The interpolation that is based on servo of total number word to control unit dominates algorithmic research

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Digital control is to accuse the signal that in making a system, issues is pulse signal. System of control of servo of digital type complete closed circuit is one kind has positional control and the feedback that speed controls two kinds of functions to control a system at the same time. Control what unit gives out to show emplacement value and position detect the poor value of the value is position error, the real position that it reflects always is lag is worth at appointing the position. Position error controls a quantity to control the whirl of feed electric machinery via speed serving as after processing, make real position also changes with this speed, and real position follows from beginning to end appoint the position, when showing emplacement stops change, real position is equal to appoint the position. The advantage of digital control system is, because use digital signal, interference rejection capability is strong; Applied system is simple, develop easily; Systematic stability is good. Traditional communication servo is system of typical speed closed circuit, servo driver receives voltage span to be from main control system - Ui ～ + the speed command signal of Ui. Voltage from - Ui changes + in the process of Ui, servo electric machinery can come true from invert most high speed rises to 0, rise to turning again next highest fast. But, servo of this kind of communication can realize the closed-loop control to speed only, return the closed-loop control that cannot realize contrapuntal buy directly. Want to realize the closed-loop control of contrapuntal buy, ring of a position must be made between servo electric machinery and control system. Motion controls algorithm this position annulus controls unit to finish by digital servo. The function of positional annulus is implementation position closed-loop control, inputting pulse is pulse of a differential actually, need a value by what measure pulse actually what good pulse gives set to be answered with feedback beforehand namely, measure the position and dynamic error according to giving emplacement to mix namely, the speed that computation asks to want to achieve is referenced, offer its servo driving unit. If the graph shows servo of amount to word 1 times to control unit motion to control algorithmic block diagram: Graph the motion with unit control of 1 number servo controls servo of algorithmic and whole number to control a system is to lean real time monitoring and adjust speed parameter, namely the input pulse of servo driving unit will control servo motor. And athletic control algorithm uses calculation this speed parameter. By the graph 1, can seeing speed parameter is give by the position, measure pulse and feedback error these 3 parameter will decide. Additional, the position that Kp of 5 gain parameter, Ki, Kd, Kov and Kvff defined different control pattern to fall controls an operation. Scale gain Kp can produce an output Op, any control mode should use scale gain Kp, it becomes direct ratio with feedback error E, namely: The summation of the output Oi that Ki of integral gain of E (1) of × of Op ＝ Kp produces and error E becomes direct ratio, namely because E(2) of Δ of × of Oi ＝ KI is integral gain adjustment is caused easily exceed adjusting range, so commonly only systematic work is in constant the ability below the circumstance that career position quickens slow perhaps uses it. Od is by differential gain Kd computation is reached, it reflected the change of feedback error pulse. Namely E(3) of Δ of × of Od ＝ Kd is differential gain adjustment can produce a flowing response, but the meeting when gain is taller produces vibration. The output Oov that Kov of speed output gain produces is change proportionate with what measure positional Pm, it can enhance damp character of the system. Namely the output Ovff that Kvff of gain of the make a present of before speed of Pm (4) of Δ of × of Oov ＝ Kov produces is change proportionate with what give emplacement Pd. Namely the implementation control flow chart with algorithmic control of Pd (5) of Δ of × of Ovff ＝ Kvff controls algorithmic analysis according to afore-mentioned motion, use C language design, staff pilot of motion of complete closed circuit tests a program. If specific control flow chart pursues 2. Graph 2 control flow chart the stability to enhance a system, positional increment is adopted be restricted a processing, because positional increment passes to go against the stability of safe operation and system greatly, and output is restricted a processing it is to be when positional set value is choppy, prevent computation to may be more than the limit of actuator as a result. The program is debugged the process is debugged in the program in, 3 parameter want to adjust accurately: The Kp parameter of · scale link affects the sensitivity of systematic movement and precision of pilot stable state, the cost that increases Kp is helpful for reducing stable state error, raise the control precision of linear electric machinery, but the accretion as Kp, criterion the stable state error that the Ki parameter that the system will not stabilize link of integral of; · uses at controlling a system, if Ki is installed too smally, oscillation frequency grow in quantity. If be installed too greatly, go against the stable state error that eliminates a system, obtain taller control precision hard; · must slant to Kd setting big or slant hour, make of the system exceed tone to increase, adjust time lengthen, go against systematic stability. Additional, still can control open loop and closed-loop control union rises use, go up in foundation of closed-loop control loop namely, add an input signal (give or disturb) access of suitable make a present of, execute to this signal strengthen or compensate. In order to achieve accurate control result. As a result of the relation of length, did not introduce in detail here. Last word article controls unit interpolation to controlled algorithm to undertake elaborate and be analyticed to servo of total number word, consider and the interpolation that process designing realized a kind to be based on servo of total number word newly to control unit controls algorithm. Because use method of software process designing to realize this interpolation to control algorithm, parameter change is very quick, can win wide application consequently. This algorithm applies already successfully in the project, the accord that gets a client reputably, reduced labor intensity of the worker, improved work efficiency. CNC Milling CNC Machining