Silicon controlled rectifier touchs those who send circuit to improve

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Summary: Introduced imitate type to touch hair circuit and digital type to touch hair circuit photograph to compare the dominant position of the problem of existence and oneself, hit the issue that sends circuit existence in the light of imitate type, put forward corresponding improvement measure, raised imitate type to touch the dependability that sends circuit work. Keyword: Silicon controlled rectifier; Synchronous; Pulse; Spark; A lot of advantage such as the voltage adjusting range with the voltage output of circuit of commutate of 1 foreword silicon controlled rectifier with its reliable function, stability, wider drive, procrastinate in electric power move, electric machinery is soft start, the respect such as direct current source got applied extensively. The first requirement that silicon controlled rectifier makes galvanic Lu Nengan move reliably completely is those who hit hair circuit is reliable spark, the demand that different rectification kind sends circuit to touching is different: If the requirement of bridge of half control of bridge of bridge of single-phase half control, single-phase fully control, three-phase is simpler, trouble gives rarely in moving, because its communicate component electric current of output report depress, output is big, big wait for a characteristic, main application procrastinates at electric power move and electric machinery is soft in starting; Communicate the direct current source with very small ripple to the requirement, use bridge of three-phase fully control generally, those who touch hair circuit to ask to output 6 each other to differ 60 ° is double narrow pulse. The 　 of actor defect 　 that 2 imitate type touchs hair circuit and digital type to hit hair circuit is current home is more the imitate formula that uses TCA785 composition touchs hair circuit and sheet piece the digital type of machine composition is touched. Digital type touchs hair circuit to spark the effect is good, but spark board itself gets used to voltage of electrified wire netting fluctuant ability is poorer, constant burn down, and cost is higher; Imitate type touchs all sorts of elements in sending circuit to suffer electrified wire netting easily to affect, spark the effect is a few poorer, pulse amplifier is easy calorific, spark power is low, affected imitate type to spark board application. How does the article solve imitate type to hit these issues that send circuit existence, receive then touch hair circuit to spark likewise with the number the effect, and cost is low, comfortable should force is powerful, put forward to improve measure. 3 imitate type touchs those who send circuit to improve measure 　 (1) solve three-phase synchronism problem, the type of imitate of influence great majority that restrains electrified wire netting to disturb an element sparks board the synchronous circuit that if the graph is shown 1 times,uses, this circuit structure is simple, yuan parts of an apparatus is little. Debug the discovery in the process: When load current is less than 10 A, spark the effect is better; But be more than 10 A when load current or when distortion of weaveform of voltage of electrified wire netting, observe from oscillograph three-phase communication inputs ABC three-phase voltage and course step-down to be restricted junior the output voltage UTA that enters TCA785, UTB, UTC appeared different situation, cause the dc after sparking to outputted weaveform to appear to lack photograph or trail of wave head wave uneven, and accident of each alternant occurrence weaveform is not neat, output voltage is flabby, communication ripple increases, affect rectification transformer, make rectification transformer noise increases, cannot achieve the requirement of direct current source to stabilized voltage precision. After we are studying an experiment through relapsing, to synchronism circuit undertook improvement, the synchronous circuit after improving is mixed in synchronous transformer be restricted joined between diode take a filter. Among them either photograph circuit is shown 2 times like the graph. Principle of this circuit job is: Alternating voltage tells the input end of filter via active is being inputted to take after step-down resistor step-down, had chosen each component parameter through formulary computation, be versed in with respect to what can allow 50 Hz to control only frequency signal is passed, the signal of other frequency is rapid damply, all sorts of harmonic in restraining electrified wire netting effectively are right spark board interference, make input synchronism of voltage of signal ABC three-phase and output signal UTA, UTB, UTC. The parameter that discovers each resistor capacitance in trying check process repeatedly is very important, the component that answers relatively each especially, must use high accuracy component or the cell that agree through choosing parameter carefully, will appear otherwise three-phase is completely not synchronous, the output weaveform that observes through oscillograph is not orderly, ripple is largish. Because this outputs complete synchronism to make sure three-phase is inputted, rise spark board working dependability, must undertake filtration to each component parameter. (2) the great majority of power comsumption problem that solves pulse amplifier sparks board what ban end stop to add in the pulse of TCA785 is 5 V volts d.c. , the working principle that pulse prohibits carrying is: Be less than when voltage 2. When 5 V, have block effect, TCA785 does not deliver pulse, be more than when voltage 2. When 5 V, do not have block effect, TCA785 outputs pulse, cause pulse amplifier permanent worker to make so in on-state, give out heat power comsumption is too big and badly. To solve this problem we ban end stop to add the modulator of high frequency pulse that comprises by NE555 in the pulse of TCA785. If pursue,3 are shown. Principle of this circuit job is: Pass formulary F ＝ 1 ／ (1. 1RC) , the size of logical choice RC, make output pulse frequency is controlled for 20 KHz, adjust potentiometer Rw makes output pulse to occupy sky comparing for 1: 4, namely the 1 ／ that pulse width occupies whole cycle only 4, the output pulse of such TCA785 became frequency and pulse of its identical high frequency modulation, checked interference signal not only, and make of dynatron guide connect time to turn into 1/4 original, reduced power comsumption, disappear gives out heat besides dynatron phenomenon. (3) spark circuit of drive of pulse of pulse drive circuit includes pulse amplifier and pulse transformer, the circuit that if the graph is shown 4 times,most drive circuit uses, because TCA785 output pulse is not high frequency pulse, so pulse transformer and pulse amplifier often are in on-state, and electric current is bigger, calorific and serious, cause pulse transformer volume bigger, drive ability is poor, cannot drive high-power silicon controlled rectifier. The drive circuit principle after improving is shown 5 times like the graph, because TCA785 outputs pulse to be pulse of high frequency modulation, so pulse transformer should use high frequency transformer, volume is minor, not calorific, yi An is installed; D3 of diode D1 ～ all uses fast diode. Principle of job of this drive circuit is: When TCA785 has pulse to output, dynatron enters on-state instantly, as a result of the action of instantaneous short circuit of capacitance, make the aiguille pulse that the signal that the deputy edge of pulse transformer gets is ＋ 24 V, it is usable those who make silicon controlled rectifier is strong spark pulse, accelerate its to guide a speed, raise the dependability that spark. After that the pulse of high frequency modulation that the pulse of high frequency modulation that TCA785 outputs makes the amplitude that transformer deputy edge gets persistent inferior, continue to be offerred to silicon controlled rectifier spark pulse, in order to increase the stability that the silicon controlled rectifier when electric current is intermittent works, also reduced the power comsumption of drive circuit at the same time. The TCA785 after the 4 effects after improving and actual application course are improved moves to if the graph is shown 6 times,touch block diagram of hair circuit principle. TCA785 is below signal of synchronous signal, high frequency modulation and the joint action that move to adjust signal, 6 groups of generation spark pulse, with oscillograph observation its spark the effect, neat of end of wave head wave, from 0 arrive to adjust the most greatly repeatedly in the process, did not appear any leap and interference are undee, although be in three-phase voltage is serious lopsided when, pulse is lopsided degree do not be more than 2 ° , pulse moves photograph limits 175 ° of 5 ° ～ , can spark completely with digital type board photograph is rivalled, through moving to be adjusted circuit can implement automation already, can pass PLC again (can make up Cheng controller) control of implementation personal computer; And cost is low (hit hair circuit for digital type only 1/4) , interference rejection sex is strong, communication ripple is less than 0. 5 V. In triumphal oil field a few transformer substation are mixed triumphal oil field moves more than 2 years on marine platform, did not appear up to now any problems. CNC Milling CNC Machining