to heat. Since the heating sheet is located upstream of the KM1 coil, as long as the KM1 attraction condition is met, the heating sheet will work.

[0047] The heating sheet continues to work, and the temperature continues to rise. When the temperature rises to above 0°C, the SW1 is opened. The SW2 still remains closed. In this process, the current flows through the VCCP, the common end COM of the KM1, the normally open end NO of the KM1, the heating sheet, the pin 1 of the coil of the KM1, the pin 2 of the coil of the KM1, the closed SW2, and the GND2 in sequence. Correspondingly, the following actions are generated: although the SW1 is opened, the KM1 coil continues to obtain current through the normally open contact of itself and remains in the attracted state. That is, it is “self-locked”; the heating sheet continues to heat. The above process realizes the start threshold of 0°C and the stop threshold of 25°C, forms a 0-25°C temperature interval, and avoids repeated start and stop at the single temperature point of 0°C.

[0048] The heating element continues to operate, and the temperature continues to rise. When the temperature rises above 25°C, SW2 will disconnect. During this process, the following actions will occur: regardless of whether the path is via SW1 or KM1 self-locking, it will be cut off due to the disconnection of SW2; the KM1 coil is de-energized and released, and its common terminal is disconnected from the normally open terminal; the heating element completely stops working; and the self-locking state is released.

[0049] After heating stops, the temperature begins to drop naturally. When the temperature drops below 25°C, SW2 will close again, but since SW1 is open above 0°C and KM1's self-locking has been released, the circuit will not start. Only when the temperature drops below 0°C again and SW1 closes again will the circuit repeat the above process and begin a new heating cycle.

[0050] The temperature control component uses two physical temperature switches (0°C normally closed and 25°C normally closed) combined with a relay (KM1) to create a 0-25°C temperature range, thus achieving dual-threshold hysteresis control. It also features a clever self-locking mechanism: after startup, a self-locking mechanism is established through the normally open contact of KM1, ensuring heating continues even if the 0°C switch is open (temperature > 0°C) until the 25°C switch activates. Furthermore, this component is implemented entirely in hardware; its control logic is formed entirely by the hardware link of the relay and temperature switches, without software dependence, resulting in fast response, extremely high reliability, and low cost.

[0051] The safety protection and status monitoring components include signal acquisition and anti-interference processing, software logic and status management, and protection action execution.

[0052] The signal acquisition and anti-interference processing section, as a hardware defense line, is the key to ensuring the authenticity and reliability of the signal, mainly targeting switch signals.

[0053] Specifically, this includes a three-level anti-interference input circuit, such as Figure 5 As shown, taking the OVER_LOAD input of the overload sensor as an example (connected to PC10 in the corresponding circuit diagram), the first stage is magnetic ring suppression, the second stage is RC attenuation, and the third stage is a voltage comparator. In the first stage, the signal first passes through a magnetic ring (such as L22). The magnetic ring presents high impedance to high-frequency noise, effectively absorbing transient and radiated interference on the line. In the second stage, the signal then passes through a low-pass filter formed by a resistor (such as R59) and a capacitor, further attenuating the glitches and reducing their amplitude. In the third stage, the processed signal is sent to a voltage comparator composed of an operational amplifier (such as U19A). This three-stage anti-interference input circuit provides a composite anti-interference scheme of "wideband absorption + amplitude discrimination," filtering out interference from both energy and voltage dimensions, greatly improving stability in harsh industrial environments.

[0054] The signal input and preliminary filtering are completed by the first and second stages, and the flow path is: the OVER_LOAD signal from the outside flows through the magnetic ring L22 and the resistor R59 (2KΩ) in turn. Among them, the magnetic ring L22 is equivalent to a high-frequency choke coil, which absorbs transient peak pulses and radio frequency interference on the line. The resistor R59 and the subsequent circuit form a filter network and attenuate the interference signal.

[0055] The third stage completes voltage comparison and threshold judgment, including connecting the operational amplifier U19A into a voltage comparator mode, connecting the filtered OVER_LOAD signal to pin 12 corresponding to the non-inverting input (+), and connecting a 9.1V precision reference voltage to pin 13 corresponding to the inverting input (-). The reference voltage is generated by the circuit +12V2→R60 (2KΩ)→ZD1 (9.1V zener tube)→GND2, and a stable 9.1V voltage is generated at the cathode of ZD1 and directly sent to pin 13 of U19A.

[0056] In addition, electrical isolation and signal conversion are realized by the optocoupler OP8. The anode of the primary side of OP8 is connected to the output (pin 14) of U19A through a current limiting resistor (usually connected in series with the output in the schematic diagram), and the cathode is connected to GND2. The collector of the secondary side of OP8 is connected to the +3.3V power supply, and the emitter is connected to the PC10 pin of the MCU and is pulled up to +3.3V through a pull-up resistor R66 (20KΩ).

[0057] Only when the input OVER_LOAD signal voltage exceeds 9.1V, the comparator will output (pin 14) high level, and the primary side light emitting diode of OP8 will conduct and emit light. The secondary side phototransistor is turned on by light, which pulls the PC10 pin to a low level close to GND. Therefore, in the normal state (no overload), PC10 is high (3.3V); when overload occurs, PC10 is pulled low (0V). This "low active" design helps to detect line breakage faults.

[0058] The amplitude of common interference pulses is difficult to reach 9.1V, so it is effectively filtered out. Only the real effective and powerful switching action signal can be recognized by the system, greatly improving the anti-interference ability. The three-stage anti-interference input circuit processes overload detection signals, motor overheating detection signals, phase sequence error detection signals, limit switches (such as top / bottom limit, top / bottom profile, etc.) signals, emergency stop detection signals and access control detection signals.

[0059] The software logic and state management part serves as an intelligent defense line, and the MCU (STM32) is responsible for logical analysis and decision-making of all collected clean signals.

[0060] Its input mapping converts the state of the physical world (switch on / off, sensor trigger) through a series of hardware circuits into level changes of MCU GPIO pins, which are read by the software program. Its output mapping converts decisions and variables in the software program, such as stop_motor(), into control of specific GPIO pins (output low level), which are then passed through the drive circuit to control power devices (such as turning off MOSFET). Its logic implementation includes in the software, through conditional judgment, state machine, interrupt service program, etc., to associate inputs and outputs according to the pre-set safety rules and functional logic.

[0061] The protection action execution part serves as the final line of defense, and when the MCU determines that a fault has occurred, it will immediately execute a series of protection actions. Specifically, it includes immediately cutting off the motor drive, activating the brake, and triggering the audible and light alarms.

[0062] Among them, immediately cutting off the motor drive includes the MCU setting the PWM output to low level, the optocoupler being disconnected, the MOSFET being turned off, and the motor being powered off. The process flow includes MCU → PWM pins (PB0, PB1, PB3, PB4...) → drive optocoupler (OP13, OP16...) → power MOSFET (Q8-Q13).

[0063] Activating the brake includes the MCU outputting a high level to drive the relay to attract, and the brake being powered on to release (or powered off to hold tight, depending on the safety design). The process flow includes MCU → brake control pin (e.g. PC8) → transistor drive circuit → brake relay (KM3 / KM4).

[0064] Triggering the audible and light alarms includes the MCU outputting PWM or level to drive the peripherals to issue an alarm. The process flow includes MCU → alarm control pin (e.g. PC9) → transistor → buzzer (BZ1) / indicator light.

[0065] With the assistance of the temperature regulation assembly, the system has excellent reliability and environmental adaptability, can reliably start and work stably in a wide temperature range of -0°C to +25°C, and the hysteresis interval of temperature control avoids frequent on-off of the heating element at the critical temperature point, significantly prolonging the service life of the heating sheet and the relay. Comprehensive protection circuit (overload, phase sequence, overheating, limit) ensures that the entire system can shut down in time in abnormal conditions, protecting the core equipment from damage. In addition, it has strong anti-interference ability and can resist the conduction and radiation interference generated by the start and stop of high-power devices such as motors and contactors, eliminating false actions. In addition, compared to simple on-off control, phase-based voltage regulation control makes the motor run more smoothly, the speed is more precise, reduces the starting impact and mechanical loss, and at the same time improves the energy efficiency, achieving precise and efficient motor control.

[0066] The above detailed description of the specific implementation is further detailed for the purpose of the application, technical solutions and beneficial effects, and it should be understood that the above description is only for the specific implementation of the application and is not used to limit the protection scope of the application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A wind turbine tower lift control system, characterized by, The application relates to a three-phase motor driving assembly, a temperature adjusting assembly and a safety protection and state detecting assembly. The three-phase motor driving assembly comprises a circuit formed by sequentially electrically connecting a three-phase alternating voltage, a zero-crossing detection circuit, a controller, a gate drive circuit, a three-phase six-arm topology structure and a three-phase motor, and the input of the three-phase six-arm topology structure further comprises the three-phase alternating voltage; the zero-crossing detection circuit comprises an optical coupler, the primary side of the optical coupler is connected with the input of a certain phase voltage, the secondary side of the optical coupler is connected with a pin of the controller, the on-off of the optical coupler is changed when the voltage degree passes through a zero point, the corresponding pin generates a zero-crossing signal, the controller outputs a corresponding PWM signal according to the zero-crossing signal obtained by the pin, triggers the upper arm drive and the lower arm drive of the gate drive circuit, the three-phase six-arm topology structure outputs based on the three-phase alternating voltage and the triggered gate drive circuit, and the phase and speed of the three-phase motor are controlled; The temperature adjusting assembly comprises a first temperature switch, a second temperature switch, a solid-state relay and a heating sheet; when the temperature is lower than a preset low temperature, a first circuit is turned on, and the heating sheet starts heating; when the temperature is higher than the preset low temperature and lower than a preset high temperature, a second circuit is turned on, the solid-state relay is in a self-locking stage, and the heating sheet continues heating; when the temperature is higher than the preset high temperature, the self-locking heat preservation state is released, and the temperature is reduced to be lower than the preset low temperature again, so that the temperature rising process is repeated; The safety protection and state detecting assembly comprises a software logic and state management part which processes signals output by a signal collecting and anti-interference processing part, triggers a protection action execution part to implement corresponding actions to realize safety protection.

2. The windmill tower lift control system of claim 1, wherein, The temperature adjusting assembly comprises that one end of the first temperature switch is directly connected to a working power input end VCCP, and the other end is connected to one end of the heating sheet and a pin 1 of a solid-state relay coil; one end of the second temperature switch is connected to a pin 2 of the solid-state relay coil, and the other end is connected to a power ground interface GND2; a common end COM of the solid-state relay is directly connected to the VCCP interface, and a normally open end NO is connected to one end of the heating sheet and is combined with the connection point of the first temperature switch and the pin 1 of the coil.

3. The windmill tower lift control system of claim 1, wherein, When the temperature is lower than the preset low temperature, the first circuit is turned on, current flows through the working power input end VCCP, the closed first temperature switch, the heating sheet, the pin 1 of the solid-state relay coil, the pin 2 of the solid-state relay coil, the closed second temperature switch and the ground interface in sequence, and the following actions are generated: the solid-state relay coil is energized and attracted, the common end COM and the normally open end NO of the solid-state relay are connected, and the heating sheet starts heating.

4. The wind turbine tower lift control system of claim 1, wherein, When the temperature is higher than the preset low temperature and lower than the preset high temperature, the second circuit is turned on, the solid-state relay is in the self-locking stage, current flows through the working power input end VCCP, the common end COM of the solid-state relay, the normally open end NO of the solid-state relay, the heating sheet, the pin 1 of the solid-state relay coil, the pin 2 of the solid-state relay coil, the closed second temperature switch and the ground interface in sequence, and the following actions are generated: the first temperature switch is turned off, the solid-state relay coil continuously obtains current through the normally open contact point of the solid-state relay, the heating sheet is heated.

5. The wind turbine tower lift control system of claim 1, wherein, When the temperature is higher than the preset high temperature, the self-locking heat preservation state is released, the first circuit and / or the second circuit are cut off by the disconnection of the second temperature switch, the solid state relay coil is released by power-off, the common end is disconnected with the normally open end, the heating sheet completely stops working, and the self-locking state is released.

6. The wind turbine tower lift control system of claim 1, wherein, The zero-crossing detection circuit comprises positive half-cycle zero-crossing detection and negative half-cycle zero-crossing detection. The positive half-cycle zero-crossing detection comprises a first optocoupler, a certain phase of three-phase alternating voltage is connected to the cathode of the original side of the first optocoupler, the zero line is connected to the anode of the original side of the first optocoupler, the collector of the secondary side of the first optocoupler is connected to the pin of the controller, and the emitter is grounded. The negative half-cycle zero-crossing detection comprises a second optocoupler, a certain phase of three-phase alternating voltage is connected to the cathode of the original side of the second optocoupler, the zero line is connected to the anode of the original side of the second optocoupler, the collector of the secondary side of the first optocoupler is connected to the pin of the controller, and the emitter is grounded.

7. The wind turbine tower lift control system of claim 1, wherein, The signal acquisition and anti-interference processing part comprises three-stage anti-interference input circuits, the first stage is magnetic ring suppression, the second stage is RC attenuation, and the third stage is a voltage comparator.

8. The wind turbine tower lift control system of claim 7, wherein, The third stage comprises a third optocoupler, the anode of the original side of the third optocoupler is connected to the output of the operational amplifier through a current-limiting resistor, the cathode of the original side of the third optocoupler is connected to the ground interface, the collector of the secondary side of the third optocoupler is connected to the +3.3V power supply, and the emitter is connected to the controller.

9. The wind turbine tower lift control system of claim 7, wherein, The anode of the input end of the operational amplifier is connected to the signal filtered by the first stage and the second stage, and the cathode of the input end is connected to a reference voltage, wherein the reference voltage is generated by an input voltage, a resistor, a voltage stabilizing tube and a ground interface.

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