TWM254007U - Forward power converter with self-excited synchronous rectification circuit - Google Patents

Description

M254007 、 Creation theory (]) The new technical field] A kind of self-excited synchronous rectifier f, especially a kind of self-excitation using a transformer, the induction type I winding coil generates electric energy, and then controls | to achieve synchronous rectification Forward power converter. Two [Previous technology] Switching power supply (SPS) has been widely designed. The switching power supply (SPS) 提升 The improvement of the density f has become the most important current known DC power supply for designers. Supply equipment, such as switching ^ t (AC To DC Switching Power Supply) ^ Most of the transformer volume uses high-frequency pulse width modulation system ^ stream wheel out, pressure, as shown in the first figure, is a conventional converter Circuit diagram. It is mainly composed of the power switch Q transformer pole Dl 'D2' D3, the output inductor l and the output capacitor c. The principle is briefly described as follows: When the pulse width modulation controller U1 controls Q1 to be turned on (0N), The input voltage VI will supply power to the variable winding N 1 'At this time, a current will gradually flow through the winding and be stored therein. At the same time, the secondary winding N2 of the transformer will sense a voltage of the same polarity as that of the secondary winding N1, so the energy is transferred in the forward direction to the group N2 ′, passes the diode D1 and the output inductance L, and then passes i 1 oad. At this time, the diode D2 is in a reverse bias state. The body D2 is a forward diode. Source converter ’crystal on the secondary side of the converter, with the aim of f-signal and lightness, shortness and efficiency of home appliances. Type power supply > In order to reduce (PWM) directional power converter T1 and two components, its basic power switching voltage transformer T1 is the first and energy storage is transferred to the secondary winding i to the load end. And the description of the creation of the two-pole M254007 (2) Winding: Ξ ί: J is turned off (0FF), at this time the transformer T1 is turned on (OFF)-this, so that the diode D1 becomes a reverse bias without the diode D2 is commonly referred to as the polar body D2 and then enters the on-state (ON) state, and the load end load can be two of the 7-pole body (at 17 " ^ 61 di〇de). At this time, the energy is stored as an energy storage element by the output inductor L and the output capacitor C via the -pull system. ; Seven, give. It can be known from this that the output inductance L refers to the figure _β, _ β, the function of the η of the secondary circuit and the under-voltage transformer T1 is to make the relationship between the primary circuit and the two ratios # 彳 3, At the same time, the number of windings can be used to obtain the output voltage required by the load terminal. The reverse direction of the diode diode is the conventional forward power converter. When the conductor M is turned on, it can be shown at two ends: 2 current waveform. When the two poles can measure the conduction voltage τris-reverse conduction voltage Vrrm at the same time, and the voltage is equal to 1, the helmet is Cheng Dian Ic. As shown in the second figure, at time to-

The system is connected to the diode D2 and D2. The conduction current I c of U D1 gradually increases to fh, and reverses; conduction :: 牯 '-polar body potential. The thinking voltage Vrrm still maintains high exchange finger loss: the rotor is turned on, and the pole body D and D2 are exchanged. During the period, a report of heroic loss (switching 10Ss) was reported. [New content] Directional = This, this is a kind of self-excited synchronous rectifier circuit 2 = converter 'The purpose of this is to transfer the knowledge to the direction The power converter is replaced by: the first "transformer; the primary winding is replaced, the forward diode in is replaced, and the field effect transistor is replaced. By the self-excitation of the transformer; the secondary winding of the transformer generates electric energy by induction, and then controls

$ 6 pages M254007 Fourth, creation instructions (3) N-channel field effect transistor to achieve synchronous rectification of forward power conversion. This invention creates a forward power converter with a self-excited synchronous rectifier circuit, which uses a PWM controller to drive the switching action of a power electronic switch, so that an input power can pass through a first transformer and a synchronous rectifier circuit. And an energy storage is transmitted to a load. The synchronous rectifier circuit is connected to a terminal of the first side of the first transformer using an N-channel field effect transistor. The source terminal is connected to the positive terminal of a flywheel diode. The negative terminal is connected to the other end of the secondary side of the first transformer. At the same time, the control terminal of the N-channel field effect transistor is connected to one end of an induction coil through a resistor and a capacitor, and the other end of the induction coil is Connected to the source terminal of the N-channel field effect transistor. In the above description, the energy storage system includes at least a primary winding coil of a second transformer and an energy storage capacitor, and the induction coil is a secondary winding coil of the second transformer. Therefore, when the power is provided in the forward direction, the energy is established in the primary winding of the second transformer, and the self-excitation of the second transformer is used to make the secondary winding of the second transformer induce electric energy and transmit it. To the control terminal of the N-channel field effect transistor, which is used to drive the ON of the N-channel field effect transistor. When there is no input power supply, the first transformer system cannot supply power. At this time, the primary winding coil system of the second transformer changes polarity and transmits the stored energy to the load through the flywheel diode, so that the load can continue to work. Without power failure. The secondary winding of the second transformer also changes its polarity at the same time, which drives the N-channel field effect transistor to turn off. In addition, when this book is created under no-load power supply, the secondary winding coil induces electricity.

M254007 Creative Note (4) | Can be smaller than the mt channel effect transistor | The channel effect transistor cannot be turned on. The drive voltage point is limited, so that ^ pass at the same time, this creation of a white 丨 power converter, which can use the secondary two: the forward direction of the rectifier circuit and the second aid of the controller when no-load power supply The soil controller is used, so in addition to the working power of =% 疋, the frequency of the pulse width is automatically reduced to reduce the loss of the conversion world. The JS cycle controller will be used in the air cutting. Converter main: Forward type | polar body of self-excited synchronous rectifier circuit, and use 戌 ': N-channel field-effect transistor to replace the conventional two N-channel field-effect transistor, which means that the pan-coil coil induces power when forward power is supplied. It is used for driving to improve the working efficiency, so that the power consumption of the circuit can be reduced, and the power consumption can be reduced. And the overall power loss at no-load [Embodiment] The required input power to the regulations is less than 1 W. Please refer to the second diagram of the forward power supply of No. = and | 'This is a schematic diagram of the converter 1 converter circuit with self-excited synchronous rectifier circuit for this creation. This creation uses a pulse-width-tuned electric power to switch a power electronic switch Q5, so that an output and an energy storage 1 ^^ are used by a first transformer Ή, a synchronous rectifier circuit 12 1 2 _ ^, , 1 4 is transmitted to a load 16. Wherein, the leakage terminal D of the synchronous rectifier circuit voltage transformer T1 secondary gamma field effect transistor 18 is connected to the first positive terminal (ρ), ~ terminal B, and the source terminal S is connected to a flywheel diode D The first transformer teaches that the negative terminal (N) of the flywheel diode D2 is connected to the other end A of the secondary side of I σ τ 1, and at the same time, the N-channel field effect power

Page 8 M254007 Creative Instructions (5) ------- Jingying electric power ί i8t control Λ terminal G through an electric, R and a capacitor c are connected to-residual effect on the source and: ^ flow Filtering electricity policy: shirt mountain + two A-connectors, change through _ '"c: Second, the parent flow power Ac is adjusted to flow #, and the AC power factor iiit is the current of the rippled DC power. DC Power Retransmission "is used to achieve and deregulate: ΐ15 as the improvement of the overall power system power factor *, road 15 improves the work requirements. The DC power corrects the power VCC via a power factor. 'After that, you can get the input voltage required for this creative work.' The energy storage 14 series includes,-the second variable-resistance R], then the f group coil T2 1, at least one energy storage Capacitors Cr and at least two special. And the induction coil L is the second winding T9 < secondary winding coil T22. At u, the two-pulse-width modulation controller 10 drives the power electronic switch Q5 to be turned ON (two): t power vcc is transmitted to the g ΐ through the primary side of the first transformer T1, and through the second transformer T2. At the same time, the primary winding coil T21 is stored at this time. At this time, the primary winding coil T21 of the second transformer T2 is generated in the secondary winding coil T 2 2 to generate electrical energy. The transistor 18 is turned on to form a power supply, and the power is supplied to the load! 6 uses. ) When the pulse width modulation controller 10 drives the electronic switch Q5 to turn off (OFF, the primary side of the first transformer T1 has no input power VCC power supply, because M254007 creation instructions (6) this first transformer τι twice The side system cannot supply power to the load 16. At this time, the primary side winding coil T2 1 of the second transformer T2 changes polarity and transmits the stored energy to the load 16 through the flywheel diode D2, so that the load 16 can continue Work without power off. The secondary winding T22 of the second transformer T2 also changes polarity at the same time, which drives the N-channel field effect transistor. 8 OFF (OFF). In the above description, when the PWM controller 〇 When the drive power electronic switch Q5 is on (0N) or off (〇FF), there is another secondary winding T22 of the second transformer τ2, which is connected to one of the backup power terminals of the pulse width modulation controller 丨 〇, It is used to provide a redundant power supply for the pulse width modulation controller. The third figure, please refer to the fourth figure, is the schematic diagram of the reverse conduction voltage and on current waveforms of the N-channel field effect transistor for this creation. 10 -tl 'The N-channel field-effect transistor system is in the cut-off (0FF) state, so no conduction current I c passes, and the n-channel field-effect transistor 18 has the reverse conduction voltage Vrrm between the drain terminal D and the source terminal S, which is the first. The voltage generated on the secondary side when the transformer τΐ is discharged is a decreasing voltage value. At this time, there is no loss of power consumption because no conduction current I c passes. At time t2-13, the N-channel field effect power The crystal 18 is in a conduction (0N) state, so a conduction current I c passes, and the reverse conduction voltage Vrrm between the N-channel field effect transistor drain terminal D and the source terminal s is near zero potential. At this time, Since the reverse conduction voltage Vrrm value is close to zero potential, as can be known from the above description, the N-channel field effect voltage used in this creation

M254007 4. Creation instructions (7) When the crystal 18 is switched between ON and OFF, the power loss consumed is extremely small, which can improve the power supply efficiency and reduce the operating temperature. In conjunction with the third picture, please refer to the fifth picture, which is a schematic diagram of the driving signal waveform of the N-channel field effect transistor 18 created at no load. In the case of no-load power supply, the electric energy induced by the secondary winding T22 of the second transformer T2 will be less than the critical driving voltage point of the N-channel field-effect transistor 18, and the N-channel field-effect transistor 18 cannot be turned on. . The electric energy induced by the secondary winding T2 2 of the second transformer T2 is the driving signal S 1 of the N-channel field effect transistor 18 under no load. In conjunction with the third figure, please refer to the sixth figure, which is not intended for the driving signal waveform of the N-channel field effect transistor created at full load for this creation. When the power supply is full load, the electric energy induced by the secondary winding T22 of the second transformer T2 will be greater than the critical driving electric point 5 of the N-channel field-effect transistor 18 and the N-channel field-effect transistor 18 will be turned on. Induced by the secondary winding T22 of the second transformer T2, the electric energy is the driving signal S2 of the N-channel field effect transistor 18 at a full load. Please refer to the third figure. This creative system can use the electric energy induced by the secondary winding coil T 2 2 of the second transformer T2 to provide the pulse width modulation controller 1 for use as the pulse width modulation controller 1 0 redundant power supply, and can still provide stable working power to the pulse width modulation controller 10 when no-load power supply is used. In addition, the pulse width modulation controller 10 will automatically reduce the frequency when no-load, thereby reducing the loss of the converter. As mentioned above, a forward power converter with a self-excited synchronous rectifier circuit is provided in the forward direction of the second transformer T 2

M254007 4. Creation instructions (8) The primary winding coil T2 1 establishes energy and uses the self-excitation of the second transformer T2 to make the secondary winding coil T2 2 of the second transformer T2 induce electric energy and transmit it to the N channel. The control terminal G of the field effect transistor 18 is used to drive the ON of the N-channel field effect transistor 18. Furthermore, in the case of no-load power supply, the induced energy of the secondary winding T 2 2 of the second transformer T 2 will be less than the critical driving voltage point of the N-channel field-effect transistor 18, so that the N-channel field-effect power Crystal 18 cannot be turned on. At the same time, a forward power converter with a self-excited synchronous rectifier circuit is created, which can use the electric energy induced by the secondary winding T22 of the second transformer T2 to provide the pulse width modulation controller 10 for use. , Becomes the backup power source of the PWM controller 10, and can still provide a stable working power to the PWM controller 10 when no-load power is supplied, so in addition to the PWM controller 1 0 is automatically reduced when no-load, in order to reduce the loss of the converter. Therefore, the main purpose of creating a forward power converter with a self-excited synchronous rectifier circuit is to replace the conventional diode with an N-channel field-effect transistor 18, and to use an induction coil to induce power during forward power supply. It is used to drive the N-channel field effect transistor to be turned on, thereby reducing the power consumption of the circuit and improving the working efficiency and power density. And in the case of no-load of the mains but the system is shut down, the minimum input power consumption is achieved to save energy, so the overall power loss is extremely small, and the input power required by regulations can be less than 1 W. However, the above description is only a detailed description and a drawing of one of the best specific embodiments of the present invention.

M254007

The M254007 diagram on page 13 is a simple illustration. The first diagram is a schematic diagram of a conventional forward power converter circuit. The second diagram is a reverse forward voltage and on current waveform diagram of a conventional forward power converter diode. Third The diagram is the schematic diagram of the forward power converter circuit with self-excited synchronous rectifier circuit. The fourth diagram is the reverse conduction voltage and conduction current waveform diagram of the N-channel field effect transistor.

The fifth diagram is the waveform of the driving signal of the N-channel field effect transistor created at no load, and the sixth diagram is the schematic diagram of the drive signal of the N-channel field effect transistor created at full load. Explanation of drawing number: Known: Q1 power switch T1 transformer D1 D2, D3 diode

Lit inductor C output capacitor U1 pulse width modulation controller Original works: 1 0 pulse width modulation controller 11 electromagnetic interference protection circuit 1 2 synchronous rectification circuit

Page 14 M254007 Brief description of the diagram 1 3 Rectifier wave circuit 1 4 Energy storage 1 5 Power factor correction circuit 1 6 Load 18N channel field effect transistor T1 First transformer T 2 Second transformer VCC input power Q5 power electronic switch D2 flywheel diode

Page 15

Claims (1)

M254007 V. Application for patent scope 1. A method with self-excitation using a pulse width modulation, so that the circuit and an input power and energy storage rectification circuit use the positive pole of the secondary of the first transformer, and the secondary side of the voltage transformer The other end passes through a resistor, and the source of the induction coil is extreme. • If the application is forward one second 3 • If the application is forward second 2 4. If the application is forward one second secondary side patent range power transformer to the patent range power supply to the secondary winding patent range type The forward power converter of the synchronous winding rectification circuit of the winding coil of the power transformer is a switching power of the controller driving a power electronic switch, which can be transmitted to a load through a first transformer and a synchronous rectification register; its characteristics are: The leakage terminal of the synchronous N-channel field effect transistor is connected to one end of the side, the source terminal is connected to a flywheel diode, the negative terminal of the flywheel diode is connected to the first transformer terminal, and the N-channel field The controller of the effect transistor and a capacitor connected to one end of an induction coil and the other end are connected to the self-excited synchronous rectifier circuit converter described in item 1 of the N-channel field effect transistor, wherein the energy storage device The system includes at least a primary winding and an energy storage capacitor. The self-excited synchronous rectifier circuit converter according to item 1, wherein the induction coil is a second transformer coil. The self-excited synchronous rectifier circuit converter according to item 1, wherein the PWM controller can be connected to a secondary winding, and a backup power source is obtained from the second transformer. Page 16