A construction hoist brake holding control system

Abstract

The application discloses a construction hoist brake holding control system and belongs to the technical field of intelligent control, which comprises a 380V power supply, an LLC resonant converter, a brake holding control circuit, an LLC control circuit and an MCU control circuit, wherein the LLC resonant converter comprises an EMC circuit, a front-stage rectification filter circuit, an LLC resonant circuit and a full-bridge rectification filter circuit. The main topology scheme adopted by the application is an LLC resonant converter plus double-path IGBT control plus output voltage and current detection scheme. The LLC converts the alternating voltage of 380V into the direct voltage of 195V+ / -15V, and then the voltage is output to the brake holding for power supply through the control of IGBT. Voltage detection and current detection circuits are added in the whole output loop. In the working process, the MCU can monitor the brake holding logic, detect the output voltage and current, and judge whether the brake holding has faults such as short circuit, open circuit, overload, overcurrent, overvoltage, undervoltage, unstable output voltage, IGBT through and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent control, and particularly relates to a construction hoist brake control system. BACKGROUND

[0002] The current construction hoist brake control system large circuit adopts a form of a power frequency transformer, a rectifier bridge and a contactor control. The power frequency transformer for a three-drive motor is usually large in weight and size. The entire machine type cannot be further optimized in terms of logistics costs, and cannot be miniaturized and lightened in product design. In addition, the scheme is an open-loop control, and the output voltage will increase or decrease with the increase or decrease of the power grid. The output voltage cannot be compensated. In a normal case, the rated working voltage of the brake is DC 195V. When the power grid fluctuates, the output voltage is too low, and the brake cannot work normally during the operation of the hoist. The brake fails and the brake is abraded. This working condition can cause the hoist to fail to operate normally. When the output voltage of the power frequency transformer is too high, the brake will have a high temperature rise, and there is a risk of brake burnout and failure. This is a working condition that is not allowed for the construction hoist. In addition, the scheme does not monitor the output voltage, the current and the action state of the contactor. When the contactor malfunctions, the brake state cannot be effectively monitored. At this time, the construction hoist has a risk of sliding down, which is a situation that must be avoided. Finally, the control mode of the contactor has a large delay, which affects the comfort control of the hoist. SUMMARY

[0003] The present application aims to provide a construction hoist brake control system to solve the problems in the background art.

[0004] To achieve the above object, the present application provides the following technical scheme.

[0005] The application discloses a construction hoist brake holding control system, which comprises a 380V power supply, an LLC resonant converter, a brake holding control circuit, an LLC control circuit and an MCU control circuit, wherein the LLC resonant converter comprises an EMC circuit, a pre-stage rectification filter circuit, an LLC resonant circuit and a full-bridge rectification filter circuit; the 380V power supply is connected with the EMC circuit; the EMC circuit, the pre-stage rectification filter circuit, the LLC resonant circuit, the full-bridge rectification filter circuit and the brake holding control circuit are sequentially connected; the pre-stage rectification filter circuit, the LLC resonant circuit and the full-bridge rectification filter circuit are connected with the LLC control circuit; the brake holding control circuit is further connected with the MCU control circuit; the LLC resonant converter converts the voltage of the 380V power supply into a direct current voltage of 195V±15V; the voltage is output to the brake holding control circuit for power supply through the LLC resonant circuit; the MCU control circuit judges whether the brake holding exists short circuit, open circuit, overload, overcurrent, overvoltage, undervoltage, unstable output voltage and IGBT through monitoring the brake holding logic and detecting the output voltage and current.

[0006] As a further scheme of the application, the auxiliary power supply is further arranged, and the auxiliary power supply is connected with the pre-stage rectification filter circuit, the LLC control circuit and the MCU control circuit respectively.

[0007] As a further scheme of the application, the EMC circuit comprises an inductor L1, a capacitor C1, a capacitor C2 and a capacitor C3; the inductor L1 has three paths, one end of each path is connected with three ports of the 380V power supply respectively, and the other end of each path is connected with the capacitor C1, the capacitor C2 and the capacitor C3 respectively.

[0008] As a further scheme of the application, the pre-stage rectification filter circuit comprises a diode D1, a diode D2, a diode D3, a diode D4, a diode D5, a diode D6, a resistor R1, a switch K1 and a capacitor C4; the anode of the diode D1 is connected with the cathode of the diode D4, the capacitor C1 and the first path interface of the inductor L1; the anode of the diode D2 is connected with the cathode of the diode D5, the capacitor C2 and the second path interface of the inductor L1; the anode of the diode D3 is connected with the cathode of the diode D6, the capacitor C3 and the third path interface of the inductor L1; the cathode of the diode D1 is connected with the cathode of the diode D2, the cathode of the diode D3, the resistor R1 and the switch K1; the other end of the resistor R1 is connected with the other end of the switch K1, the capacitor C4, the LLC control circuit and the auxiliary power supply; the anode of the diode D4 is connected with the anode of the diode D5, the anode of the diode D6, the other end of the capacitor C4 and the LLC control circuit.

[0009] As a further scheme of the present application: the LLC resonant part is composed of IGBT tube Q1, IGBT tube Q2, inductor L2, transformer T1, capacitor C5 and resistor R2, the drain of IGBT tube Q1 is connected with resistor R1 and capacitor C4, the gate of IGBT tube Q1 is connected with LCC control circuit, the source of IGBT tube Q1 is connected with the drain of IGBT tube Q2 and inductor L2, the source of IGBT tube Q1 is connected with resistor R2 and auxiliary power supply, the other end of inductor L2 is connected with one end of the primary winding of transformer T1, the other end of the primary winding of transformer T1 is connected with the other end of resistor R2 and LCC control circuit through capacitor C5.

[0010] As a further scheme of the present application: the full-bridge rectification filtering part is composed of diode D7, diode D8, diode D9, diode D10 and capacitor C5, the anode of diode D7 is connected with one end of the secondary winding of transformer T1 and the cathode of diode D9, the anode of diode D8 is connected with the other end of the secondary winding of transformer T1 and the cathode of diode D10, the cathode of diode D7 is connected with the cathode of diode D8, capacitor C5 and LCC control circuit, the anode of diode D9 is connected with the anode of diode D10 and LCC control circuit.

[0011] As a further scheme of the present application: the clutch control circuit is composed of inductor L3, diode D11, triode Q3, resistor RV1, diode D12, resistor R3, triode Q4 and capacitor detection module CT1, one end of inductor L3 is connected with the cathode of diode D11 and the cathode of diode D7, the other end of inductor L3 is connected with the anode of diode D11 and the collector of triode Q3, the emitter of triode Q3 is connected with resistor RV1, the cathode of diode D12 and control coil KD, the base of triode Q3 is connected with MCU control circuit, the other end of resistor RV1 is connected with resistor R3, the collector of triode Q4 and the other end of control coil KD, the emitter of triode Q4 is connected with capacitor detection module CT1, capacitor detection module CT1 is connected with MCU control circuit, the base of triode Q4 is connected with MCU control circuit, control coil KD is also connected with motor M.

[0012] As a further scheme of the present application: the resistor RV1 is variable resistor.

[0013] Compared with the prior art, the application has the beneficial effects that: the main topology scheme adopted by the application is the scheme of LLC resonant converter plus double-path IGBT control plus output voltage and current detection, LLC converts the voltage of 380V AC into the voltage of 195V±15V DC (the output can be adjusted according to the rated voltage of the brake, closed-loop control), and then the voltage is output to the brake control circuit for power supply through the LLC resonant circuit, and the voltage detection and current detection circuit are added in the whole output loop, and in the working process, the MCU can monitor the brake logic and detect the output voltage and current to determine whether the brake has the faults of short circuit, open circuit, overload, overcurrent, overvoltage, undervoltage, unstable output voltage, IGBT through and the like. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 The circuit diagram of the application.

[0015] Figure 2 The brake operation logic flowchart. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only circuit embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0017] Embodiment 1: please refer to Figure 1 and Figure 2 A construction hoist brake control system, comprising a 380V power supply, an LLC resonant converter, a brake control circuit, an LLC control circuit and an MCU control circuit, the LLC resonant converter comprises an EMC circuit, a front-stage rectification filter circuit, an LLC resonant circuit and a full-bridge rectification filter circuit, the 380V power supply is input to the EMC circuit, the EMC circuit, the front-stage rectification filter circuit, the LLC resonant circuit, the full-bridge rectification filter circuit and the brake control circuit are connected in sequence, the front-stage rectification filter circuit, the LLC resonant circuit and the full-bridge rectification filter circuit are connected with the LLC control circuit, the brake control circuit is further connected with the MCU control circuit, the LLC resonant converter converts the voltage of the 380V power supply into the voltage of 195V±15V DC, the voltage is output to the brake control circuit for power supply through the LLC resonant circuit, the MCU control circuit monitors the brake logic and detects the output voltage and current to determine whether the brake has the faults of short circuit, open circuit, overload, overcurrent, overvoltage, undervoltage, unstable output voltage, IGBT through and the like. The auxiliary power supply is further included, and the auxiliary power supply is connected with the front-stage rectification filter circuit, the LLC control circuit and the MCU control circuit respectively.

[0018] LLC resonant converter has high efficiency, small volume and high power density; IGBT has fast control response, and the control response time can be adjusted through software, so it has more adjustment space in comfort. In addition, the double-channel IGBT has redundancy measures, when one of them loses control, the other can control the brake output, which does not affect the actual use. In addition, combined with output voltage and current monitoring, it can detect whether the IGBT is damaged, and also can monitor the working state of the brake, prevent misoperation, so as to improve the reliability of the whole system. Finally, IGBT also has the characteristics of small size and high power density. The combination of the two schemes can save cost and reduce product volume on the whole machine structure, reduce the actual weight of the product on the logistics transportation, save logistics cost, and improve the reliability of the brake.

[0019] In example 2, on the basis of example 1, the EMC circuit includes inductance L1, capacitance C1, capacitance C2 and capacitance C3. The inductance L1 has three paths, one end of which is connected to three ports of the 380V power supply respectively, and the other end is connected to the capacitance C1, the capacitance C2 and the capacitance C3 respectively.

[0020] The pre-stage rectification filter circuit includes diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, resistor R1, switch K1 and capacitor C4. The anode of diode D1 is connected to the cathode of diode D4, the first path interface of inductance L1 and capacitance C1. The anode of diode D2 is connected to the cathode of diode D5, the second path interface of inductance L1 and capacitance C2. The anode of diode D3 is connected to the cathode of diode D6, the third path interface of inductance L1 and capacitance C3. The cathode of diode D1 is connected to the cathode of diode D2, the cathode of diode D3, resistor R1 and switch K1. The other end of resistor R1 is connected to the other end of switch K1, capacitor C4, LCC control circuit and auxiliary power supply. The anode of diode D4 is connected to the anode of diode D5, the anode of diode D6, the other end of capacitor C4 and LCC control circuit.

[0021] The LLC resonant part is composed of IGBT tube Q1, IGBT tube Q2, inductance L2, transformer T1, capacitance C5 and resistor R2. The drain of IGBT tube Q1 is connected to resistor R1 and capacitor C4. The gate of IGBT tube Q1 is connected to LCC control circuit. The source of IGBT tube Q1 is connected to the drain of IGBT tube Q2 and inductance L2. The source of IGBT tube Q1 is connected to resistor R2 and auxiliary power supply. The other end of inductance L2 is connected to one end of primary winding of transformer T1. The other end of primary winding of transformer T1 is connected to the other end of resistor R2 and LCC control circuit through capacitor C5.

[0022] The full-bridge rectification filter part is composed of diode D7, diode D8, diode D9, diode D10 and capacitor C5, the anode of diode D7 is connected with one end of the secondary winding of transformer T1 and the cathode of diode D9, the anode of diode D8 is connected with the other end of the secondary winding of transformer T1 and the cathode of diode D10, the cathode of diode D7 is connected with the cathode of diode D8, capacitor C5 and LCC control circuit, and the anode of diode D9 is connected with the anode of diode D10 and LCC control circuit.

[0023] The brake control circuit is composed of inductor L3, diode D11, triode Q3, resistor RV1, diode D12, resistor R3, triode Q4 and capacitor detection module CT1, one end of inductor L3 is connected with the cathode of diode D11 and the cathode of diode D7, the other end of inductor L3 is connected with the anode of diode D11 and the collector of triode Q3, the emitter of triode Q3 is connected with resistor RV1, the cathode of diode D12 and control coil KD, the base of triode Q3 is connected with MCU control circuit, the other end of resistor RV1 is connected with resistor R3, the collector of triode Q4 and the other end of control coil KD, the emitter of triode Q4 is connected with capacitor detection module CT1, capacitor detection module CT1 is connected with MCU control circuit, the base of triode Q4 is connected with MCU control circuit, and control coil KD is also connected with motor M.

[0024] The LLC resonant converter of the design can achieve an efficiency of more than 90%, the input voltage can reach a wide range of AC380±60V (unidirectional input, three-phase input is available), closed-loop control is adopted, the output voltage can be stabilized at DC200V by detecting the voltage across C5, over-load protection, over-current protection and output short-circuit protection functions can be completed by detecting the working current through device R2, and the design can well replace the power frequency transformer in terms of performance, size and weight.

[0025] In the normal working process, device L3 and D11 can inhibit pulse current, and in the short-circuit process, device L3 and D11 can inhibit sharp peak current, thereby protecting the latter Q3 and Q4 (IGBT) from damage.

[0026] Q3 and Q4 are large-capacity IGBT devices, compared with conventional contactors, have controllable delay time, fast control response, no noise, small size, small loss, long service life and other advantages.

[0027] Device CT1 is a brake current detection device, which can monitor the output current of the brake controller in real time, compared with conventional devices without current detection function, can effectively avoid the risk of brake misoperation and uncontrolled construction elevator.

[0028] RV1, R3, D12 as clutch freewheeling device, can absorb the peak generated at the clutch off instant, can protect the clutch circuit from the interference of the peak to cause damage, can improve the reliability of the whole system.

[0029] It will be apparent to those skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No feature of the application is to be construed as a limitation thereon unless it is expressly stated to be such.

[0030] Furthermore, it should be understood that although the description herein is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description herein is made in this way only for the sake of clarity, and those skilled in the art should consider the description as a whole, and the technical solutions in each embodiment can also be properly combined to form other embodiments which can be understood by those skilled in the art.

Claims

1. A construction elevator brake control system, comprising a 380V power supply, an LLC resonant converter, a brake control circuit, an LLC control circuit, and an MCU control circuit, characterized in that: The LLC resonant converter includes an EMC circuit, a pre-stage rectifier and filter circuit, an LLC resonant circuit, and a full-bridge rectifier and filter circuit. A 380V power supply inputs the EMC circuit. The EMC circuit, the pre-stage rectifier and filter circuit, the LLC resonant circuit, the full-bridge rectifier and filter circuit, and the brake control circuit are connected in sequence. The pre-stage rectifier and filter circuit, the LLC resonant circuit, and the full-bridge rectifier and filter circuit are all connected to the LLC control circuit. The brake control circuit is also connected to the MCU control circuit. The LLC resonant converter converts the voltage of the 380V power supply into a DC voltage of 195V±15V, which is output to the brake control circuit through the LLC resonant circuit to power the brake control circuit. The MCU control circuit monitors the brake logic and detects the output voltage and current to determine whether the brake has a short circuit, open circuit, overload, overcurrent, overvoltage, undervoltage, unstable output voltage, or IGBT straight-through fault. The LLC resonant part is composed of an IGBT tube Q1, an IGBT tube Q2, an inductor L2, a transformer T1, a capacitor C5 and a resistor R2. The drain of the IGBT tube Q1 is connected to the resistor R1 and the capacitor C4, the gate of the IGBT tube Q1 is connected to the LCC control circuit, the source of the IGBT tube Q1 is connected to the drain of the IGBT tube Q2 and the inductor L2, the source of the IGBT tube Q1 is connected to the resistor R2 and the auxiliary power supply, the other end of the inductor L2 is connected to one end of the primary winding of the transformer T1, and the other end of the primary winding of the transformer T1 is connected to the other end of the resistor R2 and the LCC control circuit through the capacitor C5; The brake control circuit is composed of an inductor L3, a diode D11, a transistor Q3, a resistor RV1, a diode D12, a resistor R3, a transistor Q4 and a capacitance detection module CT1. One end of the inductor L3 is connected to the cathode of the diode D11 and the cathode of the diode D7, the other end of the inductor L3 is connected to the anode of the diode D11 and the collector of the transistor Q3, the emitter of the transistor Q3 is connected to the resistor RV1, the cathode of the diode D12 and the control coil KD, the base of the transistor Q3 is connected to the MCU control circuit, the other end of the resistor RV1 is connected to the resistor R3, the collector of the transistor Q4 and the other end of the control coil KD, the emitter of the transistor Q4 is connected to the capacitance detection module CT1, the capacitance detection module CT1 is connected to the MCU control circuit, the base of the transistor Q4 is connected to the MCU control circuit, and the control coil KD is also connected to the motor M.

2. A construction elevator brake control system according to claim 1, characterized in that: It also includes an auxiliary power supply, which is respectively connected to the front-stage rectifier and filter circuit, the LLC control circuit and the MCU control circuit.

3. A construction elevator brake control system according to claim 1, characterized in that: The EMC circuit includes an inductor L1, a capacitor C1, a capacitor C2 and a capacitor C3. The inductor L1 has three paths, one end of which is connected to three ports of a 380V power supply respectively, and the other end is connected to the capacitor C1, the capacitor C2 and the capacitor C3 respectively.

4. A construction elevator brake control system according to claim 3, characterized in that: The front-stage rectifier and filter circuit includes a diode D1, a diode D2, a diode D3, a diode D4, a diode D5, a diode D6, a resistor R1, a switch K1 and a capacitor C4. The anode of the diode D1 is connected to the cathode of the diode D4, the capacitor C1 and a first interface of the inductor L1. The anode of the diode D2 is connected to the cathode of the diode D5, the capacitor C2 and the second interface of the inductor L1. The anode of the diode D3 is connected to the cathode of the diode D6, the capacitor C3 and the third interface of the inductor L1. The cathode of the diode D1 is connected to the cathode of the diode D2, the cathode of the diode D3, the resistor R1 and the switch K1. The other end of the resistor R1 is connected to the other end of the switch K1, the capacitor C4, the LCC control circuit and the auxiliary power supply. The anode of the diode D4 is connected to the anode of the diode D5, the anode of the diode D6, the other end of the capacitor C4 and the LCC control circuit.

5. A construction elevator brake control system according to claim 4, characterized in that: The full-bridge rectifier filter circuit is composed of a diode D7, a diode D8, a diode D9, a diode D10 and a capacitor C5. The anode of the diode D7 is connected to one end of the secondary winding of the transformer T1 and the cathode of the diode D9. The anode of the diode D8 is connected to the other end of the secondary winding of the transformer T1 and the cathode of the diode D10. The cathode of the diode D7 is connected to the cathode of the diode D8, the capacitor C5 and the LCC control circuit. The anode of the diode D9 is connected to the anode of the diode D10 and the LCC control circuit.

6. A construction elevator brake control system according to claim 5, characterized in that: The resistor RV1 is a variable resistor.

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