Optimization control method of flexible connection master and slave motors

Abstract

The invention discloses an optimal control method for a flexible connection master-slave motor, and the method comprises the steps: setting a master machine and a slave machine to work in a speed mode, and enabling the speed set values of the master machine and the slave machine to be the same; the slave machine adds a speed deviation delta V on the basis of a speed set value; and connecting the torque set value of the host to the torque amplitude limit of the slave. According to the method, the defects of traditional flexible connection master and slave motor control are overcome, the flexible connection master and slave motors are controlled in a speed deviation and torque amplitude limiting mode, uniform distribution of torque of the master and slave motors is guaranteed, protection during disconnection is achieved, and motor galloping accidents are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular to an optimization control method for soft-connected master and slave motors. Background Art

[0002] In the actual application of motor inverter control, due to process requirements or inverter capacity limitations, a transmission device is often used that is driven by two or more motors. For example: The master and slave motors are hard-connected, such as gears, coaxial, etc. A soft connection is used between the master and slave motors, such as coupling produced by flexible materials such as belts and ropes. In these two connection modes, the master and slave motors need to have the same running speed and ensure uniform distribution of motor torque. To this end, it is necessary to implement speed and torque distribution control requirements on the frequency converter controlled by the motor. This application of the frequency converter is called master-slave control application.

[0003] For master-slave control applications, direct torque distribution is usually used on the inverter to achieve: In direct torque working mode, the master works in speed mode and the slave works in torque mode. For example, the Siemens S120 variable frequency control mode is as follows: 1. In the START debugging software, select the master speed working mode P1300=20or 21, and select the slave torque working mode P1300=22 or 23; 2. Then select the master's torque setting value r079 at the slave's torque setting value P1503; 3. Connect the control word command source of the slave to the control word of the host to obtain the same startup logic, ensure simultaneous startup and stop of the master and slave devices, and implement fault protection.

[0004] At present, most soft-connected master-slave motors are still controlled by direct torque distribution, which has the following problems: 1. The belt cannot be quickly tightened to output effective torque during startup, which affects the timeliness and accuracy of production control and induces system oscillation.

[0005] 2. When the connection is disconnected, the slave motor is in torque control mode, which may cause accidents such as runaway when there is no load. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide an optimization control method for soft-connected master-slave motors. The method overcomes the defects of traditional soft-connected master-slave motor control, controls the soft-connected master-slave motors by speed deviation and torque limiting, ensures uniform distribution of the master-slave motor torque, realizes protection when the connection is disconnected, and avoids motor runaway accidents.

[0007] In order to solve the above technical problems, the optimization control method of soft-connected master and slave motors of the present invention comprises the following steps: Step 1: Set the master and slave to work in speed mode, and the speed setting values ​​of the master and slave are the same; Step 2: The slave adds a speed deviation ΔV based on the speed setting value; Step 3: Connect the master's torque setting value to the slave's torque limit.

[0008] Furthermore, in step 2, the speed deviation ΔV is equal to ±5-10% of the speed setting value.

[0009] Further, in step 2, when the master and slave are working in scheme A, the speed setting value V of the slave is set. 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; when the master and slave are working in scheme B, set the speed setting value V of the slave 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme C, set the slave's speed setting value V 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme D, set the slave's speed setting value V 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; Among them, Plan A is that the slave is in front, the master is in the back and they run clockwise; Plan B is that the master is in front, the slave is in the back and they run clockwise; Plan C is that the slave is in front, the master is in the back and they run counterclockwise; Plan D is that the master is in front, the slave is in the back and they run counterclockwise.

[0010] Since the optimization control method of the soft-connected master-slave motor of the present invention adopts the above technical solution, that is, the method sets the master and slave to work in speed mode, the speed setting values ​​of the master and slave are the same; the slave adds a speed deviation ΔV on the basis of the speed setting value; the torque setting value of the master is connected to the torque limit of the slave. This method overcomes the defects of traditional soft-connected master-slave motor control, and controls the soft-connected master-slave motor by speed deviation and torque limit, ensuring the uniform distribution of the master and slave motor torque, realizing protection when the connection is disconnected, and avoiding motor runaway accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments: Figure 1 This is the working diagram of the master-slave motor A scheme in this method; Figure 2 This is the working diagram of the master-slave motor scheme B in this method; Figure 3 This is the working diagram of the master-slave motor C scheme in this method; Figure 4 This is the working diagram of the master-slave motor scheme D in this method. DETAILED DESCRIPTION

[0012] The optimization control method of the soft-connected master and slave motors of the present invention comprises the following steps: Step 1: Set the master and slave to work in speed mode, and the speed setting values ​​of the master and slave are the same; Step 2: The slave adds a speed deviation ΔV based on the speed setting value; Step 3: Connect the master's torque setting value to the slave's torque limit.

[0013] Preferably, in step 2, the speed deviation ΔV is equal to ±5-10% of the speed setting value.

[0014] Preferably, Figures 1 to 4 As shown, in step 2, when the master and slave work in scheme A, the speed setting value V of the slave is set 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; when the master and slave are working in scheme B, set the speed setting value V of the slave 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme C, set the slave's speed setting value V 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme D, set the slave's speed setting value V 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; Among them, Plan A is that the slave is in front, the master is in the back and they run clockwise; Plan B is that the master is in front, the slave is in the back and they run clockwise; Plan C is that the slave is in front, the master is in the back and they run counterclockwise; Plan D is that the master is in front, the slave is in the back and they run counterclockwise.

[0015] Through the above settings, due to the existence of speed deviation, the soft material connecting the master and slave motors is quickly tightened, the speed loop of the slave is saturated, and the output torque is limited by the torque limit, thereby ensuring that the torque of the slave follows the torque of the master; the speed of the slave is pulled by the connection and is the same as the speed of the master. When a belt break occurs, the master and slave motors work in their respective speed loop modes, and the runaway phenomenon will not occur. This control method uses speed deviation and torque limiting to control the soft-connected master and slave motors, such as belts and ropes. The speed deviation and torque limiting method is mainly used in the soft connection between the master and slave motors. Due to the coupling relationship generated by flexible materials, the master and slave motors need to have the same operating speed, while ensuring the uniform distribution of the motor torque and providing protection to prevent disconnection.

[0016] When this control method is applied, after the motor is started, due to the existence of speed deviation, the flexible material connecting the master and slave motors is quickly tightened, the speed loop of the slave is saturated, and the output torque is limited by the torque limit, thereby ensuring that the torque of the slave follows the torque of the master; the speed of the slave is pulled by the flexible material connection and is the same as the speed of the master. When disconnection occurs, the master and slave motors work in their respective speed loop modes, and the flying phenomenon will not occur.

[0017] The characteristic of this control method is that the speed loops of the master and slave are both activated at the moment of starting, and the tension is established relatively smoothly, avoiding oscillation of the system, which not only ensures the distribution of speed and torque, but also protects the system.

Claims

1. An optimization control method for soft-connected master and slave motors, characterized in that The steps include: Step 1: Set the master and slave to work in speed mode, and the speed setting values ​​of the master and slave are the same; Step 2: The slave adds a speed deviation ΔV based on the speed setting value; Step 3: Connect the master's torque setting value to the slave's torque limit.

2. The optimization control method of soft-connected master-slave motors according to claim 1, characterized in that: In step 2, the speed deviation ΔV is equal to ±5-10% of the speed setting value.

3. The optimization control method of soft-connected master-slave motors according to claim 1 or 2, characterized in that: In step 2, when the master and slave are working in scheme A, the speed setting value V of the slave is set. 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; when the master and slave are working in scheme B, set the speed setting value V of the slave 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme C, set the slave's speed setting value V 从 Leading the host speed setting value V 主 , that is, V 从 =V 主 +ΔV; when the master and slave work in scheme D, set the slave's speed setting value V 从 The speed setting value V of the lagging host 主 , that is, V 从 =V 主 -ΔV; Among them, Plan A is that the slave is in front, the master is in the back and they run clockwise; Plan B is that the master is in front, the slave is in the back and they run clockwise; Plan C is that the slave is in front, the master is in the back and they run counterclockwise; Plan D is that the master is in front, the slave is in the back and they run counterclockwise.

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