CN101777844B - Resonant converter with phase-shifted output routing - Google Patents

Abstract

The invention relates to a resonance converter with a phase shift output route, which comprises a resonance conversion circuit, a switching unit, a power conversion circuit and a main output circuit, wherein the resonance conversion circuit obtains input power and modulates the input power into at least one resonance power; at least one auxiliary output circuit connected with the power conversion circuit to obtain the converted power is provided with a bridge rectifier unit and a phase shift control unit, the phase shift control unit is electrically connected with the resonance control unit to obtain the resonance control signal and modulate the resonance control signal into a phase shift driving signal, and the bridge rectifier unit is controlled by the phase shift driving signal to modulate the converted power into the auxiliary output power. Thereby improving the conversion efficiency of the conventional circuit and improving the defect of cross regulation.

Description

Resonant converter with phase-shifted output routing

technical field

The present invention relates to a resonant converter with a phase-shift output route, a structure of a power conversion circuit, and in particular to a resonant converter with a phase-shift output route using resonance and phase-shift control technology.

Background technique

Nowadays, the laws and regulations of various countries have continuously improved the conversion efficiency requirements of power supplies. At present, the 80PLUS standard (standard) promulgated by Energy Star stipulates the efficiency of multi-output power supplies for computers and servers. The 80plus standard (standard ) is divided into four grades: 80plus E-star 4.0, 80plus bronze (bronze), 80plus silver (silver) and 80plus gold (gold). Among them, the 80plus gold medal (gold) requires the efficiency of the power supply to be 87%, 90% and 87% at 20%, 50% and 100% load respectively. The general structure of current computer and server power supply is PFC+multi-output DC/DC, in which the efficiency of PFC in low-level line (lowline) can usually reach 94%. The conversion efficiency of the DC converter is required to be greater than 96%. At the same time, it can be foreseen that with the further development of electronic products in the direction of miniaturization, there will be higher requirements for the power density of computer power supplies. It is a big challenge for suppliers of suppliers.

High efficiency, high voltage regulation accuracy, and small size are the three major requirements for high power density multi-output DC/DC converters (converters). At present, ATX does not have further requirements for volume reduction, so high efficiency and high Voltage regulation accuracy is the main goal of power supply design. The hold up time requirement of a computer power supply is an important factor that must be considered in power supply design. When there is input power, PFC converts the input power into an adjustable DC voltage (such as 400V). When the input power disappears, the power supply is required to maintain the output voltage for 20mS, and this 20mS is the hold uptime. During the hold up time, the 400V voltage output by the PFC is continuously reduced until the lowest voltage, the DC/DC is turned off, and the output voltage disappears. The output should remain stable during the hold up time, so the DC/DC is required to work in a certain input voltage range. The specific input voltage range is related to the capacitance and power of the capacitor, which can be expressed by the following formula:

$\mathrm{<span\; class="notranslate">\; E.</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; the\; bus</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; min</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>$

It can be seen from the above formula that the capacitance value of the capacitor is inversely proportional to the voltage range. Expanding the input voltage range can reduce the capacitor volume and increase the power density. A wider input voltage range will bring difficulties to topology selection and circuit design. This is a very important research topic at present.

The key to improving the conversion efficiency is to suppress the switching loss of the converter. In the existing conventional converters, when the current or voltage is high, switching (hard switching, hard switching) will cause high switching loss, so it is later improved to Or switching when the voltage drops (soft switching, softswitching), even switching at zero current or zero voltage state. Currently, there are several types of circuit topologies with higher conversion efficiency: active clamp forward (ACF) circuit, LLC circuit and dual active bridge (DAB) circuit. Please refer to FIG. 1 , which is a circuit structure diagram of a conventional active forward clamping circuit. The circuit structure and operation mode of the ACF circuit are well known in this technical field, so details are not repeated here. The ACF circuit can partially or fully realize the zero-voltage switching (ZVS) of the primary switching tube, so the efficiency is high; at the same time, the transformer core works in one or three quadrants, and the core utilization rate is high. However, the ACF circuit has several inherent disadvantages, such as: hard turn-off leads to large turn-off loss; to achieve complete ZVS, it is necessary to add additional inductance and reduce the excitation inductance, increasing the inductance will reduce the equivalent duty cycle, Reducing the excitation inductance will increase the excitation current, resulting in large copper loss and switch conduction loss; there is a cross regulation problem; it is difficult for ACF controlled by traditional pulse width modulation (Pulse Width Modulation, PWM) to meet high efficiency and wide voltage range operating requirements. Therefore, the efficiency of the ACF architecture cannot be made very high, but because of the realization of ZVS activation, its efficiency is higher than that of general PWM architectures such as dual-transistor forward and half-bridge circuits. On-semi's 250W ATX power supply based on ACF design can meet 80plus E-star 4.0, so that the efficiency of the power supply can be greater than 80% at 20%, 50% and 100% load.

At present, the LLC circuit has the most application prospect in the post-stage DC/DC. Please refer to FIG. 2, which is a circuit structure diagram of an existing conventional LLC circuit. The LLC circuit uses two L (inductors) and one The resonant circuit composed of C (capacitor) controls the cycle of an input power flowing to an LLC loop 302 through a set of switches 301, and the input power is sent to the secondary side by a transformer 303 after the gain of the LLC loop 302 Output, and a control chip 304 on the primary side generates a control pulse, and the control pulse is passed through a driver 305 to adjust the switching period of the switch 301. Please refer to FIGS. 3 and 4 for the waveforms of each node of the circuit shown in FIG. 2 As shown, Fig. 3 is a waveform diagram of the circuit node in Fig. 2, and Fig. 4 is a resonance characteristic curve of the circuit in Fig. 2 . The LLC circuit has the advantages of zero-voltage switching, small turn-off loss, wide operating voltage range without sacrificing the conversion efficiency when the input power is normal, the capacitance of the PFC capacitor can be reduced, and the volume can be reduced, thereby increasing the power density.

The dual active bridge (DAB) circuit applied to high-power DC/DC can achieve high power density. Please refer to Fig. 5, which is a structure diagram of an existing conventional dual-active bridge circuit, which includes two sets of full-bridge switches 301, an inductor and a transformer 303 for power isolation, and through The control chip 304 and the driver 305 control the action of the switch 301. Please refer to FIG. 6, which is the circuit node waveform diagram of FIG. The shift angle (Φ), the circuit architecture in Figure 5 can adjust the output gain (gain) by changing the phase shift angle and changing the switching frequency. Furthermore, zero-voltage switching can be achieved by controlling the conduction phase of the primary side and secondary side switches. And the output power is adjusted, and its characteristic is that the primary side and the secondary side switch can switch at zero voltage, and can work under the input of wide voltage range without sacrificing the efficiency during normal operation. Since the DAB circuit can realize zero-voltage switching of the secondary-side switching tube, it is more used in high-voltage output occasions requiring high efficiency. The inductance used to transmit energy in the DAB circuit is very small and can be realized by the leakage inductance of the transformer, so the DAB circuit can achieve high power density. For low-voltage output applications of computer power supplies, DAB circuits have larger turn-off losses than LLC circuits, but DAB circuits are easier to implement synchronous rectification than LLC circuits.

Because the LLC circuit has the characteristics of high conversion efficiency, the multi-output DC/DC converter (converter) based on LLC is a research hotspot. Several representative architectures are LLC+magnetic amplifier (magamp), as shown in Figure 7, which is an implementation state diagram of conventionally using a magnetic amplifier to adjust secondary output power; LLC uses transformer coupling to achieve multiple outputs, please refer to Figure 8 As shown, it is the implementation state diagram of conventionally adjusting the secondary output power according to the voltage ratio, LLC plus cascaded bucks, and multiple independent LLCs to achieve multiple outputs, etc. Each of these circuits has advantages and disadvantages, and each has its own application. Fig. 7 shows the circuit architecture of LLC+magnetic amplifier (magamp), which has a set of switches 301, an LLC loop 302, a transformer 303, a control chip 304 and a driver 305, the LLC loop 302 provides the main output, Moreover, the secondary side of the transformer 303 is further connected with auxiliary circuits such as two magnetic amplifiers 307 (magamp) and a control loop 306 to provide auxiliary output. The magnetic amplifier 307 (magamp) is controlled as a switch, and the function of the magnetic amplifier 307 (magamp) and its connected auxiliary circuit is equivalent to a buck circuit, and has the advantages of low cost, precise adjustment of each output, and simple control. But its main disadvantages are as follows: 1. The magnetic saturation inductor has core loss and copper loss; 2. The conduction loss and reverse recovery loss of the rectifier diode; 3. The synchronous rectification of the LLC circuit is greatly affected by the magnetic saturation amplifier circuit; 4. .The inherent dead zone effect of the magnetic saturation circuit limits its working frequency. Therefore the LLC+magnetic amplifier (magamp) circuit cannot achieve high efficiency.

Please refer to Fig. 8, for LLC utilizes transformer coupling to realize multi-channel output, wherein a plurality of switching switches 301 are connected to an LLC loop 302, a circuit structure of a transformer 303 is the same as the previous prior art, but through a specific gravity The distribution circuit 92 and a coupling element 93 adjust the duty cycle of a driver 305. The biggest problem with this architecture is cross-regulation. Firstly, the ratio of turns of the secondary side coil cannot be completely equal to the ratio of the output voltage, which will affect the regulation accuracy. Secondly, if only the main output is controlled, the auxiliary output is only adjusted by coupling, and the accuracy is very poor, which can be improved by using weighted control, but the weighted control is to share the error between the two outputs, so that each channel cannot be adjusted accurately, so this This structure can only be used in occasions that do not require high voltage regulation. In order to improve cross-regulation, using multiple independent LLC circuits can achieve high efficiency and precise regulation, but the cost and volume are too large; if the LLC circuit is used as the main output line and the back-end is connected to the main output with a buck converter (buckconverter) The lines form secondary output lines, although each output line can be precisely adjusted, but reduces the overall conversion efficiency.

This shows that above-mentioned existing each circuit obviously still has inconvenience and defect in structure and use, and urgently needs to be further improved. In order to solve the above-mentioned problems, the relevant manufacturers have tried their best to find a solution, but no suitable design has been developed for a long time, and the general products do not have a suitable structure to solve the above-mentioned problems. This is obviously the relevant industry. urgent problem to be solved. Therefore, how to create a resonant converter with a new structure and a phase-shift output route is one of the current important research and development topics, and it has also become a goal that the industry needs to improve.

In view of the advantages and disadvantages of the above circuits, the present invention proposes a multi-output DC/DC converter (converter) architecture with low cost, high power density, and high voltage regulation precision. This architecture still uses LLC as the main output and DAB as the auxiliary output. It combines the advantages of high efficiency and small size of LLC and DAB. The resonant inductance of LLC and the inductance of DAB for energy transmission can be realized by transformer leakage inductance, so it can be realized High power density, and each output can be adjusted independently to achieve high voltage regulation accuracy.

Contents of the invention

The purpose of the present invention is to overcome the defects that the existing known circuit structures may be difficult to achieve the required goals, and provide a resonant converter with a new structure with a phase shift output line. The technical problem to be solved is to improve its circuit structure , to achieve the beneficial effects of improving conversion efficiency and reducing loss, and having good interleaving adjustment capability, which is very suitable for practical use.

The purpose of the present invention and the solution to its technical problems are achieved by adopting the following technical solutions. According to the present invention, a resonant converter with a phase-shifted output line is proposed, which includes a resonant conversion circuit that obtains an input power and modulates it into at least one resonant power, and a conduction period that switches the input power through the resonant conversion circuit A switching unit, a power conversion circuit that modulates the resonant power to output a converted power, wherein the resonant conversion circuit includes a resonant capacitor, a resonant inductance and a parallel inductance, the parallel inductance is connected in parallel with the power conversion circuit and one end of the parallel inductance The resonant inductor is connected, and the resonant converter further includes: a main output circuit connected to the power conversion circuit to modulate the converted power into a main output power, and a resonant control unit is electrically connected to the main output power of the main output circuit A resonance control signal is generated by capturing a feedback signal, the switching unit is driven by the resonance control signal; and at least one secondary output circuit connected to the power conversion circuit to obtain the converted power, the secondary output circuit has a bridge rectification unit and a phase shift control unit, the phase shift control unit is electrically connected to the resonance control unit to obtain the resonance control signal and modulate it into a phase shift drive signal, and the bridge rectifier unit is controlled by the phase shift drive signal to modulate the Convert electric power to a pair of output electric power.

The purpose of the present invention and its technical problems can also be further realized by adopting the following technical measures.

The aforementioned resonant converter with a phase-shift output line, wherein the power conversion circuit is a transformer, the transformer has a primary side coil and a plurality of independent secondary side coils, wherein the plurality of secondary side coils are respectively connected to on the main output circuit and a plurality of auxiliary output circuits.

In the aforementioned resonant converter with a phase-shifted output line, wherein the plurality of secondary side coils have different numbers of turns, so that at least one of the secondary output power provided by the secondary output circuit has the same phase as the main output power. different voltage levels.

In the aforesaid resonant converter with a phase-shifted output line, the power conversion circuit includes more than one transformer, and a main transformer is defined in the more than one transformer to connect to the main output circuit and output the main output power.

In the aforesaid resonant converter with a phase-shifted output circuit, the power conversion circuit further includes at least one secondary transformer different from the main transformer, and the secondary side of the secondary transformer is connected to at least one secondary output circuit.

In the aforementioned resonant converter with a phase-shift output line, the primary side of the secondary transformer is connected to the resonant conversion circuit.

In the aforementioned resonant converter with a phase-shift output line, the primary side of the auxiliary transformer is connected in parallel with the primary side of the main transformer.

The aforementioned resonant converter with a phase-shift output line, wherein the primary side of the secondary transformer is connected to the switching unit and connected in parallel with the resonant conversion circuit, and a capacitive element is connected between the primary side of the secondary transformer and the switching unit .

In the aforesaid resonant converter with a phase-shift output line, the phase-shift driving signal is modulated by the phase-shift control unit to have a phase difference with the resonant control signal.

In the aforesaid resonant converter with a phase-shift output line, the phase-shift control unit extracts a second feedback signal from the secondary output power to modulate the time interval of the phase-shift driving signal.

In the aforesaid resonant converter with a phase-shift output line, the switching unit is a full-bridge loop formed by a plurality of switching elements, and each switching element is driven by a resonance control signal generated by the resonance control unit.

In the aforesaid resonant converter with a phase-shift output line, the switching unit is a half-bridge circuit formed by a plurality of switching elements, and each switching element is driven by a resonance control signal generated by the resonance control unit.

In the aforesaid resonant converter with a phase-shifted output line, the switching element of the switching unit is connected in parallel with the corresponding capacitive element.

In the aforesaid resonant converter with a phase-shift output line, the main output circuit has a synchronous rectification unit controlled by the resonance control signal, and the synchronous rectification unit is connected to the power conversion circuit.

In the aforesaid resonant converter with a phase-shifted output line, the synchronous rectification unit is a full-bridge rectification circuit composed of a plurality of switching elements.

In the aforementioned resonant converter with a phase-shift output line, the synchronous rectification unit is a circuit with a center tap formed by a plurality of switching elements.

In the aforementioned resonant converter with a phase-shifted output line, the bridge rectifier unit is a full bridge rectifier circuit composed of a plurality of switching elements.

In the aforementioned resonant converter with a phase-shift output line, the bridge rectification unit is a half-bridge rectification circuit composed of a plurality of switching elements.

In the aforesaid resonant converter with a phase-shift output line, a clamping capacitor is connected in series between the switching elements of the bridge rectifier to adjust the voltage level output by the bridge rectifier.

Compared with the prior art, the present invention has obvious advantages and beneficial effects. As can be seen from the above, in order to achieve the above object, the present invention provides a resonant converter with a phase-shifted output circuit, which includes a resonant conversion circuit that obtains an input power and modulates it into at least one resonant power, and a switching circuit for switching the input power through The switching unit of the conduction period of the resonant conversion circuit, a power conversion circuit that modulates the resonant power and outputs a converted power, wherein the resonant conversion circuit includes a resonant capacitor, a resonant inductance and a parallel inductance, the parallel inductance and the power conversion The circuit is connected in parallel and one end of the parallel inductor is connected to the resonant inductor, and the resonant converter further includes a main output circuit and at least one secondary output circuit, the main output circuit is connected to the power conversion circuit and modulates the converted power into a main output power , and a resonance control unit is electrically connected to the main output power of the main output circuit to capture a feedback signal to generate a resonance control signal, the switching unit is driven by the resonance control signal; the secondary output circuit is connected to the power conversion circuit to obtain For the converted power, the secondary output circuit has a bridge rectifier unit and a phase shift control unit, the phase shift control unit is electrically connected to the resonance control unit to obtain the resonance control signal and modulate it into a phase shift drive signal, and the The bridge rectifier unit is controlled by the phase-shift driving signal to modulate the converted power into an output power; wherein the above-mentioned resonant conversion circuit has a resonant capacitor, a resonant inductance and a parallel inductance connected in parallel with the power conversion circuit to form One has an LLC resonant circuit, and the secondary output circuit is controlled by phase shift. With the above-mentioned circuit structure, the conversion efficiency can be further improved, the loss can be reduced, and the input power can not sacrifice normal operation under a wide range of voltage tolerance. When the conversion efficiency, and achieve LLC circuit can provide the advantages of multiple output power.

With the above technical solution, the resonant converter with phase shift output route of the present invention has at least the following advantages and beneficial effects:

1. The present invention can combine LLC circuit and phase shift control to improve conversion efficiency.

2. The present invention can operate without sacrificing the conversion efficiency in normal operation under a wide range of input power voltage tolerance.

3. The present invention provides multiple outputs and can achieve high voltage stabilization accuracy.

To sum up, the present invention relates to a resonant converter with a phase-shifted output circuit, which includes a resonant conversion circuit that obtains an input power and modulates it into at least one resonant power, and switches the input power through the resonant conversion circuit. A switching unit for the conduction period of the circuit, a power conversion circuit that modulates the resonant power and outputs a converted power, and further includes a main output circuit and at least one secondary output circuit, the main output circuit is connected to the power conversion circuit and modulates the converted power as A main output power, and a resonance control unit is electrically connected to the main output circuit to capture a feedback signal to generate a resonance control signal, the secondary output circuit is connected to the power conversion circuit to obtain the converted power, and a phase shift control is set The unit obtains the resonance control signal and modulates it into a phase-shift driving signal, and the secondary output circuit is controlled by the phase-shift driving signal to modulate the converted power into a secondary output power; thereby improving the conversion efficiency of the existing conventional circuit, Improve the lack of cross-regulation. The present invention has significant progress in technology, and has obvious positive effects, and is a novel, progressive and practical new design.

The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the following preferred embodiments are specifically cited below, and are described in detail as follows in conjunction with the accompanying drawings.

Description of drawings

FIG. 1 is a circuit structure diagram of a conventional active forward clamping circuit.

FIG. 2 is a circuit structure diagram of a conventional LLC circuit.

FIG. 3 is a waveform diagram of circuit nodes in FIG. 2 .

Fig. 4 is the resonance characteristic curve of Fig. 2 circuit.

FIG. 5 is a structure diagram of a conventional dual-active bridge circuit.

FIG. 6 is a waveform diagram of circuit nodes in FIG. 5 .

FIG. 7 is an implementation state diagram of using a magnetic amplifier to adjust auxiliary output power in the prior art.

FIG. 8 is an implementation state diagram of adjusting the auxiliary output power according to the voltage ratio in the prior art.

Fig. 9 is a schematic diagram of the implementation state of the first preferred embodiment of the present invention.

Fig. 10 is a schematic diagram of the implementation state of the second preferred embodiment of the present invention.

Fig. 11 is a schematic diagram of the implementation state of the third preferred embodiment of the present invention.

FIG. 12 is a power waveform diagram indicated in FIG. 11 .

Fig. 13 is a schematic diagram of the implementation state of the fourth preferred embodiment of the present invention.

FIG. 14 is a waveform diagram of circuit nodes in FIG. 13 .

Fig. 15 is a schematic diagram of the implementation state of the fifth preferred embodiment of the present invention.

Fig. 16 is a schematic diagram of the implementation state of the sixth preferred embodiment of the present invention.

Detailed ways

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the specific implementation and structure of the resonant converter with phase shift output route proposed according to the present invention will be described below in conjunction with the accompanying drawings and preferred embodiments. , features and their effects are described in detail below.

The aforementioned and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings. Through the description of the specific implementation mode, a more in-depth and specific understanding of the technical means and effects adopted by the present invention to achieve the intended purpose can be obtained. However, the accompanying drawings are only for reference and description, and are not used to explain the present invention. be restricted.

Please refer to FIG. 9 for the circuit structure of the present invention, which is a schematic diagram of the implementation state of the first preferred embodiment of the present invention. A resonant converter with a phase-shifted output line in the preferred embodiment of the present invention includes a switching unit 3. A resonant conversion circuit 1, a power conversion circuit 2,

The power conversion circuit 2 is a transformer, and the transformer is wound with a primary side coil 201 and two independent secondary side coils 202, 203; after the circuit is connected to a power source 101 to obtain an input power, the switching unit 3 To switch the conduction period of the input power passing through the resonant conversion circuit 1, the switching unit 3 is a bridge circuit composed of a plurality of switching elements, and controls the input power to flow to the resonant conversion circuit 1 by interleaved conduction of a plurality of switching elements cycle,

The resonant conversion circuit 1 includes a resonant capacitor 11, a resonant inductance 12 and a parallel inductance 13, the parallel inductance 13 is connected in parallel with the power conversion circuit 2 and one end of the parallel inductance 13 is connected to the resonant inductance 12, through the resonant conversion The resonant characteristic of the circuit 1 itself modulates the input power to form a resonant power and sends it to the power conversion circuit 2, and the power conversion circuit 2 modulates the resonant power to output a converted power;

The switching unit 3 can be a half-bridge circuit composed of two switching elements as shown in the figure, and the switching unit 3 can be connected in parallel with corresponding capacitive elements (C1, C2 in the figure) beside the switching elements to Bearing part of the DC voltage can reduce the DC voltage borne by the resonant capacitor 11, and further, a capacitor element with a lower withstand voltage (such as MLCC, multilayer ceramic capacitor) can be selected;

The resonant converter further includes a main output circuit 10 and at least one secondary output circuit 20, wherein:

The main output circuit 10 has a synchronous rectification unit 7 connected to the secondary side coil 202 of the power conversion circuit 2 to obtain the converted power, and is modulated into a main output power 102 through the switching of a synchronous rectification unit 7, and a The resonance control unit 4 is electrically connected to the main output power 102 of the main output circuit 10, the resonance control unit 4 captures the first feedback signal generated by the main output power 102 and generates a resonance control signal according to the first feedback signal, The resonance control signal drives the synchronous rectification unit 7 through a driver 52, thereby adjusting the switching period of the synchronous rectification unit 7; the resonance control signal is modulated by a pulse modulation unit 54 to form a pulse-type control signal, and passed through An auxiliary coil 91 transmits the control signal to another driver 51, which provides power to drive the switching unit 3 through the driver 51, so that each switching element of the switching unit 3 is subjected to the resonance control signal generated by the resonance control unit 4 driven to control the period of passage of the input power;

At the same time, the secondary output circuit 20 is connected to another independent secondary side coil 203, the secondary output circuit 20 has a bridge rectifier unit 8 electrically connected to the secondary side coil 203, and a bridge rectifier unit 8 electrically connected to the resonant The control unit 4 obtains the phase shift control unit 6 of the resonance control signal, the bridge rectifier unit 8 is also composed of a plurality of switching elements, and the phase shift control unit 6 obtains the resonance control signal and modulates to generate a phase shift drive signal, there is a phase difference between the phase shift drive signal and the resonance control signal, the phase shift drive signal also drives the bridge rectifier unit 8 through a driver 53, and the bridge rectifier unit 8 is controlled by the phase shift drive signal Modulate the converted power to form a secondary output power 103, the phase shift control unit 6 extracts a second feedback signal from the secondary output power 103 to modulate the time interval of the phase shift driving signal, so that the secondary output circuit 20 can use The phase-shift control method achieves the effects of changing the output gain, zero-voltage switching, and reducing the turn-off loss.

The circuit architecture described in FIG. 9 is the most basic implementation form of the present invention, and the present invention further includes a form with multiple secondary output circuits 20. Please refer to FIG. 10, which is the implementation state of the second preferred embodiment of the present invention. Schematic diagram, wherein the power conversion circuit 2 is still a transformer wound with multiple coils, the transformer has a primary side coil 201 and a plurality of independent secondary side coils 202, 203, 204, wherein the secondary side coil 202 is connected to The main output circuit 10, the other secondary side coils 203, 204 are respectively connected to a plurality of secondary output circuits 20, the front end of the power conversion circuit 2 (primary side of the transformer) is still controlled by the switching unit 3 and the input power flows to the The period of the resonant conversion circuit 1, and the switching unit 3 shown in Figure 10 is the most basic half-bridge circuit form, and the action of the switching unit 3 is also controlled by the resonance control signal of the resonance control unit 4 (through the The pulse modulation unit 54, the auxiliary coil 91 and the driver 51 are transmitted to the switching unit 3), and the main output circuit 10 at the rear end of the power conversion circuit 2 (the secondary side of the transformer) is also the same as the structure shown in FIG. 9 The same, and the implementation state shown in FIG. 10 is that multiple secondary side coils 203, 204 are connected to multiple secondary output circuits 20 through the transformer to form multiple secondary output power 103, and the multiple secondary output power 103 At least one of them has a different voltage level from the main output power 102, and the plurality of secondary output power 103 may have a different voltage level, and each secondary output power 103 is passed through an independent phase shift control unit 6 and The driver 53 independently outputs multiple sets of secondary output power 103 with the same or different voltage levels; therefore, the power architecture can set the output quantity and voltage according to the needs of the power supply; The switching unit 3 in the state, the synchronous rectification unit 7 and the bridge rectification unit 8 of the secondary output circuit 20 can be respectively a full-bridge or half-bridge circuit composed of a plurality of switching elements, and the synchronous rectification unit 7 can be a For a circuit with a center tap (as shown in FIG. 9 ), the technology of obtaining power from the center tap between multiple switching elements is well known to those skilled in the art, so only FIG. 9 is used as a representative.

Please refer again to Fig. 11, which is a schematic diagram of the implementation state of the third preferred embodiment of the present invention. The switching unit 3 and the bridge rectifier unit 8 shown in this figure are all half-bridge forms, and the one shown in Fig. 11 Please refer to FIG. 12 for the marked power waveforms, which is the power waveform diagram marked in FIG. The phase shift angle (Φ) can adjust the output gain (gain); please refer to Figure 13 again, which is a schematic diagram of the implementation state of the fourth preferred embodiment of the present invention, and the circuit structure shown in Figure 13 is substantially the same as that of Figure 11 , but a clamp capacitor 81 is further set in the bridge rectifier unit 8 of the secondary output circuit 20 of FIG. Please refer to FIG. 14 for the output level of the electric power 103 , which is the waveform diagram of the circuit node in FIG. 13 . The operation principle of the clamping capacitor 81 is well known to those skilled in the art, so it will not be repeated here.

Please refer to FIG. 15 , which is a schematic diagram of the implementation state of the fifth preferred embodiment of the present invention. The power conversion circuit 2 in the above circuit can also include more than one transformer, and define a main transformer 21 in more than one transformer. The remaining transformers are defined as one or more auxiliary transformers 22, wherein the main transformer 21 and the auxiliary transformer 22 all have a primary side coil 211, 221 and a secondary side coil 212, 222, the primary side coil of the main transformer 21 211 is connected to the resonant conversion circuit 1, and the parallel inductor 13 is connected in parallel with the primary side coil 211, the secondary side coil 212 of the main transformer 21 is connected to the main output circuit 10; the primary side 221 of the auxiliary transformer 22 is connected to the The resonant inductor 12 is connected in parallel with the parallel inductor 13, the secondary side coil 222 of the secondary transformer 22 is connected to at least one secondary output circuit 20, and the bridge rectifier unit 8 of the secondary output circuit 20 is based on the phase shift control unit 6 and the For the control of the driver 53, the phase-shift control unit 6, in addition to being connected to the resonance control unit 4, also extracts a second feedback signal from the secondary output power 103 to modulate the time interval of the phase-shift drive signal; and a multi-transformer The form can also be as shown in Figure 16, which is a schematic diagram of the implementation state of the sixth preferred embodiment of the present invention, and also distinguishes at least one main transformer 21 and at least one secondary transformer 22 among the plurality of transformers (the main transformer 21 and the secondary transformer 22 in Figure 16 The auxiliary transformer 22 is all taken as an example), its main circuit structure is all the same as that of FIG. 15, and the difference between the embodiment of FIG. 16 and FIG. and connected in parallel with the resonant conversion circuit 1, and a capacitive element (Cb1) is connected between the primary side coil 221 of the secondary transformer 22 and the switching unit 3, and the secondary output circuit connected to the secondary side coil 222 of the secondary transformer 22 The output of 20 is controlled by the phase shift control unit 6, wherein the phase shift control unit 6 extracts a second feedback signal from the secondary output power 103 to modulate the phase shift drive signal in addition to being connected to the resonance control unit 4 time interval.

As mentioned above, the beneficial effect that the above circuit can achieve is: it not only has the high efficiency of the LLC circuit, but also can effectively adjust the power of multiple output circuits through phase shift control. In this case, the LLC circuit and the dual active bridge (Dual active bridge, DAB) circuit, and each auxiliary output circuit can be independently controlled by the phase shift control unit 6 to achieve precise adjustment, with high conversion efficiency of LLC circuit, relatively wide input voltage range, and dual active bridge type The (dual activebridge) circuit's excellent post regulation (POST REGULATION) capability achieves high overall conversion efficiency and has the advantages of precise regulation.

Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention, wherein, the above-mentioned switching unit 3 can be a full-bridge circuit, a half-bridge circuit, or a half-bridge circuit with a capacitive element. two types (the above three types are all rectification circuits well known to those skilled in the art), and the bridge rectifier unit 8 can also be matched with a full-bridge circuit, a half-bridge circuit or a half-bridge circuit A clamping capacitor 81; In addition, although the above-mentioned parallel inductance 13 is shown in the figure as an independent inductance element, the resonant conversion circuit 1 can be regarded as the parallel inductance 13 by using the equivalent exciting inductance of the main transformer 21, also That is, the resonant conversion circuit 1 does not need to be connected to a physical inductance element, but can achieve the expected effect by being connected to the main transformer 21 and resonating with the equivalent exciting inductance of the main transformer 21; any technical personnel familiar with this profession, Without departing from the scope of the technical solution of the present invention, when the technical content disclosed above can be used to make some changes or modifications to equivalent embodiments of equivalent changes, but all the content that does not depart from the technical solution of the present invention, according to the technical essence of the present invention Any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the technical solutions of the present invention.

Claims (19)

1. A resonant converter with a phase-shifted output line, which includes a resonant conversion circuit (1) that obtains an input power and modulates it into at least one resonant power, a switch that switches the input power through the resonant conversion circuit (1) A switching unit (3) for the conduction period, a power conversion circuit (2) that modulates the resonant power and outputs a converted power, wherein the resonant conversion circuit (1) includes a resonant capacitor (11), a resonant inductance (12) and A parallel inductor (13), the parallel inductor (13) is connected in parallel with the power conversion circuit (2) and one end of the parallel inductor (13) is connected to the resonant inductor (12), and it is characterized in that the resonant converter further includes: A main output circuit (10) connected to the power conversion circuit (2) to modulate the converted power into a main output power (102), and a resonance control unit (4) electrically connected to the main output circuit (10) outputting power (102) to capture a feedback signal to generate a resonance control signal, the switching unit (3) is driven by the resonance control signal; and At least one secondary output circuit (20) connected to the power conversion circuit (2) to obtain the converted power, the secondary output circuit (20) has a bridge rectifier unit (8) and a phase shift control unit (6), the phase The shift control unit (6) is electrically connected to the resonance control unit (4) to obtain the resonance control signal and modulate it into a phase shift drive signal, and the bridge rectifier unit (8) is controlled by the phase shift drive signal to modulate the The electric power is converted into an output electric power (103). 2. The resonant converter with a phase-shift output line according to claim 1, wherein said power conversion circuit (2) is a transformer having a primary side coil (201) and a plurality of Independent secondary side coils (202, 203, 204), wherein multiple secondary side coils (202, 203, 204) are respectively connected to the main output circuit (10) and multiple secondary output circuits (20). 3. The resonant converter with a phase-shifted output circuit according to claim 2, wherein said plurality of secondary side coils (203, 204) have different numbers of turns, so that the secondary output circuit ( 20) At least one of the secondary output powers (103) provided has a different voltage level from the main output power (102). 4. The resonant converter with a phase-shift output line according to claim 1, wherein said power conversion circuit (2) includes more than one transformer, and defines a main transformer ( 21) Connect the main output circuit (10) to output the main output power (102). 5. The resonant converter with a phase-shift output line according to claim 4, wherein said power conversion circuit (2) further comprises at least one auxiliary transformer (22) different from the main transformer (21) ), and the secondary side of the secondary transformer (22) is connected to at least one secondary output circuit (20). 6. The resonant converter with a phase-shift output line according to claim 5, wherein the primary side of the secondary transformer (22) is connected to the resonant conversion circuit (1). 7. The resonant converter with a phase-shift output line according to claim 5, wherein the primary side of the auxiliary transformer (22) is connected in parallel with the primary side of the main transformer (21). 8. The resonant converter with phase-shift output line according to claim 5, characterized in that the primary side of the secondary transformer (22) is connected to the switching unit (3) and connected to the resonant conversion circuit (1) connected in parallel, and a capacitive element is connected between the primary side of the secondary transformer (22) and the switching unit (3). 9. The resonant converter with a phase-shift output line according to claim 1, wherein said phase-shift drive signal is modulated by the phase-shift control unit (6) and has a phase difference with the resonance control signal . 10. The resonant converter with a phase shift output line according to claim 1, wherein said phase shift control unit (6) extracts a second feedback signal from the secondary output power (103) to modulate This phase shifts the timing of the drive signal. 11. The resonant converter with phase-shift output line according to claim 1, characterized in that the switching unit (3) is a full-bridge loop formed by a plurality of switching elements, and each switching element is affected by The resonance control signal generated by the resonance control unit (4) is driven. 12. The resonant converter with a phase-shift output line according to claim 1, wherein the switching unit (3) is a half-bridge circuit formed by a plurality of switching elements, and each switching element is affected by The resonance control signal generated by the resonance control unit (4) is driven. 13. The resonant converter with a phase-shift output line according to claim 12, wherein the switching element of the switching unit (3) is connected in parallel with the corresponding capacitive element. 14. The resonant converter with a phase-shift output line according to claim 1, wherein said main output circuit (10) has a synchronous rectification unit (7) controlled by the resonant control signal, the The synchronous rectification unit (7) is connected to the power conversion circuit (2). 15. The resonant converter with a phase-shift output line according to claim 14, wherein the synchronous rectification unit (7) is a full-bridge rectification circuit composed of a plurality of switching elements. 16. The resonant converter with a phase-shift output line according to claim 14, wherein the synchronous rectification unit (7) is a circuit with a center tap formed by a plurality of switching elements. 17. The resonant converter with a phase shift output line according to claim 1, wherein said bridge rectification unit (8) is a full bridge rectification circuit formed by a plurality of switching elements. 18. The resonant converter with a phase-shift output line according to claim 1, wherein the bridge rectification unit (8) is a half-bridge rectification circuit composed of a plurality of switching elements. 19. The resonant converter with a phase shift output line according to claim 18, characterized in that a clamping capacitor (81) is connected in series between the switching elements of the bridge rectifier unit (8) to adjust the The voltage level output by the bridge rectifier unit (8).

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