Due to the influence of low-frequency resonance characteristics of stepper motors, the control efficiency and accuracy of the previously designed network dangerous data controller are low. Therefore, the subdivision controller of network dangerous data is designed. The current fluctuation will occur when the network data is transmitted to the stepper motor in the controller. The A4988 subdivision chip subdivides the current. The power module provides voltage conversion for the control of A4988 subdivision chip, and maintains the normal operation of subdivision chip under standard voltage. Data filtering module includes transceiver circuit and classification circuit. The transceiver circuit receives the network data controlled by A4988 subdivision chip. The classification circuit filters out the dangerous data and transmits it to users through transceiver circuit. The software builds the subdivision control model of stepper motor to network data, and realizes the efficient and precise control of the controller. The experimental results show that the designed controller has high control efficiency and accuracy. In recent years, the emergence of stepping motors has accelerated the development of automation. The combination of network and automation brings a new dawn for the continuous progress of technology in various fields. Stepping motors also play a very important role in network data control. There are many dangerous data in the network.
In order to improve network security, scientific research organizations have integrated many control methods for stepping motors. However, due to the influence of low-frequency resonance characteristics of stepping motors, the previous control methods can not accurately control the network dangerous data, and the control efficiency is also low [2]. Subdivision is a control method that can effectively improve the low-frequency resonance characteristics of stepper motors. Therefore, a subdivision controller for network dangerous data is designed. There are three working modes of subdivision chips: current hysteresis method, switching frequency method and constant frequency pulse width method [3]. The A4988 subdivision chip produced by a company is selected.
The chip is small in size and has a subdivision mode as high as possible. Its control interface is simple and can provide a variety of control modes for the operation of stepper motors. The output current of A4988 subdivision chip is adjustable, which enhances the flexibility of network dangerous data subdivision controller to a certain extent and improves the control accuracy effectively. Fig. 1 is the internal circuit diagram of A4988 subdivision chip. As can be seen from Figure 1, A4988 subdivision chip has the function of automatic current attenuation test. For abnormal network data current, it can provide circuit dormancy, current tracking and circuit crossover operations, and has protection modes such as power grounding and logical short circuit. The power module is responsible for providing voltage conversion for the control of A4988 subdivision chip, thermostatic element ensuring that the subdivision chip can work normally under standard voltage [4?5]. The standard voltage of A4988 subdivision chip is 6V, 5V and 3.3V in order. The 6V voltage can be supplied directly by stepper motor. The 5V and 3.
3V voltage need power module to convert the 6V voltage of stepper motor, and then supply to A4988 subdivision chip. Figure 2 is a 6V? 5V conversion circuit diagram, and Figure 3 is a 5V? 3.
3V conversion circuit diagram. From Figure 2 and Figure 3, it can be seen that the design of the conversion circuit of the power module is relatively simple and the size is small. Both circuits are designed with a power chip based on Sequence Packet Switching Protocol (SPX). This power chip can convert voltage and power quickly without heating up the circuit components, and can maintain the stability of the network dangerous data subdivision controller. Data filtering module includes transceiver circuit and classification circuit [6]. The transceiver circuit receives the network data processed by the A4988 subdivision chip, and the classification circuit filters out the dangerous data, and then transmits it to the user through the transceiver circuit. The transceiver circuit and the classification circuit are shown in figs. 4 and 5. From figs. 4 and 5, we can see that the essence of transceiver circuit is the organic combination of antenna and crystal oscillator circuit, which controls the different impedance before and after operation according to the A4988 subdivision chip, and accurately transmits and receives network data. The transceiver circuit is also equipped with a humidity control switch and a display to adjust the working mode of the circuit and filter and display the network data. The voltage balance model of stepping motor can be simplified to an equivalent circuit model, as shown in Figure 6.
Figures 7-9 show the control efficiency comparison of the three controllers in three types of networks. From figs. 7 to 9, it is shown that in star network, the control efficiency of the controller is the highest, ranging from 98.8% to 99.5%, and the control efficiency is very stable. The control efficiency of cross-flow chopper controller is the lowest, its control efficiency is between 95.6% and 98.7%, and the stability of control efficiency is the worst. The control efficiency of single-phase power supply controller is more moderate.
In the ring network, the control efficiency of the cross-current chopper controller and the single-phase power supply controller is obviously reduced. The control efficiency of this controller is still between 98.2% and 99.3%, which is obviously higher than that of the other two controllers. In the bus network, the control efficiency of the three controllers is obviously different, which may be caused by the poor security performance of the bus network. Among them, the control efficiency of the controller in this paper is still significantly higher than that of the other two controllers. In summary, the controller in this paper has high control efficiency. The control accuracy of the three controllers for star network, ring network and bus network is expressed by the average false alarm ratio of dangerous data set. The lower the ratio, the higher the control accuracy of the controllers. The experimental results are shown in Table 1. The design goal of this paper is to improve the control efficiency and accuracy of the controller for network dangerous data. Subdivision is a control method that continuously refines something according to a special way, and then obtains smooth curve. It can enhance the robustness and positioning accuracy of stepper motor, and make the stepper motor obtain higher resolution. Therefore, this paper designs a network dangerous data subdivision controller, which is based on stepper motor control hardware, focusing on the subdivision chip, data filtering module and power module. The experiment compares the controller with single-phase power supply controller and cross-current chopper controller. The experimental results show that the controller has high control efficiency and accuracy in star network, ring network and bus network.