Servo Technology and New Trends
Modern AC servo system, has gone from analog to digital transition, digital control loops have become ubiquitous, such as commutation, current, speed and position control; using new power semiconductor devices, high-performance DSP plus FPGA, and servo-specific modules (For example, IR launched a dedicated servo control engine) is not surprising. International manufacturers of servo products every five years will be updating the new power devices or modules will be updated every 2.5 years 2 to a new software algorithm is ever-changing, short product life cycles are getting shorter. Summary of domestic and foreign manufacturers of servo technology roadmap and product line, combined with changes in market demand, you can see some of the latest trends following: High efficiency Although the work in this area has long been going on, but still need to continue to strengthen. Including the motor itself, the performance of permanent magnetic materials, such as high efficiency improvements and a better design of the magnet mounting structure also includes a high efficiency of the drive system, including the optimization of inverter driver circuit to optimize acceleration and deceleration movement, regenerative braking and energy feedback, and better cooling methods. Direct drive Including the use of servo direct drive turntable disc drive motor and linear servo linear motor drive, due to the elimination of the intermediate transmission error, enabling high-speed and high positioning accuracy. Easy to change the shape of the linear motor so that the various devices can be characterized using the linear straight line mechanism to achieve miniaturization and weight reduction. High-speed, high-precision, high performance Using more accurate encoder (million pulses per revolution level), higher sampling accuracy and data bits, faster DSP, no cogging, high-performance rotary motors, linear motors, as well as adaptive, artificial intelligence and other modern control strategy, and constantly improve the indicators of the servo system. Integration and integration Motor, feedback, control, drive, communication has become a development direction of vertical integration the current low-power servo system. Sometimes we call this integrated motor drivers and communications called intelligent motor (Smart Motor), sometimes we have to integrate motion control and communication drive called intelligent servo drives. Motors, drives and control integration enables three from design, manufacturing to operation and maintenance are integrated more closely. However, this approach faces greater technical challenges (such as reliability) challenges and engineers habits, it is difficult to become mainstream in the entire servo market is a small distinctive parts. Universal Universal has a lot of drive configuration parameters and rich menu functions, user-friendly conditions without changing the hardware configuration and easily set to V / F control, open loop speed sensorless vector control, closed-loop flux vector control of permanent magnet five works brushless AC servo motor control and regeneration unit, etc., suitable for various occasions, can drive different types of motors, such as induction motors, permanent magnet synchronous motors, brushless DC motors, stepper motors, can also adapt to different sensor types or no position sensor. You can use the configuration of the motor itself constitute a semi-closed loop feedback control system may be configured high-precision closed-loop control system via an interface with external position or velocity or torque sensors. Intelligent Modern AC servo drives with parameter memory, fault diagnosis and analysis capabilities, the vast majority of imports drives are equipped with load inertia measurement and automatic gain adjustment function, and some can automatically identify the motor parameters, automatic measuring encoder zero, while others can automatically suppress vibration. The electronic gear, electronic cam, synchronization tracking, and other control functions and the interpolated motion driven together, the servo user, provide a better experience. Network and modular The fieldbus and industrial Ethernet technology, and even wireless networking technology is integrated into the servo drive which has become a common practice in Europe and the United States manufacturers. Important direction and focus of the various competing bus standard LAN modern industrial development is how to adapt to high-performance motion control for real-time data transmission, reliability, synchronization requirements. With the rise in domestic demand for large-scale distributed control device, the successful development of high-end CNC system, networked digital servo development has become imperative. The modular approach not only refers to the combination between the servo drive module, power module, regenerative braking modules, communication modules, and refers to the servo drives internal software and hardware modularity and reusability. From troubleshooting to predictive maintenance With the continuous development of machine safety standards, the traditional fault diagnosis and protection technology (when problems occur to determine the cause and take measures to avoid failure magnify) have become obsolete, the latest products and embedded predictive maintenance technology, makes it through the Internet in a timely manner understanding of the dynamic trend of the important technical parameters, and to take preventive measures. For example: Focus on current increases, the peak current assessment, the housing or the core temperature monitoring temperature sensors, and any distortion of the current waveform alert occurs when the load changes. Specialization and diversification Although there are universal servo product line on the market, but for certain applications specially designed and manufactured servo system abound. Using different magnetic properties, electrical different shapes, different surface bonding structure (SPM) and embedded permanent magnet (IPM) rotor structure appears split core structure technology used in Japan to make permanent magnet brushless servo motor production achieve a high efficiency, high-volume and automated, and cause domestic manufacturers research. Miniaturization and large-scale Whether it is a permanent magnet brushless servo motors or stepper motors are actively to the development of a smaller size, such 20,28,35mm outer diameter; models while also developing more power and size, has seen 500KW permanent magnet servo motor appears. Reflects the tendency to polarize development.