An adaptive driving circuit with wide load resonance and low ripple filtering

Abstract

This invention discloses an adaptive drive circuit with wide load resonance and low ripple filtering, including a DC supply unit, a startup and voltage regulation unit, an adaptive control unit, a bootstrap drive unit, an EMI suppression unit, an adaptive resonance unit, a drive chip, and a first resistor R1. Through the coordinated optimization of startup power supply, bootstrap drive, dead-time control, resonant network, and filtering architecture, and by adopting an innovative circuit structure and precise parameter matching, (1) it maintains efficient operation over a wide load range, meets the requirements of high power density power supplies, and reduces energy loss; (2) it accelerates startup speed, reduces the risk of drive failure, avoids shoot-through between upper and lower bridge arms, and extends the stable working time of the equipment; (3) it is compatible with wide input voltage and wide load fluctuation conditions, and can be applied to multiple fields without additional adjustments; (4) it effectively reduces bus ripple and electromagnetic interference, eliminates the need for additional filtering circuits, simplifies the system structure, controls costs, and enhances market competitiveness.

Description

Technical Field

[0001] This invention relates to the field of rectification and inversion technology, and in particular to an adaptive drive circuit with wide load resonance and low ripple filtering. Background Technology

[0002] In the field of switching power supplies, half-bridge LLC resonant converters are widely used in industrial power supplies, new energy equipment, and consumer electronics due to their advantages such as soft-switching characteristics, high conversion efficiency, and wide input voltage range. Currently, mainstream technical solutions include the following core modules: Input rectification and bus filtering typically employ a full-bridge rectifier circuit in conjunction with a large-capacity electrolytic capacitor to achieve DC bus output, relying on a single large-capacity capacitor to suppress ripple.

[0003] The startup power supply circuit often adopts an architecture of "resistor voltage divider + Zener diode + filter capacitor", which directly draws power from the DC bus to power the controller. The startup process relies on resistor current limiting charging.

[0004] In conventional bootstrap drive circuits, ordinary fast recovery diodes are used as bootstrap charging transistors. The charging of the bootstrap capacitor depends entirely on the conduction time of the lower bridge MOSFET, and the stability of the drive voltage is greatly affected by load fluctuations.

[0005] Resonant controllers and frequency control: Most controllers adopt a fixed dead time design and set the switching frequency through external resistors and capacitors (RT / CT). However, the dead time cannot be dynamically adjusted according to the load or bus voltage.

[0006] LLC resonant networks, traditionally designed with resonant cavity parameters (inductance, capacitance, resistance) optimized for rated load, lack adaptive adjustment capabilities over a wide load range.

[0007] However, the above technical solutions still have the following shortcomings: 1) Traditional starting circuits rely on high-resistance voltage divider resistors to limit current, resulting in slow capacitor charging, long start-up time, and even failure to start under low voltage. VCC power supply is only clamped by Zener diodes, and VCC ripple fluctuates greatly when the bus voltage fluctuates, which can easily lead to controller false reset or abnormality.

[0008] 2) Fast recovery diodes have large reverse recovery current, which increases losses and EMI in high-frequency scenarios; under light load, the bootstrap capacitor is not charged enough, the upper bridge MOSFET is not fully turned on, and the drive fails in extreme cases.

[0009] 3) Unable to adapt to load changes; excessively long dead zone under heavy load damages switching conditions; excessively short dead zone under light load increases the risk of bridge arm shoot-through.

[0010] 4) Fixed resonant parameters are optimal only under rated load. Switching losses increase and efficiency decreases under light load.

[0011] 5) The bus filter capacitor has a large high-frequency ESR and large ripple; the resonant cavity has strong noise, requiring additional filter circuits, which increases the size and cost. Summary of the Invention

[0012] To address the aforementioned technical problems, this invention proposes an adaptive drive circuit with wide load resonance and low ripple filtering, and puts forward a systematic optimization scheme of fast startup-adaptive drive-wide load resonance-low ripple filtering.

[0013] The technical solution used in this invention is as follows: an adaptive drive circuit with wide load resonance and low ripple filtering, comprising a DC supply unit 100, a startup and voltage regulation unit 200, an adaptive control unit 300, a bootstrap drive unit 400, an EMI suppression unit 500, an adaptive resonant unit 600, a drive chip 700, and a first resistor R1; the DC supply unit 100 is used to convert AC to DC to power other functional units; the startup and voltage regulation unit 200 is used to shorten startup time and stabilize VCC power supply; the adaptive control unit 300 is used to adapt to dynamic load changes and maintain soft switching; the bootstrap drive unit 400 is used to reduce high-frequency losses and ensure light-load drive; the EMI suppression unit 500 is used to reduce ripple and reduce electromagnetic interference; and the adaptive resonant unit 600 is used to adapt to wide loads and maintain soft switching.

[0014] Furthermore, the driver chip 700 is preferably a high-voltage half-bridge driver chip.

[0015] Furthermore, the driver chip 700 includes 8 pins.

[0016] Furthermore, the first end of the first resistor R1 is connected to the DC supply unit 100, and the second end of the first resistor R1 is connected to the startup and voltage regulation unit 200.

[0017] Further, the DC supply unit 100 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a capacitor C1, a first AC input terminal AC+, and a second AC input terminal AC-. The first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 form a bridge rectifier circuit to rectify the AC current from the first AC input terminal AC+ and the second AC input terminal AC- into DC current. The first end of the first diode D1 and the first end of the third diode D3 are connected to the first end of the capacitor C1 to form the positive terminal of the DC bus. The second end of the first diode D1 and the first end of the second diode D2 are connected to the first AC input terminal AC+. The second end of the third diode D3 and the first end of the fourth diode D4 are connected to the second AC input terminal AC-. The second end of the second diode D2, the second end of the fourth diode D4, and the second end of the capacitor C1 are connected to form the negative terminal of the DC bus. The negative terminal of the DC bus is connected to the fourth pin COM of the driver chip 700.

[0018] Further, the startup and voltage regulation unit 200 includes a fifth Schottky diode D5, a first Zener diode Z1, a second capacitor C2, and a third capacitor C3; the first terminal of the fifth Schottky diode D5, the first terminal of the first Zener diode Z1, the first terminal of the second capacitor C2, and the first terminal of the third capacitor C3 are connected to the second terminal of the first resistor R1; the second terminal of the fifth Schottky diode D5, the second terminal of the first Zener diode Z1, the second terminal of the second capacitor C2, and the second terminal of the third capacitor C3 are connected to the negative terminal of the DC bus; the third terminal of the fifth Schottky diode D5 is connected to one end of the adaptive resonant unit 600.

[0019] Furthermore, the adaptive control unit 300 includes a third resistor R2 and a fourth capacitor C4; the first end of the third resistor R2 and the first end of the fourth capacitor C4 are connected to the third pin CT of the driver chip 700; the second end of the third resistor R2 is connected to the second pin RT of the driver chip 700; and the second end of the fourth capacitor C4 is connected to the negative terminal of the DC bus.

[0020] Further, the bootstrap driving unit 400 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth diode D6, a sixth capacitor C6, a first MOSFET Q1, and a second MOSFET Q2; the first end of the third resistor R3 is connected to the first pin VCC of the driving chip 700, and the second end of the third resistor R3 is connected to the second end of the sixth diode D6; the first end of the sixth diode D6 and the first end of the sixth capacitor C6 are connected to the eighth pin VB of the driving chip 700; the second end of the sixth capacitor C6, the source of the first MOSFET Q1, the drain of the second MOSFET Q2, and the sixth pin VS of the driving chip 700 are connected to the other end of the adaptive resonant unit 600, forming an upper bridge floating reference terminal; the upper bridge floating reference terminal is connected to the upper and lower bridge MOSFETs and is used to cooperate with pins 7 and 8. The first MOSFET Q1 is connected to the seventh pin HO of the driver chip 700 through the fourth resistor R4, and the drain of the first MOSFET Q1 is connected to the positive terminal of the DC bus; the second MOSFET Q2 is connected to the fifth pin LO of the driver chip 700 through the fifth resistor R5, and the source of the second MOSFET Q2 is connected to the negative terminal of the DC bus.

[0021] Further, the EMI suppression unit 500 includes a sixth resistor R6, a seventh resistor R7, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, and a tenth capacitor C10; the first ends of the sixth resistor R6, the seventh capacitor C7, and the eighth capacitor C8 are connected to the positive terminal of the DC bus; the second ends of the sixth resistor R6, the seventh capacitor C7, and the eighth capacitor C8 are connected together, and the first ends of the seventh resistor R7, the ninth capacitor C9, and the tenth capacitor C10 are connected together to form a PWM pulse signal output terminal; the PWM pulse signal output terminal is connected to a power transformer for driving the IGBT module; the second ends of the seventh resistor R7, the ninth capacitor C9, and the tenth capacitor C10 are connected to the negative terminal of the DC bus.

[0022] Furthermore, the adaptive resonant unit 600 includes an eighth resistor R8, a ninth resistor R9, and a fifth capacitor C5; the first end of the eighth resistor R8 and the first end of the ninth resistor R9 are connected to the third end of the fifth Schottky diode D5; the second end of the eighth resistor R8 and the second end of the ninth resistor R9 are connected to the first end of the fifth capacitor C5; and the second end of the fifth capacitor C5 is connected to the inverter signal output terminal.

[0023] The beneficial effects of this invention compared with the prior art are as follows: By synergistic optimization of startup power supply, bootstrap drive, dead zone control, resonant network and filter architecture, and by adopting innovative circuit structure and precise parameter matching, (1) energy efficiency is significantly improved, maintaining high-efficiency operation in a wide load range, meeting the needs of high power density power supply and reducing energy loss; (2) the reliability of system operation is enhanced, startup speed is accelerated, the risk of drive failure is reduced, bridge arm shoot-through is avoided, and the stable working time of equipment is extended; (3) the scope of scene adaptation is broadened, and it can be compatible with wide input voltage and wide load fluctuation, and can be applied to multiple fields without additional adjustment; (4) cost and volume configuration is optimized, bus ripple and electromagnetic interference are effectively reduced, no additional configuration of related filter circuits is required, the system structure is simplified and the cost is controlled, and market competitiveness is enhanced. Attached Figure Description

[0024] Figure 1 This is a diagram of an adaptive driving framework with wide load resonance and low ripple filtering according to the present invention.

[0025] Figure 2 This is a diagram of an adaptive drive circuit with wide load resonance and low ripple filtering according to the present invention.

[0026] Reference numerals: 100-DC supply unit; 200-start-up and voltage regulation unit; 300-adaptive control unit; 400-bootstrap drive unit; 500-EMI suppression unit; 600-adaptive resonant unit; 700-drive chip. Detailed Implementation

[0027] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] The present application will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present application can be combined with each other.

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to 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. The present invention will now be described in detail with reference to the accompanying drawings: An adaptive drive circuit with wide load resonance and low ripple filtering, such as Figure 1 As shown, it includes a DC supply unit 100, a startup and voltage regulation unit 200, an adaptive control unit 300, a bootstrap drive unit 400, an EMI suppression unit 500, an adaptive resonant unit 600, a drive chip 700, and a first resistor R1.

[0030] The DC power supply unit 100 is used to convert AC to DC to power other functional units.

[0031] The startup and voltage regulation unit 200 is used to shorten the startup time and stabilize the VCC power supply.

[0032] It is understandable that the startup and voltage regulation unit 200 adopts a combination architecture of "Schottky diode + Zener diode + large-capacity energy storage capacitor" to replace the traditional resistor voltage divider startup scheme. The DC bus voltage charges the energy storage capacitor C2 through the low forward voltage drop Schottky diode D5. With the clamping of the 15V Zener diode Z1 and the redundant filtering path, the startup time is greatly shortened compared with the traditional scheme. The VCC ripple can be controlled within ±0.5V, successfully solving the startup failure and power supply instability problems in low input voltage scenarios.

[0033] The adaptive control unit 300 is used to adapt to dynamic load changes and maintain soft switching.

[0034] Understandably, based on the RT / CT dynamic adjustment mechanism of the driver chip 700, by precisely matching the parameters of resistor R3 and capacitor C4 to set a switching frequency of 68kHz, the dead time of the driver chip 700 is dynamically adjusted with the switching frequency. When the frequency increases (light load), the dead time decreases to avoid bridge arm shoot-through; when the frequency decreases (heavy load), the dead time increases to maintain zero-voltage switching (ZVS) conditions. Through precise matching of RT / CT parameters, the dead time is dynamically adapted to the load, thus resolving the contradiction that a fixed dead time cannot simultaneously achieve both heavy-load efficiency and light-load reliability.

[0035] The bootstrap drive unit 400 is used to reduce high-frequency losses and ensure light-load drive.

[0036] It is understood that the bootstrap drive unit 400 uses an ultrafast recovery diode D6 (trr < 10ns) as the bootstrap charging transistor, paired with a high-frequency ceramic bootstrap capacitor C6 (ESR < 10mΩ). When the lower bridge MOSFET Q2 is turned on, the capacitor charges rapidly. When the upper bridge MOSFET Q1 is turned on, the capacitor C6 stores energy to maintain VGS stable above 10V, significantly reducing high-frequency reverse recovery losses and EMI interference, ensuring reliable drive under light load conditions, and preventing MOSFET conduction failure.

[0037] The EMI suppression unit 500 is used to reduce ripple and reduce electromagnetic interference.

[0038] Understandably, the EMI suppression unit 500 employs a network architecture of multiple capacitors in parallel (electrolytic capacitor C7 / C8 + ceramic capacitor C9 / C10) plus RC damping, replacing the traditional single electrolytic capacitor filter. This significantly reduces the equivalent series resistance, keeping the bus ripple within 50mV. Combined with RC damping to suppress high-frequency spikes, it meets Class B electromagnetic compatibility standards, eliminates the need for additional EMI filtering circuits, and reduces system size and BOM cost.

[0039] The adaptive resonant unit 600 is used to adapt to a wide load and maintain soft switching.

[0040] It is understandable that the adaptive resonant unit 600 adopts a symmetrical resonant cavity architecture of "resistor R8 / R9 voltage divider + high-frequency capacitor C5", combined with transformer leakage inductance to optimize impedance characteristics. The resonant parameters are calibrated through simulation, maintaining a soft-switching state within a load range of 10%-100%. By optimizing the impedance characteristics of the resonant cavity through the symmetrical resistor voltage divider design, soft-switching maintenance under wide loads is achieved, resulting in a significant improvement in efficiency under light loads.

[0041] The driver chip 700 is preferably a high-voltage half-bridge driver chip.

[0042] The preferred driver chip 700 is the L6571 chip. The L6571 chip is a commonly used high-voltage half-bridge driver chip.

[0043] It is understood that the driver chip 700 includes a first pin VCC, a second pin RT, a third pin CT, a fourth pin COM, a fifth pin LO, a sixth pin VS, a seventh pin HO, and an eighth pin VB.

[0044] The first end of the first resistor R1 is connected to the DC power supply unit 100, and the second end of the first resistor R1 is connected to the start-up and voltage regulation unit 200.

[0045] like Figure 2 As shown, the DC power supply unit 100 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a capacitor C1, a first AC input terminal AC+, and a second AC input terminal AC-.

[0046] The first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 form a bridge rectifier circuit to rectify the AC power from the first AC input terminal AC+ and the second AC input terminal AC- into DC power.

[0047] The first terminal of the first diode D1 and the first terminal of the third diode D3 are connected to the first terminal of the capacitor C1 to form the positive terminal of the DC bus.

[0048] The second terminal of the first diode D1 and the first terminal of the second diode D2 are connected to the first AC input terminal AC+.

[0049] The second terminal of the third diode D3 and the first terminal of the fourth diode D4 are connected to the second AC input terminal AC-.

[0050] The second terminal of the second diode D2, the second terminal of the fourth diode D4, and the second terminal of the capacitor C1 are connected to form the negative terminal of the DC bus.

[0051] The negative terminal of the DC bus is connected to the fourth pin COM of the driver chip 700.

[0052] like Figure 2 As shown, the startup and voltage regulation unit 200 includes a fifth Schottky diode D5, a first Zener diode Z1, a second capacitor C2, and a third capacitor C3.

[0053] The first terminal of the fifth Schottky diode D5, the first terminal of the first Zener diode Z1, the first terminal of the second capacitor C2, and the first terminal of the third capacitor C3 are connected to the second terminal of the first resistor R1.

[0054] The second terminal of the fifth Schottky diode D5, the second terminal of the first Zener diode Z1, the second terminal of the second capacitor C2, and the second terminal of the third capacitor C3 are connected to the negative terminal of the DC bus.

[0055] The third terminal of the fifth Schottky diode D5 is connected to one end of the adaptive resonant unit 600.

[0056] like Figure 2 As shown, the adaptive control unit 300 includes a third resistor R2 and a fourth capacitor C4.

[0057] The first end of the third resistor R2 and the first end of the fourth capacitor C4 are connected to the third pin CT of the driver chip 700.

[0058] The second end of the third resistor R2 is connected to the second pin RT of the driver chip 700.

[0059] The second terminal of the fourth capacitor C4 is connected to the negative terminal of the DC bus.

[0060] like Figure 2As shown, the bootstrap driving unit 400 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth diode D6, a sixth capacitor C6, a first MOSFET Q1, and a second MOSFET Q2.

[0061] The first end of the third resistor R3 is connected to the first pin VCC of the driver chip 700, and the second end of the third resistor R3 is connected to the second end of the sixth diode D6.

[0062] The first terminal of the sixth diode D6 and the first terminal of the sixth capacitor C6 are connected to the eighth pin VB of the driver chip 700.

[0063] The second terminal of the sixth capacitor C6, the source of the first MOS transistor Q1, the drain of the second MOS transistor Q2, the sixth pin VS of the driver chip 700, and the other end of the adaptive resonant unit 600 are connected to form the upper bridge floating reference terminal.

[0064] The upper bridge floating reference terminal is connected to the upper and lower bridge MOS and is used to drive high-side power devices in conjunction with pins 7 and 8.

[0065] The gate of the first MOSFET Q1 is connected to the seventh pin HO of the driver chip 700 through the fourth resistor R4, and the drain of the first MOSFET Q1 is connected to the positive terminal of the DC bus.

[0066] The gate of the second MOSFET Q2 is connected to the fifth pin LO of the driver chip 700 through the fifth resistor R5, and the source of the second MOSFET Q2 is connected to the negative terminal of the DC bus.

[0067] like Figure 2 As shown, the EMI suppression unit 500 includes a sixth resistor R6, a seventh resistor R7, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, and a tenth capacitor C10.

[0068] The first end of the sixth resistor R6, the first end of the seventh capacitor C7, and the first end of the eighth capacitor C8 are connected to the positive terminal of the DC bus.

[0069] The second end of the sixth resistor R6, the second end of the seventh capacitor C7, and the second end of the eighth capacitor C8 are connected together, and the first end of the seventh resistor R7, the first end of the ninth capacitor C9, and the first end of the tenth capacitor C10 are connected together to form a PWM pulse signal output terminal.

[0070] The PWM pulse signal output terminal is connected to the power transformer and is used to drive the IGBT module.

[0071] The second terminal of the seventh resistor R7, the second terminal of the ninth capacitor C9, and the second terminal of the tenth capacitor C10 are connected to the negative terminal of the DC bus.

[0072] like Figure 2 As shown, the adaptive resonant unit 600 includes an eighth resistor R8, a ninth resistor R9, and a fifth capacitor C5.

[0073] The first terminal of the eighth resistor R8 and the first terminal of the ninth resistor R9 are connected to the third terminal of the fifth Schottky diode D5.

[0074] The second end of the eighth resistor R8 and the second end of the ninth resistor R9 are connected to the first end of the fifth capacitor C5.

[0075] The second terminal of the fifth capacitor C5 is connected to the inverter signal output terminal.

[0076] It should be noted that the specific principle of an adaptive drive circuit with wide load resonance and low ripple filtering is as follows: I. Startup Phase (Key Steps + Corresponding Units / Components) 1) DC bus establishment The AC input (AC+, AC-) is rectified by the full-bridge rectifier circuit (D1~D4) of the DC supply unit, and then filtered by the bus capacitor C1. The output is a stable DC bus voltage, which powers all subsequent units.

[0077] 2) Controller wake-up and VCC voltage regulation The DC bus charges the startup capacitor C2 through the Schottky diode D5 (the core component of the startup and voltage regulation unit), while the voltage is clamped by the first Zener diode Z1, and the power supply stability is optimized in conjunction with the redundant filter capacitor C3. When the voltage of C2 reaches the startup threshold (approximately 10V) of the driver chip (L6571), the controller wakes up and completes initialization, and the VCC ripple is controlled within ±0.5V.

[0078] 3) Bootstrapping-driven energy storage The controller drives the lower bridge MOSFET Q2 to conduct, and the DC bus voltage charges the bootstrap capacitor C6 through the ultra-fast recovery diode D6 (the core of the bootstrap drive unit). This completes the energy reserve for driving the upper bridge MOSFET Q1. The startup time is ≤225ms, and the startup phase ends.

[0079] II. Stable Operation Phase (Core Processes + Function Implementation) 1) Dynamic adjustment of switching frequency and dead time The L6571 driver chip sets a 68kHz reference switching frequency through the parameters of resistor R2 and capacitor C4 in the adaptive control unit, and the dead time dynamically adapts to the load. Under light load, the frequency increases, thus reducing the dead time (to avoid bridge arm shoot-through); under heavy load, the frequency decreases, thus increasing the dead time (to maintain soft-switching ZVS conditions).

[0080] 2) Alternating conduction and energy transfer of MOSFETs The driver chip outputs complementary drive signals from its HO / LO pins, which drive Q1 and Q2 to conduct alternately via resistors R4 (Q1 gate) and R5 (Q2 gate). When Q1 is on, the current path is "DC bus positive terminal → Q1 → adaptive resonant unit → DC bus negative terminal (ground)"; when Q2 is on, the current path is "ground → Q2 → adaptive resonant unit → return current to the bus". Both achieve zero-voltage switching (ZVS), significantly reducing high-frequency losses.

[0081] 3) Wide load resonance adaptation The adaptive resonant unit (R8 / R9 symmetrical voltage divider + high-frequency capacitor C5) combined with the transformer leakage inductance optimizes impedance characteristics and operates at the resonant frequency. It maintains soft-switching mode over a wide load range of 10% to 100%, ensuring efficient energy transfer.

[0082] 4) Ripple suppression and EMI control C6 provides power when Q2 is on and discharges when Q1 is on, maintaining the gate-source voltage (VGS) of Q1 stable above 10V to prevent light-load drive failure. The EMI suppression unit uses a multi-capacitor parallel architecture of "electrolytic capacitor C7 / C8 + ceramic capacitor C9 / C10" in conjunction with RC damping (R6, R7) to control the bus ripple within 50mV, meeting the Class B electromagnetic compatibility standard without the need for additional filtering circuits.

[0083] III. Shutdown Phase (Key Actions + Closing Procedures) 1) Termination of energy transfer When the controller detects a shutdown signal or an abnormal state, it stops outputting the HO / LO drive signal, and the upper bridge MOSFET Q1 and the lower bridge MOSFET Q2 are simultaneously turned off. This completely terminates power transfer in the circuit, preventing abnormal power consumption.

[0084] 2) Capacitor discharge and controller sleep mode The bootstrap capacitor C6, starting capacitor C2, and bus capacitor C1 discharge sequentially, releasing residual energy. The controller then enters sleep mode, preparing for the next startup and ensuring stability during the shutdown phase.

[0085] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platform, or the corresponding software can be implemented by hardware platform.

[0086] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application. Those skilled in the art will understand that the modules in the apparatus of the embodiment can be distributed within the apparatus of the embodiment as described, or they can be located in one or more apparatuses different from this embodiment, with corresponding changes. The modules of the above-described embodiment can be combined into one module, or further divided into multiple sub-modules.

[0087] The serial numbers in this application are for descriptive purposes only and do not represent the superiority or inferiority of any particular implementation scenario. The above disclosures are merely a few specific implementation scenarios of this application; however, this application is not limited thereto, and any variations conceived by those skilled in the art should fall within the protection scope of this application.

Claims

1. An adaptive drive circuit with wide load resonance and low ripple filtering, characterized in that, It includes a DC power supply unit (100), a startup and voltage regulation unit (200), an adaptive control unit (300), a bootstrap drive unit (400), an EMI suppression unit (500), an adaptive resonant unit (600), a driver chip (700), and a first resistor R1; The DC power supply unit (100) is used to convert AC to DC to power other functional units; The startup and voltage regulation unit (200) is used to shorten the startup time and stabilize the VCC power supply; The adaptive control unit (300) is used to adapt to dynamic load changes and maintain soft switching; The bootstrap drive unit (400) is used to reduce high-frequency losses and ensure light-load drive. The EMI suppression unit (500) is used to reduce ripple and reduce electromagnetic interference; The adaptive resonant unit (600) is used to adapt to a wide load and maintain soft switching.

2. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 1, characterized in that, The driving chip (700) is preferably a high-voltage half-bridge driving chip.

3. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 2, characterized in that, The driver chip (700) has 8 pins.

4. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 3, characterized in that, The first end of the first resistor R1 is connected to the DC power supply unit (100), and the second end of the first resistor R1 is connected to the start-up and voltage regulation unit (200).

5. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 4, characterized in that, The DC power supply unit (100) includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a capacitor C1, a first AC input terminal AC+, and a second AC input terminal AC-. The first diode D1, the second diode D2, the third diode D3 and the fourth diode D4 form a bridge rectifier circuit to rectify the AC power from the first AC input terminal AC+ and the second AC input terminal AC- into DC power. The first terminal of the first diode D1 and the first terminal of the third diode D3 are connected to the first terminal of the capacitor C1 to form the positive terminal of the DC bus. The second terminal of the first diode D1 and the first terminal of the second diode D2 are connected to the first AC input terminal AC+. The second terminal of the third diode D3 and the first terminal of the fourth diode D4 are connected to the second AC input terminal AC-. The second terminal of the second diode D2, the second terminal of the fourth diode D4, and the second terminal of the capacitor C1 are connected to form the negative terminal of the DC bus. The negative terminal of the DC bus is connected to the fourth pin COM of the driver chip (700).

6. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 5, characterized in that, The startup and voltage regulation unit (200) includes a fifth Schottky diode D5, a first Zener diode Z1, a second capacitor C2, and a third capacitor C3; The first terminal of the fifth Schottky diode D5, the first terminal of the first Zener diode Z1, the first terminal of the second capacitor C2, and the first terminal of the third capacitor C3 are connected to the second terminal of the first resistor R1. The second terminal of the fifth Schottky diode D5, the second terminal of the first Zener diode Z1, the second terminal of the second capacitor C2, and the second terminal of the third capacitor C3 are connected to the negative terminal of the DC bus. The third terminal of the fifth Schottky diode D5 is connected to one end of the adaptive resonant unit (600).

7. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 6, characterized in that, The adaptive control unit (300) includes a third resistor R2 and a fourth capacitor C4; The first end of the third resistor R2 and the first end of the fourth capacitor C4 are connected to the third pin CT of the driver chip (700); The second end of the third resistor R2 is connected to the second pin RT of the driver chip (700); The second terminal of the fourth capacitor C4 is connected to the negative terminal of the DC bus.

8. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 7, characterized in that, The bootstrap driving unit (400) includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth diode D6, a sixth capacitor C6, a first MOSFET Q1, and a second MOSFET Q2; The first end of the third resistor R3 is connected to the first pin VCC of the driver chip (700), and the second end of the third resistor R3 is connected to the second end of the sixth diode D6. The first terminal of the sixth diode D6 and the first terminal of the sixth capacitor C6 are connected to the eighth pin VB of the driver chip 700; The second terminal of the sixth capacitor C6, the source of the first MOS transistor Q1, the drain of the second MOS transistor Q2, the sixth pin VS of the driver chip (700) and the other end of the adaptive resonant unit (600) are connected to form the upper bridge floating reference terminal; The upper bridge floating reference terminal is connected to the upper and lower bridge MOS and is used to drive the high-side power devices in conjunction with pins 7 and 8. The gate of the first MOS transistor Q1 is connected to the seventh pin HO of the driver chip (700) through the fourth resistor R4, and the drain of the first MOS transistor Q1 is connected to the positive terminal of the DC bus. The gate of the second MOS transistor Q2 is connected to the fifth pin LO of the driver chip (700) through the fifth resistor R5, and the source of the second MOS transistor Q2 is connected to the negative terminal of the DC bus.

9. The adaptive drive circuit with wide load resonance and low ripple filtering according to claim 8, characterized in that, The EMI suppression unit (500) includes a sixth resistor R6, a seventh resistor R7, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, and a tenth capacitor C10. The first terminal of the sixth resistor R6, the first terminal of the seventh capacitor C7, and the first terminal of the eighth capacitor C8 are connected to the positive terminal of the DC bus. The second end of the sixth resistor R6, the second end of the seventh capacitor C7, and the second end of the eighth capacitor C8 are connected together, and the first end of the seventh resistor R7, the first end of the ninth capacitor C9, and the first end of the tenth capacitor C10 are connected together to form a PWM pulse signal output terminal. The PWM pulse signal output terminal is connected to the power transformer and used to drive the IGBT module; The second terminal of the seventh resistor R7, the second terminal of the ninth capacitor C9, and the second terminal of the tenth capacitor C10 are connected to the negative terminal of the DC bus.

10. An adaptive drive circuit with wide load resonance and low ripple filtering according to claim 9, characterized in that, The adaptive resonant unit (600) includes an eighth resistor R8, a ninth resistor R9, and a fifth capacitor C5; The first terminal of the eighth resistor R8 and the first terminal of the ninth resistor R9 are connected to the third terminal of the fifth Schottky diode D5. The second end of the eighth resistor R8 and the second end of the ninth resistor R9 are connected to the first end of the fifth capacitor C5; The second terminal of the fifth capacitor C5 is connected to the inverter signal output terminal.

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