Power converter

Abstract

A power converter includes a primary side rectification filter circuit, an AC to DC converter, a DC to DC converter, a primary side controller, a secondary side rectification controller, and a secondary side feedback controller. The primary side rectification filter circuit receives an input voltage and rectifies and filters the input voltage to output a regulated input voltage. The AC to DC converter receives the regulated input voltage. The primary side controller provides a first control signal to control the AC to DC converter to convert the regulated input voltage to a DC input voltage and provides a second control signal to control the DC to DC converter. The secondary side rectification controller provides a third control signal to control the DC to DC converter to convert the DC input voltage to a converted voltage based on a gain condition to power a load. The secondary side feedback controller receives a load power demand signal provided by the load to control operation of the primary side controller and the secondary side rectification controller.

Description

Technical Field

[0001] This invention relates to a power converter, and more particularly to a power converter operable in a half-bridge or full-bridge circuit topology for providing multiple sets of output voltages of different magnitudes. Background Technology

[0002] For power supplies with a power rating greater than 100 watts, a PFC+LLC topology is typically used. This is mainly because LLC has zero-voltage switching characteristics, which allows the power supply to operate at higher frequencies, thereby reducing the size of the magnetic components and the overall product size.

[0003] The PFC architecture, as described above, with a PFC as the first stage followed by an LLC as the second stage, is a common power supply design. However, with the rapid advancement of technology and the proliferation of 3C products, the required voltages vary, making power supply specifications with different output voltages increasingly essential. Since the optimal operating point for LLC efficiency is at its resonant frequency, maintaining a stable input and output voltage at this frequency is crucial. Therefore, LLC is usually not the optimal solution for a single output voltage.

[0004] Therefore, how to design a power converter to solve the problems and technical bottlenecks of the existing technology is an important research topic for the inventors of this case. Summary of the Invention

[0005] The purpose of this invention is to provide a power converter that solves the problems of the prior art.

[0006] To achieve the aforementioned objectives, the power converter proposed in this invention includes a primary-side rectifier and filter circuit, an AC-to-DC converter, a DC-to-DC converter, a primary-side controller, a secondary-side rectifier controller, and a secondary-side feedback controller. The primary-side rectifier and filter circuit receives the input voltage and rectifies and filters the input voltage to output an adjusted input voltage. The AC-to-DC converter is coupled to the primary-side rectifier and filter circuit and receives the adjusted input voltage. The DC-to-DC converter is coupled to the AC-to-DC converter. The primary-side controller is coupled to the AC-to-DC converter and the DC-to-DC converter, providing a first control signal to control the AC-to-DC converter to convert the adjusted input voltage to a DC input voltage, and providing a second control signal to control the DC-to-DC converter. The secondary-side rectifier controller is coupled to the DC-to-DC converter and provides a third control signal to control the DC-to-DC converter to convert the DC input voltage to a converted voltage based on gain conditions to supply power to the load. The secondary-side feedback controller is coupled to the primary-side controller and the secondary-side rectifier controller, and receives a load power demand signal from the load to control the operation of the primary-side controller and the secondary-side rectifier controller.

[0007] In one embodiment, the secondary-side feedback controller provides a feedback control signal, including an AC / DC feedback control signal and a DC / DC feedback control signal, to the primary-side controller, and provides a rectification control signal to the secondary-side rectifier controller. The primary-side controller controls the AC-to-DC converter according to the AC / DC feedback control signal, controls the DC-to-DC converter according to the DC / DC feedback control signal, and controls the secondary-side rectifier controller and adjusts the gain conditions according to the rectification control signal.

[0008] In one embodiment, the DC-to-DC converter includes a primary-side isolation circuit and a secondary-side isolation circuit. The primary-side isolation circuit is coupled to the AC-to-DC converter and a primary-side controller to receive a second control signal and a DC input voltage. The secondary-side isolation circuit is coupled to a secondary-side rectifier controller to isolate the converted DC input voltage.

[0009] In one embodiment, the primary-side isolation circuit includes a bridge switching circuit and a resonant circuit. The secondary-side isolation circuit includes a bridge synchronous rectification circuit and a buck converter circuit.

[0010] In one embodiment, the bridge switching circuit includes an upper switch and a lower switch. A first terminal of the upper switch is coupled to an AC-to-DC converter. A first terminal of the lower switch is coupled to a second terminal of the upper switch and a resonant circuit. A primary-side controller provides a second control signal to control the upper and lower switches.

[0011] In one embodiment, the bridge synchronous rectifier circuit includes a first switch, a second switch, a third switch, and a fourth switch; a first main resonant inductor and a second main resonant inductor; and a first auxiliary resonant inductor and a second auxiliary resonant inductor. A first terminal of the first auxiliary resonant inductor is coupled to a second terminal of the first switch, and a second terminal of the first auxiliary resonant inductor is coupled to a first terminal of the second switch and a second terminal of the first main resonant inductor. A first terminal of the second auxiliary resonant inductor is coupled to a second terminal of the third switch, and a second terminal of the second auxiliary resonant inductor is coupled to a first terminal of the fourth switch and a first terminal of the second main resonant inductor. A first terminal of the first main resonant inductor is coupled to a second terminal of the second main resonant inductor. A first terminal of the third switch is coupled to a first terminal of the first switch and a buck converter circuit; a second terminal of the fourth switch is coupled to a second terminal of the second switch and a buck converter circuit. A secondary-side rectifier controller provides a third control signal to control the first, second, third, and fourth switches.

[0012] In one embodiment, the bridge synchronous rectifier circuit further includes a first capacitor and a second capacitor. A first terminal of the first capacitor is coupled to a third switch. A first terminal of the second capacitor is coupled to a second terminal of the first capacitor, and a second terminal of the second capacitor is coupled to a fourth switch.

[0013] In one embodiment, the buck converter circuit includes a fifth switch, a sixth switch, a diode, an inductor, and a capacitor. The first terminal of the fifth switch is coupled to the first terminal of the third switch. The first terminal of the sixth switch is coupled between the first terminal of the first main resonant inductor and the second terminal of the second main resonant inductor, and the second terminal of the sixth switch is coupled to the second terminal of the fifth switch. The cathode of the diode is coupled to the second terminals of the fifth and sixth switches. The first terminal of the inductor is coupled to the cathode of the diode. The first terminal of the capacitor is coupled to the second terminal of the inductor, and the second terminal of the capacitor is coupled to the anode of the diode and the second terminal of the fourth switch.

[0014] In one embodiment, when the conversion voltage is the first voltage, the first switch and the third switch are turned off, and the second switch and the fourth switch switch to turn on, thereby energizing the first main resonant inductor or the second main resonant inductor.

[0015] In one embodiment, when the second switch is turned on, a first magnetic excitation path is formed, comprising the second switch, a first main resonant inductor, and a buck converter circuit, which excites the first main resonant inductor. When the fourth switch is turned on, a second magnetic excitation path is formed, comprising the fourth switch, a second main resonant inductor, and a buck converter circuit, which excites the second main resonant inductor.

[0016] In one embodiment, when the conversion voltage is the first voltage, the second switch and the fourth switch are turned off, and the first switch and the third switch switch to conduct, thereby energizing the first main resonant inductor or the second main resonant inductor.

[0017] In one embodiment, when the first switch is turned on, a third magnetic excitation path is formed, comprising the first switch, a first main resonant inductor, and a buck converter circuit, which excites the first main resonant inductor. When the third switch is turned on, a fourth magnetic excitation path is formed, comprising the third switch, a second main resonant inductor, and a buck converter circuit, which excites the second main resonant inductor.

[0018] In one embodiment, when the conversion voltage is the second voltage, the first switch and the fourth switch are simultaneously turned on and off, the second switch and the third switch are simultaneously turned on and off, and the first switch and the second switch switch on and off to excite the first main resonant inductor and the second main resonant inductor.

[0019] In one embodiment, when the first switch and the fourth switch are simultaneously turned on, the first magnetic excitation path includes the first switch, the first auxiliary resonant inductor, the first main resonant inductor, the second main resonant inductor, the fourth switch, and the buck converter circuit. When the second switch and the third switch are simultaneously turned on, the second magnetic excitation path includes the second switch, the first main resonant inductor, the second main resonant inductor, the second auxiliary resonant inductor, the third switch, and the buck converter circuit.

[0020] In one embodiment, the output voltage of the power converter is adjusted by increasing the operating frequency of the primary-side isolation circuit to be greater than the resonant frequency.

[0021] In one embodiment, the output voltage of the power converter is adjusted by reducing the voltage of the preceding power factor correction circuit.

[0022] In one embodiment, when the conversion voltage is less than the first voltage, the fifth switch and the sixth switch turn on the buck converter circuit.

[0023] In one embodiment, when the conversion voltage is less than the second voltage, the fifth switch and the sixth switch turn on the buck converter circuit.

[0024] In one embodiment, a buck converter circuit is used to convert the conversion voltage into a DC output voltage.

[0025] In one embodiment, the switching voltage is reduced to a DC output voltage of different magnitudes by controlling the duty cycle of the fifth switch or the duty cycle of the sixth switch.

[0026] The proposed power converter can operate on half-bridge or full-bridge circuit topologies to flexibly provide multiple output voltages of different magnitudes.

[0027] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0028] Figure 1 This is a block diagram of the power converter architecture of the present invention.

[0029] Figure 2 This is a detailed block diagram of the power converter of the present invention.

[0030] Figure 3 , Figure 4 This is a circuit diagram of the DC-to-DC converter of the present invention.

[0031] In the attached figures, the following labels are used:

[0032] 1: Primary-side rectifier and filter circuit; 2: AC to DC converter.

[0033] 3: DC to DC converter; 4: Primary-side controller

[0034] 5: Secondary-side rectifier controller; 6: Secondary-side feedback controller

[0035] 7: Load

[0036] 31: Primary-side isolation circuit; 32: Secondary-side isolation circuit

[0037] 311: Bridge switching circuit; 312: Resonant circuit

[0038] 321: Bridge synchronous rectifier circuit; 322: Buck converter circuit

[0039] Q H Switch Q L : Down switch

[0040] Q1: First switch Q2: Second switch

[0041] Q3: Third switch Q4: Fourth switch

[0042] Q5: Fifth switch Q6: Sixth switch

[0043] W 11 First main resonant inductor W 12 Second main resonant inductor

[0044] W 21 First auxiliary resonant inductor W 22 Second auxiliary resonant inductor

[0045] C1: First capacitor; C2: Second capacitor

[0046] D: Diode L: Inductor

[0047] C: Capacitor

[0048] V IN Input voltage V INRF Adjust the input voltage

[0049] V INDC DC input voltage V CON : conversion voltage

[0050] V OUTDC DC output voltage

[0051] S C1 First control signal S C2 Second control signal

[0052] S C3 Third control signal S LP Load power demand signal

[0053] S CSR : Rectifier control signal S CAD AC / DC feedback control signal

[0054] S CDD DC / DC feedback control signal Detailed Implementation

[0055] The structural and working principles of the present invention will be described in detail below with reference to the accompanying drawings:

[0056] Please see Figure 1 , Figure 2 The figures shown are a block diagram and a detailed block diagram of the power converter of the present invention. The power converter with buck-boost conversion includes a primary-side rectifier and filter circuit 1, an AC-to-DC converter 2, a DC-to-DC converter 3, a primary-side controller 4, a secondary-side rectifier controller 5, and a secondary-side feedback controller 6.

[0057] Primary side rectifier and filter circuit 1 receives input voltage V IN And the rectified and filtered input voltage V IN Adjust the input voltage V by adjusting the output. INRF Specifically, the primary-side rectifier and filter circuit 1 includes a primary-side rectifier circuit and a primary-side filter circuit (not shown in the figure). The primary-side rectifier circuit is used to rectify the input voltage V. IN The voltage is rectified. The primary-side filter circuit is used to filter the rectified input voltage to adjust the output input voltage V. INRF To AC to DC converter 2.

[0058] The AC-to-DC converter 2 is coupled to the primary-side rectifier and filter circuit 1, and receives the adjusted input voltage V output by the primary-side rectifier and filter circuit 1. INRF .

[0059] DC-to-DC converter 3 is coupled to AC-to-DC converter 2. Specifically, as follows: Figure 3 , Figure 4 The diagram shown is a circuit diagram of the DC-to-DC converter of the present invention. The DC-to-DC converter 3 includes a primary-side isolation circuit 31 and a secondary-side isolation circuit 32. The primary-side isolation circuit 31 is coupled to the AC-to-DC converter 2 and the primary-side controller 4, and is used to receive the second control signal S provided by the primary-side controller 4. C2 With DC input voltage V INDC The secondary-side isolation circuit 32 is coupled to the secondary-side rectifier controller 5 to isolate the converted DC input voltage V. INDC .

[0060] The primary-side isolation circuit 31 includes a bridge switching circuit 311 and a resonant circuit 312. The bridge switching circuit 311 includes an upper switch Q. H With the lower switch Q L Switch Q H The first terminal is coupled to AC-to-DC converter 2. The lower switch Q... L The first terminal is coupled to switch Q H The second terminal is connected to the resonant circuit 312. The primary-side controller 4 provides the second control signal S. C2 Control switch Q H With the lower switch Q L .

[0061] The secondary-side isolation circuit 32 includes a bridge synchronous rectifier circuit 321 and a buck converter circuit 322. The bridge synchronous rectifier circuit 321 includes a first switch Q1, a second switch Q2, a third switch Q3, a fourth switch Q4, and a first main resonant inductor W. 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 Among them, the first main resonant inductor W 11 The second main resonant inductor W 12 With the first auxiliary resonant inductor W 21 Second auxiliary resonant inductor W 22 These are implemented by the main winding and auxiliary winding of the same inductive device (e.g., a transformer). Therefore, the first main resonant inductor W 11 The second main resonant inductor W 12 With the first auxiliary resonant inductor W 21 Second auxiliary resonant inductor W 22 The voltage on it is directly proportional to the ratio of the number of turns in the corresponding winding.

[0062] First auxiliary resonant inductor W 21 The first terminal is coupled to the second terminal of the first switch Q1, and the first auxiliary resonant inductor W 21 The second terminal is coupled to the first terminal of the second switch Q2 and the first main resonant inductor W. 11 The second terminal. The second auxiliary resonant inductor W. 22 The first terminal is coupled to the second terminal of the third switch Q3, and the second auxiliary resonant inductor W 22 The second terminal is coupled to the first terminal of the fourth switch Q4 and the second main resonant inductor W. 12 The first terminal. The first main resonant inductor W 11 The first end is coupled to the second main resonant inductor W 12 The second end. In this embodiment, the first main resonant inductor W 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 The first end of each is a dotted end, and the first main resonant inductor W 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 The second end is a non-dot end, but this is not a limitation of the present invention.

[0063] The first terminal of the third switch Q3 is coupled to the first terminal of the first switch Q1 and the buck converter circuit 322. The second terminal of the fourth switch Q4 is coupled to the second terminal of the second switch Q2 and the buck converter circuit 322. The secondary-side rectifier controller 5 provides the third control signal S. C3 Control the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4.

[0064] The bridge synchronous rectifier circuit 321 further includes a first capacitor C1 and a second capacitor C2. The first terminal of the first capacitor C1 is coupled to the first terminal of the third switch Q3 and the first terminal of the first switch Q1. The first terminal of the second capacitor C2 is coupled to the second terminal of the first capacitor C1 and the first main resonant inductor W. 11 The first terminal and the second main resonant inductor W 12 The second terminal (i.e., the first main resonant inductor W) 11 With the second main resonant inductor W 12 (The common terminal). The second terminal of the second capacitor C2 is coupled to the second terminal of the fourth switch Q4 and the second terminal of the second switch Q2.

[0065] The step-down converter circuit 322 is used to convert the switching voltage V. CON DC output voltage V OUTDC The step-down converter circuit 322 includes a fifth switch Q5, a sixth switch Q6, a diode D, an inductor L, and a capacitor C. The first terminal of the fifth switch Q5 is coupled to the first terminal of the third switch Q3 and the first terminal of the first capacitor C1. The first terminal of the sixth switch Q6 is coupled to the first main resonant inductor W. 11 The first terminal and the second main resonant inductor W 12 The second terminal of the fourth switch Q4 is coupled to the second terminal of the fifth switch Q5. The cathode of the diode D is coupled to the second terminal of the fifth switch Q5 and the second terminal of the sixth switch Q6. The first terminal of the inductor L is coupled to the cathode of the diode D. The first terminal of the capacitor C is coupled to the second terminal of the inductor L, and the second terminal of the capacitor C is coupled to the anode of the diode D and the second terminal of the fourth switch Q4. In one embodiment, the sixth switch Q6 can be implemented with back-to-back semiconductor elements, but this is not intended to limit the invention.

[0066] Primary-side controller 4 is coupled to AC-to-DC converter 2 and DC-to-DC converter 3, providing the first control signal S. C1 Control AC to DC converter 2 to adjust input voltage V INRF DC input voltage V INDC And provide a second control signal S C2 Control DC to DC converter 3.

[0067] The secondary-side rectifier controller 5 is coupled to the DC-to-DC converter 3, providing the third control signal S. C3Controlled DC-to-DC converter 3 converts DC input voltage V based on gain condition. INDC For the conversion voltage V CON Power is supplied to load 7.

[0068] The secondary-side feedback controller 6 is coupled to the primary-side controller 4 and the secondary-side rectifier controller 5. The secondary-side feedback controller 6 receives the load power demand signal S provided by the load 7. LP The operation of the primary-side controller 4 and the secondary-side rectifier controller 5 is controlled. Specifically, the secondary-side feedback controller 6 provides AC / DC feedback control signals S. CAD With DC feedback control signal S CDD The feedback control signal is sent to the primary-side controller 4, and a rectification control signal S is provided. CSR To the secondary side rectifier controller 5.

[0069] Primary-side controller 4 controls the AC / DC feedback control signal S. CAD Control the AC to DC converter 2 according to the DC / DC feedback control signal S CDD Control the DC-to-DC converter 3, and according to the rectification control signal S CSR Control the secondary side rectifier controller 5 and adjust the gain conditions.

[0070] When the bridge synchronous rectifier circuit 321 is in half-bridge operation, the conversion voltage V is as follows. CON The first voltage, for example but not limited to 20 volts, and the third control signal S C3 The first switch Q1 and the third switch Q3 are turned off, and the second switch Q2 and the fourth switch Q4 are switched on and off, thus exciting the first main resonant inductor W. 11 Or the second principal resonant inductor W 12 In this embodiment, when the second switch Q2 is turned on, the first magnetic excitation path is formed, including the second switch Q2 and the first main resonant inductor W. 11 And the step-down converter circuit 322, therefore the first main resonant inductor W 11 Excitation is performed. When the fourth switch Q4 is turned on, a second magnetic excitation path is formed, including the fourth switch Q4 and the second main resonant inductor W. 12 And the step-down converter circuit 322, therefore the second main resonant inductor W 12 Perform excitation.

[0071] The symmetrical circuit operation involves switching voltage V. CON When the voltage is the first value, the third control signal S C3 The second switch Q2 and the fourth switch Q4 are turned off, and the first switch Q1 and the third switch Q3 are switched on and off, thus exciting the first main resonant inductor W. 11 Or the second principal resonant inductor W 12In this embodiment, when the first switch Q1 is turned on, the third magnetic excitation path is formed, including the first switch Q1 and the first main resonant inductor W. 11 And the step-down converter circuit 322, therefore the first main resonant inductor W 11 Excitation is performed. When the third switch Q3 is turned on, a fourth magnetic excitation path is formed, including the third switch Q3 and the second main resonant inductor W. 12 And the step-down converter circuit 322, therefore the second main resonant inductor W 12 Perform excitation.

[0072] When the conversion voltage V CON When the voltage is less than the first voltage (i.e., less than 20 volts), the fifth switch Q5 and the sixth switch Q6 conduct the buck converter circuit 322. Specifically, by controlling the duty cycle of the fifth switch Q5 or the duty cycle of the sixth switch Q6, the switching voltage V is adjusted. CON Step-down to different DC output voltages V OUTDC This allows for the provision of multiple output voltages of different magnitudes.

[0073] However, in full-bridge operation requiring voltage multiplication output, only the first main resonant inductor W... 11 With the second main resonant inductor W 12 In the case of (i.e., without the first auxiliary resonant inductor W) 21 With the second auxiliary resonant inductor W 22 The output voltage and input voltage have a fixed multiple (e.g., 2 times). Therefore, to achieve a different multiple relationship between the output and input voltages, such as an input voltage of 20 volts and a desired output voltage of 48 volts, the input voltage of the pre-amplifier PFC (Power Factor Correction Circuit) needs to be increased (e.g., from 400 volts to 480 volts) to provide a 48-volt output voltage through a 2x voltage gain. However, the voltage boosted by the pre-amplifier PFC necessitates a larger bulk capacitor, which is detrimental to system miniaturization.

[0074] Therefore, the present invention further utilizes a first auxiliary resonant inductor W 21 With the second auxiliary resonant inductor W 22 Optimize circuit design. More specifically, by designing the first main resonant inductor W 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 The coil turns ratio is adjusted to achieve the purpose of this invention.

[0075] For example, however, this is not intended to limit the invention; the first primary resonant inductor W is designed. 11 The second main resonant inductor W12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 The coil turns ratio is 2:2:1:1. Therefore, under full-bridge operation (i.e., requiring voltage multiplication output), the first main resonant inductor W can be obtained. 11 The voltage (i.e., the voltage of the first main resonant inductor W) 11 The voltage across both ends (hereinafter the same) is 20 volts (referred to as the first voltage), and the second main resonant inductor W 12 The voltage is 20 volts (referred to as the second voltage), and the first auxiliary resonant inductor W 21 The voltage is 10 volts (referred to as the third voltage), and the second auxiliary resonant inductor W 22 The voltage is 10 volts (referred to as the fourth voltage). With the second switch Q2 and the third switch Q3 conducting in a full-bridge operation, the sum of the voltages across the first capacitor C1 and the second capacitor C2 is 50 volts (meaning the sum of the first voltage, the second voltage, and the fourth voltage). Similarly, with the first switch Q1 and the fourth switch Q4 conducting in a full-bridge operation, the sum of the voltages across the first capacitor C1 and the second capacitor C2 is 50 volts (meaning the sum of the first voltage, the second voltage, and the third voltage).

[0076] Under the aforementioned output voltage conditions, the 50-volt output voltage can be corrected to 48 volts in two ways. The first method involves increasing the operating frequency of the LLC circuit (i.e., the primary-side isolation circuit 31) above its resonant frequency. This slightly reduces the gain, achieving an output voltage of 48 volts. This eliminates the need to raise the voltage of the pre-amplifier PFC, thus avoiding the need for a larger capacitor. The second method, without increasing the LLC circuit's operating frequency, involves lowering the voltage of the pre-amplifier PFC (e.g., from 400 volts to 380 volts). This directly achieves an output voltage of 48 volts, meaning the first and second voltages are slightly less than 20 volts, and the third and fourth voltages are slightly less than 10 volts. The sum of these three voltages, or the sum of the first, second, and third voltages, directly reaches 48 volts. This not only reduces the size of the large capacitor, facilitating system miniaturization, but also improves power conversion efficiency.

[0077] Furthermore, the present invention can also utilize the first main resonant inductor W 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21 and the second auxiliary resonant inductor W 22 The design of different coil turns ratios allows the output voltage to meet the requirements of a wider range of voltages.

[0078] That is, when the bridge synchronous rectifier circuit 321 is in full-bridge operation, it is used to provide a voltage doubler output, at which time the conversion voltage V CON The second voltage, for example but not limited to 48 volts or 36 volts, and the third control signal S C3 Controlling the first switch Q1 and the fourth switch Q4 to simultaneously turn on and off, controlling the second switch Q2 and the third switch Q3 to simultaneously turn on and off, and controlling the first switch Q1 and the second switch Q2 to switch on and off alternately, excites the first main resonant inductor W. 11 With the second main resonant inductor W 12 and the first auxiliary resonant inductor W 21 Or the second auxiliary resonant inductor W 22 Specifically, when the first switch Q1 and the fourth switch Q4 are simultaneously turned on, the first magnetic excitation path includes the first switch Q1 and the first auxiliary resonant inductor W. 21 The first main resonant inductor W 11 The second main resonant inductor W 12 The fourth switch Q4 and the buck converter circuit 322, therefore, simultaneously affect the first main resonant inductor W. 11 The second main resonant inductor W 12 and the first auxiliary resonant inductor W 21 Excitation is performed. When the second switch Q2 and the third switch Q3 are simultaneously turned on, the second magnetic excitation path includes the second switch Q2 and the first main resonant inductor W. 11 The second main resonant inductor W 12 Second auxiliary resonant inductor W 22 The third switch Q3 and the buck converter circuit 322, therefore, simultaneously affect the first main resonant inductor W. 11 The second main resonant inductor W 12 and the second auxiliary resonant inductor W 22 Perform excitation.

[0079] When the conversion voltage V CON When the voltage is less than the second voltage (i.e., less than 48 volts or 36 volts), the fifth switch Q5 and the sixth switch Q6 conduct the buck converter circuit 322. By controlling the duty cycle of the fifth switch Q5 or the sixth switch Q6, the switching voltage V is adjusted. CON Step-down to different DC output voltages V OUTDC This allows for the provision of multiple output voltages of different magnitudes.

[0080] The power converter proposed in this invention can operate on half-bridge or full-bridge circuit topologies to flexibly provide multiple output voltages of different magnitudes. Furthermore, through the design of the first main resonant inductor W... 11 The second main resonant inductor W 12 First auxiliary resonant inductor W 21and the second auxiliary resonant inductor W 22 The coil turns ratio is adjusted to achieve an output voltage that meets the requirements of a wider voltage range.

[0081] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A power converter, characterized in that, Operating in half-bridge or full-bridge circuit topologies, it flexibly provides multiple output voltages of different magnitudes, including: A primary-side rectifier and filter circuit receives an input voltage, and rectifies and filters the input voltage to output an adjustable input voltage; An AC-to-DC converter is coupled to the primary-side rectifier and filter circuit and receives the adjusted input voltage; A DC-DC converter is continuously flowing, coupled to this AC-to-DC converter; A primary-side controller is coupled to the AC-to-DC converter and the DC-to-DC converter, providing a first control signal to control the AC-to-DC converter to convert the adjustable input voltage to a DC input voltage, and providing a second control signal to control the DC-to-DC converter; A secondary-side rectifier controller, coupled to the DC-to-DC converter, provides a third control signal to control the DC-to-DC converter to convert the DC input voltage into a converted voltage based on a gain condition, thereby supplying power to a load; and A secondary-side feedback controller is coupled to the primary-side controller and the secondary-side rectifier controller. The secondary-side feedback controller receives a load power demand signal provided by the load and controls the operation of the primary-side controller and the secondary-side rectifier controller.

2. The power converter as described in claim 1, characterized in that, The secondary-side feedback controller provides a feedback control signal, including an AC / DC feedback control signal and a DC feedback control signal, to the primary-side controller, and provides a rectification control signal to the secondary-side rectifier controller. The primary-side controller controls the AC-to-DC converter according to the AC / DC feedback control signal, controls the DC-to-DC converter according to the DC / DC feedback control signal, and controls the secondary-side rectifier controller and adjusts the gain condition according to the rectifier control signal.

3. The power converter as described in claim 1, characterized in that, The DC-to-DC converter includes: A primary-side isolation circuit, coupled to the AC-to-DC converter and the primary-side controller, is used to receive the second control signal and the DC input voltage; and A primary-side isolation circuit, coupled to the secondary-side rectifier controller, is used to isolate and convert the DC input voltage.

4. The power converter as described in claim 3, characterized in that, The primary-side isolation circuit includes a bridge switching circuit and a resonant circuit; the secondary-side isolation circuit includes a bridge synchronous rectification circuit and a buck converter circuit.

5. The power converter as described in claim 4, characterized in that, The bridge switching circuit includes: A switch is connected to the AC-to-DC converter, with one of its first terminals coupled to the switch. A switch is activated, with one of its first terminals coupled to a second terminal of the upper switch and the resonant circuit. The primary-side controller provides the second control signal to control the upper switch and the lower switch.

6. The power converter as described in claim 4, characterized in that, The bridge synchronous rectifier circuit includes: A first switch, a second switch, a third switch, and a fourth switch; A first main resonant inductor and a second main resonant inductor; and A first auxiliary resonant inductor and a second auxiliary resonant inductor; A first terminal of the first auxiliary resonant inductor is coupled to a second terminal of the first switch; a second terminal of the first auxiliary resonant inductor is coupled to a first terminal of the second switch and a second terminal of the first main resonant inductor; a first terminal of the second auxiliary resonant inductor is coupled to a second terminal of the third switch; a second terminal of the second auxiliary resonant inductor is coupled to a first terminal of the fourth switch and a first terminal of the second main resonant inductor; a first terminal of the first main resonant inductor is coupled to a second terminal of the second main resonant inductor. The first terminal of the third switch is coupled to the first terminal of the first switch and the buck converter circuit; the second terminal of the fourth switch is coupled to the second terminal of the second switch and the buck converter circuit. The secondary-side rectifier controller provides the third control signal to control the first switch, the second switch, the third switch, and the fourth switch.

7. The power converter as described in claim 6, characterized in that, The bridge synchronous rectifier circuit further includes: A first capacitor, wherein a first terminal of the first capacitor is coupled to the third switch; and A second capacitor, a first terminal of which is coupled to a second terminal of the first capacitor, and a second terminal of the second capacitor is coupled to the fourth switch.

8. The power converter as described in claim 6, characterized in that, The buck converter circuit includes: A fifth switch, wherein a first terminal of the fifth switch is coupled to the first terminal of the third switch; A sixth switch, wherein a first terminal of the sixth switch is coupled to the first terminal of the first main resonant inductor and the second terminal of the second main resonant inductor, and a second terminal of the sixth switch is coupled to a second terminal of the fifth switch; A diode, wherein a cathode of the diode is coupled to the second terminal of the fifth switch and the second terminal of the sixth switch; An inductor, a first terminal of which is coupled to the cathode of the diode; and A capacitor, a first terminal of which is coupled to a second terminal of an inductor, and a second terminal of which is coupled to an anode of a diode and a second terminal of a fourth switch.

9. The power converter as described in claim 8, characterized in that, When the conversion voltage is a first voltage, the first switch and the third switch are turned off, and the second switch and the fourth switch switch to conduct, thereby energizing the first main resonant inductor or the second main resonant inductor.

10. The power converter as claimed in claim 9, characterized in that, When the second switch is turned on, a first magnetic excitation path is formed, including the second switch, the first main resonant inductor, and the buck converter circuit, to excite the first main resonant inductor; when the fourth switch is turned on, a second magnetic excitation path is formed, including the fourth switch, the second main resonant inductor, and the buck converter circuit, to excite the second main resonant inductor.

11. The power converter as claimed in claim 6, characterized in that, When the conversion voltage is a first voltage, the second switch and the fourth switch are turned off, and the first switch and the third switch switch to conduct, thereby energizing the first main resonant inductor or the second main resonant inductor.

12. The power converter as claimed in claim 11, characterized in that, When the first switch is turned on, a third magnetic excitation path is formed, including the first switch, the first main resonant inductor, and the buck converter circuit, to excite the first main resonant inductor; when the third switch is turned on, a fourth magnetic excitation path is formed, including the third switch, the second main resonant inductor, and the buck converter circuit, to excite the second main resonant inductor.

13. The power converter as claimed in claim 8, characterized in that, When the conversion voltage is a second voltage, the first switch and the fourth switch are simultaneously turned on and off, the second switch and the third switch are simultaneously turned on and off, and the first switch and the second switch switch on and off to excite the first main resonant inductor, the second main resonant inductor, and the first auxiliary resonant inductor or the second auxiliary resonant inductor.

14. The power converter as claimed in claim 12, characterized in that, When the first switch and the fourth switch are simultaneously turned on, a first magnetic excitation path is formed, including the first switch, the first auxiliary resonant inductor, the first main resonant inductor, the second main resonant inductor, the fourth switch, and the buck converter circuit; when the second switch and the third switch are simultaneously turned on, a second magnetic excitation path is formed, including the second switch, the first main resonant inductor, the second main resonant inductor, the second auxiliary resonant inductor, the third switch, and the buck converter circuit.

15. The power converter as claimed in claim 6, characterized in that, This involves adjusting the output voltage of the power converter by increasing the operating frequency of the primary-side isolation circuit to be greater than the resonant frequency.

16. The power converter as claimed in claim 6, characterized in that, This involves lowering the voltage of a pre-amplifier power factor correction circuit to adjust the output voltage of the power converter.

17. The power converter as claimed in claim 9, characterized in that, When the conversion voltage is less than the first voltage, the fifth switch and the sixth switch turn on the buck converter circuit.

18. The power converter as claimed in claim 13, characterized in that, When the conversion voltage is less than the second voltage, the fifth switch and the sixth switch turn on the buck converter circuit.

19. The power converter as claimed in claim 8, characterized in that, The step-down converter circuit is used to convert the converted voltage into a DC output voltage.

20. The power converter as claimed in claim 19, characterized in that, By controlling one duty cycle of the fifth switch or one duty cycle of the sixth switch, the switching voltage is reduced to the DC output voltage of different magnitudes.

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