Control system and method of three-phase asynchronous motor

Abstract

The invention discloses a control system and method for a three-phase asynchronous motor. The control system comprises a main system control circuit, a standby system control circuit and a switching switch. The main system control circuit is formed by combining a main system control module, a main system power supply board, a main system driving board and a main system alternating current contact board; the standby system control circuit is formed by combining a standby system control module, a standby system power supply board, a standby system driving board and a standby system alternating current contact board; wherein when the main system control circuit detects that the collected monitoring information is not matched with the stored monitoring information, the main system control circuit is powered off through the switching switch, and the standby system control circuit is powered on. Therefore, the circuits corresponding to the functional plates in the control system all adopt independent board card design, and the board cards of the main system and the standby system can be mutually inserted and interchanged, so that the board card of the fault system can be directly replaced when any one system breaks down, the maintenance efficiency is further effectively improved, and the normal operation of the three-phase asynchronous motor is not influenced in the maintenance process.

Description

Technical Field

[0001] The present application relates to the technical field of motor control, and in particular to a control system and method for a three-phase asynchronous motor. Background Art

[0002] The equivalent circuit of the three-phase asynchronous motor is composed of resistance and inductance elements, and a large reverse current may be generated during the charging and discharging process. Therefore, the existing motor control circuit usually adopts a three-phase inverter. However, due to factors such as motor starting, forward and reverse rotation, and load changes, the control voltage of the motor will change, causing electronic components (such as field effect transistors, central processing units (CPUs), etc.) to be subjected to reverse shocks, thereby damaging the electronic components and affecting the normal operation of the three-phase asynchronous motor.

[0003] Therefore, in order not to affect the normal operation of the three-phase asynchronous motor, the prior art provides an on-chip dual-machine redundant dual-channel electric servo mechanism control circuit, which mainly uses a redundant FPGA chip as a core component, and its peripheral superimposed power supply, three-phase bridge chip, solid-state relay, A / D sampler, main-standby switching circuit and necessary interface circuit, so that the entire dual-channel electric servo mechanism control algorithm and dual-machine redundant backup can be implemented in a single PCB, so that when problems occur in the operation of the three-phase asynchronous motor, the normal operation of the three-phase asynchronous motor can be quickly restored.

[0004] However, the prior art adopts single-phase power rectification and an inverter bridge circuit. Therefore, when a high-power motor is used, it will cause three-phase power imbalance and damage the bridge circuit, thereby causing an impact on the power grid. In addition, the design of an integrated board is adopted. When any system fails, it will be difficult to repair and replace, and the three-phase asynchronous motor will stop running during maintenance. Summary of the invention

[0005] Based on the above-mentioned deficiencies of the prior art, the present application provides a control system and method for a three-phase asynchronous motor to solve the problem brought about by the prior art that when any system fails, maintenance will cause the three-phase asynchronous motor to stop running.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] In a first aspect, the present application provides a control system for a three-phase asynchronous motor, the control system comprising: a main system control circuit, a standby system control circuit and a disconnection switch;

[0008] The main system control circuit is composed of a main system control module, a main system power supply board, a main system drive board and a main system AC contact board;

[0009] The standby system control circuit is composed of a standby system control module, a standby system power supply board, a standby system drive board and a standby system AC contact board;

[0010] The external three-phase power supply is respectively connected to the three-phase input terminal of the main system power supply board and the three-phase input terminal of the standby system power supply board;

[0011] The three-phase output end of the main system power supply board is connected to the three-phase input end of the main system drive board, and the output end of the main system power supply board is connected to the first input end of the main system control template;

[0012] The input end of the main system drive board is connected to the first output end of the main system control template, and the three-phase output end of the main system drive board is connected to the three-phase input end of the main system AC contact board;

[0013] The three-phase output terminals of the main system AC contact plate are respectively connected to the three-phase asynchronous motor and the three-phase input terminals of the main system control module;

[0014] The third input terminal and the second output terminal of the main system control module are connected to the standby system control module, and the dual system IO interface of the main system control module is connected to the dual system IO interface of the standby system control module through the motherboard;

[0015] The three-phase output end of the standby system power board is connected to the three-phase input end of the standby system drive board, and the output end of the standby system power board is connected to the first input end of the standby system control template;

[0016] The input end of the standby system driving board is connected to the first output end of the standby system control template, and the three-phase output end of the standby system driving board is connected to the three-phase input end of the standby system AC contact board;

[0017] The three-phase output terminals of the standby system AC contact plate are respectively connected to the three-phase input terminals of the three-phase asynchronous motor and the standby system control module;

[0018] The system cut-off switch is connected to the second input terminal of the main system control module and the second input terminal of the standby system control module respectively;

[0019] Among them, when the main system control circuit detects that the collected monitoring information does not match the stored monitoring information, the power supply of the main system control circuit is disconnected by the disconnection switch, and the power supply of the standby system control circuit is turned on to enable the normal operation of the three-phase asynchronous motor.

[0020] Optionally, in the above-mentioned three-phase asynchronous motor control system, the main system control module includes: a main system control board, a main system CF card, a main system status indication module, a main system status switching relay, a main system voltage acquisition module, a main system three-phase half-bridge driver, a main system motor voltage and current acquisition module and a first resistor;

[0021] The dual-system IO interface of the main system control board is connected to the dual-system IO interface of the standby system control module through the motherboard, the first input terminal and the first output terminal of the main system control board are connected to the main system CF card, the second input terminal of the main system control board is connected to the system cut-off switch, the third input terminal and the third output terminal of the main system control board are connected to the main system state switching relay, the fourth input terminal of the main system control board is connected to the output terminal of the main system voltage acquisition module, the fifth input terminal of the main system control board is connected to the output terminal of the main system motor voltage and current acquisition module, the first output terminal of the main system control board is connected to the input terminal of the main system state indication module, and the second output terminal of the main system control board is connected to the input terminal of the main system three-phase half-bridge drive;

[0022] The first input terminal and the first output terminal of the main system state switching relay are connected to the standby system control module, and the second output terminal of the main system state switching relay is connected to the main system control board through the first resistor;

[0023] The input end of the main system voltage acquisition module is connected to the output end of the main system power supply board;

[0024] The output end of the main system three-phase half-bridge driver is connected to the input end of the main system driver board;

[0025] The three-phase input terminal of the main system motor voltage and current acquisition module is connected to the three-phase asynchronous motor.

[0026] Optionally, in the above-mentioned control system of the three-phase asynchronous motor, the main system power board is composed of a main three-phase transformer and a main three-phase rectifier bridge;

[0027] The three-phase input end of the main three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the main three-phase transformer is connected to the three-phase input end of the main three-phase rectifier bridge;

[0028] The three-phase output end of the main three-phase rectifier bridge is connected to the three-phase input end of the main system drive board, and the output end of the main three-phase rectifier bridge is connected to the first input end of the main system control template.

[0029] Optionally, in the control system of the above-mentioned three-phase asynchronous motor, the main system drive board is a main three-phase bridge circuit, and the main three-phase bridge circuit is composed of three groups of main processing modules, and one group of the main processing modules includes two main transistors; wherein the collector of the first main transistor and the emitter of the second main transistor are used together as the input end of the main processing module, and the emitter of the first main transistor and the collector of the second main transistor are used together as the output end of the main processing module; the input end of each group of main processing modules is used as the three-phase input end of the main three-phase bridge circuit, and the output end of each group of main processing modules is used as the three-phase output end of the main three-phase bridge circuit;

[0030] The three-phase input end of the main three-phase bridge circuit is connected to the three-phase output end of the main system power supply board, the input end of the main three-phase bridge circuit is connected to the first output end of the main system control template, and the three-phase output end of the main three-phase bridge circuit is connected to the three-phase input end of the main system AC contact board.

[0031] Optionally, in the control system of the above-mentioned three-phase asynchronous motor, the main system AC contact plate is composed of a combination of three main AC contactors; wherein the input end of each of the main AC contactors is used as the three-phase input end of the main system AC contact plate, and the output end of each of the main AC contactors is used as the three-phase output end of the main system AC contact plate.

[0032] Optionally, in the above-mentioned three-phase asynchronous motor control system, the standby control module includes: a standby control board, a standby CF card, a standby status indication module, a standby status switching relay, a standby voltage acquisition module, a standby three-phase half-bridge driver, a standby motor voltage and current acquisition module and a second resistor;

[0033] The dual-system IO interface of the standby system control board is connected to the dual-system IO interface of the main system control module through the motherboard, the first input end and the first output end of the standby system control board are connected to the standby system CF card, the second input end of the standby system control board is connected to the system cut-off switch, the third input end and the third output end of the standby system control board are connected to the standby system status switching relay, the fourth input end of the standby system control board is connected to the output end of the standby system voltage acquisition module, the fifth input end of the standby system control board is connected to the output end of the standby system motor voltage and current acquisition module, the first output end of the standby system control board is connected to the input end of the standby system status indication module, and the second output end of the standby system control board is connected to the input end of the standby system three-phase half-bridge drive;

[0034] The first input terminal and the first output terminal of the standby system status switching relay are connected to the standby system control module, and the second output terminal of the standby system status switching relay is connected to the standby system control board through the second resistor;

[0035] The input end of the standby system voltage acquisition module is connected to the output end of the standby system power board;

[0036] The output end of the standby system three-phase half-bridge driver is connected to the input end of the standby system driver board;

[0037] The three-phase input terminal of the motor voltage and current acquisition module of the standby system is connected to the three-phase asynchronous motor.

[0038] Optionally, in the above-mentioned control system of the three-phase asynchronous motor, the standby power supply board is composed of a standby three-phase transformer and a standby three-phase rectifier bridge;

[0039] The three-phase input end of the three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the three-phase transformer is connected to the three-phase input end of the three-phase rectifier bridge;

[0040] The three-phase output end of the standby three-phase rectifier bridge is connected to the three-phase input end of the standby system driving board, and the output end of the standby three-phase rectifier bridge is connected to the first input end of the standby system control template.

[0041] Optionally, in the control system of the above-mentioned three-phase asynchronous motor, the standby system driving board is a standby three-phase bridge circuit, and the standby three-phase bridge circuit is composed of three groups of standby processing modules, and one group of the standby processing modules includes two standby transistors; wherein the collector of the first standby transistor and the emitter of the second standby transistor are used together as the input end of the standby processing module, and the emitter of the first standby transistor and the collector of the second standby transistor are used together as the output end of the standby processing module; the input end of each group of standby processing modules is used as the three-phase input end of the standby three-phase bridge circuit, and the output end of each group of standby processing modules is used as the three-phase output end of the standby three-phase bridge circuit;

[0042] The three-phase input end of the standby three-phase bridge circuit is connected to the three-phase output end of the standby system power supply board, the input end of the standby three-phase bridge circuit is connected to the first output end of the standby system control template, and the three-phase output end of the standby three-phase bridge circuit is connected to the three-phase input end of the standby system AC contact board.

[0043] Optionally, in the control system of the above-mentioned three-phase asynchronous motor, the standby AC contact plate is composed of a combination of three standby AC contactors; wherein the input end of each of the standby AC contactors is commonly used as the three-phase input end of the standby AC contact plate, and the output end of each of the standby AC contactors is commonly used as the three-phase output end of the standby AC contact plate.

[0044] The second aspect of the present application provides a control method for a three-phase asynchronous motor, which is applied to a control system of a three-phase asynchronous motor disclosed in the first aspect above. The control method comprises:

[0045] When it is detected that the control system is powered on, the current mode of the main system control board is switched to a self-checking mode;

[0046] Acquire monitoring information through the main system control circuit and read all target monitoring information from the CF card;

[0047] Determine whether there is target monitoring information matching the monitoring information among all target monitoring information;

[0048] If there is target monitoring information matching the monitoring information in the target monitoring information, determining whether the main system control circuit meets a preset condition;

[0049] If the main system control circuit meets the preset conditions, the self-check mode of the main system control board is switched to the main system mode;

[0050] Real-time detection of whether the main system control circuit is faulty by the main system control panel;

[0051] If the main system control circuit fails, the fault process is executed and the power supply of the main system control circuit is disconnected by the disconnect switch;

[0052] The power supply of the standby system control circuit is turned on by the system cut-off switch to enable the normal operation of the three-phase asynchronous motor.

[0053] Optionally, in the above-mentioned control method for the three-phase asynchronous motor, after the main system control board detects in real time whether the main system control circuit is faulty, the method further comprises:

[0054] If the main system control circuit does not fail, the electrical information of the three-phase AC power output by the main system AC contact plate is obtained through the main system motor voltage and current acquisition module;

[0055] Outputting SVPWM waveform according to the electrical information through the main system control board;

[0056] The main system control board outputs a square wave according to the SVPWM control waveform, so as to drive the main system state relay to control the main system AC contact board to open each main AC contactor;

[0057] The operating parameters and synchronization signals of the main system control circuit are obtained through the main system control board, and the operating parameters and the synchronization signals are sent to the standby system control board, so that the standby system control board synchronously outputs the target SVPWM waveform according to the operating parameters and the synchronization signals.

[0058] Optionally, in the above-mentioned control method of the three-phase asynchronous motor, after determining whether the main system control circuit meets the preset conditions, it also includes:

[0059] If it is determined that the main system control circuit does not meet the preset condition, the power supply of the main system control circuit is disconnected by the system cut-off switch, and the power supply of the standby system control circuit is turned on;

[0060] Real-time detection of whether the standby system control circuit is faulty by the standby system control board;

[0061] If the standby system control circuit fails, the fault process is executed, and the power supply of the standby system control circuit is disconnected by the disconnect switch;

[0062] Turning on the power supply of the main system control circuit through the system cut-off switch to enable the normal operation of the three-phase asynchronous motor;

[0063] If the standby system control circuit does not fail, the standby system motor voltage and current acquisition module obtains the target electrical information of the target three-phase AC output by the standby system AC contact board, and receives the operating parameters and synchronization signals sent by the main system control board;

[0064] Synchronously outputting a target SVPWM waveform according to the operating parameters, the synchronization signal and the target electrical information;

[0065] The standby system control board outputs a target square wave according to the target SVPWM control waveform, so as to drive the standby system status relay to control the standby system AC contact board to close each main AC contactor.

[0066] Optionally, in the above-mentioned control method of the three-phase asynchronous motor, if the main system control circuit fails, a fault process is executed, including:

[0067] When the main system control circuit fails, the transmission function is stopped through the main system control board, and the level of the dual system IO is set to a high level;

[0068] After the main system control board sets a high level, the square wave output is stopped to close the main system status relay and each main AC contactor in the main system AC contact board.

[0069] Optionally, in the above-mentioned control method of the three-phase asynchronous motor, if the standby control circuit fails, a fault process is executed, including:

[0070] When the standby system control circuit fails, the transmission function is stopped through the standby system control board, and the level of the dual system IO is set to a high level;

[0071] After the standby system control board sets a high level, the target square wave is stopped from being output, so as to close the standby system status relay and each standby AC contactor in the standby system AC contact board.

[0072] The present application provides a control system for a three-phase asynchronous motor, the control system comprising: a main system control circuit, a standby system control circuit and a disconnect switch, the main system control circuit is composed of a main system control module, a main system power supply board, a main system drive board and a main system AC contact board, the standby system control circuit is composed of a standby system control module, a standby system power supply board, a standby system drive board and a standby system AC contact board, an external three-phase power supply is respectively connected to the three-phase input terminal of the main system power supply board and the three-phase input terminal of the standby system power supply board, the three-phase output terminal of the main system power supply board is connected to the three-phase input terminal of the main system drive board, the output terminal of the main system power supply board is connected to the first input terminal of the main system control template, the input terminal of the main system drive board is connected to the first output terminal of the main system control template, the three-phase output terminal of the main system drive board is connected to the three-phase input terminal of the main system AC contact board, the three-phase output terminal of the main system AC contact board is respectively connected to the three-phase asynchronous motor and the three-phase input terminal of the main system control module, and the three-phase output terminal of the main system control module is connected to the three-phase input terminal of the main system control template. The input end and the second output end are connected to the standby system control module, the dual-system IO interface of the main system control module is connected to the dual-system IO interface of the standby system control module through the motherboard, the three-phase output end of the standby system power supply board is connected to the three-phase input end of the standby system drive board, the output end of the standby system power supply board is connected to the first input end of the standby system control template, the input end of the standby system drive board is connected to the first output end of the standby system control template, the three-phase output end of the standby system drive board is connected to the three-phase input end of the standby system AC contact board, the three-phase output end of the standby system AC contact board is respectively connected to the three-phase asynchronous motor and the three-phase input end of the standby system control module, the disconnection switch is respectively connected to the second input end of the main system control module and the second input end of the standby system control module, wherein, when the main system control circuit detects that the collected monitoring information does not match the stored monitoring information, the power supply of the main system control circuit is disconnected by the disconnection switch, and the power supply of the standby system control circuit is turned on to enable the normal operation of the three-phase asynchronous motor. Therefore, the circuits corresponding to each functional module in the control system are designed using independent boards, and the boards of the main system and the standby system can be plugged and interchanged. When any system fails, the board of the faulty system can be directly replaced, thereby improving maintenance efficiency and not affecting the normal operation of the three-phase asynchronous motor during the maintenance process. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0074] Figure 1 A first circuit structure schematic diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0075] Figure 2 A second circuit structure schematic diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0076] Figure 3 A third circuit structure schematic diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0077] Figure 4 A fourth circuit structure schematic diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0078] Figure 5 A fifth circuit structure diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0079] Figure 6 A sixth circuit structure diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0080] Figure 7 A seventh circuit structure diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0081] Figure 8 An eighth circuit structure schematic diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0082] Fig. 9 A ninth circuit structure diagram of a control system for a three-phase asynchronous motor provided in an embodiment of the present application;

[0083] Fig.10 A layout diagram of a control system cage provided in an embodiment of the present application;

[0084] Fig.11 A schematic flow chart of a control method for a three-phase asynchronous motor provided in another embodiment of the present application;

[0085] Fig.12 A schematic diagram of the structure of a switching state machine provided in another embodiment of the present application;

[0086] Fig.13 A flowchart of a control method of a system control circuit provided by another embodiment of the present application;

[0087] Fig.14 A flowchart of a method for executing a fault process provided by another embodiment of the present application;

[0088] Fig.15 A schematic flow chart of a control method of a main system control circuit provided in another embodiment of the present application;

[0089] Fig.16 A flowchart of another method for executing a fault process provided in another embodiment of the present application. DETAILED DESCRIPTION

[0090] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0091] In this application, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0092] As can be seen from the background technology, the existing method of ensuring the normal operation of the three-phase asynchronous motor is mainly through using a redundant FPGA chip as the core component, and superimposing a power supply, a three-phase bridge chip, a solid-state relay, an A / D sampler, a main-standby switching circuit and a necessary interface circuit on its periphery, so that all dual-channel electric servo mechanism control algorithms and dual-machine redundant backup can be realized in a single PCB, so that when problems occur in the operation of the three-phase asynchronous motor, the normal operation of the three-phase asynchronous motor can be quickly restored. However, the existing circuit board adopts an integrated board design. When any system fails, it will be difficult to repair and replace, and the three-phase asynchronous motor will stop running during maintenance.

[0093] Therefore, an embodiment of the present application provides a control system for a three-phase asynchronous motor, which includes a main system control circuit, a standby system control circuit and a disconnect switch. The main system control circuit and the standby system control circuit are designed using independent board cards, and the main and standby system boards are interoperable, which is convenient for maintenance and will not affect the normal operation of the motor during the maintenance process.

[0094] So see Figure 1 , shows a first circuit structure schematic diagram of a control system of a three-phase asynchronous motor provided in an embodiment of the present application, the control system includes: a main system control circuit 1, a standby system control circuit 2 and a disconnect switch 3.

[0095] The main system control circuit 1 is composed of a main system control module 11 , a main system power supply board 12 , a main system drive board 13 and a main system AC contact board 14 .

[0096] The equipment control circuit 2 is composed of an equipment control module 21 , an equipment power supply board 22 , an equipment drive board 23 and an equipment AC contact board 24 .

[0097] It should be noted that both control circuits are composed of a control module, a power board, a drive board, and an AC contact board, and the boards of the same model in the two systems are universal boards. When one system fails, the board of the other system can be connected to each other to ensure the normal operation of the three-phase asynchronous motor M. Optionally, the two systems can be switched directly through the switching switch 3 without exchanging the boards, and the normal operation of the three-phase asynchronous motor M can also be maintained. Among them, the control module, the power board, the drive board, and the AC contact board are all independent boards and can be disassembled.

[0098] The external three-phase power supply is connected to the three-phase input terminals of the main system power supply board 12 and the three-phase input terminals of the standby system power supply board 22 respectively.

[0099] It can be understood that the external three-phase power supply will input 380V three-phase AC power. After being processed by the main system power supply board 12 and the standby system power supply board 22, the 380V three-phase AC power will be converted into 510V DC power to provide voltage for the main system drive board 13 and the standby system drive board 23. After being processed by the control module, the 510V DC power will be converted into 24V voltage to provide voltage for the main system control module 11 and the standby system control module 21.

[0100] The three-phase output terminal of the main system power supply board 12 is connected to the three-phase input terminal of the main system drive board 13, and the output terminal of the main system power supply board 12 is connected to the first input terminal of the main system control template.

[0101] The input end of the main system driving board 13 is connected to the first output end of the main system control template, and the three-phase output end of the main system driving board 13 is connected to the three-phase input end of the main system AC contact board 14 .

[0102] The three-phase output terminals of the main system AC contact plate 14 are connected to the three-phase asynchronous motor M and the three-phase input terminals of the main system control module 11 respectively.

[0103] The third input terminal and the second output terminal of the main system control module 11 are connected to the backup system control module 21 , and the dual system IO interface of the main system control module 11 is connected to the dual system IO interface of the backup system control module 21 through the motherboard.

[0104] It should be noted that there is also serial communication and IO communication between the two systems, so that the main system control module 11 sends operating data to the backup system control module 21, so that the backup system control module 21 synchronizes the data of the main system control module 11 and follows the operation of the main system control module 11.

[0105] In addition, when the main system control circuit 1 fails, the main system control circuit 1 can achieve seamless switching to the backup system control circuit 2.

[0106] The three-phase output terminal of the standby system power board 22 is connected to the three-phase input terminal of the standby system driving board 23, and the output terminal of the standby system power board 22 is connected to the first input terminal of the standby system control template.

[0107] The input end of the standby system driving board 23 is connected to the first output end of the standby system control template, and the three-phase output end of the standby system driving board 23 is connected to the three-phase input end of the standby system AC contact board 24 .

[0108] The three-phase output terminals of the equipment AC contact plate 24 are connected to the three-phase asynchronous motor M and the three-phase input terminals of the equipment control module 21 respectively.

[0109] The disconnect switch 3 is respectively connected to the second input terminal of the main system control module 11 and the second input terminal of the standby system control module 21. The disconnect switch 3 is used to switch the two system circuits to ensure the normal operation of the three-phase asynchronous motor M.

[0110] It should be noted that the three-phase input terminal and the three-phase output terminal described in the embodiment of the present application both refer to the access points of the three-phase power supply, namely the U phase, the V phase and the W phase, which are the interfaces for connecting the three-phase asynchronous motor M to the three-phase AC power supply. Each phase can be regarded as a separate AC power supply, thereby providing more stable and balanced power.

[0111] It should be emphasized that the main system control module 11 is the core of the control system, which includes a CPU processor, and can implement the SVPWM algorithm, thereby improving the performance of the three-phase asynchronous motor M drive system. Specifically, the SVPWM waveform output by the main system control module 11 is output to the three-phase half-bridge drive chip in the main system control module 11 through the optical coupling isolation in the main system power board 12, and the output of the three-phase half-bridge drive chip is connected to the drive end of the three-phase half-bridge circuit of the drive board (that is, the three-phase input end of the main system drive board 13), so as to monitor the voltage of the external three-phase power input, and monitor the voltage and current of the three-phase AC output by the main system AC contact board 14.

[0112] When the main system control circuit 1 detects that the collected monitoring information does not match the stored monitoring information, the power supply of the main system control circuit 1 is disconnected through the system switch 3, and the power supply of the standby system control circuit 2 is turned on to enable the normal operation of the three-phase asynchronous motor M.

[0113] In the embodiment of the present application, by connecting the system disconnector, the AC contact plate in the main system control circuit and the AC contact plate in the standby system control circuit to the three-phase asynchronous motor, the fault side can be completely physically disconnected, so that when switching is performed through the system disconnector, the purpose of seamless switching can be achieved, thereby preventing the three-phase asynchronous motor from being affected in any way.

[0114] In some embodiments, in combination Figure 1 , see Figure 2 , shows a second circuit structure schematic diagram of a control system of a three-phase asynchronous motor, the main system control module 11 includes: a main system control board, a main system CF card, a main system status indication module, a main system status switching relay, a main system voltage acquisition module, a main system three-phase half-bridge drive, a main system motor voltage and current acquisition module and a first resistor (KM1).

[0115] The dual-system IO interface of the main system control board is connected to the dual-system IO interface of the standby system control module 21 through the motherboard, the first input terminal and the first output terminal of the main system control board are connected to the main system CF card, the second input terminal of the main system control board is connected to the system cut-off switch 3, the third input terminal and the third output terminal of the main system control board are connected to the main system status switching relay, the fourth input terminal of the main system control board is connected to the output terminal of the main system voltage acquisition module, the fifth input terminal of the main system control board is connected to the output terminal of the main system motor voltage and current acquisition module, the first output terminal of the main system control board is connected to the input terminal of the main system status indication module, and the second output terminal of the main system control board is connected to the input terminal of the main system three-phase half-bridge drive.

[0116] Specifically, the main system CF card is used to store the data collected by the main system voltage acquisition module and the main system motor voltage and current acquisition module. The main system status indication module is the main system fault light. When the main system control circuit 1 fails, the main system fault light will light up. At this time, the main system control circuit 1 will be switched to the standby system control circuit 2 through the system switch 3.

[0117] The first input terminal and the first output terminal of the main system state switching relay are connected to the standby system control module 21, and the second output terminal of the main system state switching relay is connected to the main system control board through the first resistor. Specifically, the first input terminal and the first output terminal of the main system state switching relay are connected to the standby system state switching relay in the standby system control module 21.

[0118] It should be noted that the main system state switching relay is a main-standby switching relay interlocking circuit, and the main system state switching relay includes a safety circuit, a safety static circuit, and two static interlocking relays. The safety circuit input is the 10k square wave output by the main system control board, and the output is the safety static circuit and the 24V voltage of the drive node. The static interlocking relay input is the control signal of the main system control board and the static interlocking relay output in the standby system control module 21. The four static interlocking relays of the two systems constitute an electrical interlocking structure. At the same time, only one system finally outputs 24V voltage, attracts the AC contactor in its own system, and then connects the 380V AC output of the drive board in its own system to the motor to make the motor run.

[0119] The input end of the main system voltage acquisition module is connected to the output end of the main system power supply board 12 .

[0120] Specifically, the main system voltage acquisition module is used to collect the three-phase alternating current input by the external three-phase power supply and send it to the main system control board.

[0121] The output end of the main system three-phase half-bridge driver is connected to the input end of the main system driver board 13 .

[0122] Specifically, the main system three-phase half-bridge driver is used to output SVPWM waveform to drive the main system driver board 13 .

[0123] The three-phase input terminal of the main system motor voltage and current acquisition module is connected to the three-phase asynchronous motor M.

[0124] Specifically, the main system motor voltage and current acquisition module is used to collect the voltage and current values ​​of the three-phase AC power output by the main system AC contact plate 14, and send the collected voltage and current values ​​to the main system control board.

[0125] It should be noted that the control system will read the data of the main CF card, configure the parameters and time of the main system control module 11, and during operation, the main system control module 11 will store the monitoring information in the main CF card, so that the main system control module 11 can check the software and hardware in real time, monitor safety and output, and monitor the static interlock relay to complete the system cutting operation.

[0126] In the embodiment of the present application, through the main system control board, the main system CF card, the main system status indication module, the main system status switching relay, the main system voltage acquisition module, the main system three-phase half-bridge drive, the main system motor voltage and current acquisition module and the first resistor, it is possible to achieve precise control, real-time monitoring and effective protection of the three-phase asynchronous motor, thereby improving the stability and safety of the three-phase asynchronous motor.

[0127] In some embodiments, in combination Figure 1 and Figure 2 , see Figure 3, shows a third circuit structure schematic diagram of a control system of a three-phase asynchronous motor, where the main power supply board 12 is composed of a main three-phase transformer and a main three-phase rectifier bridge.

[0128] The three-phase input end of the main three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the main three-phase transformer is connected to the three-phase input end of the main three-phase rectifier bridge.

[0129] The three-phase output end of the main three-phase rectifier bridge is connected to the three-phase input end of the main system drive board 13, and the output end of the main three-phase rectifier bridge is connected to the first input end of the main system control template.

[0130] In some embodiments, the main three-phase transformer is a three-phase YY transformer, and the main three-phase rectifier bridge is composed of 6 reverse diodes and two capacitors, which are connected in a bridge type and are responsible for converting three-phase AC power into DC power. Therefore, after the 380V three-phase AC power input from the external three-phase power supply is isolated by the three-phase YY transformer and then filtered by the main three-phase rectifier bridge, it will be converted into 510V DC power to provide voltage for the main drive board.

[0131] In the embodiment of the present application, the main three-phase transformer and the main three-phase rectifier bridge can ensure the electrical isolation of the two systems without mutual interference.

[0132] In some embodiments, in combination Figure 1 , Figure 2 as well as Figure 3 , see Figure 4 , shows a fourth circuit structure schematic diagram of a control system of a three-phase asynchronous motor, the main system drive board 13 is a main three-phase bridge circuit, the main three-phase bridge circuit is composed of three groups of main processing modules, and one group of main processing modules includes two main transistors.

[0133] The collector of the first main transistor and the emitter of the second main transistor are used together as the input end of the main processing module, and the emitter of the first main transistor and the collector of the second main transistor are used together as the output end of the main processing module. The input end of each group of main processing modules is used as the three-phase input end of the main three-phase bridge circuit, and the output end of each group of main processing modules is used as the three-phase output end of the main three-phase bridge circuit.

[0134] The three-phase input end of the main three-phase bridge circuit is connected to the three-phase output end of the main system power supply board 12, the input end of the main three-phase bridge circuit is connected to the first output end of the main system control template, and the three-phase output end of the main three-phase bridge circuit is connected to the three-phase input end of the main system AC contact board 14.

[0135] In some embodiments, the main three-phase bridge circuit is composed of 6 IGBTs (Insulated Gate Bipolar Transistor), each IGBT controls the current of one motor phase to form a complete three-phase power supply. The six IGBTs are usually divided into two groups: the upper tube and the lower tube of each phase, which are used to control the on and off of the current. Each pair of IGBTs (upper tube and lower tube) is responsible for controlling the current flow of one phase, thereby realizing the forward and reverse rotation of the motor. Each IGBT is connected to the corresponding phase of the three-phase asynchronous motor M, so that the current can flow in the three-phase winding of the three-phase asynchronous motor M.

[0136] Optionally, the main three-phase bridge circuit can also be a three-phase half-bridge circuit, with the input being the 510V DC output of the main power board and the SVPWM control waveform (and 380V AC) output by the main system control module 11. The output of the main three-phase bridge circuit is 380V AC, which is output to the AC contact plate.

[0137] In the embodiment of the present application, the driving of the three-phase asynchronous motor is achieved by six IGBTs in the main three-phase bridge circuit, which has a flexible control method and efficient energy conversion capability.

[0138] In some embodiments, in combination Figure 1 , Figure 2 , Figure 3 as well as Figure 4 , see Figure 5 , shows a fifth circuit structure schematic diagram of a control system of a three-phase asynchronous motor, where the main AC contact plate 14 is composed of three main AC contactors.

[0139] The input end of each main AC contactor is used as the three-phase input end of the main system AC contact plate 14 , and the output end of each main AC contactor is used as the three-phase output end of the main system AC contact plate 14 .

[0140] It should be noted that the main system AC contact plate 14 is only composed of an AC contactor, and the input is the 380V AC output of the drive board, and the control signal output by the main system control module 11 and the main system state switching relay. The output of the main system AC contact plate 14 is connected to the three-phase asynchronous motor M. It should also be noted that due to the interlocking of the static relays of the two systems, only the two ends of the AC contactor in the main system AC contact plate 14 of one system are connected at the same time. Among them, the AC contactor is driven by the main system control module 11 and the main system state switching relay.

[0141] In the embodiment of the present application, the main system AC contact plate can prevent the SVPWM waveforms output by the dual systems from simultaneously controlling the three-phase asynchronous motor, causing the three-phase asynchronous motor to be unable to operate normally.

[0142] In some embodiments, in combination Figure 1 , Figure 2 , Figure 3 , Figure 4 as well as Figure 5 , see Figure 6 , showing a sixth circuit structure schematic diagram of a control system of a three-phase asynchronous motor, the standby system control module 21 includes: a standby system control board, a standby system CF card, a standby system status indication module, a standby system status switching relay, a standby system voltage acquisition module, a standby system three-phase half-bridge drive, a standby system motor voltage and current acquisition module and a second resistor (KM2).

[0143] The dual-system IO interface of the standby system control board is connected to the dual-system IO interface of the main system control module through the motherboard, the first input terminal and the first output terminal of the standby system control board are connected to the standby system CF card, the second input terminal of the standby system control board is connected to the system cut-off switch 3, the third input terminal and the third output terminal of the standby system control board are connected to the standby system status switching relay, the fourth input terminal of the standby system control board is connected to the output terminal of the standby system voltage acquisition module, the fifth input terminal of the standby system control board is connected to the output terminal of the standby system motor voltage and current acquisition module, the first output terminal of the standby system control board is connected to the input terminal of the standby system status indication module, and the second output terminal of the standby system control board is connected to the input terminal of the standby system three-phase half-bridge drive.

[0144] The first input terminal and the first output terminal of the standby system status switching relay are connected to the standby system control module 21 , and the second output terminal of the standby system status switching relay is connected to the standby system control board via a second resistor.

[0145] The input end of the standby system voltage acquisition module is connected to the output end of the standby system power board 22 .

[0146] The output end of the standby three-phase half-bridge driver is connected to the input end of the standby driver board 23 .

[0147] The three-phase input terminal of the motor voltage and current acquisition module of the equipment system is connected to the three-phase asynchronous motor M.

[0148] It should be noted that the specific implementation method of the standby system control module including: a standby system control board, a standby system CF card, a standby system status indication module, a standby system status switching relay, a standby system voltage acquisition module, a standby system three-phase half-bridge drive, a standby system motor voltage and current acquisition module and a second resistor (KM2) and the specific implementation method of the main system control module including: a main system control board, a main system CF card, a main system status indication module, a main system status switching relay, a main system voltage acquisition module, a main system three-phase half-bridge drive, a main system motor voltage and current acquisition module and a first resistor (KM1) are only different in the implementation objects, and the specific implementation methods are the same. Therefore, the specific implementation method of the standby system control module can refer to the main system control module in the above embodiment accordingly, and will not be repeated here.

[0149] In some embodiments, in combination Figure 1 , Figure 2 , Figure 3 , Figure 4 Figure 5 , Figure 6 , see Figure 7 , shows a seventh circuit structure diagram of a control system of a three-phase asynchronous motor, wherein the system power board 22 is composed of a three-phase transformer and a three-phase rectifier bridge.

[0150] The three-phase input end of the standby three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the standby three-phase transformer is connected to the three-phase input end of the standby three-phase rectifier bridge.

[0151] The three-phase output end of the three-phase rectifier bridge is connected to the three-phase input end of the system drive board 23, and the output end of the three-phase rectifier bridge is connected to the first input end of the system control template.

[0152] It should be noted that the specific implementation method of the standby power board and the main power board are only different in the implementation objects, and the specific implementation methods are the same. Therefore, the specific implementation method of the standby power board can refer to the main power board in the above embodiment accordingly, and will not be repeated here.

[0153] In some embodiments, in combination Figure 1 , Figure 2 , Figure 3 , Figure 4 Figure 5 , Figure 6 as well as Figure 7 , see Figure 8 , shows an eighth circuit structure diagram of a control system of a three-phase asynchronous motor, wherein the standby system driving board 23 is a standby three-phase bridge circuit, which is composed of three groups of standby processing modules, and one group of standby processing modules includes two standby transistors. Among them, the collector of the first standby transistor and the emitter of the second standby transistor are used together as the input end of the standby processing module, and the emitter of the first standby transistor and the collector of the second standby transistor are used together as the output end of the standby processing module. The input end of each group of standby processing modules is used as the three-phase input end of the standby three-phase bridge circuit, and the output end of each group of standby processing modules is used as the three-phase output end of the standby three-phase bridge circuit.

[0154] The three-phase input end of the three-phase bridge circuit is connected to the three-phase output end of the system power supply board 22, the input end of the three-phase bridge circuit is connected to the first output end of the system control template, and the three-phase output end of the three-phase bridge circuit is connected to the three-phase input end of the system AC contact board 24.

[0155] It should be noted that the specific implementation of the standby system drive board and the main system drive board are only different in the implementation objects, and the specific implementation methods are the same. Therefore, the specific implementation method of the standby system drive board can refer to the main system drive board in the above embodiment, and will not be repeated here.

[0156] In some embodiments, in combination Figure 1 , Figure 2 , Figure 3 , Figure 4 Figure 5 , Figure 6 , Figure 7 as well as Figure 8 , see Fig. 9 The ninth circuit structure diagram of a control system of a three-phase asynchronous motor is shown, wherein the standby AC contact plate 24 is composed of three standby AC contactors. The input end of each standby AC contactor is used as the three-phase input end of the standby AC contact plate 24, and the output end of each standby AC contactor is used as the three-phase output end of the standby AC contact plate 24.

[0157] It should be noted that the specific implementation of the standby system AC contact plate and the main system AC contact plate are only different in the implementation objects, and the specific implementation methods are the same. Therefore, the specific implementation method of the standby system AC contact plate can refer to the standby system AC contact plate in the above embodiment accordingly, and will not be repeated here.

[0158] It should be emphasized that in the control system of the three-phase asynchronous motor provided in the embodiment of the present application, an indication switching circuit (ZS) is also included, which is composed of a main fault indicator light, a backup fault indicator light and a disconnect switch 3. The two systems are arranged symmetrically in the cage, and the motherboard electrically connects the boards together, and the three-phase power supply and motor output wiring are led out from the back of the motherboard. Each board can be pulled out and replaced separately. The two systems are completely electrically isolated, and the power supplies do not affect each other. Plugging in and out a board of one system and / or a failure of one system will not affect the operation of the board of the other system. When one system fails and the other system operates normally, the operation of the three-phase asynchronous motor M will not be affected, and the replacement and maintenance of the board on the faulty side will be completed. When the faulty side is restored, it can also be put into operation according to the backup system control circuit 2. Fig.10 This is the layout of the control system cage. The five boards on the left and the five boards on the right can be removed individually. The middle ZS board is connected to the motherboard through welding wires and cannot be removed individually. ZS is only for indication and disconnection. Failure does not affect the normal use of the equipment. Specifically, ZS corresponds to Fig. 9 The main system status indication module and the standby system status indication module in DY correspond to Fig. 9 The left dotted box part of the main system power board 12 and the standby system power board 22, KZ corresponds to Fig. 9 The main system control module 11 and the standby system control module 21 in QD correspond to Fig. 9The middle dotted box part in the main system drive board 13 and the standby system drive board 23, JD corresponds to Fig. 9 The main system status switching relay and the standby system status switching relay in JC correspond to Fig. 9 The dotted frame part on the middle right is the main system AC contact plate and the standby system AC contact plate.

[0159] The present application provides a control system for a three-phase asynchronous motor, the control system comprising: a main system control circuit, a standby system control circuit and a disconnect switch, the main system control circuit is composed of a main system control module, a main system power supply board, a main system drive board and a main system AC contact board, the standby system control circuit is composed of a standby system control module, a standby system power supply board, a standby system drive board and a standby system AC contact board, an external three-phase power supply is respectively connected to the three-phase input terminal of the main system power supply board and the three-phase input terminal of the standby system power supply board, the three-phase output terminal of the main system power supply board is connected to the three-phase input terminal of the main system drive board, the output terminal of the main system power supply board is connected to the first input terminal of the main system control template, the input terminal of the main system drive board is connected to the first output terminal of the main system control template, the three-phase output terminal of the main system drive board is connected to the three-phase input terminal of the main system AC contact board, the three-phase output terminal of the main system AC contact board is respectively connected to the three-phase asynchronous motor and the three-phase input terminal of the main system control module, and the three-phase output terminal of the main system control module is connected to the three-phase input terminal of the main system control template. The input end and the second output end are connected to the standby system control module, the dual-system IO interface of the main system control module is connected to the dual-system IO interface of the standby system control module through the motherboard, the three-phase output end of the standby system power supply board is connected to the three-phase input end of the standby system drive board, the output end of the standby system power supply board is connected to the first input end of the standby system control template, the input end of the standby system drive board is connected to the first output end of the standby system control template, the three-phase output end of the standby system drive board is connected to the three-phase input end of the standby system AC contact board, the three-phase output end of the standby system AC contact board is respectively connected to the three-phase asynchronous motor and the three-phase input end of the standby system control module, the disconnection switch is respectively connected to the second input end of the main system control module and the second input end of the standby system control module, wherein, when the main system control circuit detects that the collected monitoring information does not match the stored monitoring information, the power supply of the main system control circuit is disconnected by the disconnection switch, and the power supply of the standby system control circuit is turned on to enable the normal operation of the three-phase asynchronous motor. Therefore, the circuits corresponding to each functional module in the control system are designed using independent boards, and the boards of the main system and the standby system can be plugged and interchanged. When any system fails, the board of the faulty system can be directly replaced, thereby improving maintenance efficiency and not affecting the normal operation of the three-phase asynchronous motor during the maintenance process.

[0160] A control system for a three-phase asynchronous motor provided in the above-mentioned embodiment of the present application is shown in FIG. Fig.11 , shows a flow chart of a control method for a three-phase asynchronous motor provided in an embodiment of the present application, the method comprising:

[0161] S1101. When it is detected that the control system is powered on, the current mode of the main system control board is switched to a self-check mode.

[0162] It should be noted that when it is detected that the control system is powered on and the control system initialization time is less than 10s, the CPU of the main system control board will automatically enter the IDEL mode, that is, it needs to self-check the hardware circuit to find out whether there is any fault in itself.

[0163] It should also be noted that when the main system control panel is in IDEL state, panels D1-D4 light up in sequence, and the indicator light on the cut-off system panel goes out.

[0164] S1102, acquiring monitoring information through the main system control circuit, and reading all target monitoring information from the CF card.

[0165] It can be understood that when the main system control board is in the IDEL state, the main system control board in the main system control circuit will first self-check whether there is any internal fault. Therefore, it is necessary to collect the voltage of the external three-phase power input through the main system voltage acquisition module in the main system control circuit, and collect the voltage and current of the three-phase AC power output by the main system AC contact board through the main system motor voltage and current acquisition module in the main system control circuit. Therefore, the monitoring information obtained through the main system control circuit can include the voltage of the external three-phase power input and the voltage and current of the three-phase AC power. Then all target monitoring information needs to be read from the CF card so that it can self-check its own hardware circuit.

[0166] S1103: Determine whether there is target monitoring information matching the monitoring information among all target monitoring information.

[0167] Specifically, if there is target monitoring information matching the monitoring information among all target monitoring information, it means that the main system control circuit has passed the self-test, so step S1104 can be executed at this time.

[0168] If there is no target monitoring information matching the monitoring information among all target monitoring information, it means that the main system control circuit self-test has not passed, which can also mean that there is a fault in the main system control circuit. Therefore, it is necessary to switch the main system control circuit to the standby system control circuit through the system cut-off switch so that the standby system control circuit can maintain the normal operation of the three-phase asynchronous motor.

[0169] S1104, determine whether the main system control circuit meets the preset conditions.

[0170] It should be noted that when there is target monitoring information matching the monitoring information in the target monitoring information, the main system control board will output a 10k square wave by default, drive the safety and circuit in the main system state switching relay, output a static relay drive signal, and continuously check the safety and interlock relay node signals to enable the main system control board to complete the state jump and enter MAS (main system) or SLA (standby system) by default. Therefore, in order to know which mode the main system control board jumps from the IDEL adjustment mode, it can be determined whether the main system control circuit meets the preset conditions. There are two preset conditions, one is condition A: the initialization check passes, the hardware is fault-free, the software check is normal, the other system interlock relay is not sucked up, and the interlock relay of this system is sucked up. The other is condition D: the main system control circuit operates normally, the hardware is fault-free, the software operates normally, the system switch is turned from automatic to the main of the system, and the interlock relay of this system is sucked up.

[0171] It should also be noted that in addition to the above two conditions, there are two more conditions: Condition B: IDEL switches to SLA, the initialization check passes, the hardware has no faults, the software check is normal, the other system interlock relay is attracted, and the interlock relay of this system is not attracted. Condition C: Normal operation, no hardware faults, the software runs normally, and the system switch is turned from automatic to another system main. Condition E: There is an abnormality in the operation check, or the hardware check fails, or the software self-check fails. For details, please refer to Fig.12 The structural diagram of the switching state machine is shown in FIG.

[0172] Therefore, if the main system control circuit meets the preset conditions, step S1105 is executed.

[0173] Optionally, after executing step S1104, Fig.13 As shown, the following steps are also included:

[0174] S1301. If the main system control circuit does not meet the preset conditions, the power supply of the main system control circuit is disconnected by the system switch, and the power supply of the standby system control circuit is turned on.

[0175] Specifically, when the main system control circuit does not meet the preset conditions, it means that the main system control board jumps from the IDEL adjustment mode to the standby system. At this time, it is necessary to disconnect the power supply of the main system control circuit through the system cut-off switch and turn on the power supply of the standby system control circuit so that the standby system control circuit can work.

[0176] S1302. Detect in real time through the standby system control board whether a standby system control circuit is faulty.

[0177] It is understandable that during the operation of the standby system control circuit, the standby system control board will check the hardware circuit, the software / chip, and the output of the driver board in real time to determine whether the standby system control circuit is faulty. If the standby system control board detects that the standby system control circuit is faulty in real time, step S1303 is executed. If the standby system control board detects that the standby system control circuit is not faulty in real time, step S1305 is executed.

[0178] S1303, execute the fault process and disconnect the power supply of the standby system control circuit by cutting off the system switch.

[0179] Specifically, when a fault occurs in the standby system control circuit, the safety circuit needs to stop outputting 24V voltage to stop providing voltage to the standby system control board, and then stop outputting the static relay drive signal, switch the current mode of the standby system control board to ERR (fault), and disconnect the power supply of the standby system control circuit through the disconnect switch.

[0180] Optionally, in another embodiment of the present application, a specific implementation of the fault process is performed in step S1303, such as Fig.14 As shown, the following steps are included:

[0181] S1401. When a failure occurs in the standby system control circuit, the transmission function is stopped through the standby system control board, and the level of the dual system IO is set to a high level.

[0182] It is understandable that the standby control board continuously monitors the operating status of the standby control circuit, and when a fault signal or abnormal state (such as overcurrent, overtemperature, etc.) is detected, the fault handling process is immediately triggered. First, the communication interface will be closed: the communication between the standby control board and the main control board will be disconnected to stop data transmission. This can be achieved by setting the relevant registers or calling the corresponding interface shutdown command, and then programming the control register of the dual-system IO to set its level to a high level. Finally, after setting, read the IO status register to confirm that the level has been successfully set to a high level, so that by setting the IO level to a high level, other safety mechanisms (such as cutting off the power supply or activating the protection circuit) can be triggered to ensure that the control system remains safe in the event of a fault.

[0183] S1402. After the standby system control board sets a high level, the target square wave output is stopped to close the standby system status relay and each standby AC contactor in the standby system AC contact board.

[0184] It can be understood that after setting a high level through the standby system control board, the target square wave output is stopped. The main purpose is to turn off the standby system status relay and the standby system AC contactor. Specifically, the standby system control board is stopped from outputting the target square wave signal through control logic or register settings. This ensures that no further control signals are sent to the contactor. When the square wave signal stops, the control signal received by the standby system status relay disappears, causing the standby system status relay to disconnect, thereby cutting off the corresponding circuit. In the case where the standby system status relay is disconnected, the standby system AC contactor will also be cut off. This ensures that the standby system circuit is completely in a safe state and is no longer powered on, thereby preventing accidental startup of the equipment during a fault or maintenance by stopping the square wave output and cutting off the contactor to ensure safety.

[0185] Optionally, the high level setting and stopping of the square wave output can also be used as an indication of a fault state, making it convenient for monitoring system personnel to understand the equipment status in a timely manner.

[0186] S1304. Turn on the power supply of the main system control circuit by cutting off the system switch to ensure the normal operation of the three-phase asynchronous motor.

[0187] S1305. Obtain target electrical information of the target three-phase AC power output by the standby system AC contact board through the standby system motor voltage and current acquisition module, and receive operating parameters and synchronization signals sent by the main system control board.

[0188] It should be noted that when there is no fault in the standby system control circuit, it means that the standby system control circuit needs to work. At this time, the operating parameters in the standby system control circuit need to be consistent with the operating parameters in the main system control circuit in order to operate normally. Therefore, in addition to obtaining the target electrical information of the target three-phase AC power output by the standby system AC contact board through the standby system motor voltage and current acquisition module, the operating parameters and synchronization signals sent by the main system control board will also be received.

[0189] The electrical information includes the current value and voltage value of the target three-phase alternating current. The synchronization signal is used to ensure the coordination and data consistency between the standby system control circuit and the main system control circuit.

[0190] S1306. Synchronously output a target SVPWM waveform according to the operating parameters, the synchronization signal and the target electrical information.

[0191] Specifically, when the operating parameters, synchronization signals and target electrical information are obtained, the SVPWM (space vector pulse width modulation) waveform output by the main system control board is calculated according to the synchronization algorithm, and then the standby system control board maintains synchronization with the output of the target SVPWM waveform based on the SVPWM waveform output by the main system control board, thereby achieving redundancy and fault protection, and also ensuring that the main system waveform can continue to be output after the standby system control circuit upgrades the main system control circuit.

[0192] S1307. Output a target square wave through the standby system control board according to the target SVPWM control waveform, so as to drive the standby system status relay to control the standby system AC contact board to close each main AC contactor.

[0193] It can be understood that after the target SVPWM waveform is output, the target square wave, that is, a 10k square wave, needs to be output through the standby system control board according to the target SVPWM control waveform, so as to drive the standby system status relay to control the standby system AC contact board to close each main AC contactor, that is, to drive the standby system status relay to control each main AC contactor of the standby system AC contact board to fall, thereby achieving redundancy and reliability assurance.

[0194] S1105. Switch the self-check mode of the main system control board to the main system mode.

[0195] It can be understood that when the main system control circuit meets the preset conditions, the self-check mode (IDEL) of the main system control board is switched to the main system mode (MAS) to check the hardware circuit, software / chip and driver board output in real time.

[0196] S1106. Detect in real time through the main system control panel whether the main system control circuit is faulty.

[0197] It should be noted that in order for the three-phase asynchronous motor to maintain normal operation in real time, it is necessary to detect in real time through the main system control board whether the main system control circuit has a fault, so as to know whether it is necessary to switch to the backup system control circuit. Therefore, if the main system control circuit has a fault, it means that it is necessary to switch to the backup system control circuit, so execute step S1107.

[0198] Optionally, after executing step S1106, Fig.15 As shown, the following steps are also included:

[0199] S1501. If the main system control circuit does not fail, the main system motor voltage and current acquisition module is used to obtain electrical information of the three-phase AC power output by the main system AC contact plate.

[0200] It is understandable that when the main system control circuit does not fail, it means that the main system control circuit needs to be used to maintain the normal operation of the three-phase asynchronous motor, and in order to subsequently output the correct SVPWM waveform to improve the performance and efficiency of the motor drive, it is necessary to first obtain the electrical information of the three-phase AC output by the main system AC contact plate through the main system motor voltage and current acquisition module. Among them, the electrical information includes the current value and voltage value of the three-phase AC.

[0201] S1502. Output SVPWM waveform according to electrical information through the main system control board.

[0202] It can be understood that the SVPWM waveform is a space vector algorithm that divides the output into six sectors, but it is necessary to switch between sectors based on the current and voltage values ​​of the three-phase AC power. Therefore, based on the collected electrical information, the SVPWM algorithm is applied to generate a pulse width modulation signal suitable for the current load conditions. Among them, the error of the SVPWM waveform output by the main control board is less than 0.3%.

[0203] S1503. Output a square wave through the main system control board according to the SVPWM control waveform to drive the main system status relay to control the main system AC contact board to open each main AC contactor.

[0204] It can be understood that after obtaining the SVPWM control waveform, the output SVPWM waveform will be converted into a 10k square wave signal. The square wave signal is used to drive the main system status relay. These relays are responsible for controlling the switching state of the main AC contactor. Specifically, the high and low levels of the square wave signal trigger the closing or opening of the relay, thereby controlling the state of the AC contactor. When the main system status relay is closed, the main AC contactor will be activated, allowing AC power to flow into the three-phase asynchronous motor or other loads. During this process, the main system control board will continue to monitor the system status to ensure that the AC contactor works normally.

[0205] Optionally, if an abnormal situation (such as overload, short circuit, etc.) is detected, the main system control board can protect the system safety by adjusting the square wave output or immediately disconnecting the relay, and then switch to the standby system control board through the disconnect switch.

[0206] S1504, obtaining the operating parameters and synchronization signals of the main system control circuit through the main system control board, and sending the operating parameters and synchronization signals to the standby system control board, so that the standby system control board synchronously outputs the target SVPWM waveform according to the operating parameters and synchronization signals.

[0207] Specifically, the main system control board will monitor the operating status of the main system control circuit in real time, including key parameters such as current, voltage, and frequency, and generate synchronization signals when necessary to ensure that the standby system control board can receive the status information of the main system in a timely manner, and then send the operating parameters and synchronization signals to the standby system control board through appropriate communication interfaces (such as CAN, RS-485, Ethernet, etc.). After receiving the operating parameters and synchronization signals sent by the main system control board, the standby system control board will parse the received data, extract the information of the operating parameters and synchronization signals, and calculate and generate the target SVPWM waveform based on the received operating parameters and synchronization signals, thereby ensuring that when the main system control board switches to the standby system control board, the output SVPWM waveform is synchronized with the operating status of the main system, thereby achieving coordinated work of the system.

[0208] S1107, execute the fault process and disconnect the power supply of the main system control circuit by cutting off the system switch.

[0209] It is understandable that when a fault occurs in the main system control circuit, it is necessary to switch the main system mode of the main system control board to the fault mode, and the control system executes the fault process, and then disconnects the power supply of the main system control circuit through the system disconnection switch to facilitate the maintenance of the main system control circuit.

[0210] Optionally, in another embodiment of the present application, a specific implementation of the fault process is performed in step S1107, such as Fig.16 As shown, the following steps are included:

[0211] S1601. When a main system control circuit fails, the transmission function is stopped through the main system control board, and the level of the dual system IO is set to a high level.

[0212] It should be noted that the specific implementation of step S1601 and step S1401 are only different in the implementation objects, and the specific implementation methods are the same, so the specific implementation method of step S1601 can refer to the specific implementation method of the above-mentioned step S1401, which will not be repeated here.

[0213] S1602. After the main system control board sets a high level, the square wave output is stopped to close the main system status relay and each main AC contactor in the main system AC contact board.

[0214] It should be noted that the specific implementation of step S1602 and step S1402 are only different in the implementation objects, and the specific implementation methods are the same. Therefore, the specific implementation method of step S1602 can refer to the specific implementation method of the above-mentioned step S1402, which will not be repeated here.

[0215] S1108. Turn on the power supply of the standby system control circuit by cutting off the system switch to ensure the normal operation of the three-phase asynchronous motor.

[0216] The present application provides a control method for a three-phase asynchronous motor, which switches the current mode of the main system control board to the self-check mode after detecting that the control system is powered on, then obtains monitoring information through the main system control circuit, and reads all target monitoring information from the CF card, then determines whether there is target monitoring information matching the monitoring information in all target monitoring information, if there is target monitoring information matching the monitoring information in the target monitoring information, then determines whether the main system control circuit meets the preset conditions, if the main system control circuit meets the preset conditions, then switches the self-check mode of the main system control board to the main system mode, then detects in real time through the main system control board whether the main system control circuit fails, if the main system control circuit fails, executes the fault process, and disconnects the power supply of the main system control circuit through the system switch, and finally turns on the power supply of the standby system control circuit through the system switch, so as to enable the normal operation of the three-phase asynchronous motor. Thus, when the main system controls the motor normally, the standby system also runs and outputs synchronously, and can be switched to the main system control motor at any time to achieve seamless switching, thereby facilitating the repair of the faulty system.

[0217] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0218] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control system for a three-phase asynchronous motor, characterized in that: The control system comprises: a main system control circuit, a standby system control circuit and a system cut-off switch; The main system control circuit is composed of a main system control module, a main system power supply board, a main system drive board and a main system AC contact board; The standby system control circuit is composed of a standby system control module, a standby system power supply board, a standby system drive board and a standby system AC contact board; The external three-phase power supply is respectively connected to the three-phase input terminal of the main system power supply board and the three-phase input terminal of the standby system power supply board; The three-phase output end of the main system power supply board is connected to the three-phase input end of the main system drive board, and the output end of the main system power supply board is connected to the first input end of the main system control template; The input end of the main system drive board is connected to the first output end of the main system control template, and the three-phase output end of the main system drive board is connected to the three-phase input end of the main system AC contact board; The three-phase output terminals of the main system AC contact plate are respectively connected to the three-phase asynchronous motor and the three-phase input terminals of the main system control module; The third input terminal and the second output terminal of the main system control module are connected to the standby system control module, and the dual system IO interface of the main system control module is connected to the dual system IO interface of the standby system control module through the motherboard; The three-phase output end of the standby system power board is connected to the three-phase input end of the standby system drive board, and the output end of the standby system power board is connected to the first input end of the standby system control template; The input end of the standby system driving board is connected to the first output end of the standby system control template, and the three-phase output end of the standby system driving board is connected to the three-phase input end of the standby system AC contact board; The three-phase output terminals of the standby system AC contact plate are respectively connected to the three-phase input terminals of the three-phase asynchronous motor and the standby system control module; The system cut-off switch is connected to the second input terminal of the main system control module and the second input terminal of the standby system control module respectively; Among them, when the main system control circuit detects that the collected monitoring information does not match the stored monitoring information, the power supply of the main system control circuit is disconnected by the disconnection switch, and the power supply of the standby system control circuit is turned on to enable the normal operation of the three-phase asynchronous motor.

2. The control system according to claim 1, characterized in that: The main system control module includes: a main system control board, a main system CF card, a main system status indication module, a main system status switching relay, a main system voltage acquisition module, a main system three-phase half-bridge driver, a main system motor voltage and current acquisition module and a first resistor; The dual-system IO interface of the main system control board is connected to the dual-system IO interface of the standby system control module through the motherboard, the first input terminal and the first output terminal of the main system control board are connected to the main system CF card, the second input terminal of the main system control board is connected to the system cut-off switch, the third input terminal and the third output terminal of the main system control board are connected to the main system state switching relay, the fourth input terminal of the main system control board is connected to the output terminal of the main system voltage acquisition module, the fifth input terminal of the main system control board is connected to the output terminal of the main system motor voltage and current acquisition module, the first output terminal of the main system control board is connected to the input terminal of the main system state indication module, and the second output terminal of the main system control board is connected to the input terminal of the main system three-phase half-bridge drive; The first input terminal and the first output terminal of the main system state switching relay are connected to the standby system control module, and the second output terminal of the main system state switching relay is connected to the main system control board through the first resistor; The input end of the main system voltage acquisition module is connected to the output end of the main system power supply board; The output end of the main system three-phase half-bridge driver is connected to the input end of the main system driver board; The three-phase input terminal of the main system motor voltage and current acquisition module is connected to the three-phase asynchronous motor.

3. The control system according to claim 1, characterized in that: The main system power supply board is composed of a main three-phase transformer and a main three-phase rectifier bridge; The three-phase input end of the main three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the main three-phase transformer is connected to the three-phase input end of the main three-phase rectifier bridge; The three-phase output end of the main three-phase rectifier bridge is connected to the three-phase input end of the main system drive board, and the output end of the main three-phase rectifier bridge is connected to the first input end of the main system control template.

4. The control system according to claim 1, characterized in that: The main system driving board is a main three-phase bridge circuit, and the main three-phase bridge circuit is composed of three groups of main processing modules, and one group of the main processing modules includes two main transistors; wherein the collector of the first main transistor and the emitter of the second main transistor are used as the input end of the main processing module, and the emitter of the first main transistor and the collector of the second main transistor are used as the output end of the main processing module; the input end of each group of main processing modules is used as the three-phase input end of the main three-phase bridge circuit, and the output end of each group of main processing modules is used as the three-phase output end of the main three-phase bridge circuit; The three-phase input end of the main three-phase bridge circuit is connected to the three-phase output end of the main system power supply board, the input end of the main three-phase bridge circuit is connected to the first output end of the main system control template, and the three-phase output end of the main three-phase bridge circuit is connected to the three-phase input end of the main system AC contact board.

5. The control system according to claim 1, characterized in that: The main system AC contact plate is composed of three main AC contactors; wherein the input end of each main AC contactor is used as the three-phase input end of the main system AC contact plate, and the output end of each main AC contactor is used as the three-phase output end of the main system AC contact plate.

6. The control system according to claim 1, characterized in that: The standby system control module includes: a standby system control board, a standby system CF card, a standby system status indication module, a standby system status switching relay, a standby system voltage acquisition module, a standby system three-phase half-bridge driver, a standby system motor voltage and current acquisition module and a second resistor; The dual-system IO interface of the standby system control board is connected to the dual-system IO interface of the main system control module through the motherboard, the first input end and the first output end of the standby system control board are connected to the standby system CF card, the second input end of the standby system control board is connected to the system cut-off switch, the third input end and the third output end of the standby system control board are connected to the standby system status switching relay, the fourth input end of the standby system control board is connected to the output end of the standby system voltage acquisition module, the fifth input end of the standby system control board is connected to the output end of the standby system motor voltage and current acquisition module, the first output end of the standby system control board is connected to the input end of the standby system status indication module, and the second output end of the standby system control board is connected to the input end of the standby system three-phase half-bridge drive; The first input terminal and the first output terminal of the standby system status switching relay are connected to the standby system control module, and the second output terminal of the standby system status switching relay is connected to the standby system control board through the second resistor; The input end of the standby system voltage acquisition module is connected to the output end of the standby system power board; The output end of the standby system three-phase half-bridge driver is connected to the input end of the standby system driver board; The three-phase input terminal of the motor voltage and current acquisition module of the standby system is connected to the three-phase asynchronous motor.

7. The control system according to claim 1, characterized in that: The standby power supply board is composed of a standby three-phase transformer and a standby three-phase rectifier bridge; The three-phase input end of the three-phase transformer is connected to an external three-phase power supply, and the three-phase output end of the three-phase transformer is connected to the three-phase input end of the three-phase rectifier bridge; The three-phase output end of the standby three-phase rectifier bridge is connected to the three-phase input end of the standby system driving board, and the output end of the standby three-phase rectifier bridge is connected to the first input end of the standby system control template.

8. The control system according to claim 1, characterized in that: The standby system driving board is a standby three-phase bridge circuit, which is composed of three groups of standby processing modules, one group of which includes two standby transistors; wherein the collector of the first standby transistor and the emitter of the second standby transistor are used together as the input end of the standby processing module, and the emitter of the first standby transistor and the collector of the second standby transistor are used together as the output end of the standby processing module; the input end of each group of standby processing modules is used as the three-phase input end of the standby three-phase bridge circuit, and the output end of each group of standby processing modules is used as the three-phase output end of the standby three-phase bridge circuit; The three-phase input end of the standby three-phase bridge circuit is connected to the three-phase output end of the standby system power supply board, the input end of the standby three-phase bridge circuit is connected to the first output end of the standby system control template, and the three-phase output end of the standby three-phase bridge circuit is connected to the three-phase input end of the standby system AC contact board.

9. The control system according to claim 1, characterized in that: The standby AC contact plate is composed of three standby AC contactors; wherein the input end of each standby AC contactor is used as the three-phase input end of the standby AC contact plate, and the output end of each standby AC contactor is used as the three-phase output end of the standby AC contact plate.

10. A control method for a three-phase asynchronous motor, characterized in that: A control system applicable to a three-phase asynchronous motor according to any one of claims 1 to 9, wherein the control method comprises: When it is detected that the control system is powered on, the current mode of the main system control board is switched to a self-checking mode; Acquire monitoring information through the main system control circuit and read all target monitoring information from the CF card; Determine whether there is target monitoring information matching the monitoring information among all target monitoring information; If there is target monitoring information matching the monitoring information in the target monitoring information, determining whether the main system control circuit meets a preset condition; If the main system control circuit meets the preset conditions, the self-check mode of the main system control board is switched to the main system mode; Real-time detection of whether the main system control circuit is faulty by the main system control panel; If the main system control circuit fails, the fault process is executed and the power supply of the main system control circuit is disconnected by the disconnect switch; The power supply of the standby system control circuit is turned on by the system cut-off switch to enable the normal operation of the three-phase asynchronous motor.

11. The method according to claim 10, characterized in that After the main system control board is used to detect in real time whether the main system control circuit is faulty, the method further includes: If the main system control circuit does not fail, the electrical information of the three-phase AC power output by the main system AC contact plate is obtained through the main system motor voltage and current acquisition module; Outputting SVPWM waveform according to the electrical information through the main system control board; The main system control board outputs a square wave according to the SVPWM control waveform, so as to drive the main system state relay to control the main system AC contact board to open each main AC contactor; The operating parameters and synchronization signals of the main system control circuit are obtained through the main system control board, and the operating parameters and the synchronization signals are sent to the standby system control board, so that the standby system control board synchronously outputs the target SVPWM waveform according to the operating parameters and the synchronization signals.

12. The method according to any one of claims 10 to 11, characterized in that: After determining whether the main system control circuit meets the preset conditions, the method further includes: If it is determined that the main system control circuit does not meet the preset condition, the power supply of the main system control circuit is disconnected by the system cut-off switch, and the power supply of the standby system control circuit is turned on; Real-time detection of whether the standby system control circuit is faulty by the standby system control board; If the standby system control circuit fails, the fault process is executed, and the power supply of the standby system control circuit is disconnected by the disconnect switch; Turning on the power supply of the main system control circuit through the system cut-off switch to enable the normal operation of the three-phase asynchronous motor; If the standby system control circuit does not fail, the standby system motor voltage and current acquisition module obtains the target electrical information of the target three-phase AC output by the standby system AC contact board, and receives the operating parameters and synchronization signals sent by the main system control board; Synchronously outputting a target SVPWM waveform according to the operating parameters, the synchronization signal and the target electrical information; The standby system control board outputs a target square wave according to the target SVPWM control waveform, so as to drive the standby system status relay to control the standby system AC contact board to close each main AC contactor.

13. The method according to claim 10, characterized in that If the main system control circuit fails, the fault process is executed, including: When the main system control circuit fails, the transmission function is stopped through the main system control board, and the level of the dual system IO is set to a high level; After the main system control board sets a high level, the square wave output is stopped to close the main system status relay and each main AC contactor in the main system AC contact board.

14. The method according to claim 10, characterized in that If the standby system control circuit fails, the fault process is executed, including: When the standby system control circuit fails, the transmission function is stopped through the standby system control board, and the level of the dual system IO is set to a high level; After the standby system control board sets a high level, the target square wave is stopped from being output, so as to close the standby system status relay and each standby AC contactor in the standby system AC contact board.

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