SU1339804A1 - D.c.voltage converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used in secondary power sources. The purpose of the invention is to improve the mass parameters and the shape of the output voltage. The converter contains power cells) (к) 1 and 2, a transformer unit made with primary 3 and 4, secondary 5 and 6, and demagnetizing 7 and 8 windings. The knot for limiting the rate of increase of the voltage on K 1 and K 2 contains diodes 12-15 and choke 16. Running the transformer node on a single two-core magnetic circuit 19 with shunt 20 ensures that there is no failure on the output voltage. With the closure of K 1, the process of magnetization reversal of the magnetic circuit is determined by exceeding the number of turns of the winding 4 versus the number of turns of the demagnetizing winding 8. The voltage on the secondary winding 6 exceeds the output voltage, and is applied in the locking polarity to the rectifier 11. Before the closure of K 2 the magnetic the flux through the winding 4 is determined by the flux penetrating the winding 3, with the exception of the part of the flux branching into the magnetic shunt. With the closure of K 2, the difference in the fluxes of windings 3 and 4 increases through the magnetic shunt, the magnetic resistance increases and the magnetizing current increases during the overlap of K 1 and K 2. At the same time, the magnetic energy through diodes 9 and 10 returns to the network. 6 hp f-ly, 3 ill. (Oo with so 00 about

Description

one

The invention relates to iipcijGrjn--: ovchlny zlek trslchnnke and can be used in watts orch: i1x source -: - nlkah electric power.

The purpose of the invention is to improve the overall dimensions and shape of the output voltage,.

In FIG. 1, a representation of the npt circuit; —former, first variant; in fig. 2. - transformer unit; in fig. 3 - scheme prev), - ;. inviter, the second option.

The converter contains power switches 1 and 2, primary windings 3 and 4 connected in series with them, secondary 5 and 6, and demagnetizing 7 and 8 windings of the transformer node. Razmagn1-1chivayuschie 7 n 8 windings through a recovery diode): 9 and 10 are connected to the input, and the secondary windings 5 and 6 through rectifier 11 - transform to the output. The knot for limiting the rate of increase in the voltage of the power switches is included in the depy of the primary windings 3 and 4 and contains diodes 12-15, choke 16 and capacitors 17 and 18.

The transformer assembly is made on one (single) double-core magnetic core 19 with a connecting rod 20 installed between the rods and parallel to them, and each of the specified winding groups is located on a separate rod.

The converter according to the second variant (FIG. 3) contains at its input capacitive dividers 21 and 22.

Constant voltage converter with demagnetizing windings according to the first variant 1, phi1-. 1) works as follows.

At the moment of Burden t, when key 1 is closed, and key 2 is open, the voltage on the secondary winding 5 is applied in conductive polarity, to the rectifier 11, i.e. the output voltage of the converter is determined by the supply voltage Uo applied to the primary winding 3 via switch 1, the voltage on the winding 4 at this time exceeds the supply voltage by the value uU (the process of magnetization reversal of the magnetic circuit and the voltage uU on the winding 4 are in progress determined by the number of turns of the winding 4 versus the number of turns of the demagnetizing winding 8; the voltage on the secondary winding 6 also exceeds

.llIkhodIHle gmpri. ensh pG Eobracho pteln, 1; o it has the locking polarity of bI if it is 1 1.

Next, before closing the key 2, the voltage on the winding 3 and, accordingly, at the output of the converter remains the same key; 1 is closed; The magnetic flux through the winding 4 and the voltage across it is determined by the flux) m 5 pass: it turns on the winding 3 with the exception of the part of the flux that separates the R magnetic bypass. At the time the key 2 is locked, the voltage on the winding 4 is fixed to the damage f not v. o, before closing it was lower

Uo, due to the presence of a magnet schunt) and dal) 1iii1e change in flow in ets; th winding set / gs Appendix P {s to 1 s

 apr. 15, the difference iOTOf; oB of windings 3 and 4, which appears at the same time, is bridged through a magnetic shunt; the magnetic resistance of the circuit of windings 3 and 4 also increases the magnetizing current (the coil windings for the whole period of overlap (Fig. 1); : given the speed that U1 makes it its maximum} value, however, since the accumulated value is 30

40

45

The magnetically zero current is almost completely returned later through recurrent ion diodes 9 and 10 and the network, this increase in magnetizing current is not a disadvantage. The voltages on the windings remain no: i- 35 completely independent; m. When key 2 is turned on at the corresponding output winding 6 and, accordingly, at rectifier 11, the voltage appears before it disappears from the second arm, which ensures the absence of a dip in each case; voltage

The parameters of the magnetic shunt are selected from the sl - :: blowing; -; considerations.

Denoting by mr - magnetic

the resistance of the curtains-magnetic flux j, through to. - magnetic resistance and untiing pepi (including and resistance to air gap) and, with :: edovat. |; but not equal even in the absence of a shunt, consider the following cases.

R with / e. This means that both primary windings have an S13YAZI ratio edioiida, —that can be implemented strictly ONLY if it is the same winding ,, or closer} and 5, if both windings are wound n ;: common rod.

those. it is a transformer of a push-pull circuit,

. The two halves of the transformer are completely separated by a shunt, i.e. in practice, there may be two separate transformers. The device will be operational, but such a converter acquires a major drawback of single-ended circuits — poor use of the core, which in this case works on only one magnetic induction sign and, therefore, uses a maximum of half. In addition to increasing the volume of the core, this leads to a doubling of the number of turns of all windings and, accordingly, to an increase in the voltage drops across the windings and deterioration of the stability of the output voltages. The calculations show that the utilization rate of the core in the general form in this scheme is determined by the expression

2 +1

 / - L- fj

2 1 + 2 Rp

In this case, the magnitude of the current surge caused by the presence of a connection between two primary windings and expressed as a fraction of the no-load current

2l RI.

G p - XX

. RP

where 1 // is the no-load current.

As can be seen from the first expression,

13

at - 2 utilization rate

P of the core is 5/6. Attitude

-; - usually less than 0.1. After

Doubtfully, at - 2 magnitude popup R. p

This value is not exceeded; its value is 20% of the no-load current, which is quite acceptable

Fig. 2 shows variants for shunting the magnetic circuit 19 with a shunt insert and a shunt lining 20.

The voltage rise rate of the power switches 1 and 2 is limited by the charging time of the capacitors 17 and 18. In order to reduce the dynamic losses during the overcharging of the indicated capacitors, at the stage of preparation for the next moment of switching off the corresponding one from the power transistors 1 and 2, the choke is installed 16 Diodes 12H133980A15 serve as a DCF of the charge-and-discharge circuits of capacitors 17 and 18.

The ratio of turns in the primary .. 3 (4) and demagnetizing 7 (8) windings in the converter determines the ratio.

ten

T4-

K ii ± F T-

where T is the duration of the conversion period;

C is the duration of the rising edge of the voltage when the switch is interrupted by a key, the value of which is determined by the necessary limitation of losses on the transistor of the corresponding key of the element.

The operation of the Converter made according to the second option (Fig. 3), similar to the above. The difference is that the converter is powered from a primary source having an average potential of the first output, or the average potential point is formed by installing a capacitive voltage divider at the input.

thirty

Claims (7)

Invention Formula five 0 five one . A constant voltage converter containing two single-ended power amplifiers connected in a push-pull converter circuit, each consisting of a transistor and a transformer with a primary, secondary windings and a demagnetize circuit, the power leads of the transistor of each single-ended power amplifier connected through the primary winding transformer to the corresponding input pins of the single-ended power amplifier, and the secondary windings to the output pins, characterized in that, in order to improve the masses ogabaritnyh indicators and form; the output voltage, the transformers are made on one double-rod 0 magnetic core and the upholstery of each transformer is placed on a separate rod. 2. The converter according to claim. About the fact that the corresponding input terminals of single-ended power amplifiers are connected and connected to the input terminals of the converter, and the circuit is demagnetized The device is made in the form of a demagnetization winding diode, KOTOI HH is placed at each slot on the magnetic conductor and connected via an appropriate diode to the input terminals, 3, The converter according to any one of the preceding claims, so that the corresponding input terminals of the single-ended power amplifiers are connected in series and connected to the input terminals of the converter, to which the capacitive divider is connected, the midpoint connected with the combined dissimilar input pins of single-ended power amplifiers, each with a demagnetization circuit. Made in the form of a series-connected regenerative diode and O the winding is demagnetized: and 5 is the primary winding section, and is connected between the midpoint of the divider and the opposite input pin. 4, the Converter according to p. 1. It is about the fact that the magptopath of the transformer contains a magnetic shunt, installed -1 between the rods and parallel to them, 5, the Converter according to claim., Which means that the number of turns of the demagnetizing winding is less than the number of turns of the primary winding. 6, ilpei,) 6pa3; ii a; el ;; nn,, o tL and h a 1 (1 IU and il s i; i: M, 41 C; 5 s K oa pObBIeni; ml, (;: De1 speed limit node HajiacTanHH and four / -iods, connecting yit HHi-ix in pairs and following 1: l; ... but into chains, one) obo, the ends of which are connected and connected via a choke to one input terminal of the converter, and the other ones are connected to another the input terminal of the converter, and the midpoints of the indicated chains are connected via coide to the points of connection of the transistors with the primary windings. 7. The Converter in PP. 1 and 3, about tl and ch and y C and with the fact that, with:;.; 0 five tripolar, containing each two series-connected: a diode connected to their common end point}; a sator and a throttle connected to a free state; one of the diodes, Another VIVOT throttle is connected to the middle point of the capacitive divider and the other capacitor outlets to the common point of connection of the transistor with the primary winding, and i) and the free pins of the diodes are connected to different each input recuperator, and each recuperator-: io} is the 1st w diode with a branch corresponding to 1H; next to 11 the primary winding. nineteen FIG. 2 + O2 / ft7 sixteen 44 % 2Wc sixteen 22 - Composer N.Tsishevsk Editor G. Volkova Tehred I.Hodynnch 4240/51 Circulation 659 Subscription BfiHHIIH USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35. Raushsk nab. 4/5 Production and printing company, Uzhgorod, st. Design, L : f7 L / W .- Y2J Corrector C.DJeKMap