A large-ratio inductance transformer hybrid converter

Abstract

The application belongs to the technical field of power electronics, and relates to a large-ratio inductance transformer hybrid converter, which comprises a four-stage special phase power supply unit PS, an energy storage capacitor is arranged to realize equal distribution of input voltage among stages of each power supply unit, and voltage stress of each switch tube is reduced; the four-stage special phase power supply unit PS is electrically connected with four-stage normal phase power supply units P1-P6 and four-stage final phase power supply units PF respectively, the four-stage special phase power supply unit PS, the four-stage normal phase power supply units P1-P6 and the four-stage final phase power supply units PF are all electrically connected with an input end Vin of the converter respectively, and the four-stage final phase power supply units PF are electrically connected with an output end Vout of the converter; therefore, on the basis of realizing high conversion ratio of 48V-0.75V, the application expands the duty cycle of a driving waveform, reduces inductance current ripple, and meets the requirement of high conversion ratio.

Description

Technical Field

[0001] This invention belongs to the field of power electronics technology and relates to a hybrid converter with a large turns ratio inductor transformer. Background Technology

[0002] Data centers, as core facilities for processing and storing massive amounts of data, bear the crucial function of providing a large number of cloud computing services. With the ever-increasing business demands, the number and scale of servers have expanded dramatically, placing higher demands on the power supply of data centers and posing significant challenges. Compared to 12V buses, 48V buses not only significantly reduce conduction losses on the bus but also greatly improve the AC-DC conversion efficiency of the upstream stage, simplifying the power conversion of the entire power supply chain and resulting in higher energy efficiency. 48V buses present three major technical challenges to the design of downstream voltage regulator modules (VRMs): high step-down ratio, low-voltage high-current operation, and ultra-fast dynamic response.

[0003] However, traditional multiphase buck converters are used to complete the conversion from 12V to approximately 0.75V, but the overall losses are relatively large, and there is a problem of uneven current distribution between the phases of the multiphase buck converter.

[0004] Therefore, a converter is needed that can perform direct voltage conversion from 48V to 0.75V, achieve high current output of over 1000A, and also possess excellent performance characteristics such as high power density, high efficiency, and low device stress to solve the above technical problems. Summary of the Invention

[0005] The technical solution adopted by this invention to solve the technical problem is: a hybrid converter with a large transformation ratio inductor-transformer, comprising:

[0006] A four-stage special phase power supply unit (PS) uses energy storage capacitors to distribute the input voltage evenly among the various stages of the power supply unit, thereby reducing the voltage stress on each switching transistor.

[0007] Six four-stage ordinary phase power supply units P1 to P6 and one four-stage final phase power supply unit PF are used to reduce the equivalent inductance of each power supply unit during the dynamic load change process. Through magnetic flux cancellation, the transformer volume of the ordinary phase power supply unit is reduced.

[0008] The four-level special phase power supply unit PS, the four-level ordinary phase power supply units P1 to P6, and the four-level last phase power supply unit PF are each equipped with three energy storage capacitors. The energy storage capacitors are used to balance the current between each stage of each power supply unit so that the steady-state average voltage is constant.

[0009] The four-level special phase power supply unit PS is electrically connected to the four-level ordinary phase power supply units P1 to P6 and the four-level last phase power supply unit PF, respectively. The four-level special phase power supply unit PS, the four-level ordinary phase power supply units P1 to P6, and the four-level last phase power supply unit PF are all electrically connected to the input terminal Vin of the converter, and the four-level last phase power supply unit PF is electrically connected to the output terminal Vout of the converter.

[0010] Preferably, the four-stage special phase power supply unit PS includes: switching transistors S11, S21, S31, S41, S12, S22, S32, and S42; energy storage capacitors Ct11, Ct21, and Ct31; and special phase inductors L1, L2, L3, and L4. The circuit connection of the four-stage special phase power supply unit PS is as follows: one end of switching transistor S11 is connected to the input terminal Vin of the converter; the other end of switching transistor S11 is connected to one end of switching transistor S21 and one end of energy storage capacitor Ct11; the other end of energy storage capacitor Ct11 is connected to one end of switching transistor S12 and one end of special phase inductor L1; and the other end of switching transistor S12 is grounded. The other end of switch S21 is connected to one end of switch S31 and one end of energy storage capacitor Ct21. The other end of energy storage capacitor Ct21 is connected to one end of switch S22 and one end of special phase inductor L2. The other end of switch S22 is grounded. The other end of switch S31 is connected to one end of switch S41 and one end of energy storage capacitor Ct31. The other end of energy storage capacitor Ct31 is connected to one end of switch S32 and one end of special phase inductor L3. The other end of switch S32 is grounded. The other end of switch S41 is connected to one end of low-side switch S42 and one end of special phase inductor L4. The other end of switch S42 is grounded.

[0011] More preferably, the four-level ordinary phase power supply units P1 to P6 each include: switching transistors S1x, S2x, S3x, S4x, switching transistors S1y, S2y, S3y, S4y, energy storage capacitors Ct1z, Ct2z, Ct3z, and ordinary phase transformers Tr1w, Tr2w, Tr3w, Tr4w, where x is 3, 5, 7, 9, 11, 13, z is 2, 3, 4, 5, 6, 7 respectively, y = x + 1, w = z - 1;

[0012] The circuit connection of the four-stage ordinary phase power supply units P1 to P6 is as follows: one end of the switch S1x is connected to the input terminal Vin of the converter; the other end of the switch S1x is simultaneously connected to one end of the switch S2x and one end of the energy storage capacitor Ct1z; the other end of the energy storage capacitor Ct1z is connected to one end of the switch S1y and one end of the primary side of the ordinary phase transformer Tr1w; the other end of the switch S1y is grounded; and the other end of the primary side of the ordinary phase transformer Tr1w is connected to the output terminal Vout. The other end of the switch S2x is connected to one end of the switch S3x and one end of the energy storage capacitor Ct2z; the other end of the energy storage capacitor Ct2z is connected to one end of the switch S2y and the primary side of the ordinary phase transformer Tr2w. One end of the switching transistor S22 is grounded, and the other end of the primary side of the ordinary phase transformer Tr2w is connected to the output terminal Vout; the other end of the switching transistor S3x is connected to one end of the switching transistor S4x and one end of the energy storage capacitor Ct3z, and the other end of the energy storage capacitor Ct3z is connected to one end of the switching transistor S3y and one end of the primary side of the ordinary phase transformer Tr3w; the other end of the switching transistor S32 is grounded, and the other end of the primary side of the ordinary phase transformer Tr3w is connected to the output terminal Vout; the other end of the switching transistor S4x is connected to one end of the switching transistor S4y and one end of the primary side of the ordinary phase transformer Tr4w, and the other end of the switching transistor S4y is grounded, and the other end of the primary side of the ordinary phase transformer Tr4w is connected to the output terminal Vout.

[0013] The end of the special phase inductor Ln that is not connected to the switching transistor is connected to one end of the secondary side of the ordinary phase transformer Trn1, where n = 1, 2, 3, 4; the other end of the secondary side of the ordinary phase transformer Trn1 is connected in series with the secondary sides of ordinary phase transformer Trn2, ordinary phase transformer Trn3, ordinary phase transformer Trn4, and ordinary phase transformer Trn5, and then connected to one end of the secondary side of ordinary phase transformer Trn6.

[0014] More preferably, the four-stage final phase power supply unit PF includes: switching transistors S115, S215, S315, S415, switching transistors S116, S216, S316, S416, energy storage capacitors Ct18, Ct28, Ct38, and ordinary phase transformers Tr17, Tr27, Tr37, Tr47.

[0015] The circuit connection of the fourth-stage final-phase power supply unit PF is as follows: one end of the switching transistor S115 is connected to the input terminal Vin of the converter; the other end of the switching transistor S115 is connected to one end of the switching transistor S215 and one end of the energy storage capacitor Ct18; the other end of the energy storage capacitor Ct18 is connected to one end of the switching transistor S116 and one end of the primary winding of the ordinary phase transformer Tr17; the other end of the switching transistor S116 is grounded; and the other end of the primary winding of the ordinary phase transformer Tr17 is connected to the output terminal Vout. The other end of the switching transistor S215 is connected to one end of the switching transistor S315 and one end of the energy storage capacitor Ct28; the other end of the energy storage capacitor Ct28 is connected to one end of the switching transistor S216 and one end of the primary winding of the ordinary phase transformer Tr27. The other end of switch S22 is grounded, and the other end of the primary side of ordinary phase transformer Tr27 is connected to the output terminal Vout; the other end of switch S315 is connected to one end of switch S415 and one end of energy storage capacitor Ct38, and the other end of energy storage capacitor Ct38 is connected to one end of switch S316 and one end of the primary side of ordinary phase transformer Tr37; the other end of switch S32 is grounded, and the other end of the primary side of ordinary phase transformer Tr37 is connected to the output terminal Vout; the other end of switch S415 is connected to one end of switch S416 and one end of the primary side of ordinary phase transformer Tr47, and the other end of switch S416 is grounded, and the other end of the primary side of ordinary phase transformer Tr47 is connected to the output terminal Vout;

[0016] The other end of the secondary side of the ordinary phase transformer Trn6 is connected to one end of the ordinary phase transformer Trn7, and the other end of the ordinary phase transformer Trn7 is connected to the output terminal Vout.

[0017] More preferably, the driving waveforms of the switches S11, S31, S29, and S49 are the same, and the driving waveforms of the switches S12, S32, S210, and S410 are the same; the driving waveforms of the switches S11 and S12 are complementary; and the duty cycle D of the switches during operation is related to the gain of the converter.

[0018] The driving waveforms of switches S13, S33, S211, and S411 are the same, as are the driving waveforms of switches S14, S34, S212, and S412; the driving waveforms of switches S13 and S14 are complementary; the driving waveform of switch S13 lags behind the driving waveform of switch S11 by 45°.

[0019] The driving waveforms of switches S15, S35, S213, and S413 are the same, as are the driving waveforms of switches S16, S36, S214, and S414; the driving waveforms of switches S15 and S16 are complementary; the driving waveform of switch S15 lags behind the driving waveform of switch S11 by 90°.

[0020] The driving waveforms of switches S17, S37, S215, and S415 are the same, as are the driving waveforms of switches S18, S38, S216, and S416; the driving waveforms of switches S17 and S18 are complementary; the driving waveform of switch S17 lags behind the driving waveform of switch S11 by 135°.

[0021] The driving waveforms of switching transistors S19, S39, S21, and S41 are the same, as are the driving waveforms of switching transistors S110, S310, S22, and S42. The driving waveforms of switching transistors S19 and S110 are complementary, and the driving waveform of switching transistor S19 lags behind the driving waveform of switching transistor S11 by 180°.

[0022] The driving waveforms of switches S111, S311, S23, and S43 are the same, and the driving waveforms of switches S112, S312, S24, and S44 are the same. The driving waveforms of switches S111 and S112 are complementary, and the driving waveform of switch S111 lags behind the driving waveform of switch S112 by 225°.

[0023] The driving waveforms of switches S113, S313, S25, and S45 are the same, as are the driving waveforms of switches S114, S314, S26, and S46. The driving waveforms of switches S113 and S114 are complementary, with the driving waveform of switch S113 lagging behind that of switch S11 by 270°.

[0024] The driving waveforms of switches S115, S315, S27, and S47 are the same, as are the driving waveforms of switches S116, S316, S28, and S48. The driving waveforms of switches S115 and S116 are complementary, and the driving waveform of switch S115 lags behind the driving waveform of switch S11 by 315°.

[0025] Preferably, the switching transistors in the converter are all gallium nitride switching transistors.

[0026] Preferably, the driving waveform of the switching transistor in the converter is provided with a dead time.

[0027] Preferably, the duty cycle D of the drive waveform when the switching transistor in the converter is working is less than 0.125.

[0028] Preferably, the gain of the converter is determined by the duty cycle of the driving waveform, and the calculation formula is:

[0029]

[0030] In equation (1), V in Indicates the input voltage, V out The output voltage is represented by , and D represents the duty cycle of the drive waveform.

[0031] Preferably, the total ripple value of the inductor current of the converter is jointly determined by the duty cycle, switching cycle, inductance value of the special phase, magnetizing inductance value of the ordinary phase transformer, input voltage, and output voltage, and the calculation formula is:

[0032]

[0033] In equation (2), V in Indicates the input voltage, V out Indicates the output voltage, D represents the duty cycle of the drive waveform, T represents the switching period, and L represents the inductance value of the special phase. m ΔI represents the magnetizing inductance value of a typical phase transformer. Lsum This represents the total ripple value of the inductor current.

[0034] Preferably, the converter is composed of a hybrid magnetic coupling structure of inductor-transformer consisting of special phase inductors L1-L4 and ordinary phase transformers Tr1w, Tr2w, Tr3w, and Tr4w (where w are positive integers from 1 to 7).

[0035] Preferably, the converter topology has an automatic current balancing mechanism, eliminating the need for an additional inductor current balancing circuit, thereby simplifying controller design.

[0036] The beneficial effects of this invention are:

[0037] 1. Based on achieving a high conversion ratio of 48V-0.75V, this invention expands the duty cycle of the drive waveform and reduces the inductor current ripple, thus meeting the requirements for high conversion ratio.

[0038] 2. This invention reduces the core volume of ordinary phase transformers, thus meeting the requirements for high power density.

[0039] 3. This invention eliminates the need for an intermediate bus capacitor, thus meeting power density requirements.

[0040] 4. This invention reduces the current ripple of the special phase inductor, reduces losses, and meets the requirements of high efficiency.

[0041] 5. This invention can achieve a high current output of 1200A, meeting the needs of high current power supply.

[0042] 6. The automatic current balancing mechanism of this invention eliminates the need for an additional inductor current balancing circuit in the converter, thereby simplifying the controller design. Attached Figure Description

[0043] Figure 1 This is a circuit diagram of a high-ratio inductor-transformer hybrid converter according to the present invention;

[0044] Figure 2 This is the circuit timing diagram of the present invention;

[0045] Figure 3 This is the equivalent circuit diagram of the working mode of the present invention;

[0046] Figure 4 This is the equivalent circuit diagram of the two working modes of the present invention;

[0047] Figure 5 This is the equivalent circuit diagram of the three-circuit operating modes of the present invention;

[0048] Figure 6 This is the equivalent circuit diagram of the four-circuit operating mode of the present invention;

[0049] Figure 7 This is a simulation waveform diagram of the inductor current of each phase during dynamic load shedding according to the present invention;

[0050] Figure 8 This is a simulation waveform diagram of the output voltage and current during dynamic load shedding of the present invention;

[0051] Figure 9 This is a simulation waveform of the inductor current of each phase during dynamic loading of the present invention;

[0052] Figure 10 This is a simulation waveform of the output voltage and current during dynamic loading of the present invention. Detailed Implementation

[0053] The related technologies of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0054] refer to Figures 1-10In this embodiment, a high-ratio inductor-transformer hybrid converter includes: one four-stage special phase power supply unit PS, six four-stage ordinary phase power supply units P1-P6, one four-stage last phase power supply unit PN, and an input terminal Vin, an output terminal Vout, and a ground terminal; the four-stage special phase power supply unit PS includes four high-side switches S11, S21, S31, and S41, four low-side switches S12, S22, S32, and S42, energy storage capacitors Ct11, Ct21, and Ct31, and special phase inductors L1, L2, L3, and L4; one end of the high-side switch S11 is connected to the input terminal Vin, and the other end of the high-side switch S11 is simultaneously connected to one end of the high-side switch S21 and one end of the energy storage capacitor Ct11; the other end of the energy storage capacitor Ct11 is simultaneously connected to one end of the low-side switch S12, ... One end of the special phase inductor L1; the other end of the low-side switch S12 is grounded; the other end of the high-side switch S21 is simultaneously connected to one end of the high-side switch S31 and one end of the energy storage capacitor Ct21, and the other end of the energy storage capacitor Ct21 is simultaneously connected to one end of the low-side switch S22 and one end of the special phase inductor L2; the other end of the low-side switch S22 is grounded; the other end of the high-side switch S31 is simultaneously connected to one end of the high-side switch S41 and one end of the energy storage capacitor Ct31, and the other end of the energy storage capacitor Ct31 is simultaneously connected to one end of the low-side switch S32 and one end of the special phase inductor L3; the other end of the low-side switch S32 is grounded; the other end of the high-side switch S41 is simultaneously connected to one end of the low-side switch S42 and one end of the special phase inductor L4; the other end of the low-side switch S42 is grounded.Each of the four-stage ordinary phase power supply units P1-P6 includes four high-side switching transistors S1x, S2x, S3x, and S4x; four low-side switching transistors S1y, S2y, S3y, and S4y; energy storage capacitors Ct1z, Ct2z, and Ct3z; and ordinary phase transformers Tr1w, Tr2w, Tr3w, and Tr4w (where x is 3, 5, 7, 9, 11, and 13, z is 2, 3, 4, 5, 6, and 7 respectively, y = x + 1, and w = z - 1); high-side switching transistors... One end of transistor S1x is connected to the input terminal Vin. The other end of high-side switch S1x is simultaneously connected to one end of high-side switch S2x and one end of energy storage capacitor Ct1z. The other end of energy storage capacitor Ct1z is simultaneously connected to one end of low-side switch S1y and one end of the primary winding of ordinary phase transformer Tr1w. The other end of low-side switch S1y is grounded. The other end of the primary winding of ordinary phase transformer Tr1w is connected to the output terminal Vout. The other end of high-side switch S2x is simultaneously connected to the high-side... One end of the switching transistor S3x and one end of the energy storage capacitor Ct2z are connected. The other end of the energy storage capacitor Ct2z is simultaneously connected to one end of the low-side switching transistor S2y and one end of the primary side of the ordinary phase transformer Tr2w. The other end of the low-side switching transistor S22 is grounded. The other end of the primary side of the ordinary phase transformer Tr2w is connected to the output terminal Vout. The other end of the high-side switching transistor S3x is simultaneously connected to one end of the high-side switching transistor S4x and one end of the energy storage capacitor Ct3z. The other end of the energy storage capacitor Ct3z is simultaneously connected to one end of the low-side switching transistor S3y and one end of the primary side of the ordinary phase transformer Tr3w. The other end of the low-side switching transistor S32 is grounded. The other end of the primary side of the ordinary phase transformer Tr3w is connected to the output terminal Vout. The other end of the high-side switching transistor S4x is simultaneously connected to one end of the low-side switching transistor S4y and one end of the primary side of the ordinary phase transformer Tr4w. The other end of the low-side switching transistor S4y is grounded. The other end of the primary side of the ordinary phase transformer Tr4w is connected to the output terminal Vout.The four-stage final-phase power supply unit PN includes four high-side switches S115, S215, S315, and S415; four low-side switches S116, S216, S316, and S416; energy storage capacitors Ct18, Ct28, and Ct38; and ordinary phase transformers Tr17, Tr27, Tr37, and Tr47. One end of the high-side switch S115 is connected to the input terminal Vin, and the other end of the high-side switch S115 is simultaneously connected to one end of the high-side switch S215 and one end of the energy storage capacitor Ct18. The other end of the energy storage capacitor Ct18 is simultaneously connected to one end of the low-side switch S116 and one end of the primary side of the ordinary phase transformer Tr17. The other end of the low-side switch S116 is the ground terminal. The other end of the primary side of the ordinary phase transformer Tr17 is connected to the output terminal Vout. The other end of the high-side switch S215 is simultaneously connected to one end of the high-side switch S315 and one end of the energy storage capacitor Ct28. The other end of the energy storage capacitor Ct28 is simultaneously connected to one end of the low-side switch S216 and one end of the primary side of the ordinary phase transformer Tr27; the other end of the low-side switch S22 is the ground terminal; the other end of the primary side of the ordinary phase transformer Tr27 is connected to the output terminal Vout; the other end of the high-side switch S315 is simultaneously connected to one end of the high-side switch S415 and one end of the energy storage capacitor Ct38; the other end of the energy storage capacitor Ct38 is simultaneously connected to one end of the low-side switch S316 and one end of the primary side of the ordinary phase transformer Tr37; the other end of the low-side switch S32 is the ground terminal; the other end of the primary side of the ordinary phase transformer Tr37 is connected to the output terminal Vout; the other end of the high-side switch S415 is simultaneously connected to one end of the low-side switch S416 and one end of the primary side of the ordinary phase transformer Tr47; the other end of the low-side switch S416 is the ground terminal; the other end of the primary side of the ordinary phase transformer Tr47 is connected to the output terminal Vout. The four special phase inductors Ln (n = 1, 2, 3, 4) are connected at one end not to the low-side switching transistor to one end of the secondary side of ordinary phase transformer Trn1. The other end of the secondary side of ordinary phase transformer Trn1 is connected to one end of the secondary side of ordinary phase transformer Trn2. The other end of the secondary side of ordinary phase transformer Trn2 is connected to one end of the secondary side of ordinary phase transformer Trn3. The other end of the secondary side of ordinary phase transformer Trn3 is connected to one end of the secondary side of ordinary phase transformer Trn4. The other end of the secondary side of ordinary phase transformer Trn4 is connected to one end of the secondary side of ordinary phase transformer Trn5. The other end of the secondary side of ordinary phase transformer Trn5 is connected to one end of the secondary side of ordinary phase transformer Trn6. The other end of the secondary side of ordinary phase transformer Trn6 is connected to one end of the secondary side of ordinary phase transformer Trn7. The other end of the secondary side of ordinary phase transformer Trn7 is connected to the output terminal Vout. The primary and secondary sides of the above ordinary phase transformers need to be connected in a reverse coupling relationship.

[0055] Figure 2 for Figure 1The circuit timing diagram of the high-ratio inductor-transformer hybrid converter is shown, including the drive waveforms G1 and G2 of the switching transistors and the current I on the special phase inductor L1. L1 The primary current I of a common phase transformer Tr11 Tr11 The primary current waveforms of ordinary phase transformers Tr12, Tr13, Tr14, Tr15, Tr16, and Tr17 lag behind I in sequence. Tr11 The angles are: 45°, 90°, 135°, 180°, 225°, 270°, 315°; the current waveforms on the special phase inductors L2, L3, and L4 are similar to I. L1The primary current waveforms of ordinary phase transformers Tr21, Tr22, Tr23, Tr25, Tr26, and Tr27 are identical to those of ordinary phase transformers Tr15, Tr16, Tr17, Tr11, Tr12, and Tr13, respectively. The primary current waveform of ordinary phase transformer Tr24 lags behind that of ordinary phase transformer Tr14 by 180°. The waveforms of ordinary phase transformers Tr1a and Tr3a are identical, and the waveforms of ordinary phase transformers Tr2a and Tr4a are identical (where a is a positive integer from 1 to 7). The control terminals of the switching transistors are used to input drive signals. When drive signal G1 is high, switches S11, S31, S29, and S49 are turned on; when drive signal G1 is low, switches S11, S31, S29, and S49 are turned off. When drive signal G2 is high, switches S13 and S49 are turned off. 33. Switches S211 and S411 are turned on; when drive signal G2 is low, switches S13, S33, S211, and S411 are turned off; Other drive signals not shown in the diagram include drive signals G3, G4, G5, G6, G7, and G8, which lag behind drive signal G2 by angles of 45°, 90°, 135°, 180°, 225°, and 270° respectively; when drive signal G3 is high, switches S15, S35, S213, and S413 are turned on; when drive signal G3 is low, switches S15, S33, S211, and S411 are turned off. 35. Switches S213 and S413 are off; when drive signal G4 is high, switches S17, S37, S215, and S415 are on; when drive signal G4 is low, switches S17, S37, S215, and S415 are off; when drive signal G5 is high, switches S19, S39, S21, and S41 are on; when drive signal G5 is low, switches S19, S39, S21, and S41 are off; when drive signal G6 is high, switches S111, S311, and S23... When switch S43 is turned on, switches S111, S311, S23, and S43 are turned off when drive signal G6 is low; when drive signal G7 is high, switches S113, S313, S25, and S45 are turned on, and when drive signal G7 is low, switches S113, S313, S25, and S45 are turned off; when drive signal G8 is high, switches S115, S315, S27, and S47 are turned on, and when drive signal G8 is low, switches S115, S315, S27, and S47 are turned off.Switches S12, S32, S210, and S410 operate in complementarity with switches S11, S31, S29, and S49, respectively; switches S14, S34, S212, and S412 operate in complementarity with switches S13, S33, S211, and S411, respectively; switches S16, S36, S214, and S414 operate in complementarity with switches S15, S35, S213, and S413, respectively; switches S18, S38, S216, and S416 operate in complementarity with switches S17, S37, S215, and S415, respectively. Switches S110, S310, S22, and S42 operate complementaryly to switches S19, S39, S21, and S41, respectively; switches S112, S312, S24, and S44 operate complementaryly to switches S111, S311, S23, and S43, respectively; switches S114, S314, S26, and S46 operate complementaryly to switches S113, S313, S25, and S45, respectively; and switches S116, S316, S28, and S48 operate complementaryly to switches S115, S315, S27, and S47, respectively. Dead time is incorporated into the complementary operation of the switches to prevent common circuitry.

[0056] Figure 3 for Figure 1 The equivalent circuit diagram when drive signal G1 is high and drive signals G2-G8 are all low. Input terminal Vin charges energy storage capacitor Ct11 and special phase inductor L1. The voltage across energy storage capacitor Ct11 stabilizes at 3Vin / 4. Ordinary phase transformers Tr11-Tr17 discharge to the output terminal. Energy storage capacitors Ct25 and Ct15 are connected in series, with an equivalent voltage Vin / 4, charging the primary side of ordinary phase transformer Tr24. Ordinary phase transformers Tr21, Tr22, Tr23, Tr25, Tr26, and Tr27 discharge to the output terminal. Energy storage capacitor Ct... 21 and energy storage capacitor Ct31 are connected in series, with an equivalent voltage Vin / 4, to charge the special phase inductor L3, and ordinary phase transformers Tr31-Tr37 discharge to the output terminal; energy storage capacitor Ct35, with an equivalent voltage Vin / 4, charges the primary side of ordinary phase transformer Tr44, and ordinary phase transformers Tr41, Tr42, Tr43, Tr45, Tr46, and Tr47 discharge to the output terminal; the output terminal Vout voltage is 0.75V, realizing the 48V-0.75V voltage conversion. Ignoring the influence of dead time, under steady-state conditions, equation (3) can be derived:

[0057]

[0058] Among them, V in V is the input voltage. o L is the output voltage, and L is the value of the special phase inductance. m This is the magnetizing inductance value of a typical phase transformer.

[0059] The results were:

[0060]

[0061] Where T is the switching period.

[0062] For the total ripple value ΔI of the inductor current Lsum As shown in equation (5):

[0063]

[0064] Figure 4 for Figure 1 The equivalent circuit diagram when all drive signals G1-G8 are low. Special phase inductors L1-L4, ordinary phase transformers Tr11-Tr17, Tr21-Tr27, Tr31-Tr37, and Tr41-Tr47 all discharge to the output terminal; the output terminal Vout voltage is 0.75V, realizing the 48V-0.75V voltage conversion. Ignoring the influence of dead time, under steady-state conditions, equation (6) can be derived:

[0065]

[0066] Where j = 1, 2, 3, 4, n = 1, 2, 3, 4, 5, 6, 7.

[0067] The results were:

[0068]

[0069] Among them, V in V is the input voltage. o L is the output voltage, and L is the value of the special phase inductance. m T represents the magnetizing inductance value of a typical phase transformer. off The duration during which G1-G8 are all at a low level.

[0070] Figure 5 for Figure 1The equivalent circuit diagram when drive signal G2 is high and drive signals G1, G3-G8 are all low. Input terminal Vin charges the primary side of energy storage capacitor Ct12 and ordinary phase transformer Tr11. The voltage across energy storage capacitor Ct12 stabilizes at 3Vin / 4. Ordinary phase transformers Tr12-Tr17 discharge to the output terminal. Energy storage capacitors Ct26 and Ct16 are connected in series, with an equivalent voltage Vin / 4, charging the primary side of ordinary phase transformer Tr25. Ordinary phase transformers Tr21, Tr22, Tr23, Tr24, Tr26, and Tr27 discharge to the output terminal. Energy storage capacitor C... t22 and energy storage capacitor Ct32 are connected in series, with an equivalent voltage Vin / 4, which charges the ordinary phase transformer Tr31. Ordinary phase transformers Tr32-Tr37 discharge to the output terminal. Energy storage capacitor Ct36, with an equivalent voltage Vin / 4, charges the primary side of ordinary phase transformer Tr45. Ordinary phase transformers Tr41, Tr42, Tr43, Tr44, Tr46, and Tr47 discharge to the output terminal. The output terminal Vout voltage is 0.75V, realizing the 48V-0.75V voltage conversion. Ignoring the influence of dead time, under steady-state conditions, equation (8) can be derived:

[0071]

[0072] By rearranging the formula, we obtain the current ripple values ​​for each special phase inductor and the ordinary phase transformer:

[0073]

[0074] For the total ripple value ΔI of the inductor current Lsum As shown in equation (10):

[0075]

[0076] According to the formula for total inductor current ripple, it can be found that the total inductor current ripple of mode three is greater than that of mode one.

[0077] akin, Figure 1 In the following six operating modes, the operating characteristics are similar to those of mode three, and the relationship of the total inductor current ripple is consistent with that of mode three:

[0078] (1) When drive signal G2 is high and drive signals G1, G3-G8 are all low;

[0079] (2) When drive signal G3 is high and drive signals G1, G2, and G4-G8 are all low;

[0080] (3) When drive signal G4 is high and drive signals G1-G3 and G5-G8 are all low;

[0081] (4) When drive signal G6 is high and drive signals G1-G5, G7 and G8 are all low;

[0082] (5) When drive signal G7 is high and drive signals G1-G6 and G8 are all low;

[0083] (6) When drive signal G8 is high and drive signals G1-G7 are all low;

[0084] Figure 6 for Figure 1 The equivalent circuit diagram when drive signal G5 is high and drive signals G1-G4 and G6-G8 are all low. Input terminal Vin charges the primary side of energy storage capacitor Ct15 and ordinary phase transformer Tr14. The voltage across energy storage capacitor Ct15 stabilizes at 3Vin / 4. Ordinary phase transformers Tr11, Tr12, Tr13, Tr15, Tr16, and Tr17 discharge to the output terminal. Energy storage capacitor Ct21 is connected in series with energy storage capacitor Ct11, with an equivalent voltage Vin / 4, charging the special phase inductor L2. Ordinary phase transformers Tr21-Tr27 discharge to the output terminal. Energy storage capacitor Ct... 25 and energy storage capacitor Ct35 are connected in series, with an equivalent voltage Vin / 4, charging the primary side of ordinary phase transformer Tr34. Ordinary phase transformers Tr31, Tr32, Tr33, Tr35, Tr36, and Tr37 discharge to the output terminal. Energy storage capacitor Ct31, with an equivalent voltage Vin / 4, charges special phase inductor L4, and ordinary phase transformers Tr41-Tr47 discharge to the output terminal. The output terminal Vout voltage is 0.75V, realizing a 48V-0.75V voltage conversion. Ignoring the effect of dead time, under steady-state conditions, it can be derived that:

[0085]

[0086] Among them, V in V is the input voltage. o L is the output voltage, and L is the value of the special phase inductance. m This is the magnetizing inductance value of a typical phase transformer.

[0087] The results were:

[0088]

[0089] Where T is the switching period.

[0090] For the total ripple value ΔI of the inductor current Lsum As shown in equation (5):

[0091]

[0092] It can be seen that, Figure 6 Mode 4 and Figure 3 The conclusions for mode one are the same, and the working modes are similar.

[0093] Figure 7 Figure 8 The simulated dynamic response waveform of the converter is given when the load current decreases from 1200A to 1000A at a rate of 1000A / μs. It can be seen that the output voltage overshoot is only 13.98mV, which is about 1.86%.

[0094] Figure 9 Figure 10 The simulation waveform of the dynamic response of the converter is given when the load current increases from 1000A to 1200A at a rate of 1000A / μs. It can be seen that the output voltage drop is only 27.52mV, which is about 3.67%.

[0095] As can be seen from the above analysis, the current waveforms of the special phase inductors L1-L4 are consistent and the ripple is small; the primary current waveforms of each ordinary phase transformer have a phase difference and the ripple is greater than that of the current waveform of the special phase inductor; this hybrid converter can meet the high current power supply requirement of 1200A from 48V bus to 0.75V.

[0096] according to Figure 1 By examining the connection relationship between the primary and secondary sides of a common phase transformer, it can be observed that the current in the special phase inductor flows through the secondary side of the common phase transformer. As a result, the DC components of the magnetic flux generated by the primary current and the current in the special phase inductor flowing through the secondary side can cancel each other out, leaving only the AC component that can cause core saturation. Therefore, the core volume of a common phase transformer can be significantly reduced without easily causing core saturation.

[0097] according to Figure 1 Each of the four-stage special-phase power supply unit PS, the six four-stage ordinary-phase power supply units P1-P6, and the one four-stage final-phase power supply unit PN contains three energy storage capacitors. Their presence ensures current balance between each stage of the power supply unit. This current balance is achieved because the charges on the energy storage capacitors must remain balanced, meaning their steady-state average voltage must be constant. Taking the four-stage special-phase power supply unit PS as an example, if the current in special-phase inductor L1 is greater than the current in special-phase inductor L2, the voltage across Ct11 and Ct12 will increase. This will decrease the average voltage of the phase switching node where special-phase inductor L1 is located, while simultaneously increasing the average voltage of the phase switching node where special-phase inductor L2 is located. Consequently, the current in special-phase inductor L1 decreases, and the current in special-phase inductor L2 increases. Similarly, any current imbalance between any two adjacent stages of this power supply unit will be automatically balanced according to this mechanism.

[0098] In summary, this invention achieves a high conversion ratio of 48V-0.75V by expanding the duty cycle of the drive waveform and reducing the inductor current ripple, thus meeting the requirements for a high conversion ratio.

[0099] It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any simple modifications made to the above embodiments based on the technical essence of the present invention are also within the protection scope of the present invention. Other equivalent changes and modifications are still within the scope of the technical solution of the present invention.

Claims

1. A hybrid converter with a large turns ratio inductor-transformer, characterized in that, include: A four-stage special phase power supply unit PS is used to distribute the input voltage evenly among the stages of each power supply unit through energy storage capacitors, thereby reducing the voltage stress on each switching transistor. Six four-stage ordinary phase power supply units P1 to P6 and one four-stage final phase power supply unit PF are used to reduce the equivalent inductance of each power supply unit during the dynamic load change process. Through magnetic flux cancellation, the transformer volume of the ordinary phase power supply unit is reduced. Each of the four-level special phase power supply unit PS, the four-level ordinary phase power supply units P1 to P6, and the four-level last phase power supply unit PF is equipped with three energy storage capacitors. The energy storage capacitors are used to balance the current between each stage of each power supply unit so that the steady-state average voltage is constant. The four-level special phase power supply unit PS is electrically connected to the four-level ordinary phase power supply units P1 to P6 and the four-level last phase power supply unit PF respectively. The four-level special phase power supply unit PS, the four-level ordinary phase power supply units P1 to P6 and the four-level last phase power supply unit PF are all electrically connected to the input terminal Vin of the converter. The four-level last phase power supply unit PF is electrically connected to the output terminal Vout of the converter. The four-stage special phase power supply unit PS includes: switching transistors S11, S21, S31, S41, S12, S22, S32, and S42; energy storage capacitors Ct11, Ct21, and Ct31; and special phase inductors L1, L2, L3, and L4. The circuit connection of the four-stage special phase power supply unit PS is as follows: one end of switching transistor S11 is connected to the input terminal Vin of the converter; the other end of switching transistor S11 is connected to one end of switching transistor S21 and one end of energy storage capacitor Ct11; the other end of energy storage capacitor Ct11 is connected to one end of switching transistor S12 and one end of special phase inductor L1; and the other end of switching transistor S12 is connected to… The other end of the switching transistor S21 is connected to one end of the switching transistor S31 and one end of the energy storage capacitor Ct21. The other end of the energy storage capacitor Ct21 is connected to one end of the switching transistor S22 and one end of the special phase inductor L2. The other end of the switching transistor S22 is grounded. The other end of the switching transistor S31 is connected to one end of the switching transistor S41 and one end of the energy storage capacitor Ct31. The other end of the energy storage capacitor Ct31 is connected to one end of the switching transistor S32 and one end of the special phase inductor L3. The other end of the switching transistor S32 is grounded. The other end of the switching transistor S41 is connected to one end of the switching transistor S42 and one end of the special phase inductor L4. The other end of the switching transistor S42 is grounded.

2. The hybrid converter with a large-ratio inductor-transformer according to claim 1, characterized in that, The four-level ordinary phase power supply units P1 to P6 each include: switching transistors S1x, S2x, S3x, S4x, switching transistors S1y, S2y, S3y, S4y, energy storage capacitors Ct1z, Ct2z, Ct3z, and ordinary phase transformers Tr1w, Tr2w, Tr3w, Tr4w, where x is 3, 5, 7, 9, 11, 13, z is 2, 3, 4, 5, 6, 7 respectively, y=x+1, w=z-1; The circuit connection of the four-stage ordinary phase power supply units P1 to P6 is as follows: one end of the switching transistor S1x is connected to the input terminal Vin of the converter; the other end of the switching transistor S1x is simultaneously connected to one end of the switching transistor S2x and one end of the energy storage capacitor Ct1z; the other end of the energy storage capacitor Ct1z is connected to one end of the switching transistor S1y and one end of the primary side of the ordinary phase transformer Tr1w; the other end of the switching transistor S1y is grounded; and the other end of the primary side of the ordinary phase transformer Tr1w is connected to the output terminal Vout. The other end of the switching transistor S2x is connected to one end of the switching transistor S3x and one end of the energy storage capacitor Ct2z; the other end of the energy storage capacitor Ct2z is connected to one end of the switching transistor S2y and the primary side of the ordinary phase transformer Tr2w. One end of the switch S22 is grounded, and the other end of the primary side of the ordinary phase transformer Tr2w is connected to the output terminal Vout; the other end of the switch S3x is connected to one end of the switch S4x and one end of the energy storage capacitor Ct3z, and the other end of the energy storage capacitor Ct3z is connected to one end of the switch S3y and one end of the primary side of the ordinary phase transformer Tr3w; the other end of the switch S32 is grounded, and the other end of the primary side of the ordinary phase transformer Tr3w is connected to the output terminal Vout; the other end of the switch S4x is connected to one end of the switch S4y and one end of the primary side of the ordinary phase transformer Tr4w, and the other end of the switch S4y is grounded, and the other end of the primary side of the ordinary phase transformer Tr4w is connected to the output terminal Vout. The end of the special phase inductor Ln that is not connected to the switching transistor is connected to one end of the secondary side of the ordinary phase transformer Trn1, where n=1, 2, 3, 4; the other end of the secondary side of the ordinary phase transformer Trn1 is connected in series with the secondary sides of ordinary phase transformer Trn2, ordinary phase transformer Trn3, ordinary phase transformer Trn4, and ordinary phase transformer Trn5, and then connected to one end of the secondary side of ordinary phase transformer Trn6.

3. A hybrid converter with a large-ratio inductor-transformer according to claim 2, characterized in that, The four-stage final phase power supply unit PF includes: switching transistors S115, S215, S315, S415, switching transistors S116, S216, S316, S416, energy storage capacitors Ct18, Ct28, Ct38, and ordinary phase transformers Tr17, Tr27, Tr37, Tr47. The circuit connection of the four-stage final-phase power supply unit PF is as follows: one end of the switch S115 is connected to the input terminal Vin of the converter; the other end of the switch S115 is connected to one end of the switch S215 and one end of the energy storage capacitor Ct18; the other end of the energy storage capacitor Ct18 is connected to one end of the switch S116 and one end of the primary side of the ordinary phase transformer Tr17; the other end of the switch S116 is grounded; the other end of the primary side of the ordinary phase transformer Tr17 is connected to the output terminal Vout; the other end of the switch S215 is connected to one end of the switch S315 and one end of the energy storage capacitor Ct28; the other end of the energy storage capacitor Ct28 is connected to one end of the switch S216 and one end of the primary side of the ordinary phase transformer Tr27. One end of the switching transistor S22 is grounded, and the other end of the primary winding of the ordinary phase transformer Tr27 is connected to the output terminal Vout; the other end of the switching transistor S315 is connected to one end of the switching transistor S415 and one end of the energy storage capacitor Ct38, and the other end of the energy storage capacitor Ct38 is connected to one end of the switching transistor S316 and one end of the primary winding of the ordinary phase transformer Tr37; the other end of the switching transistor S32 is grounded, and the other end of the primary winding of the ordinary phase transformer Tr37 is connected to the output terminal Vout; the other end of the switching transistor S415 is connected to one end of the switching transistor S416 and one end of the primary winding of the ordinary phase transformer Tr47, and the other end of the switching transistor S416 is grounded, and the other end of the primary winding of the ordinary phase transformer Tr47 is connected to the output terminal Vout; The other end of the secondary side of the ordinary phase transformer Trn6 is connected to one end of the ordinary phase transformer Trn7, and the other end of the ordinary phase transformer Trn7 is connected to the output terminal Vout.

4. A hybrid converter with a large-ratio inductor-transformer according to claim 3, characterized in that, The driving waveforms of the switching transistors S11, S31, S29, and S49 are the same, and the driving waveforms of the switching transistors S12, S32, S210, and S410 are the same; the driving waveforms of the switching transistors S11 and S12 are complementary. The driving waveforms of the switches S13, S33, S211, and S411 are the same, and the driving waveforms of the switches S14, S34, S212, and S412 are the same; the driving waveforms of the switches S13 and S14 are complementary; the driving waveform of the switch S13 lags behind the driving waveform of the switch S11 by 45°. The driving waveforms of the switches S15, S35, S213, and S413 are the same, and the driving waveforms of the switches S16, S36, S214, and S414 are the same; the driving waveforms of the switches S15 and S16 are complementary; the driving waveform of the switch S15 lags behind the driving waveform of the switch S11 by 90°. The driving waveforms of switches S17, S37, S215, and S415 are the same, and the driving waveforms of switches S18, S38, S216, and S416 are the same; the driving waveforms of switches S17 and S18 are complementary; the driving waveform of switch S17 lags behind the driving waveform of switch S11 by 135°. The driving waveforms of the switching transistors S19, S39, S21, and S41 are the same, the driving waveforms of the switching transistors S110, S310, S22, and S42 are the same, the driving waveforms of the switching transistors S19 and S110 are complementary, and the driving waveform of the switching transistor S19 lags behind the driving waveform of the switching transistor S11 by 180°. The driving waveforms of the switching transistors S111, S311, S23, and S43 are the same, the driving waveforms of the switching transistors S112, S312, S24, and S44 are the same, the driving waveforms of the switching transistors S111 and S112 are complementary, and the driving waveform of the switching transistor S111 lags behind the driving waveform of the switching transistor S112 by 225°. The driving waveforms of the switching transistors S113, S313, S25, and S45 are the same, and the driving waveforms of the switching transistors S114, S314, S26, and S46 are the same; the driving waveforms of the switching transistors S113 and S114 are complementary, and the driving waveform of the switching transistor S113 lags behind the driving waveform of the switching transistor S11 by 270°. The driving waveforms of the switching transistors S115, S315, S27, and S47 are the same, the driving waveforms of the switching transistors S116, S316, S28, and S48 are the same, the driving waveforms of the switching transistors S115 and S116 are complementary, and the driving waveform of the switching transistor S115 lags behind the driving waveform of the switching transistor S11 by 315°.

5. A hybrid converter with a large-ratio inductor-transformer according to claim 1, characterized in that, All the switching transistors in the converter are gallium nitride switching transistors.

6. A hybrid converter with a large turns ratio inductor-transformer according to claim 1, characterized in that, The driving waveform of the switching transistor in the converter is set with a dead time.

7. A hybrid converter with a large-ratio inductor-transformer according to claim 1, characterized in that, The duty cycle D of the drive waveform when the switching transistor in the converter is working is less than 0.

125.

8. A hybrid converter with a large-ratio inductor-transformer according to claim 1, characterized in that, The gain calculation formula for the converter is: （1） In equation (1), V in Indicates the input voltage. V out The output voltage is represented by , and D represents the duty cycle of the drive waveform.

9. A hybrid converter with a large-ratio inductor-transformer according to claim 1, characterized in that, The formula for calculating the total ripple value of the inductor current of the converter is: （2） In equation (2), V in Indicates the input voltage. V out D represents the output voltage, D represents the duty cycle of the drive waveform, and T represents the switching period. L Indicates the inductance value of a special phase. L m This represents the magnetizing inductance value of a typical phase transformer, Δ. I Lsum This represents the total ripple value of the inductor current.

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