DC-DC conversion device

Abstract

The utility model discloses a DC-DC conversion device which comprises a DC-DC power supply module (1) and a coupling power supply module (2), the DC-DC power supply module (1) comprises an energy storage inductor La, a DC-DC power supply control sub-module (11) for controlling the voltage of the output end Ta2 of the energy storage inductor La, and a diode d1 for follow current of the energy storage inductor La; the coupling power supply module (2) comprises a coupling inductor Lb, a rectifier diode d2 and an energy storage capacitor C02, the positive electrode of the rectifier diode d2 is electrically connected with the current output end Tb2 of the coupling inductor Lb, the negative electrode of the rectifier diode d2 is electrically connected with the positive electrode of the energy storage capacitor C02, and the negative electrode of the energy storage capacitor C02 is electrically connected with the current input end Tb1 of the coupling inductor Lb; the DC-DC power supply module is characterized in that the DC-DC power supply module (1) uses a first coil La contained in the coupling inductance element L as an energy storage inductor of the DC-DC power supply module, and the coupling power supply module (2) uses a second coil Lb contained in the coupling inductance element L as an energy coupling inductor of the coupling power supply module. The circuit is simple and low in cost.

Description

Technical Field

[0001] The utility model relates to the technical field of direct current switching power supplies, in particular to a DC-DC conversion device. Background Art

[0002] In the networking application or battery charging application of photovoltaic power generation components, in order to improve the efficiency of power transmission, it is necessary to make the DC conversion circuit in the optimizer or charger used by the photovoltaic components work in a direct-on state under specific conditions. The DC conversion circuit includes a BUCK step-down circuit or a BOOST step-up circuit. The direct-on state is to make the upper bridge arm switch tube in the DC-DC converter exit the pulse conduction state of PWM control and enter the continuous conduction state, so that the input power can reach the output end of the DC-DC converter through the continuously conducted upper bridge arm switch tube.

[0003] The technologies related to the direct-through mode of the DC-DC converter disclosed in the existing patent applications are as follows:

[0004] The circuit given in the application number CN202310112423.1 and the invention name "An input voltage feedforward control circuit of a dual-tube Buck-Boost converter" includes a power circuit and a control circuit. The control circuit includes an MPPT closed-loop control circuit, a pass-through mode judgment circuit, a mode selection circuit and a drive control circuit. The control circuit enables the dual-tube Buck-Boost converter to switch quickly and smoothly between the buck-boost mode and the pass-through mode, ensuring that the converter has high conversion efficiency and good stability in a wide input and output voltage range; the introduction of the pass-through mode can reduce the switching loss of the converter and further improve the conversion efficiency of the circuit. A dual closed-loop control method with input voltage feedforward is adopted. When the circuit performs MPPT conversion in the buck-boost mode, the input voltage is stabilized at the maximum power point through negative feedback regulation, thereby suppressing the influence of the input voltage disturbance on the output voltage, improving the dynamic response rate of the circuit, and ensuring that the converter has good stability in the entire input voltage range.

[0005] The application number is CN202310533411.6, and the invention name is "BOOST converter, chip and electronic device". The disclosed BOOST converter includes: a pass-through mode detection circuit, a clock control circuit, an error amplifier circuit, a pass-through mode dynamic clamping circuit, a current mirror, a duty cycle modulation circuit and a power stage circuit; the pass-through mode detection circuit provides a working mode signal of the BOOST converter according to the first reference voltage and the feedback voltage fed back by the power stage circuit; the error amplifier circuit provides a steady-state voltage according to the second reference voltage and the feedback voltage; the current mirror scales the upper tube sampling current fed back by the power stage circuit into a first load sampling current and a second load sampling current respectively; the pass-through mode dynamic clamping circuit sets the upper clamping voltage of the steady-state voltage to a first voltage value obtained based on the second load sampling current in the pass-through mode, and sets the upper clamping voltage of the steady-state voltage to a second voltage value in the normal boost mode.

[0006] Although the above patent application discusses the through state of the BUCK and BOOST circuits, it does not provide a specific power supply circuit structure of the upper bridge arm switch tube of the BUCK and BOOST circuits in the through mode. The utility model provides a DC-DC conversion device that can provide driving power for the upper bridge arm switch tube of the DC-DC conversion circuit in the through mode, and the circuit is simple and low in cost. Summary of the invention

[0007] The utility model aims to provide a circuit structure which can provide driving power for an upper bridge arm switch tube of a DC-DC conversion circuit in a direct-through mode, and the circuit is simple and low in cost.

[0008] To achieve this purpose, the utility model adopts the following technical solutions:

[0009] A DC-DC conversion device comprises a DC-DC power supply module (1) and a coupled power supply module (2), wherein the DC-DC power supply module (1) comprises an energy storage inductor La, and an output terminal T of the energy storage inductor La is controlled. a2 The DC-DC power supply control submodule (11) of the voltage is a diode d1 for the freewheeling of the energy storage inductor La; the coupling power supply module (2) includes a coupling inductor Lb, a rectifier diode d2, an energy storage capacitor C 02 , the positive electrode of the rectifier diode d2 and the current output terminal T of the coupling inductor Lb b2 Electrical connection, the cathode of the rectifier diode D2 and the energy storage capacitor C 02 The positive electrode of the energy storage capacitor C 02 The negative electrode of the coupled inductor Lb and the current input terminal T b1 Electrical connection; characterized in that:

[0010] The DC-DC power module (1) uses a first coil La included in a coupled inductor element L as an energy storage inductor of the DC-DC power module, and the coupled power module (2) uses a second coil Lb included in the coupled inductor element L as an energy coupling inductor of the coupled power module.

[0011] The beneficial effects of the utility model are:

[0012] The DC-DC conversion device provided by the utility model can provide driving power for the upper bridge arm switch tube of the DC-DC conversion circuit in the direct-through mode, and has a simple circuit and low cost.

[0013] The DC-DC converter provided by the utility model has the ability to provide power to local or in-machine electronic circuits, and also has the ability to provide isolated power to drive the upper bridge arm switch tube to remain on for the BUCK circuit or BOOST circuit in the through state.

[0014] Other features and advantages of the present invention will be described in the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of a DC-DC converter device according to a specific embodiment of the utility model.

[0016] Figure 2 The utility model is a schematic diagram of a DC-DC converter providing power to a BUCK circuit switch tube in a direct-through mode.

[0017] In the figure, 1. DC-DC power supply module; 11. DC-DC power supply control module; 2. Coupling power supply module; 3. Driving module; 4. PWM waveform generation module; 5. Measurement module. DETAILED DESCRIPTION

[0018] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0019] The utility model provides a DC-DC conversion device, which has the ability to provide power to local or in-machine electronic circuits, and also has the ability to provide isolated power to drive the upper bridge arm switch tube to remain on for the BUCK circuit or BOOST circuit in the through state.

[0020] The utility model provides a DC-DC conversion device, comprising a DC-DC power supply module (1) and a coupling power supply module (2), wherein the DC-DC power supply module (1) comprises an energy storage inductor La, and controls an output terminal T of the energy storage inductor La. a2The DC-DC power supply control submodule (11) of the voltage is a diode d1 for the freewheeling of the energy storage inductor La; the coupling power supply module (2) includes a coupling inductor Lb, a rectifier diode d2, an energy storage capacitor C 02 , the positive electrode of the rectifier diode d2 and the current output terminal T of the coupling inductor Lb b2 Electrical connection, the cathode of the rectifier diode D2 and the energy storage capacitor C 02 The positive electrode of the energy storage capacitor C 02 The negative electrode of the coupled inductor Lb and the current input terminal T b1 Electrical connection; characterized in that:

[0021] The DC-DC power module (1) uses a first coil La included in a coupled inductor element L as an energy storage inductor of the DC-DC power module, and the coupled power module (2) uses a second coil Lb included in the coupled inductor element L as an energy coupling inductor of the coupled power module.

[0022] Specifically, the DC-DC power module (1) is used to provide power to local or in-machine electronic circuits. For example, in a BUCK circuit or a BOOST circuit, the voltage V output by the DC-DC power module (1) out Used to provide working power to the microcontroller, upper and lower bridge arm switch tubes, and voltage or current measurement circuits in the BUCK circuit or BOOST circuit.

[0023] See also Figure 1 As shown, the DC-DC power supply module (1) uses the first coil La in the coupled inductor element L as an energy storage coil, uses the second coil Lb in the coupled inductor element L as an energy coupling coil, and uses the energy coupling coil to construct a coupled power supply module (2), so that the DC-DC conversion device provided by the utility model has the ability to provide power to local or in-machine electronic circuits, and also has the ability to provide an isolated power supply to the BUCK circuit or BOOST circuit in the through state to drive the upper bridge arm switch tube to remain on.

[0024] The DC-DC power supply module (1) includes a DC-DC power supply control submodule (11), further including a switch tube Q1, a switch tube drive circuit, and a PWM waveform circuit; the switch tube Q1 controls the on and off of the magnetizing current of the first coil La, an electrical connection ho is provided between the switch tube drive circuit and the gate-source of the switch tube Q1, the electrical connection ho provides a gate-source voltage for controlling the on and off of the switch tube Q1, and the PWM waveform circuit controls the on and off duty cycle of the switch tube Q1.

[0025] Furthermore, the DC-DC power supply module (1) further comprises a diode d1 for freewheeling the first coil La, the diode d1 for freewheeling, the first coil La, a switch tube q1 and a capacitor C 01Form a basic BUCK circuit.

[0026] Furthermore, r1 and r2 are used to output the voltage V out The DC-DC power supply control submodule (11) includes a PWM waveform circuit according to the voltage V out The measurement results are used to adjust the duty cycle of the pwm waveform to achieve the voltage V out stability.

[0027] See also Figure 1 As shown, the coupled power module (2) includes a coupled inductor Lb, a rectifier diode d2, and an energy storage capacitor C 02 , the positive electrode of the rectifier diode d2 and the current output terminal T of the coupling inductor Lb b2 Electrical connection, the cathode of the rectifier diode D2 and the energy storage capacitor C 02 The positive electrode of the energy storage capacitor C 02 The negative electrode of the coupled inductor Lb and the current input terminal T b1 Electrical connection.

[0028] Furthermore, the coupling power module (2) comprises an energy storage capacitor C 02 The positive electrode is electrically connected to the output terminal VBOOT, and the energy storage capacitor C 02 The negative electrode is electrically connected to the output terminal VS;

[0029] Specifically, the output terminal VBOOT is electrically connected to the driving module (3), and the output terminal VS is electrically connected to the source of the upper bridge arm switch tube.

[0030] A specific implementation method for electrically connecting the output terminal VBOOT to the driving module (3) is: electrically connecting the output terminal VBOOT to the power input terminal of the upper bridge arm switch tube driving circuit included in the driving module (3); the power input terminal of the upper bridge arm switch tube driving circuit is the power input terminal of the switch circuit that controls the gate-source voltage of the upper bridge arm switch tube;

[0031] Specifically, the upper bridge arm switch tube driving circuit included in the driving module (3) is an upper bridge arm switch tube driving circuit of a BUCK circuit or a BOOST circuit;

[0032] The upper bridge arm switch tube is an upper bridge arm switch tube of a BUCK circuit or a BOOST circuit; Figure 1 Q1 given in the figure is the upper arm switch tube of the BUCK circuit, Q2 is the lower arm switch tube of the BUCK circuit, and the output terminals T1 and T2 are the output terminals of the BUCK circuit;

[0033] Will Figure 1When the output terminals T1 and T2 given in the figure are used as the power input terminals and the lower bridge arm switch tube Q2 is used as the magnetizing current control of the energy storage inductor, Q1, Q2 and the energy storage coil L1 in the figure form a BOOST circuit.

[0034] Figure 1 In the circuit, Q1 and Q2 are connected in parallel with bypass diodes D1 and D2 respectively.

[0035] The specific chip model of the DC-DC power supply control module (11) provided in this embodiment is HT7886.

[0036] The utility model provides a DC-DC converter, wherein:

[0037] The coupling power supply module (2) is used to provide driving power for the upper bridge arm switch tube of the BUCK circuit or BOOST circuit operating in the direct-through mode, so that the upper bridge arm switch tube of the BUCK circuit or BOOST circuit is kept in a long-on state. The specific electrical connection relationship is:

[0038] The energy storage capacitor C included in the coupling power module (2) 02 The positive electrode is electrically connected to the driving circuit of the upper bridge arm switch tube of the BUCK circuit or BOOST circuit, and the energy storage capacitor C 02 The negative electrode is electrically connected to the source of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit.

[0039] The utility model provides a DC-DC converter, wherein:

[0040] The coupling power module (2) includes an energy storage capacitor C 02 The positive electrode is electrically connected to the driving circuit of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit. The specific implementation method is:

[0041] Energy storage capacitor C 02 The positive electrode is electrically connected to the power input end of the switch circuit for controlling the gate-source voltage of the upper bridge arm switch tube included in the driving circuit of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit.

[0042] Specifically, the driving module 3 includes a driving circuit for an upper bridge arm switch tube of the BUCK circuit or BOOST circuit;

[0043] The driving circuit of the upper bridge arm switch tube of the BUCK circuit or BOOST circuit includes a switch circuit for controlling the gate-source voltage of the upper bridge arm switch tube;

[0044] The energy storage capacitor C 02The positive electrode of the energy storage capacitor C is electrically connected to the power input terminal of the switch circuit for controlling the gate-source voltage of the upper bridge arm switch tube included in the drive circuit of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit, that is, 02 The positive electrode is electrically connected to the power input end of the switch circuit that controls the gate-source voltage of the upper bridge arm switch tube.

[0045] Specifically, the power input terminal of the switch circuit for controlling the gate-source voltage of the upper bridge arm switch tube included in the driving circuit is the VBOOT terminal.

[0046] The switch tube driving module 3 provided by the present invention has a specific chip model of NSD1224 or LM5108.

[0047] The utility model provides a DC-DC converter, wherein:

[0048] The coupling power module (2) includes a second coil Lb connected to the positive electrode of the rectifier diode d2. b2 end, and the DC-DC power module (1) includes a capacitor C 01 The positive pole of the first coil La is electrically connected to T a2 The end is the same as the end of the same name.

[0049] A specific implementation method of using the coupling power module 2 to provide driving power for the upper bridge arm switch tube of the BUCK circuit in the pass-through mode, see Figure 2 As shown in the figure, the input end Ti of the inductor L1 is electrically connected to the source of the upper arm switch tube Q1 and the drain of the lower arm switch tube Q2, the output end To of the inductor L1 is electrically connected to the positive electrode of the output capacitor C1, the negative electrode of the bypass diode D3 and the positive output terminal T1 of the BUCK circuit, the negative output terminal T2 of the BUCK circuit is electrically connected to the positive electrode of the bypass diode D3, the negative electrode of the output capacitor C1 and the power ground line GND of the BUCK circuit, the bypass diode D1 is connected in parallel between the source and the drain of the upper arm switch tube Q1, the bypass diode D2 is connected in parallel between the source and the drain of the lower arm switch tube Q2, the input power supply of the BUCK circuit is a photovoltaic module, the photovoltaic module can be a photovoltaic panel or a series combination of multiple photovoltaic panels, the input power supply of the BUCK circuit can also be a battery or a power supply after AC / DC conversion.

[0050] exist Figure 2 In the BUCK circuit shown in FIG. 1 , after the PWM waveform generating module 4 sends a PWM waveform with a duty cycle of 1 to the driving module 3, the driving module 3 uses the isolated power supply provided by the coupling power supply module 2 to maintain a continuous high level between the gate and the source of the upper bridge arm switch tube Q1, so that the upper bridge arm switch tube Q1 remains in a continuous on state, achieving the input voltage V inDirect connection between the positive output terminal T1 of the BUCK circuit.

[0051] The measuring module 5 measures the voltage at the output terminal To of the energy storage coil and the input voltage of the BUCK circuit; the voltage measurement result of the output terminal To of the energy storage coil by the measuring module 5 is used as the basis for the PWM waveform generation module 4 to adjust the PWM waveform duty cycle, and the measurement result of the input voltage of the BUCK circuit is used as the basis for judging the performance of the photovoltaic panel.

[0052] The technical principle of the present invention is described above in combination with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations here, technicians in this field can think of other specific implementation methods of the present invention without creative work, and these methods will fall within the protection scope of the present invention.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any technician in the field of the present invention can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed by the present invention, but the scope of protection of the present invention shall be based on the definition of the attached claims.

[0054] The utility model provides a DC-DC conversion device, which overcomes the disadvantages of relatively complex circuits and high costs in the prior art, and has the ability to provide power to local or internal electronic circuits, and also has the ability to provide isolated power to drive the upper bridge arm switch tube to remain on for the BUCK circuit or BOOST circuit in the through state. The circuit is simple and the cost is low.

Claims

1. A DC-DC conversion device, comprising a DC-DC power supply module (1) and a coupling power supply module (2), wherein: The DC-DC power supply module (1) includes an energy storage inductor La, and controls the output terminal T of the energy storage inductor La. a2 The DC-DC power supply control submodule (11) of the voltage is a diode d1 for the freewheeling of the energy storage inductor La; the coupling power supply module (2) includes a coupling inductor Lb, a rectifier diode d2, an energy storage capacitor C 02 , the positive electrode of the rectifier diode d2 and the current output terminal T of the coupling inductor Lb b2 Electrical connection, the cathode of the rectifier diode D2 and the energy storage capacitor C 02 The positive electrode of the energy storage capacitor C 02 The negative electrode of the coupled inductor Lb and the current input terminal T b1 Electrical connection; characterized in that: The DC-DC power module (1) uses a first coil La included in a coupled inductor element L as an energy storage inductor of the DC-DC power module, and the coupled power module (2) uses a second coil Lb included in the coupled inductor element L as an energy coupling inductor of the coupled power module.

2. The DC-DC converter according to claim 1, wherein: The coupling power supply module (2) is used to provide driving power for the upper bridge arm switch tube of the BUCK circuit or BOOST circuit operating in the direct-through mode, so that the upper bridge arm switch tube of the BUCK circuit or BOOST circuit is kept in a long-on state. The specific electrical connection relationship is: The energy storage capacitor C included in the coupling power module (2) 02 The positive electrode is electrically connected to the driving circuit of the upper bridge arm switch tube of the BUCK circuit or BOOST circuit, and the energy storage capacitor C 02 The negative electrode is electrically connected to the source of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit.

3. The DC-DC converter according to claim 2, wherein: The coupling power module (2) includes an energy storage capacitor C 02 The positive electrode is electrically connected to the driving circuit of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit. The specific implementation method is: Energy storage capacitor C 02 The positive electrode is electrically connected to the power input end of the switch circuit for controlling the gate-source voltage of the upper bridge arm switch tube included in the driving circuit of the upper bridge arm switch tube of the BUCK circuit or the BOOST circuit.

4. The DC-DC converter according to claim 1, wherein: The coupling power module (2) includes a second coil Lb connected to the positive electrode of the rectifier diode d2. b2 end, and the DC-DC power module (1) includes a capacitor C 01 The positive pole of the first coil La is electrically connected to T a2 The end is the same as the end of the same name.

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