DC power supply and control method thereof
By alternating the control of the bridge arm switches of the DC-DC power supply, the difference in turn-off loss is adjusted, which solves the problems of uneven loss and uneven heat distribution in the prior art and achieves uniform loss distribution and heat balance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DELTA ELECTRONICS INC(CN)
- Filing Date
- 2025-10-21
- Publication Date
- 2026-05-22
AI Technical Summary
Existing DC power supplies suffer from significant power loss and uneven heat distribution when using phase offset control and delay time control.
By alternately controlling the primary-side switches of the first and second bridge arms, the turn-off loss difference is periodically adjusted to switch phase offset and delay time, thereby uniformly distributing the loss.
This achieves thermal balance in the DC-DC power supply, with losses evenly distributed across the device, thus reducing power consumption.
Smart Images
Figure CN122073435A_ABST
Abstract
Description
Technical Field
[0001] This case relates to a DC-DC power supply, and more particularly to a DC-DC power supply and its control method. Background Technology
[0002] Conventional DC-DC power supplies employ various control methods to manage the voltage gain in resonant converters. These include phase-shift control (PSC) and delay-time control (DTC). In phase-shift control, a phase shift is introduced between the first and second arms on the primary side of the converter. In delay-time control, a similar phase shift is introduced on the secondary side. However, DC-DC power supplies utilizing these conventional methods often exhibit significant power losses and uneven heat distribution.
[0003] Therefore, it is necessary to provide a DC power supply and its control method to solve the problems faced by the existing technology. Summary of the Invention
[0004] This invention provides a DC-DC power supply. The DC-DC power supply includes a controller. The controller architecture alternately controls the operation of two first primary-side switches of a first bridge arm and two second primary-side switches of a second bridge arm to periodically adjust the turn-off loss difference between the first and second primary-side switches. The phase offset and delay time between the first and second bridge arms are switched. The turn-off losses of the device are exchanged. Therefore, the thermal performance of the DC-DC power supply of this invention is balanced, and the losses are uniformly distributed across the device.
[0005] According to the concept of this application, a DC-DC power supply is provided. The DC-DC power supply includes a transformer, a primary circuit, a secondary circuit, and a controller. The transformer includes a primary winding and a secondary winding. The primary circuit is connected to the primary winding and includes a plurality of first primary switches and a plurality of second primary switches. The secondary circuit is connected to the secondary winding. The controller architecture is designed to alternately control the operation of the plurality of first primary switches and the plurality of second primary switches to periodically adjust a turn-off loss difference between the plurality of first primary switches and the plurality of second primary switches.
[0006] According to another concept of this application, a control method for a DC-DC power supply is provided. The DC-DC power supply includes a transformer, a primary circuit, and a secondary circuit. The primary circuit includes a plurality of first primary switches and a plurality of second primary switches. The control method includes the following steps: providing a controller to alternately control the operation of the plurality of first primary switches and the plurality of second primary switches in the primary circuit to periodically adjust a turn-off loss difference between the plurality of first primary switches and the plurality of second primary switches.
[0007] According to another concept of this invention, a DC-DC power supply is provided. The DC-DC power supply includes three transformers, a primary circuit, a secondary circuit, and a controller. Each of the three transformers includes a primary winding and a secondary winding. The primary circuit is connected to the primary winding and includes multiple first primary switches, multiple second primary switches, and multiple third primary switches. The secondary circuit is connected to the secondary winding and includes multiple first secondary switches, multiple second secondary switches, and multiple third secondary switches. The controller architecture is configured to alternately control the operation of the multiple first secondary switches, multiple second secondary switches, and multiple third secondary switches of the secondary circuit to periodically adjust a turn-off loss difference among the multiple first secondary switches, multiple second secondary switches, and multiple third secondary switches. Attached Figure Description
[0008] Figure 1 This is a schematic diagram of the circuit architecture of the DC-DC power supply in the first embodiment of this case.
[0009] Figure 2 It shows Figure 1 The timing diagram shows the turn-off loss state of the primary-side switch of the DC-DC power supply.
[0010] Figures 3A to 3F It shows Figure 1 The circuit diagram shown is illustrated in one embodiment of the DC-DC power supply, showing the operation of the primary-side switch and the secondary-side switch.
[0011] Figure 4A This shows what happens before controlling the primary-side switch. Figure 1 The waveforms of the primary-side switch, voltage, and current of each component of the DC-DC power supply are shown.
[0012] Figure 4B This shows what happens after controlling the primary-side switch. Figure 1 The waveforms of the primary-side switch, voltage, and current of each component of the DC-DC power supply are shown.
[0013] Figure 5 for Figure 1 The image shown is a thermal image of the primary-side switch of the DC-DC power supply.
[0014] Figure 6 It shows Figure 1 The diagram shows the loss waveform of the primary-side switch of the DC-DC power supply.
[0015] Figure 7 This is a circuit diagram illustrating a method for sensing. Figure 1 The sensing circuit of the primary-side switch of the DC-DC power supply is shown.
[0016] Figure 8 This is a schematic diagram of the circuit architecture of the DC-DC power supply in the second embodiment of this case.
[0017] Figures 9A to 9F Another embodiment is shown. Figure 1 The circuit diagram shown illustrates the operation of the primary and secondary switches of the DC-DC power supply.
[0018] Figure 10 It shows Figure 1 The diagram shows the primary and secondary switches of the DC-DC power supply, as well as the operating waveforms of the current in each component.
[0019] Figures 11A to 11F The circuit diagram shows the first resonator circuit of the primary side circuit and the second resonator circuit of the secondary side circuit of the DC-DC power supply in this case.
[0020] Figures 12A to 12E The circuit diagram shows the bridge arms of the primary circuit and the secondary circuit of the DC-DC power supply in this case.
[0021] Figure 13 This is a schematic diagram of the circuit architecture of the DC-DC power supply in the third embodiment of this case.
[0022] Figures 14A to 14D The circuit diagram shows... Figure 13 The bridge arms of the primary circuit and the secondary circuit of the DC-DC power supply shown are shown.
[0023] List of reference numerals
[0024] 1, 1a, 1b: DC power supply
[0025] 2, 2a, 2b, 2c, 2d, 2e, 2f: Transformers
[0026] 12a: First Transformer
[0027] 12b: Second transformer
[0028] 12c: Third transformer
[0029] 120: Transformer assembly
[0030] 21, 21a, 21b, 21c, 21d, 21e, 21f, 121: Primary winding
[0031] 22, 22a, 22b, 22c, 22d, 22e, 22f, 122: Secondary windings
[0032] 3. 130: Primary circuit
[0033] 31, 32, 41, 42, 44, 45, 46, 47, 131, 132, 141, 142, 144, 145, 146, 147: Bridge Arm
[0034] 33, 133: First resonator circuit
[0035] 4. 140: Secondary circuit
[0036] 43: Second resonator circuit
[0037] 5, 74, 150: Controller
[0038] 51: Phase Shift Control Unit
[0039] 52: Voltage and Current Detection Unit
[0040] 53: Time Processing Unit
[0041] 54: PWM Unit
[0042] 61: First voltage sensing unit
[0043] 62: Second voltage sensing unit
[0044] 63: Current sensing unit
[0045] 64: Drive circuit
[0046] 7: Sensing Circuit
[0047] 71: Sensing Components
[0048] 72: First Subtractor
[0049] 73: The Second Subtractor
[0050] A~H: Connecting nodes
[0051] C1, C2, C1e, C2e: Capacitors
[0052] Cin: Input capacitor
[0053] Co: Output capacitor
[0054] Cra, Crb, Crc, Crp: First resonant capacitor
[0055] Crs: Second resonant capacitor
[0056] D P First working cycle
[0057] 1-D P Second working cycle
[0058] fs: Frequency signal
[0059] HTOL: High turn-off loss
[0060] i Lr i m i P i Q1 i Q2 i s i SR1 i SR2 Current
[0061] Io_FB: Output current
[0062] Lra, Lrb, Lrc, Lrp, Lrp1, Lrp2: First resonant inductor
[0063] Lma, Lmb, Lrm, Lmc: Second resonant inductor
[0064] Lsa, Lsb, Lsc, Lrs: Third resonant inductor
[0065] LTOL: Low Turn-Off Loss
[0066] M1~M6: Operating Mode
[0067] P1, P2: Turn-off losses
[0068] ΔP: Loss difference
[0069] Q1~Q6, Q1a~Q4a, Q1b~Q2b, Q1c~Q2c, Q1d~Q4d, Q1e~Q4e, Qpa1~Qpa2, Qpb1~Qpb2, Qpc1~Qpc2, Q11a~Q16a, Q11b~Q34b, Q11c~Q34c, Q11d~Q16d: Primary-side switches
[0070] SR1~SR4, SRa1~SRa4, SRb1~SRb4, SRc1~SRc4: Secondary switch
[0071] t, t0~t12: Time
[0072] Tperiod, T s :cycle
[0073] ΔT Ref Reference value
[0074] V AB Vbus_FB, Vo_FB: Voltage : Parameter signal Detailed Implementation
[0075] Some typical embodiments that embody the features and advantages of this invention will be described in detail in the following description. It should be understood that this invention can have various variations in different forms, all of which do not depart from the scope of this invention, and the descriptions and drawings therein are for illustrative purposes only and not for limiting this invention.
[0076] Figure 1 This is a schematic diagram of the circuit architecture of the DC-DC power supply in the first embodiment of this case. Figure 2 It shows Figure 1 The timing diagram shown illustrates the turn-off loss state of the primary-side switch of the DC-DC power supply. (See diagram for details.) Figure 1 As shown, the DC-DC power supply 1 includes a transformer 2, a primary circuit 3, a secondary circuit 4, an input capacitor Cin, an output capacitor Co, and a controller 5. The transformer 2 includes a primary winding 21 and a secondary winding 22. The primary circuit 3 is connected to the primary winding 21 of the transformer 2. The primary circuit 3 includes a first bridge arm 31, a second bridge arm 32, and a first resonant circuit 33. The first bridge arm 31 includes two first primary switches Q1 and Q2. The two first primary switches Q1 and Q2 are connected in series to form a first connection node A. The second bridge arm 32 is connected in parallel with the first bridge arm 31. The second bridge arm 32 includes two second primary switches Q3 and Q4. The two second primary switches Q3 and Q4 are connected in series to form a second connection node B. The first resonant circuit 33 includes a first resonant inductor Lrp, a second resonant inductor Lrm, and a first resonant capacitor Crup. The first resonant inductor Lrp, the second resonant inductor Lrm, and the first resonant capacitor Crp are connected sequentially between the first connection node A and the second connection node B. The second resonant inductor Lrm is connected in parallel with the primary winding 21 of the transformer 2.
[0077] Secondary circuit 4 is connected to the secondary winding 22 of transformer 2. Secondary circuit 4 includes a third bridge arm 41, a fourth bridge arm 42, and a second resonant circuit 43. The third bridge arm 41 includes two first secondary switches SR1 and SR2. The first secondary switches SR1 and SR2 are connected in series to form a third connection node C. The fourth bridge arm 42 is connected in parallel with the third bridge arm 41. The fourth bridge arm 42 includes two second secondary switches SR3 and SR4. The second secondary switches SR3 and SR4 are connected in series to form a fourth connection node D. The second resonant circuit 43 includes a third resonant inductor Lrs and a second resonant capacitor Crs. The third resonant inductor Lrs is connected between one end of the secondary winding 22 of transformer 2 and the third connection node C. The second resonant capacitor Crs is connected between the other end of the secondary winding 22 of transformer 2 and the fourth connection node D. The input capacitor Cin is connected in parallel with the first bridge arm 31 and the second bridge arm 32 of the primary circuit 3. The output capacitor Co is connected in parallel with the third bridge arm 41 and the fourth bridge arm 42 of the secondary circuit 4.
[0078] Controller 5 is connected to the first bridge arm 31 and the second bridge arm 32 of the primary-side circuit 3, and the third bridge arm 41 and the fourth bridge arm 42 of the secondary-side circuit 4. The controller 5 is configured to alternately control the operation of the two first primary-side switches Q1 and Q2 of the first bridge arm 31, the two second primary-side switches Q3 and Q4 of the second bridge arm 32, and the operation of the third bridge arm 41 and the fourth bridge arm 42 of the secondary-side circuit 4. Figure 2 As shown, during the first cycle, the two primary-side switches Q1 and Q2 of the first bridge arm 31 have high turn-off loss (HTOL), and the two primary-side switches Q3 and Q4 of the second bridge arm 32 have low turn-off loss (LTOL). During the second cycle, the two primary-side switches Q1 and Q2 of the first bridge arm 31 have low turn-off loss (LTOL), and the two primary-side switches Q3 and Q4 of the second bridge arm 32 have high turn-off loss (HTOL). In other words, the controller 5 is configured to alternately control the operation of the two primary-side switches Q1 and Q2 of the first bridge arm 31 and the two primary-side switches Q3 and Q4 of the second bridge arm 32 to periodically adjust the difference in turn-off loss between the two primary-side switches Q1 and Q2 and the two primary-side switches Q3 and Q4.
[0079] In this embodiment, the two first primary-side switches Q1 and Q2 of the first bridge arm 31 include a first sub-switch Q1 and a second sub-switch Q2. The two second primary-side switches Q3 and Q4 of the second bridge arm 32 include a third sub-switch Q3 and a fourth sub-switch Q4. The first secondary-side switches SR1 and SR2 of the third bridge arm 41 include a fifth sub-switch SR1 and a sixth sub-switch SR2. The two second secondary-side switches SR3 and SR4 of the fourth bridge arm 42 include a seventh sub-switch SR3 and an eighth sub-switch SR4.
[0080] Figures 3A to 3F It shows Figure 1 The circuit diagram shown illustrates the operation of the primary and secondary switches in one embodiment of the DC-DC power supply. Figures 3A to 3F As shown, Figure 1 The DC-DC power supply 1 shown has six operating modes for its primary and secondary switches.
[0081] The first operating mode M1 is displayed as follows: Figure 3A In the first operating mode M1, the first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be on. The second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be off.
[0082] The second operating mode M2 is displayed as follows: Figure 3B In the second operating mode M2, the second sub-switch Q2, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be on. The first sub-switch Q1, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be off.
[0083] The third operating mode M3 is displayed as follows: Figure 3C In the third operating mode M3, the second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be on. The first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be off.
[0084] The fourth operating mode, M4, is displayed. Figure 3D In the fourth operating mode M4, the first sub-switch Q1, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be on. The second sub-switch Q2, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be off.
[0085] The fifth operating mode, M5, is displayed. Figure 3EIn the fifth operating mode M5, the first sub-switch Q1, the third sub-switch Q3, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be on. The second sub-switch Q2, the fourth sub-switch Q4, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be off.
[0086] The sixth operating mode, M6, is displayed on... Figure 3F In the sixth operating mode M6, the second sub-switch Q2, the fourth sub-switch Q4, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be on. The first sub-switch Q1, the third sub-switch Q3, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be off.
[0087] Figure 4A This shows what happens before controlling the primary-side switch. Figure 1 The waveforms of the primary-side switch, voltage, and current of each component of the DC-DC power supply are shown. Figure 4B This shows what happens after controlling the primary-side switch. Figure 1 The diagram shows the operating waveforms of the primary-side switches and the voltage and current of each component in the DC-DC power supply. Figure 4A and Figure 4B As shown, the operation of the primary-side switch and the voltage V between the first connection node A and the second connection node B are illustrated in sequence. AB The current i of the resonant inductor Lr The current i of the first sub-switch Q1 Q1 and the current i of the second sub-switch Q2 Q2 .
[0088] At Figure 4A In the process, before the primary-side switch is controlled (e.g., before it is enabled or started), the control modes are sequentially: fourth mode M4, first mode M1, second mode M2, third mode M3, fourth mode M4, first mode M1, fifth mode M5, third mode M3, sixth mode M6, and first mode M1. Figure 4B In the process of controlling the primary-side switch, the control modes are sequentially: Mode 6 M6, Mode 1 M1, Mode 5 M5, Mode 3 M3, Mode 6 M6, Mode 1 M1, Mode 2 M2, Mode 3 M3, Mode 4 M4, Mode 1 M1, and Mode 2 M2. During the operation of the main switch, the system will... Figure 4A Multiple mode switches are performed between Figure 4B and other modes. For example, between times t0 and t1, and between t4 and t5. Figure 4A The fourth mode M4 switches to Figure 4B The sixth mode, M6. From time t2 to t3, Figure 4A The second mode M2 switches to Figure 4B The fifth mode, M5. From time t6 to t7, Figure 4AThe fifth mode M5 switches to Figure 4B The second mode, M2, occurs between time t8 and t9. Figure 4A The sixth mode of the M6 is switched to Figure 4B The fourth mode, M4.
[0089] At Figure 4B At time t2, the first mode M1 switches to the fifth mode M5. In other words, when the fifth sub-switch SR1 and the eighth sub-switch SR4 are controlled to be on and the sixth sub-switch SR2 and the seventh sub-switch SR3 are controlled to be off, the controller 5 controls the first sub-switch Q1 to be on, and the controller 5 switches the on state from the fourth sub-switch Q4 to the third sub-switch Q3. At time t4, the third mode M3 switches to the sixth mode M6. In other words, when the sixth sub-switch SR2 and the seventh sub-switch SR3 are controlled to be on and the fifth sub-switch SR1 and the eighth sub-switch SR4 are controlled to be off, the controller 5 controls the second sub-switch Q2 to be on, and the controller 5 switches the on state from the third sub-switch Q3 to the fourth sub-switch Q4.
[0090] like Figure 4A As shown, the operating cycle of the first sub-switch Q1 changes from time t0 to t2 to time t4 to t7, in other words, the operating cycle of the first sub-switch Q1 increases. The operating cycle of the fourth sub-switch Q4 changes from time t1 to t3 to time t5 to t6, in other words, the operating cycle of the fourth sub-switch Q4 decreases. The voltage V between the first connection node A and the second connection node B... AB The current i of the resonant inductor Lr For stability. The turning-off current of the first sub-switch Q1 decreases from high to low, and the turning-off current of the fourth sub-switch Q4 increases from low to high. The voltage V between the first connection node A and the second connection node B. AB and the current i of the resonant inductor Lr It remains stable and free from any current ringing. Figure 4A In the process, before the primary-side switch is controlled, the first sub-switch Q1 is turned off at high current and the fourth sub-switch Q4 is turned off at low current. Figure 4B In this configuration, after the primary-side switch is controlled, the first sub-switch Q1 is turned off at low current and the fourth sub-switch Q4 is turned off at high current. After a specific cycle, the phase shift and delay time between the first bridge arm 31 and the second bridge arm 32 are switched. The turn-off losses of the device are exchanged. Therefore, the thermal performance of the DC-DC power supply 1 is balanced, and the losses are evenly distributed across the device.
[0091] Based on the above, the DC-DC power supply 1 of this invention includes a controller 5. The controller 5 is configured to alternately control the operation of the two first primary-side switches Q1 and Q2 of the first bridge arm 31 and the two second primary-side switches Q3 and Q4 of the second bridge arm 32, to periodically adjust the turn-off loss difference between the first primary-side switches Q1 and Q2 and the second primary-side switches Q3 and Q4. The phase offset and delay time between the first bridge arm 31 and the second bridge arm 32 are switched. The turn-off losses of the device are exchanged. Therefore, the thermal performance of the DC-DC power supply 1 is balanced, and the losses are evenly distributed across the device.
[0092] Figure 5 for Figure 1 The image shown is a thermal image of the primary-side switch of the DC-DC power supply. Figure 5 As shown, the four sub-switches of the DC-DC power supply 1 are mounted on the heat sink 6 and cooled by gas or liquid flow. Due to uneven heat distribution, the positions of the four sub-switches result in varying thermal states. These thermal differences may become more pronounced if additional mechanical layout factors are considered. The duty cycles of the four sub-switches can be adjusted to reduce losses.
[0093] Figure 6 It shows Figure 1 The diagram shows the loss waveform of the primary-side switch of a DC-DC power supply. Figure 6 As shown, in the first working cycle D P In the first sub-switch Q1 and the second sub-switch Q2, the first turn-off loss P2 is exhibited. During the second operating cycle (1-D... P In the diagram, the second primary-side switches Q3 and Q4 exhibit the second turn-off loss P1. P The value is between 0 and 1. The loss difference ΔP is formed between the first turn-off loss P2 and the second turn-off loss P1. During the first operating cycle D... P In the second duty cycle (1-D), the first turn-off loss P2 is greater than the second turn-off loss P1. P In the given equation, the first turn-off loss P2 is less than the second turn-off loss P1. The average losses of the first sub-switch Q1 and the second sub-switch Q2, and the average losses of the third sub-switch Q3 and the fourth sub-switch Q4, can be expressed by the following equations: This represents the average loss between the first sub-switch Q1 and the second sub-switch Q2. This represents the average loss of the third sub-switch Q3 and the fourth sub-switch Q4. The average loss can be adjusted by selecting different first duty cycles D. P and the second working cycle (1-D) P Adjust the value of ) to determine the first working cycle D.P and the second working cycle (1-D) P This can be used as a control variable to adjust the average loss, thereby making the thermal performance adjustable. Therefore, the operating cycle of each control mode within a single cycle can be effectively changed.
[0094] In some embodiments, the duty cycle may be provided by the temperature of the sensing device. Figure 7 This is a circuit diagram illustrating a method for sensing. Figure 1 The sensing circuit of the primary-side switch of the DC-DC power supply is shown. For example... Figure 7 As shown, the DC-DC power supply 1 includes a sensing circuit 7. The sensing circuit 7 includes at least two sensing components 71, a first subtractor 72, a second subtractor 73, and a controller 74. The two sensing components 71 sense corresponding primary-side switches to provide two sensing signals respectively. The first subtractor 72 subtracts the colder of the two sensing signals from the hotter one to provide a first difference. The second subtractor 73 calculates a reference value ΔT. Ref The first difference is subtracted to provide a second difference. Controller 74 processes the second difference to provide a duty cycle to the primary-side switch. In some embodiments, controller 74 is... Figure 1 It consists of controller 5.
[0095] Figure 8 This is a schematic diagram of the circuit architecture of the DC-DC power supply according to the second embodiment of this case. Figure 8 As shown, with Figure 1 Compared to the DC-DC power supply 1, the controller 5 of the DC-DC power supply 1a in this embodiment includes a phase offset control unit 51, a voltage and current detection unit 52, a time processing unit 53, and a pulse width modulation (PWM) unit 54. The phase offset control unit 51 detects the output voltage Vo_FB, the bus voltage Vbus_FB, and the output current Io_FB at the output terminal of the DC-DC power supply 1a and outputs parameter signals. The voltage and current detection unit 52 detects the output voltage Vo_FB and output current Io_FB of the DC-DC power supply 1a to output a frequency signal fs. The time processing unit 53 detects the frequency signal fs and parameter signals. To output update signals. PWM unit 54 detects parameter signals. The frequency signal fs and the update signal are used to output a PWM signal to control the operation of the first primary-side switches Q1 and Q2, the second primary-side switch Q3 and Q4 of the primary-side circuit 3, and the first secondary-side switches SR1 and SR2 and the second secondary-side switches SR3 and SR4 of the secondary-side circuit 4.
[0096] In some embodiments, the DC-DC power supply 1a includes a first voltage sensing unit 61, a second voltage sensing unit 62, a current sensing unit 63, and two drive circuits 64. The first voltage sensing unit 61 senses the input voltage of the DC-DC power supply 1a to output a bus voltage Vbus_FB. The second voltage sensing unit 62 senses the output voltage of the DC-DC power supply 1a to output an output voltage Vo_FB. The current sensing unit 63 senses the output current of the DC-DC power supply 1a to output an output current Io_FB. The two drive circuits 64 receive PWM signals to control the operation of the first primary-side switches Q1 and Q2, the second primary-side switches Q3 and Q4 of the primary-side circuit 3, and the first secondary-side switches SR1 and SR2 and the second secondary-side switches SR3 and SR4 of the secondary-side circuit 4.
[0097] Figures 9A to 9F Another embodiment is shown. Figure 1 The diagram shows the circuit diagram illustrating the operation of the primary and secondary switches of a DC-DC power supply. Figures 9A to 9F As shown, with Figures 3A to 3F Compared to the control modes M1 to M6 shown in the figure, the primary and secondary switches of the DC-DC power supply 1 have six other control modes.
[0098] The first operating mode M1 is displayed as follows: Figure 9A In the first operating mode M1, the first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be on. The second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be off.
[0099] The second operating mode M2 is displayed as follows: Figure 9B In the second operating mode M2, the second sub-switch Q2, the third sub-switch Q3, the fifth sub-switch SR1, and the seventh sub-switch SR3 are controlled to be on. The first sub-switch Q1, the fourth sub-switch Q4, the sixth sub-switch SR2, and the eighth sub-switch SR4 are controlled to be off.
[0100] The third operating mode M3 is displayed as follows: Figure 9C In the third operating mode M3, the second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the seventh sub-switch SR3 are controlled to be on. The first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the eighth sub-switch SR4 are controlled to be off.
[0101] The fourth operating mode, M4, is displayed. Figure 9DIn the fourth operating mode M4, the first sub-switch Q1, the fourth sub-switch Q4, the sixth sub-switch SR2, and the eighth sub-switch SR4 are controlled to be on. The second sub-switch Q2, the third sub-switch Q3, the fifth sub-switch SR1, and the seventh sub-switch SR3 are controlled to be off.
[0102] The fifth operating mode, M5, is displayed. Figure 9E In the fifth operating mode M5, the second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the eighth sub-switch SR4 are controlled to be on. The first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the seventh sub-switch SR3 are controlled to be off.
[0103] The sixth operating mode, M6, is displayed. Figure 9F In the sixth operating mode M6, the first sub-switch Q1, the fourth sub-switch Q4, the fifth sub-switch SR1, and the seventh sub-switch SR3 are controlled to be on. The second sub-switch Q2, the third sub-switch Q3, the sixth sub-switch SR2, and the eighth sub-switch SR4 are controlled to be off.
[0104] Figure 10 It shows Figure 1 The diagram shows the primary and secondary switches of the DC-DC power supply, as well as the operating waveforms of the current in each component. Figure 10 As shown, the operation of the primary-side switch, the operation of the secondary-side switch, and the current i through the first connection node A are illustrated in sequence. P The current i through the third connection node C Lr The current i of the second resonant inductor Lrm m The current i of the fifth sub-switch SR1 SR1 and the current i of the sixth sub-switch SR2 SR2 .At Figure 10 In this system, the control modes are, in order: Mode 4 M4, Mode 1 M1, Mode 2 M2, Mode 3 M3, Mode 4 M4, Mode 1 M1, Mode 5 M5, Mode 3 M3, Mode 6 M6, Mode 1 M1, Mode 5 M5, Mode 3 M3, Mode 6 M6, Mode 1 M1, Mode 5 M5, and Mode 3 M3.
[0105] In some embodiments, the first resonator circuit of the primary side circuit and the second resonator circuit of the secondary side circuit can be adjusted according to actual needs. Figures 11A to 11F The circuit diagram shows the first resonator circuit of the primary side and the second resonator circuit of the secondary side of the DC-DC power supply in this case. Figure 11AAs shown, the first resonant circuit, the second resonant circuit, and the transformer form an SRC structure. The first resonant circuit includes a first resonant inductor Lrp and a first resonant capacitor Crp. The first resonant inductor Lrp is connected to one end of the primary winding 21a of the transformer 2a. The first resonant capacitor Crp is connected to the other end of the primary winding 21a of the transformer 2a. The second resonant circuit does not contain any components.
[0106] like Figure 11B As shown, the first resonant circuit, the second resonant circuit, and the transformer form an LLC structure. The first resonant circuit includes a first resonant inductor Lrp, a second resonant inductor Lrm, and a first resonant capacitor Crup. The first resonant inductor Lrp is connected to one end of the primary winding 21b of the transformer 2b. The first resonant capacitor Crup is connected to the other end of the primary winding 21b of the transformer 2b. The second resonant inductor Lrm is connected in parallel with the primary winding 21b. The second resonant circuit does not contain any components.
[0107] like Figure 11C As shown, the first resonant circuit, the second resonant circuit, and the transformer form a CLLC structure. The first resonant circuit includes a first resonant inductor Lrp, a second resonant inductor Lrm, and a first resonant capacitor Crup. The first resonant inductor Lrp is connected to one end of the primary winding 21c of the transformer 2c. The first resonant capacitor Crup is connected to the other end of the primary winding 21c of the transformer 2c. The second resonant inductor Lrm is connected in parallel with the primary winding 21c. The second resonant circuit includes a third resonant inductor Lrs and a second resonant capacitor Crs. The third resonant inductor Lrs is connected to one end of the secondary winding 22c of the transformer 2c. The second resonant capacitor Crs is connected to the other end of the secondary winding 22c of the transformer 2c.
[0108] like Figure 11D As shown, the first resonant circuit, the second resonant circuit, and the transformer form a CLLC structure. The first resonant circuit includes a first resonant inductor Lrp, a second resonant inductor Lrm, and a first resonant capacitor Crup. The first resonant inductor Lrp is connected to one end of the primary winding 21d of the transformer 2d. The first resonant capacitor Crup is connected to the other end of the primary winding 21d of the transformer 2d. The second resonant inductor Lrm is connected in parallel with the primary winding 21d. The second resonant circuit includes a second resonant capacitor Crus. The second resonant capacitor Crus is connected to one end of the secondary winding 22d of the transformer 2d.
[0109] like Figure 11EAs shown, the first resonant circuit, the second resonant circuit, and the transformer form a CLL structure. The first resonant circuit includes a second resonant inductor Lrm and a first resonant capacitor Crp. The first resonant capacitor Crp is connected to one end of the primary winding 21e of the transformer 2e. The second resonant inductor Lrm is connected in parallel with the primary winding 21e. The second resonant circuit includes a third resonant inductor Lrs. The third resonant inductor Lrs is connected to one end of the secondary winding 22e of the transformer 2e.
[0110] like Figure 11F As shown, the first resonant circuit, the second resonant circuit, and the transformer form an LCL-T structure. The first resonant circuit includes two first resonant inductors Lrp1 and Lrp2 and a first resonant capacitor Crup. The two first resonant inductors Lrp1 and Lrp2 are connected in series with one end of the primary winding 21f of the transformer 2f. The first resonant capacitor Crup is connected between the two first resonant inductors Lrp1 and Lrp2 and the other end of the primary winding 21f of the transformer 2f. The second resonant circuit includes a second resonant capacitor Crus. The second resonant capacitor Crus is connected to one end of the secondary winding 22f of the transformer 2f.
[0111] In some embodiments, the structure of the bridge arms of the primary circuit and the secondary circuit can be adjusted as needed. Figures 12A to 12E The circuit diagram shows the bridge arms of the primary circuit and the secondary circuit of the DC-DC power supply in this case.
[0112] like Figure 12A As shown, the bridge arm of the primary-side circuit (or secondary-side circuit) forms a three-level circuit. The bridge arm contains four primary-side switches Q1a, Q2a, Q3a, and Q4a connected in series with ground. (See diagram below.) Figure 12B As shown, the bridge arms of the primary-side circuit (or secondary-side circuit) form a full-bridge circuit. Each bridge arm contains two primary-side switches Q1b and Q2b connected in series. For example... Figure 12C As shown, the bridge arms of the primary-side circuit (or secondary-side circuit) form a full-bridge circuit. Each bridge arm includes two primary-side switches Q1c and Q2c and two capacitors C1 and C2. The two primary-side switches Q1c and Q2c are connected in series. The two primary-side switches Q1c and Q2c are connected in parallel with the two capacitors C1 and C2. Figure 12D As shown, the bridge arms of the primary-side circuit (or secondary-side circuit) form a half-bridge circuit. Each bridge arm contains four primary-side switches Q1d, Q2d, Q3d, and Q4d. Two primary-side switches Q1d and Q2d are connected in series. Two primary-side switches Q3d and Q4d are connected in series. Two primary-side switches Q1d and Q2d are connected in parallel with two primary-side switches Q3d and Q4d. Figure 12EAs shown, the bridge arms of the primary-side circuit (or secondary-side circuit) form a stacked half-bridge circuit. Each bridge arm contains four primary-side switches Q1e, Q2e, Q3e, and Q4e connected in series, and two capacitors C1e and C2e. The four primary-side switches Q1e, Q2e, Q3e, and Q4e are connected in series. Capacitor C1e is connected in parallel with the two primary-side switches Q1e and Q2e. Capacitor C2e is connected in parallel with the two primary-side switches Q3e and Q4e.
[0113] Figure 13 This is a schematic diagram of the circuit architecture of the DC-DC power supply according to the third embodiment of this case. Figure 13 As shown, the DC-DC power supply 1b includes a transformer assembly 120, a primary circuit 130, a secondary circuit 140, an output capacitor Co, and a controller 150. The transformer assembly 120 includes a first transformer 12a, a second transformer 12b, and a third transformer 12c. Each transformer 12a, 12b, and 12c includes a primary winding 121 and a secondary winding 122. The primary circuit 130 is connected to the primary winding 121 of the transformers 12a, 12b, and 12c. The primary circuit 130 includes a first bridge arm 131, a second bridge arm 132, a third bridge arm 134, and a first resonant circuit 133. The first bridge arm 131 includes two first primary switches Qpa1 and Qpa2. The two first primary switches Qpa1 and Qpa2 are connected in series to form a first connection node A. The second bridge arm 132 is connected in parallel with the first bridge arm 131. The second bridge arm 132 includes two second primary switches Qpb1 and Qpb2. Two second primary-side switches, Qpb1 and Qpb2, are connected in series to form a second connection node B. The third bridge arm 134 is connected in parallel with the first bridge arm 131 and the second bridge arm 132. The third bridge arm 134 includes two third primary-side switches, Qpc1 and Qpc2. The two third primary-side switches, Qpc1 and Qpc2, are connected in series to form a third connection node C.
[0114] The first resonant circuit 133 includes three first resonant inductors Lra, Lrb, and Lrc, three second resonant inductors Lma, Lmb, and Lmc, and three first resonant capacitors Cra, Crb, and Crc. The first resonant capacitor Cra and the first resonant inductor Lra are connected in series between the first connection node A and one end of the primary winding 121 of transformer 12a. The second resonant inductor Lma is connected in parallel with the primary winding 121 of transformer 12a. The first resonant capacitor Crb and the first resonant inductor Lrb are connected in series between the second connection node B and one end of the primary winding 121 of transformer 12b. The second resonant inductor Lmb is connected in parallel with the primary winding 121 of transformer 12b. The first resonant capacitor Crc and the first resonant inductor Lrc are connected in series between the third connection node C and one end of the primary winding 121 of transformer 12c. The second resonant inductor Lmc is connected in parallel with the primary winding 121 of transformer 12c. The other end of the primary winding 121 of transformer 12a is connected to the other end of the primary winding 121 of transformer 12b and the other end of the primary winding 121 of transformer 12c.
[0115] The secondary circuit 140 is connected to the secondary winding 122 of transformers 12a, 12b, and 12c. The secondary circuit 140 includes a fourth bridge arm 141, a fifth bridge arm 142, a sixth bridge arm 144, a seventh bridge arm 145, an eighth bridge arm 146, a ninth bridge arm 147, and a second resonator circuit 143.
[0116] The fourth bridge arm 141 includes two first secondary side switches SRa1 and SRa2. The first secondary side switches SRa1 and SRa2 are connected in series to form the fourth connection node D. The fifth bridge arm 142 is connected in parallel with the fourth bridge arm 141. The fifth bridge arm 142 includes two first secondary side switches SRa3 and SRa4. The two first secondary side switches SRa3 and SRa4 are connected in series to form the fifth connection node E. The fifth connection node E is connected to one end of the secondary winding 122 of transformer 12a. The sixth bridge arm 144 is connected in parallel with the fourth bridge arm 141 and the fifth bridge arm 142. The sixth bridge arm 144 includes two second secondary side switches SRb1 and SRb2. The two second secondary side switches SRb1 and SRb2 are connected in series to form the sixth connection node F. The seventh bridge arm 145 is connected in parallel with the fourth bridge arm 141, the fifth bridge arm 142, and the sixth bridge arm 144. The seventh bridge arm 145 includes two second secondary side switches SRb3 and SRb4. These two switches are connected in series to form the seventh connection node G. The seventh connection node G is connected to one end of the secondary winding 122 of transformer 12b. The eighth bridge arm 146 is connected in parallel with the fourth bridge arm 141, the fifth bridge arm 142, the sixth bridge arm 144, and the seventh bridge arm 145. The eighth bridge arm 146 includes two third secondary side switches SRc1 and SRc2. These two switches are connected in series to form the eighth connection node H. The ninth bridge arm 147 is connected in parallel with the fourth bridge arm 141, the fifth bridge arm 142, the sixth bridge arm 144, the seventh bridge arm 145, and the eighth bridge arm 146. The ninth bridge arm 147 includes two third secondary side switches SRc3 and SRc4. These switches are connected in series to form the tenth connection node I. The tenth connection node I is connected to one end of the secondary winding 122 of transformer 12c.
[0117] The second resonant circuit 143 includes three third resonant inductors Lsa, Lsb, and Lsc. The third resonant inductor Lsa is connected between the fourth connection node D and the other end of the secondary winding 122 of transformer 12a. The third resonant inductor Lsb is connected between the sixth connection node F and the other end of the secondary winding 122 of transformer 12b. The third resonant inductor Lsc is connected between the eighth connection node H and the other end of the secondary winding 122 of transformer 12c.
[0118] sure Figures 11A to 11F The structure shown can replace transformers 12a, 12b, and 12c, and can... Figures 12A to 12E The structure shown replaces the bridge arm of the secondary circuit. In some embodiments, the structure of the bridge arm of the primary circuit can be adjusted as needed. Figures 14A to 14D The circuit diagram shows... Figure 13The diagram shows the bridge arms of the primary and secondary circuits of a DC-DC power supply. For example... Figure 14A As shown in Figure 14D, the primary circuit is a cascaded stack circuit, a three-phase three-level circuit, or a simplified three-phase three-level circuit. Its detailed structure will not be described here.
[0119] Based on the above, the DC-DC power supply of this invention includes a controller. The controller architecture alternately controls the operation of the two first primary-side switches of the first bridge arm and the two second primary-side switches of the second bridge arm to periodically adjust the turn-off loss difference between the first and second primary-side switches. The phase offset and delay time between the first and second bridge arms are switched. The turn-off losses of the device are exchanged. Therefore, the thermal performance of the DC-DC power supply of this invention is balanced, and the losses are evenly distributed across the device.
[0120] This case may be modified in various ways by those skilled in the art, but all of them shall not deviate from the protection sought by the appended claims.
Claims
1. A DC-DC power supply, comprising: A transformer consists of a primary winding and a secondary winding; A primary-side circuit, connected to the primary-side winding, and including a plurality of first primary-side switches and a plurality of second primary-side switches; A secondary circuit, connected to the secondary winding; and A controller is configured to alternately control the operation of a plurality of first primary-side switches and a plurality of second primary-side switches to periodically adjust a turn-off loss difference between the plurality of first primary-side switches and the plurality of second primary-side switches.
2. The DC-DC power supply as claimed in claim 1, wherein the secondary circuit includes a plurality of first secondary switches and a plurality of second secondary switches.
3. The DC-DC power supply as claimed in claim 2, wherein the plurality of first primary-side switches include a first sub-switch and a second sub-switch, the plurality of second primary-side switches include a third sub-switch and a fourth sub-switch, the plurality of first secondary-side switches include a fifth sub-switch and a sixth sub-switch, and the plurality of second secondary-side switches include a seventh sub-switch and an eighth sub-switch.
4. The DC-DC power supply as claimed in claim 3, wherein when the fifth sub-switch and the eighth sub-switch are turned on and the sixth sub-switch and the seventh sub-switch are turned off, the controller controls the first sub-switch to turn on, and the controller switches the turn-on from the fourth sub-switch to the third sub-switch.
5. The DC-DC power supply as claimed in claim 3, wherein when the sixth sub-switch and the seventh sub-switch are turned on and the fifth sub-switch and the eighth sub-switch are turned off, the controller controls the second sub-switch to turn on, and the controller switches the turn-on from the third sub-switch to the fourth sub-switch.
6. The DC-DC power supply of claim 1, wherein the plurality of first primary-side switches exhibit a first turn-off loss, the plurality of second primary-side switches exhibit a second turn-off loss, a loss difference is formed between the first turn-off loss and the second turn-off loss, wherein in a first operating cycle the first turn-off loss is greater than the second turn-off loss, and in a second operating cycle the first turn-off loss is less than the second turn-off loss.
7. The DC-DC power supply as claimed in claim 1, wherein the controller comprises: A phase offset control unit detects an output voltage, a bus voltage and an output current of the DC-DC power supply to output a parameter signal; as well as A voltage and current detection unit detects the output voltage and the output current to output a frequency signal.
8. The DC-DC power supply of claim 7, wherein the controller comprises: A time processing unit detects the frequency signal and the parameter signal to output an update signal; as well as A PWM unit detects the parameter signal, the frequency signal, and the update signal to output a PWM signal to control the operation of the plurality of first primary-side switches and the plurality of second primary-side switches in the primary-side circuit.
9. A control method applicable to a DC-DC power supply, the DC-DC power supply including a transformer, a primary circuit and a secondary circuit, the primary circuit including a plurality of first primary switches and a plurality of second primary switches, the control method comprising: A controller is provided to alternately control the operation of the plurality of first primary-side switches and the plurality of second primary-side switches of the primary-side circuit to periodically adjust a turn-off loss difference between the plurality of first primary-side switches and the plurality of second primary-side switches.
10. The control method of claim 9, wherein the secondary-side circuit includes a plurality of first secondary-side switches and a plurality of second secondary-side switches, the plurality of first primary-side switches include a first sub-switch and a second sub-switch, the plurality of second primary-side switches include a third sub-switch and a fourth sub-switch, the plurality of first secondary-side switches include a fifth sub-switch and a sixth sub-switch, and the plurality of second secondary-side switches include a seventh sub-switch and an eighth sub-switch, wherein the control method further includes: When the fifth sub-switch and the eighth sub-switch are connected and the sixth sub-switch and the seventh sub-switch are disconnected, the controller controls the first sub-switch to be connected, and the controller switches the connection from the fourth sub-switch to the third sub-switch.
11. The control method of claim 9, wherein the secondary-side circuit includes a plurality of first secondary-side switches and a plurality of second secondary-side switches, the plurality of first primary-side switches include a first sub-switch and a second sub-switch, the plurality of second primary-side switches include a third sub-switch and a fourth sub-switch, the plurality of first secondary-side switches include a fifth sub-switch and a sixth sub-switch, and the plurality of second secondary-side switches include a seventh sub-switch and an eighth sub-switch, wherein the control method further includes: When the sixth sub-switch and the seventh sub-switch are connected and the fifth sub-switch and the eighth sub-switch are disconnected, the controller controls the second sub-switch to be connected, and the controller switches the connection from the third sub-switch to the fourth sub-switch.
12. The control method of claim 9, wherein the plurality of first primary-side switches exhibit a first turn-off loss, the plurality of second primary-side switches exhibit a second turn-off loss, a loss difference is formed between the first turn-off loss and the second turn-off loss, wherein in a first operating cycle, the first turn-off loss is greater than the second turn-off loss, and in a second operating cycle, the first turn-off loss is less than the second turn-off loss.
13. The control method of claim 12, wherein a first average loss of the plurality of first primary-side switches during the first working cycle is a first loss of the plurality of first primary-side switches minus the product of the first working cycle and the loss difference, and a second average loss of the plurality of second primary-side switches during the second working cycle is a second loss of the plurality of second primary-side switches minus the product of the second working cycle and the loss difference.
14. The control method of claim 9, wherein the control method further comprises: The controller alternately controls the operation of the plurality of first secondary-side switches and the plurality of second secondary-side switches of the secondary-side circuit.
15. The control method of claim 9, wherein the control method further comprises: A phase offset control unit is provided to detect an output voltage, a bus voltage, and an output current of the DC-DC power supply to output a parameter signal; and A voltage and current detection unit is provided to detect the output voltage and the output current to output a frequency signal.
16. The control method of claim 15, wherein the control method further comprises: Provide a time processing unit to detect the frequency signal and the parameter signal to output an update signal; and A PWM unit is provided to detect the parameter signal, the frequency signal, and the update signal to output a PWM signal to control the operation of the plurality of first primary-side switches and the plurality of second primary-side switches of the primary-side circuit.
17. A DC-DC power supply, comprising: Three transformers, each of which includes a primary winding and a secondary winding; A primary-side circuit, connected to the primary-side winding, includes multiple first primary-side switches, multiple second primary-side switches, and multiple third primary-side switches; A secondary circuit, connected to the secondary winding, includes a plurality of first secondary switches, a plurality of second secondary switches, and a plurality of third secondary switches; and A controller is configured to alternately control the operation of a plurality of first secondary-side switches, a plurality of second secondary-side switches, and a plurality of third secondary-side switches of the secondary-side circuit to periodically adjust a turn-off loss difference among the plurality of first secondary-side switches, a plurality of second secondary-side switches, and a plurality of third secondary-side switches.
18. The DC-DC power supply as claimed in claim 17, wherein the primary-side circuit is a cascaded stack circuit, a three-phase three-level circuit, or a simplified three-phase three-level circuit.
19. The DC-DC power supply of claim 17, wherein the DC-DC power supply includes a plurality of resonant circuits, each of the resonant circuits being connected to a corresponding transformer, wherein each of the resonant circuits and the corresponding transformer forms an SRC, an LLC, a CLLLC, a CLLC, a CLL, or an LCL-T circuit.
20. The DC-DC power supply as claimed in claim 17, wherein the secondary circuit is a full-bridge circuit, a half-bridge circuit, a stacked half-bridge circuit, or a three-level circuit.