Saturated inductance reachs his to apply mediumly in switch power source
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Inductance can divide the classified saturation of 1 saturated inductance to be able to accuse saturation to be mixed from saturation 2 kinds. 1.
1 from saturated inductance (Saturableinductor) quantity of its inductance follows the voltaic volume that carry alterable. If core magnetism character is ideal (show rectangle for example) , if pursue 1 (A) be shown, when saturated inductance works, be similar to " switch " , namely the voltaic hour in winding, core is not saturated, winding inductance is very big, be equivalent to " open circuit " ; When the electric current in winding is big, core saturation, winding inductance is small, be equivalent to switch " short circuit " . 1.
2 can accuse saturated inductance (Controlledsaturableinductor) says to be able to accuse saturated reactor again (Controlledsaturablereactor) , its fundamental is, the communication coil that brings core falls in dc excitation action, because deliver direct current at the same time excitation, make core condition changes by local magnetism loop-line inside one cycle, accordingly, changed conductance of core equivalent magnetism and coil inductance. If core magnetism character is ideal (B - H character shows rectangle) , can accuse saturated inductance to be similar to " can accuse switch " . In switch power source, application can accuse saturated inductance to be able to absorb surge, restrain aiguille, eliminate oscillation, with when restoring rectification to run series quickly, can make rectification canal loss is reduced. If pursue 1 (B) be shown, can accuse saturated inductance to have rectangle of loop-line of tall magnetic hysteresis to compare (Br/Bs) , I of μ of conductance of tall initiative magnetism, hc of force of low correct dense, apparent magnetism saturation is nodded (A, b) the area that because place of loop-line of its magnetic hysteresis is surrounded,reachs is narrow and make its high frequency magnetic hysteresis loss is lesser wait for a feature. For this, can accuse saturated inductance to be in two when use a field marked characteristics 1) because intensity of saturated magnetic field is very small, so, but of saturated inductance store can ability is very weak, cannot be regarded as store can inductance is used. But of saturated inductance the biggest store can the theory of Em is worth usable type (1) express. In type: μ nods magnetism conductance for critical saturation; H nods magnetic field intensity for critical saturation; V is the effective bulk of magnetic material. 2) as a result of but the initiative magnetism conductance of saturated inductance is tall, magnetoresistive is small, inductance coefficient and inductance amount are very large, in bring to bear on when exterior voltage, initiative electric current grows inductance interior slow, after the delay time that passes Δ T only, when inductance coil medium electric current reachs fair numerical value when, but saturated inductance just is met instantly saturated, be regarded as in circuit middling consequently can accuse component of delay time switch to use. 1.
2 but the relation that saturated inductance changes along with electric current because, air gap and the computational method that do not have the DB/di magnetic circuit of air gap differ, so, undertake discussion to two kinds of circumstances respectively. 1.
1 without air gap but the relation of saturated inductance and electric current does not have air gap but the relation that saturated inductance L changes along with electric current can use formula (2) express. In type: W is inductance winding v/LIT all over the ground number; I is magnetizing current; F uses the corresponding function of curve of H of ～ of magnetic material B for inductance; S is the cut area of magnetic material; Of L magnetic material for average length. 1.
2 have air gap but the relation random of saturated inductance and electric current gives to guide B1 of intensity of the magnetic induction in magnetic body magnetic circuit, can beg by B=f(H) curve piece guide the H1 of magnetic field intensity in magnetic body magnetic circuit. The H0 in air gap is worth usable type (3) express. In type: B0 is intensity of magnetic induction of empty air gap; A and B are edge of area of cut of magnetic circuit rectangle to grow; L0 is air gap length; μ 0 for air magnetism conductance. By magnetic circuit law change B is worth and repeat afore-mentioned measure, can beg a corresponding I, get the concern data of a group of B and I. The function that sets this B and I correspondence is B=f1(I) . When taking no account of leakage to feel, the computational type of inductance can use formula (4) express. 2 saturated inductance apply mediumly in switch power source 2.
1 aiguille is restrained implement interference of the aiguille in switch power source basically comes from power switch canal and diode of 2 side commutate debut and close the instant. Have easy saturation, store can the saturated inductance that waits for a characteristic infirmly can control capacity effectively interference of this kind of aiguille. saturated inductance and rectification diode series connection, in the instant with elevatory electric current, it presents tall impedance, restrain aiguille electric current, and amount of its saturation inductance is very small after saturation, loss is small. Restrain this kind of saturated reactor as aiguille normally implement. In the graph 2 show circuit in, guide when S1 when connecting, d1 guides, d2 up to, as a result of but the current limliting action of saturated inductance Ls, the amplitude that restores electric current what D2 midstream passes reversely and metabolic ratio are met reduce significantly, restrained effectively thereby high frequency guide the generation that connects noise. When S1 closes, d1 up to, d2 guides, because Ls is existing to guide,connect T of Δ of delay time time, this will affect the action of follow on current of D2, can produce tension of the aiguille that lose a value in the negative pole of D2. For this, increased to assist diode D3 and resistor R1 in circuit. 2.
2 magnetism amplifier magnetism amplifier is to use can accuse saturated inductance to guide the physics that tells delay time is characteristic, control switch power supply take sky comparing and output power. This switch character gets the control that exports circuit feedback signal, use the switch function of magnetism core namely, will realize wide control of voltage pulse arteries and veins to output the stability of voltage in order to achieve through weak signal. In can accuse saturation proper sampling and control parts of an apparatus are added on inductance, adjust its guide the time that tells delay time, can make circuit of the commonnest magnetism amplifier stabilized voltage. Circuit of magnetism amplifier stabilized voltage has voltage control and electric flow pattern to control two kinds. The graph shows circuit of restoration of the profiling that it is report 3 times, it includes voltage to detect reach error enlarge circuit, restoration circuit and control output diode D3, it is regulating system of voltage of odd closed circuit. Be shown to move manostat of amplifier of magnetism of power source of switch of ZVS-PWM of complete bridge  . Transformer of circuit of complete bridge switch 2 two-piece wave commutate receives amplifier of a magnetism each SR, its core is circled have working winding and control winding. Be in half weeks, when some output rectification canal is slanting (canal of another output commutate slants instead) , the square wave pulse that transformer deputy edge outputs is added on corresponding working winding, make SR core to magnetization (add magnetism) ; In lose half weeks, canal of this output commutate slants instead, the diode D3 that with control winding establishs ties is slanting guide, below the function that controls voltaic Ic in dc, make the core demagnetization of this SR (restoration) . The working principle that dominates circuit is: Voltage of output of switch power source and fiducial after comparing, via the error enlarge controls the grid that MOS is in charge of, MOS canal offers the magnetism amplifier that concerns with output voltage the Ic of control electric current of SR. 2.
3 move transformer of ZVS-PWM of complete bridge moves transformer of ZVS-PWM of complete bridge combined 0 voltage switch to allow the good point with syntonic technology and traditional PWM both technology, working frequency is fixed, LC resonance is used to make in commutation process parts of an apparatus 0 voltage switch, still use PWM technology after commutation ends deferent energy, control is simple, switch loss is small, reliability is high, it is one kind agrees with big in the soft switch circuit of power switch power source. But become when load is very light, especially the ZVS condition that switch of lag bridge arm provides is satisfied hard. Will saturated inductance serves as move the syntonic inductance of transformer of ZVS-PWM of complete bridge  , can expand to carry next switch power source gently to satisfy the limits of ZVS condition. In applying its at power source of arc solder inversion  , can reduce energy of add annulus road and the loss that take sky comparing effectively, on the foundation that assures efficiency, expanded the laden limits of 0 voltage switch, raised the dependability of power source of inversion of solder of soft switch arc. The segregation transformer of will saturated inductance and switch power source outputs rectification 2 times to run series, can eliminate parasitism oscillation 2 times, reduce circular energy, make move of power source of switch of ZVS-PWM of complete bridge occupy sky is the smallest than the loss. Divide this beyond, will saturated inductance and capacitance are strung together receive in move transformer of power source of switch of ZVS-PWM of complete bridge  , canal of lead arm switch works by ZVS; Be bordering on zero hour when load current hasten, inductance quantity increases, prevent electric current to change reversely, created lag arm switch to provide ZCS condition, implementation moves transformer of ZV-ZCSPWM of complete bridge. 2.
The transformer of series connection resonance that 4 syntonic transformer use series connection inductance or saturated inductance [if 6] pursues show 5 times. When syntonic inductance electric current the job is when successive condition, switch canal is 0 voltage / 0 electric current close, but debutting is hard enlightened, existence opens loss. Turn over shunt-wound diode to debut for nature, but close to restore electric current reversely from time to tome, accordingly, turn over shunt-wound diode to must be used fast restore diode. To reduce the enlightened loss that switch runs, realize 0 electric current to debut, can make switch is in charge of series connection inductance or saturated inductance. Before switch canal is enlightened, saturated inductance electric current is 0. When switch canal is enlightened, the electricity that switch of saturated inductance limitation provides rises rate, make switch tube current from 0 rise slowly, the 0 electric current that realize switch canal thereby are enlightened, improved diode at the same time involve a requirement, eliminated resume an issue reversely. 2.
5 inversion power source [it is good that power source of 7] inversion controls function with its, efficiency is tall, volume is minor wait for a lot of advantage, be used extensively at automata, electric power electron reachs each sides such as accurate instrument. The character be closely bound up of its function and whole system, especially the dynamic function of power source. Because inversion report comes from the characteristic of the body, its trends character is insufficient all the time and good. Use PWM and power source of PFM pilot inversion, its job principle decided to want to get flowing voltaic voltage weaveform, inductance of follow on current must be added on its output circuit, and the main factor that this inductance affects performance of trends of inversion power source just about. To constant voltage source, inductance electric current and load concern completely into inverse ratio; To can controlling constant current source, should make electric electrification flows by small greaten, want to serve as premise with little laden value necessarily, although not be complete corresponding relation, but the change that can say electric current is in go up somehow the change that reflected load. Accordingly, use the inductance that increase along with electric current and reduces to regard the output of inversion power source as inductance, can change power source effectively to output the time constant T of circuit, make its become inverse ratio completely with R (T=L/R) , maintain inside laden span then go up relative to lesser numerical value in, so natural meeting improves dynamic performance. 3 epilogue the article is expatiatory the change of the physical character of saturated inductance and its inductance and electric current concerns, saturated inductance was summed up to be restrained in aiguille on this foundation implement, magnetism amplifier, move transformer of ZVS-PWM of complete bridge, syntonic transformer and inversion power source use a case mediumly, analysed their working principle briefly. CNC Milling