Apply to industrial campaign pilot to measure a technology

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Industrial campaign control covers a series of application, the fan that includes to be based on inverter or pump control, have automation of more complex factory of communication drive pilot and advanced automation application (if have robot of advanced servo pilot) . These systematic need detect and feedback many variable, for example position of dc link electric current or electric current of electric machinery winding or voltage, voltage, rotor and speed. In function of such as appreciation (be like condition monitoring) in waiting for consideration element, cost of system of framework of terminal application demand, system, target or system are complex degree of alternative that will decide variable and need measurement precision. According to the report, 40% what electric machinery takes global total specific power consumption, compasses of law of nations pays attention to the systematic efficiency that whole industry campaign applies more and more, accordingly, these variable are more and more important, especially electric current and voltage. Article general applies according to demand of performance of electric machinery rated power, system and terminal, the electric current in discussing all sorts of electric machinery to control signal catenary develop to attack mainly and voltage detect. Here the circumstance falls, because sensor choice, electric current keeps apart converter of requirement, modulus,the implementation of catenary of signal of electric machinery control is met (ADC) choice, system is compositive and what systematic power comsumption and ground connection differentiate is different and somewhat difference. A collection of illustrative plates of industrial drive application arrives from simple inverter complex servo driver, electric machinery controls application to cover a series of electric machinery types, but the electric machinery that all electric machinery all include specific power form controls a system, and have different level detect and feedback, but modulator of drive pulse width (PWM) the processor of module. Graph 1 it is those who apply a collection of illustrative plates to simplify graph, revealed complex degree from left to right all sorts of systems that improve stage by stage, it is simple control system above all, be like need not the pump that nicety feedbacks to use simple microprocessor to be able to come true only, fan and compressor. As the system complex spend rise (namely of tend a collection of illustrative plates relatively high end) , requirement of complex control system feedbacks accurately and high speed communication interface. Bring sensor or the electric machinery of vector control induction that do not carry sensor or permanent magnetism electric machinery for example, and be aimed at a graph 1 in the drive of high power industry that show efficiency and designs (like large pump, fan and compressor) . The top end of a collection of illustrative plates is complex servo driver, use at robot, machine tool and stick the application such as a machine. As the system complex spend rise, detect variably and feedback becomes more and more crucial. Driver framework system differentiates all sorts of problems may be encountered when the system that we satisfy all sorts of industry campaign to control applied demand in the design. If the graph is shown 2 times,general electric machinery controls signal chain. Graph demand of segregation of catenary of signal of control of 2 general electric machinery is very significant, normally the circuit develop to generation attacks and the framework is had showing an effect. Need considers two crucial factors: The reason of segregation and position. The requirement that keeps apart classification depends on former. The likelihood asks high-pressured safety is kept apart (SELV) in case electrical shock, or so that functional segregation is in blame is deadly undertake n is changed between voltage, or to realize data integrality to eliminate noise requirement undertakes keeping apart. Segregation position by systematic anticipation normally function is decided. Electric machinery control is normally undertake in the harsh environment that is full of electric noise, adoption design needs to bear normally of hundreds bend over in all modular voltage, switch may fall in the frequency that exceeds 20 KHz, have rise time of extremely high transient state Dv/dt. For this, the high-power system with the system with more expensive function and inherent more expensive noise can design the power form that keeps apart with control stage appearance to have normally. No matter be,use single processor or double processor to design metropolis influence to keep apart the position. In the system of low power comsumption with inferior function, it is in digital communication interface aspirant travel is kept apart normally, this means power level and control class to be in same potential. Low end the communication interface bandwidth that the system requires to keep apart is inferior. Because high-end system asks to have taller bandwidth, and traditional segregation technology has limitation, accordingly, the communication port that keeps apart high-end system can compare difficulty normally. But the CAN that keeps apart as magnetism and RS-485 are sent and receive implement of the product come out, the circumstance is occurrent change. In design of control of electric machinery of high-powered closed circuit, two crucial component compose make PWM modulator output and electric machinery phasic electric current feedbacks. Graph 3a and graph 3b revealed need to have the place of safe segregation, specific place depends on control class is share same potential with power level or be with ground connection fiducial. No matter why be planted circumstance, high-end grid driver and electric current detect node needs to keep apart, but the segregation grade in graph 3a is different, these node need to undertake the function is kept apart only, and in graph 3b, the personnel safety of these node is kept apart (namely electric current is kept apart) crucial. The systematic power that electric current measures technology and develop to attack to be narrated except above paragraphs place with what voltage detects and ground connection differentiate outside, what because choice of requirement of segregation of sensor choice, electric current, ADC and system are compositive,the signal catenary that to detect electric current realizes with voltage still meets is different and somewhat difference. The signal recuperation that be measured to realize high fidelity and undertakes is not easy thing. For example, small signal or deferent number signal restore to have challenge sex very much in so noisy environment, and segregation imitate signal is bigger challenge. Below a lot of circumstances, signal segregation circuit can cause phasic defer to make a system dynamic function suffers be restricted. Phasic electric current detects especially difficult, because of node of circuit of this node connective and power level (inverter module) the node that the grid driver in core outputs is identical, because this is keeping apart power source and switch twinkling,change the requirement of the respect is identical also. Normally 3 keys decide what in needing to control a system in electric machinery, carry out to survey signal chain because of always under the basis (technology, signature manage and ADC) : 1.

The decision measures the dot in the system of demand or node. 2.

Level of electric machinery power and the sensor that choose finally (whether does itself have isolating function) . Sensor chooses to affecting the choice of ADC greatly, include converter framework, function and imitate input range. 3 terminal apply. This can be driven detect the to high resolution, precision or speed need in signal catenary. For example, the control that does not take sensor in the implementation inside bigger speed limits asks to undertake more, more frequent, more accurate measurement. Terminal application still can affect the demand of pair of ADC functions. For example, much axle control may need a passageway to count taller ADC. Electric current and the voltage sensor is the most commonly used electric current sensor in electric machinery control spread effect of resistor, Huo Er for cent (HE) sensor and voltaic transformer (CT) . Although divide galvanic block to have isolating function and can be when electric current is taller occurrence loss, but they are all minimum of linear, cost is provided most in sensor and the sensor that applies to communication and dc to measure. Be 50 A to restrict the signal n attenuation of billabong power loss to use billabong restriction normally or lower. CT sensor and HE sensor can offer inherent segregation, because this can be used at electric current more expensive system. But their cost is higher, and employ the solution of this kind of sensor employ the solution of billabong resistor not as good as on precision, because the initiative precision of itself of this kind of sensor is poorer,this is perhaps be in the precision of temperature respect is poorer. Graph 3a is 3b of fiducial control level figure to be standard control form to remove sensor type with ground connection with power level outside, still a lot of optional electric machinery electric current measure node. Electric current of average dc link can satisfy control requirement, but in higher drive, electric current of electric machinery winding uses as advocate feedback is variable. Electric current of direct and phasic winding measures the choice that is ideal, can use at high-powered system. However, in every low inverter is brought it is OK that spreader is used on the foot or individual spreader is used in dc link electric current of indirect measurement winding. The advantage of these methods depends on, billabong signal all with common power source is fiducial, but from dc link extraction winding electric current asks sampling and PWM switch are synchronous. Use above a kind of any electric current detect the technology all can undertake electric current of direct and phasic winding measure, but must keep apart billabong resistor signal. Gao Gongmo amplifier can offer a function to keep apart, but personnel safety segregation must be offerred by segregation type amplifier or segregation type modulator. Graph 4 segregation type and graph of feedback of electric current of electric machinery of blame segregation type 4 revealed feedback of afore-mentioned of all kinds electric current to choose. Although need only,the choice can undertake one kind controlling feedback among them, but still can use signal of dc link electric current as backup signal is protected with undertaking. The place before be like is narrated, systematic power and ground connection differentiate to keep apart those who decide need classification, judge an applicable feedback thereby. Target function of the system still can affect sensor to choose or measure a technology. Review whole performance a collection of illustrative plates, still can realize a lot of configuration. Low function give typical examples: Common the power level on potential and control class, detect option A or B use the billabong that cite a base is a kind most the electric machinery electric current of economic material benefit measures a technology. In this exemple, power level and control class share same potential, nonexistent want processing in all model, and the output of option A or option B can join directly recuperate circuit and ADC to signal.

This kind of develop attacks the low power comsumption that has ADC and low performance system are set in processor of common Yu Wei. High-powered give typical examples: Control class ground connection, detect option C, D or E are in this exemple, need undertakes personnel safety is kept apart. Detect option C, D and E all likely. In 3 all option, option E offers the most high grade electric current to feedback, and serve as high-powered system, the likelihood in the system is put in the processing of FPGA or other form, can offer the digital filter that applies to segregation modulator signal. To the ADC choice of option C, use schism type to keep apart sensor normally (probable it is closed circuit HE) , in order to come true more current than using embedded the performance with ADC higher product. With in all modular amplifier is compared, the option D in this configuration is segregation type amplifier, because need undertakes safe segregation. Segregation type amplifier can make function suffers be restricted, because this is embedded,ADC solution can satisfy need. Compare with option C or E photograph, this option can offer the voltaic feedback of fidelity lowest. In addition, although but will embedded ADC regards as " free " , segregation type amplifier regards as " cheap " , but additional component still needs to undertake deflection compensation and n are changed normally when carrying out, match in order to undertake ADC inputs limits, raised the total cost of signal catenary thereby. In design of electric machinery control, can use a lot of develop to attack detect electric machinery electric current, need to consider a variety of factors, for example level of cost, power and performance level. The main goal of personnel of most system design is to improve electric current to detect feedback, improve efficiency in order to be inside range of its cost target. To relatively high-end application, electric current feedbacks not only to efficiency, and measure to other system performance (if trends is answered, noise or torsion are fluctuant) crucial also. Very apparent, attack in all sorts of practicable develop in, existence function by low to expensive successive system, graph 5 pursue for rough map, revealed low power and high power option. Graph 5 electric current detect develop attacks target of personnel of design of system of control of electric machinery of function a collection of illustrative plates, demand and development trend: Shed resistor and segregation type ∑ to cent from HE sensor changeover - the billabong resistor of Δ modulator coupling can offer the most high grade electric current to feedback, among them, voltaic report flatfood is quite low, can satisfy billabong requirement completely. Current, the apparent apt of systematic design personnel is changed to billabong resistor from HE sensor, and with segregation photograph of type amplifier plan is compared, design personnel returns apt to adopt plan of segregation type modulator. Change merely sensor itself can drop stock detailed account (BOM) the precision that assemble cost with PCB and raises sensor. Billabong resistor is oscillatory to magnetic field or machinery all not sensitive. Replace HE sensor the system that is billabong resistor to design personnel to often can choose to keep apart type amplifier, before continueing to use the ADC that uses in the design that is based on HE sensor will restrict signal catenary medium n changes. However, the place before be like is narrated, no matter ADC function how, this function will be kept apart the limitation of type amplifier function. And replace segregation type amplifier and ADC further to keep apart type ∑ - Δ modulator can eliminate function bottleneck, improve a design greatly, can promote 12 its from the 9 high grade feedback to 10 normally. In addition, still can configure processing ∑ - the digital filter that Δ modulator output needs, in order to realize way of fast OCP annulus, eliminate imitate to shed protection too thereby (OCP) circuit. Accordingly, any BOM analysises should include to keep apart type not only amplifier, primitive ADC, both the signature between manages, and still should include eliminable OCP facility. Does AD701A keep apart type ∑ - the ICoupler that Δ modulator is based on ADI company? Technology, have ± 250 MV (the full span of ± 320 MV that is used at OCP normally) limits of the input that need branch, suit block sex spreader to measure particularly, it is the good product selection that enlarges this trend. Imitate modulator lasts to imitate input sampling, and the form that inputs information to shed density with data is included in the number output flows inside, its data rate is top can amount to 20 MHz.

Through proper digital filter (the Sinc3 filter that measures to apply to accurate electric current normally) can reframe original message. Because can be in,change function and bandwidth or filter group balance is made between defer, can offer fast OCP to answer with the quantitative class of 2 μ S because of this briefer, faster filter, special apply to IGBT protection. Will look to narrowing the demand of billabong resistor dimension measures a respect from signal, current a few main difficult problem and choice billabong resistor are concerned, because need the balance between implementation sensitivity and power comsumption. Large block value will ensure use ∑ - of Δ modulator whole or use up generous imitate to input limits, win the biggest dynamic range thereby. But, because resistor is met the loss of R of occurrence I2 × , accordingly, large block value still can bring about voltage to drop with loss of efficiency. Of resistor itself what send fuel factor and bring about is nonlinear the circumstance also can be the challenge that uses greater resistance place be faced with. Accordingly, systematic design personnel is faced with or so balance to accept or reject and the consequence of farther aggravation, they often need to choose the billabong resistor of a proper size, in order to satisfy the requirement of all sorts of model below n of different electric current and electric machinery. If face multiple at electric machinery the peak value electric current of rated electric current, need to capture reliably both value, holding dynamic range also is a difficult problem. Control system switchs on the mobile phone to the ability of peak value electric current can differ because of the design and have very big difference, move such as from float of above of rated electric current the strict control of 30% , to be as high as the 10 times coefficient at rated electric current. Quickly and load or torque change also can produce peak value electricity. But, inside the 4 times limits that the peak value electric current in the system is in driver to design rated electric current normally. Face these difficult problem, systematic design personnel is being searched have wider trends limits or have taller letter to a confusion of voices is compared and believe accept to compare (SINAD) high-powered ∑ - Δ modulator. Newest segregation type ∑ - Δ modulator product has 16 resolution and can ensure be as high as 12 effective digit (ENOB) function. SINAD = (6.

02N + 1.

76) DB, among them N = ENOB complies with the trend that uses billabong resistor in driver of low power comsumption, manufacturer of electric machinery driver stems from the consideration of function and cost respect, also trying to enhance the rated power of the driver that can use this develop to attack. Exclusive and feasible method uses the billabong resistance with block little watch namely, and this need introduces the modulator kernel with higher performance, in order to differentiate abate signal extent. The system designs staff (especially servo designs staff) still exploring ceaselessly, try through shortening modulus changes time, perhaps pass use with segregation ∑ - Δ modulator and billabong resistor develop attack the kind that electric digital filter reduces group of delay raises a system to answer. The place before be like is narrated, can mix in changeover function bandwidth or filter group balance is made between defer. Briefer, faster filter can offer faster response, but can reduce performance. Systematic design personnel analyses filter wavelengh or draw-out compared result, apply demand to make balance according to its terminal next. Raise the clock rate of modulator to be able to be helped somewhat, but the 20 MHz that a lot of design personnel already realized to support in AD7401A is operated below highest clock rate. A defect that raises clock rate is radiation potential and interference (EMI) effect. Below same clock rate, the modulator with higher performance is ameliorable the balance that exists between group of defer and function concerns, realize faster noise to answer below the circumstance with function minor influence thereby time. CNC Milling CNC Machining