Summary: Analysed servo of two kinds of communication to control theory, designed digital communication servo to control module with this. This module handles chip to be core with high-powered digital signal, in the system but number of composition of process designing parts of an apparatus is inputted / output circuit. This module has interference rejection capacity strong, dependability tall, function / price comparing is tall, modular wait for a characteristic. Contemporary communication servo is to pilot requirement: Answer fast, precision tall, torsion is pulsatile small. The high-powered control that realizes torsion of AC motor instantaneous is the crucial factor that satisfies these requirements. Accordingly, the control strategy of servo of communication of contemporary high accuracy uses magnetic field mostly directional control theory and direct torsion control are academic. Additional, as the development of microelectronics technology, digitlization already made way of a when communicate servo significant progress. Handle by digital signal (the digital control system that parts of an apparatus of Digital Signal Processing-DSP) forms has high accuracy, high reliability not only, still can simplify construction of system, add a system function and flexible. 1 number communicates servo to control the development existing state of affairs that controls a system from communication servo to look, directional control theory and direct torsion dominate magnetic field academic each has his strong point, application is endless also and identical. Use magnetic field commonly to the control of synchronous electromotor directional control, especially the control of synchronous to communicating permanent magnetism electromotor, it has control structure the characteristic such as easy implementation of software of simple, control: To the control of asynchronous electromotor both can be used, but near future research commands a respect in direct torsion more, because have magnetic field to asynchronous electromotor,this basically is directional control is extremely complex, and control effect is far be inferior to synchronous electromotor. (Dormant coordinate is A) three-phase (dormant coordinate is B) two-phase (C) two-phase rotates coordinate is a graph magnetic field of graph of principle of 1 coordinate commutation is directional control theory because each physical quantity of side of AC motor stator is communication quantity, its space vector with synchronous horn frequency 1 rotate, it is very difficult to cause control, computation. Accordingly, need have the aid of to alternate at coordinate, made Cong Jing stops coordinate department commutation rotates to synchronism coordinate is, dimensional vector commutation is straight discharge, undertake controlling. To show commutation principle, definition three-phase is dormant coordinate department, two-phase is dormant coordinate department, two-phase rotates coordinate is the 1a that be like a graph, B, C. In graph 1a, hypothesis three-phase AC motor connects the IA of sine electric current that balances with three-phase, IB and IC, the three-phase stator that generation rotates with W of synchronous horn frequency synthesizes magnetism to move Fj of power vacuum vector. In graph 1b, when two-phase position of space of fixed winding A, B(differs) of angle of 90 ° report, connect balance voltaic Ia, Ib(with two-phase angle of 90 ° report differs on time) when, also can produce identical Fj. Coordinate is being narrated to fasten before is dormant, in graph 1c, if be opposite,two mutual and perpendicular winding D, Q connects Id of dc electric current, 1q, will produce two fixed magnetism to move situation Fd and Fq respectively, make coordinate of D, Q is with synchronous horn frequency at the same time W rotates, fd and Fq also rotate subsequently, generation and before narrate equivalent Fj. Accordingly, can becoming the three-phase winding equivalent of electromotor coordinate of D, Q is two groups of winding below. The station is rotating coordinate strung looks, each vector turns electromotor into dormant vector, its each heft is straight discharge, because this decides torsion is mixed easily,be accused vector the relation between each heft, in real time computation goes out to be accused each minutes of value of a quantity of vector (dc heft) . Because these are controlled,the dc heft of vector is nonexistent on physics, still need to alternate via coordinate, from rotate coordinate department returns dormant coordinate is, the communication that becomes afore-mentioned dc the existence on physics to mensurable commutation gives an amount, undertake controlling to communicating a quantity in dormant coordinate department. Graph 2 magnetic field are directional directional control principle is like magnetic field of control principle graph the graph is shown 2 times. Speed outputs the amplitude of vector of stator electric current to give after the adjustment of adjuster of poor classics speed: Detect by rotor position circuit detects, what vector of stator electric current gets after computation is phasic, and in electric current the with vector of stator electric current amplitude in giving link is given integrated, alternate electric current of generation instantaneous three-phase gives signal: Electric current gives signal and the signal of actual measurement electric current that pass commutation to be compared, adjust via voltaic adjuster again and modulation of output pulse width (signal of Pulse Width Modulation-PWM) , in order to control communication servo electromotor. Its key is the amplitude that will control vector of stator electric current through solving Ou and dimensional position. If the graph is shown 3 times,direct torsion controls principle of pilot of academic and direct torsion. This theory slam the door the solution Ou in directional control theory dominates magnetic field, and undertake by stator magnetic field directional. With the analytic method of dimensional vector, the measured value of electric current of stator of three-phase of have the aid of and voltage leaves in stator coordinate, the real value of computational magnetic flux and torsion, undertake comparative with the set-point of magnetic flux and torsion, after adjusting via torsion and magnetic flux adjuster respectively, use the position of 6 kinds of switch of inverter, have optimal control to the switch condition of inverter directly. The rotate speed coming back that dominate stator linkage namely through voltage space vector is spent and direction, in order to change the size of magnetic flux horn, the scale relationship that uses torsion and magnetism current flow angle achieves the goal that controls torsion. It omited trival dormant coordinate and rotate the vector commutation between coordinate and much coordinate commutation consideration, need not have electromotor maths model simplify processing, not normally PWM signal generator. It has control construction of system the physical concept of processing of direct, signal makes clear method of simple, control wait for a characteristic. This torsion that controls a system is answered rapid, without exceed tone, it is one kind is had move higher, the communication timing method of static function. Graph principle of pilot of 3 direct torsion pursues we use module of control of servo of communication of number of DSP of module of control of servo of 2 numbers communication and its structure the digital communication servo that is based on DSP controls module, designed pattern plate of two collateral control. This pattern plate is compositive DSP is the smallest system, in the system but process designing (In-System Programming-ISP) parts of an apparatus, model / several (A/D) changeover parts of an apparatus. The hardware that uses this pattern plate to need to be able to form place to need by software according to controlling a target only controls module. To reduce the complexity of pattern plate structure, raise versatility and dependability, comprise sheet by ISP parts of an apparatus piece the number is inputted / output (I/O) hardware circuit. Need to call I/O software and control software only in applying actually, can comprise magnetic field of total number word directional control module and total number are direct torsion controls module. Before one kind applies at the control of synchronous electromotor, hind a kind of control that uses at asynchronous electromotor. The motor that in the experiment we use is electromotor of servo of synchronism of communication permanent magnetism, use magnetic field so directional control module. Its structure is shown 4 times like the graph. Graph 4 magnetic field are directional control module structure pursues its job principle is: By hardware (A/D, ISP) changes feedback signal into digital signal, DSP has sampling and consideration to these digital signal, give signal according to speed, by affirmatory magnetic field control of directional control law is accused object, its control signal output to produce circuit to the PWM signal in ISP parts of an apparatus, generate the PWM signal of a need, control electromotor through intelligent power parts of an apparatus. Digital I/O circuit uses IspLSI1032-80 of ISP parts of an apparatus to design digital I/O circuit. Model of its market established practice is 6000PLD equivalent door, circuit of whole number I/O can be accommodated completely in an ISP parts of an apparatus, and the parameter of circuit of the door inside same chip, trigger has consistency. Additional, the circuit that score of interference rejection function makes from parts of an apparatus had huge to rise. Digital I/O circuit is shown 5 times like the graph. Graph the output that circuit of 5 numbers I/O uses ISP parts of an apparatus 3 condition amortize is characteristic, comprise output 3 condition door, go up to DSP data bus line repeatedly, the door accuses signal by DSP read / write signal, piece in choosing signal to wait to accuse signal to produce circuit in the door, be combined and become, connect 3 condition door make can be carried. The number is fourfold the orthogonal encode pulse that frequency circuit gives out photoelectricity coder (A photograph, B photograph) fourfold frequency pulse and electromotor arise to turn to signal after fractionize, use for computation and sampling. After the sampling pulse that sampling signal forms circuit to give out DSP and fourfold frequency pulse are integrated, by data the lock is put, the order that suspends to clear of application, tally issues pulse signal, control the order of sampling logic. Need to control the object demand to I/O according to differring only in application, call to it relevant I/O software downloads ISP parts of an apparatus in, can make needs digital I/O circuit. 3 tests result we control servo of DSP number communication module to be in electromotor of synchronism of communication permanent magnetism is aspirant went experiment. Place is MFA150MB5 with electromotor model. Rated output power 1. 5kW, rated electric current 7.
5A, 2000r/min of rated rotate speed, coder output pulse is 2500 pulse / R. If experimental result pursues 6, 7. Graph weaveform of 6 electromotor phase current pursues 7 electromotor rotate speed rank jump answer characteristic graph the 6 phase current that are electromotor are undee: Graph 7 it is electromotor sky carry Shi Congjing to stop the rotate speed of 500r/min rank jump answer characteristic curve. Experimental result makes clear, servo of designs DSP number communication controls module to have taller control precision and faster answer speed. This module undertook trying moving in system of numerical control of much coordinate linkage. Moving result makes clear, as among them the speed core of the positional closed-loop control of a coordinate, it can make sure positional servo controls precision to achieve design requirement. The servo of DSP number communication that 4 last words design controls module to have compositive compact, facilitating maintenance debugs degree of tall, structure, can suit to wait for a characteristic at a variety of control objects. Range of this module application is wider. Additional, to dc motive servo control, pace receives electromotor control and communication linear electromotor control, also can control software according to needing to design, in order to comprise the control module that place needs. CNC Milling
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