1 Introduction: Stepper motors are commonly used as servo control devices, and their running accuracy is a key concern for engineers. These motors often operate in open-loop systems without position sensing or feedback, which means the accuracy of their movement depends mainly on the motor itself and the mechanical system. Designers typically focus on step angle accuracy to ensure better performance. However, this is only critical in low-load applications. In high-load scenarios, the misalignment angle may have a greater impact than the step angle error, yet it's often overlooked. This article aims to clarify these concepts and provide insights into how misalignment angles affect the performance of stepper motor systems. The offset angle refers to the angular displacement of the rotor when a load torque is applied. When no load is present, the rotor remains at a stable equilibrium point. As torque increases, the rotor shifts, creating an offset angle. This angle depends on factors such as the energization waveform, load torque magnitude, and the motor’s torque-angle characteristics. While precise calculation can be complex, approximate analysis is often sufficient for practical applications. It is common to assume a sine wave relationship between torque and angle, which simplifies the modeling of motor behavior under different loads. 2 Corner Loss: In control systems, the stepping motor acts as an actuator that drives the controlled object through a transmission mechanism. The load torque generated by the system causes a misalignment angle, which can lead to angular loss during operation. For example, in a CNC lathe, the load torque varies depending on the cutting depth, affecting the motor’s ability to maintain accurate positioning. When the motor moves forward and then reverses, the angular loss doubles due to the change in direction and the residual offset angle. This phenomenon is particularly significant in high-precision applications where even small losses can result in noticeable errors. 3 Relationship Between Angular Misalignment and Energization Mode: The amount of angular misalignment is influenced by the load and the energization method. While the maximum misalignment angle is not directly related to the mode of energization, the number of energized states affects the overall precision. For instance, a three-phase hybrid motor operating in half-step mode has more energized states, which increases the potential for angular loss. Understanding this relationship is crucial for optimizing motor performance in various applications. 4 Limitations of Microstep Drive Technology: Although microstepping improves smoothness and reduces vibration, it also increases the risk of angular loss in open-loop systems. This is because microstepping divides the step angle into smaller increments, increasing the number of energized states. If the load torque is not properly managed, the cumulative effect of small misalignments can lead to significant positioning errors. Therefore, while microstepping is beneficial for certain applications, it requires careful design and control to maintain accuracy in open-loop configurations. 5 Conclusion: Microstep drive technology offers advantages in terms of smooth operation and resolution, but its effectiveness in open-loop systems is limited by the potential for angular loss. Proper design, including appropriate load management and energization strategies, is essential to ensure reliable and accurate performance. In applications with minimal load or high precision requirements, alternative approaches may be more suitable to avoid the limitations associated with open-loop control. custom cnc milling parts aluminum,cnc milling parts,cnc machining parts aluminum Dongguan Yingxin Technology Co., Ltd. , https://www.dgyingxintech.com
