Abstract: the servo drive products have been widely used in machine tool industry, CNC processing industry. This paper presents a new generation of servo the direction of development, and detailed how a new generation of servo product characteristics, puts forward a new generation of products because its function and characteristics of the servo will widely application. The article also introduces LuoSheng enterprise Co., LTD. Tianjin, introduced intelligent servo driver ELMO and precision direct drive motor yokogawa DD motor.
Key word: DD motor, Elmo servo, precise, intelligence
In recent years, domestic industrial automation field present a rapid development trend, the foreign advanced technology and accessible introduction to get promotion, among them as a driver of important representative products of servo has been the masses of users to accept, in the machine in the innovation process played a crucial role. Precise driving effect and intelligent motion control through the servo products can perfect realization of automatic machine efficiency, the two aspects of development has become an important indicator of the servo.
1 servo system is introduced
Servo drive technology is an important part of the numerical control technology. Combined with the numerical control device, servo system static and dynamic characteristics of the machine tool directly influence displacement speed, precision and processing precision. Now, dc servo system is exchange digital servo system substituted; Servo motor position, speed and the current loop has realized digital; And used the new control theory, realized from the influence of mechanical load change high-speed response system.
Its main new development of technology are:
A. feedforward control technology. The past servo system, the detector signal and position is instructions to position loop gain signal is multiplied by poor
As speed instructions. This kind of control mode there is always tracking lag error, this makes the processing and arc corner when processing precision worse. The so-called feed-forward control, which is in the original control system with speed control mode of instruction, so that make a servo system tracking lag error greatly decreased.
B. mechanical static friction of nonlinear control technology. For some with larger static friction numerical control machine tool, the new digital servo system has compensation machine drive system static friction of nonlinear control function.
C. servo system of the position loop and speed loop (including current loop) is using software control, such as digital mediation and vector control, etc. To adapt to the different type of machine tools, different precision and different speed to art, add, slow performance adjustment in advance.
D. using high resolution position detection device. Such as high resolution pulse coder, with microprocessors composition the breakdown of the circuit, making the resolution greatly improve, incremental position detection for 10000 p/r (pulse several/every turn) above; Absolute position detection for 1000000 p/r above.
E. compensation technology obtained the development and the application. Modern numerical control system has compensation function, can perform a variety of compensation of servo system, such as the ball screw pitch error compensation, tooth side clearance compensation, axial movement error compensation, space error compensation and thermal deformation compensation, etc.
2 a new generation of precise servo products
The so-called precision, it is to show through the servo drive after implementation effect and goal setting to the same degree is high, the control precision. To reach such results need to be in actuators (motor) and driving system (driver) do pointed design and manufacturing.
Japan is the DDM yokogawa Co. products have such characteristics of the very typical product.
The following three aspects of it introduces DD motor
First of all, clearance error is eliminated.
Common transmission mechanism with deceleration machine, coupling and gear, belt or ball screw, etc of the intermediate links, and the clearance error is cannot avoid, particularly for the long run time by the mechanical wear is unable to compensate. DD motor just can be a very good solve the above problem, because DD direct drive of installation (figure 2), the error was reduced to at least; And it also can at any time of the servo characteristics error correction, to achieve optimal control precision.
Second, high resolution and high precision. DYNASERVDD motor matching of high-resolution encoder, DM1B-045 resolution for 655360 PPR (DM-A series of up to 4096000 PPR), electric control precision, has more than ordinary servo control accuracy one order of magnitude. The production quite precise and eventually accuracy control of general can reach two seconds or less.
Third, high rigidity, compact structure, high efficiency. DD motor rigidity is very strong, and load characteristics with hard, for its drive requirements are higher. The latest model of DYNASERV drive can provide online gain commissioning and resonant filter. Unique design not only reduce hollow motor's own inertia, and to provide the customer more installation forms. After the combination of mechanical structure will be more compact, use efficiency is highest other ways.
The relative speed DD motor is lower, the rated speed in basic RPM 60 ~ 240 RPM between, but here is the speed in the final of the turntable speed, relative than ordinary servo + reducer framework, the speed in the final is also very has the advantage. At the same time in keeping the speed DD motor maintaining high output torque, due to the permanent magnet stator, so in the rated speed in the motor torque output yokogawa DD curve can keep smooth linear characteristics.
Yokogawa's GIII driver adopted the I-PD control mode, the bandwidth of the same current loop, the I-PD control GIII drive up to 10 Hz bandwidth position loop, and the traditional PID control way in, reducing the speed of 2.5 times the bandwidth. The characteristics of the motor to high rigidity (position bandwidth).
In application, yokogawa DDM products are in the most advanced position, involving fields have a printer industry, LCD production line pressure sensitive, DVD/CVD production equipment, IC testing equipment, semiconductor manufacturing equipment, electronic manufacturing equipment industry machinery fields.
Self-adhesive label printing machines using flat pressure type structure design, mainly complete process: send paper, printing (second overprint), pressure protruding, hot stamping, cutting or accept book, counting. Printing speed of 60-180 / minutes. A printing determination value < 0.03, secondary overprint determination value < 0.035. (statistics) values. DD motor used to drive the main drag of the roller, the control principle chart 5 depending, 1 times when printing uniaxial controller
SPC007 DD motor control the length and speed walking, and color of the printing plate; Secondary overprint, color standard sensor scans Mark point, notice to chase Mark mode control SPC007 DD movement, and the printing plate f. Walking distance and velocity can be set by up front thumbwheel switches or man-machine interface to complete. Older type coil, save manpower, especially to adjustment problems, entirely by the controller to complete. Avoid the mechanical error caused by mechanical adjusting work makes regular, improve working efficiency. And simple maintenance, equipment safety.
Yokogawa DD motor's largest industry application is LCD, semiconductor shut industry, figure 6 in the application of the machine is HuaPian, figure 7 is the application of FenJianJi in IC, also use the DD motor of high precision, high rigidity and directly connected simple structure, easy maintenance and long service life precision characteristics, at present in the larger market.
3 a new generation of intelligent servo products
Intelligent refers to products can do intelligent way of servo drive and control. The driver drive ability, the control effect, programming and development and upper control system and information and communication opening degree is measured the driver of the intelligent product basic indicators.
From analog silicon-controlled driving circuit of simple module to lap now all digital communication drive, short 10 years of time drive innovation never stops. Through the introduction of the driver let Israel elmo domestic more people familiar with the world's most advanced development direction.
Elmo drive in the design of the "active" emphasis on the concept, the independent development of chip circuits, make the whole process remains in the smooth transition. Compared with the traditional RC "passive" conversion way, start-up and shut off the current shock and losses will be reduced greatly, can achieve very low EMI. Elmo produces all sorts of drive (with MOSFET or IGBT drive), all can achieve a rapid and effective power conversion, and energy consumption of no more than 3% loss. In energy consumption Elmo the company put forward in the concept of heat energy management, emphasis on energy consumption is low loss at the same time, heat can also get effective release. Its unique ceramics mounted cooling technology, which can ensure the quantity of heat of 100% is derived.
In order to be fast, powerful fusion motors and drives, Elmo company launched SimplIQ technology (FIG 8), has a variety of feedback choose programming ability, and the standard signal monitoring technology, excellent motion control technology, simplify control process, the machine in an ideal job. Elmo drive with a unique senior position control functions including point-to-point motion, PT (position schedule), PVT (position speed time), ECAM (electronic CAM), position, follow, dual-circuits input pulses, fast events capture, rapid output is [OC], events capture type interrupt, events triggered programming, etc. At the same time in the senior filter and gain reservation mode Elmo drive is also unique design, including the state of the speed and supervise the current gain setting, speed position PIP control, automatic rectifier modulation, automatic motor phase sort, etc. Communication support RS-232, CANopenDS-301, DS-402.
Elmo controller Maestro is based on a network of multi-axis motion controller and monitor (FIG 9), through its own intelligent with Elmo drives use, can complete many complex multi-axis motion control. With Masetro and SimpleIQ drive constructed movement control network is based on distributed motion control network structure. At the same time support synchronous movement control, motion control, more order axis motion records and analysis tools, the multiaxial application development system. Through the direct access Ethernet finish the axis of the adjustment, monitoring and common analysis.
In space, medical and so on packing, industrial machinery, Elmo drive due to their own characteristics, has also been widely used.
Two Elmo drive connected auxiliary feedback from the shaft with spindle, complete ECAM function, need not controller, it can control the movement of the need to complete.
For coiling machine of application, of which a follow encoder, complete ECAM function, the other two sets drives have a as the main, the other a as from, complete ECAM function, so do not need the controller can be completed coiling machine movement control.
Accurate positioning and intelligent control will further to the direction of development, the structure of the electromechanical integration revolution and drive and control the mutual infiltration in the next few years will be leading the market new trend. Tianjin LuoSheng enterprise Co., LTD. Has been committed to the development direction, promote the domestic industry motion control advanced advanced product introduction and promotion, gradually domestic will also be part of the product (motor driver) close to the international advanced level, the field has a place in the world.