Tandem switch coupling inductor direct current boost converter

Abstract

The invention discloses a series switch coupling inductor direct-current boost converter, solves the problem of limited boost capability of the existing direct-current boost converter, and belongs to the field of power electronic converters. The circuit comprises diodes D1-D5, an inductor unit L1, an inductor unit L2, coupling inductors N1-N2, a power switch tube S, a capacitor unit C1 and an output unit. When the power switch tube S is switched on, the direct-current voltage source supplies power to the output unit through the diode D2 and the coupling inductors N1-N2, meanwhile, the direct-current voltage source Vin charges the inductor units L1 and L2, and when the power switch tube S is switched off, the inductor units L1, L2 and the coupling inductors N1-N2 supply power to the output unit. The series switch coupling inductor direct-current boost converter provided by the invention can provide relatively high voltage gain.

Description

Technical Field

[0001] This invention relates to a series-coupled inductor DC-DC boost converter, belonging to the field of power electronic converters. Background Technology

[0002] Traditional DC-DC boost converters, such as those used in high-voltage converters, face significant challenges in achieving high voltage gain. As voltage gain requirements increase, the duty cycle of the switching transistors needs to be significantly increased. In high-voltage gain applications, the switching transistors and diodes experience substantial voltage and current stresses. This necessitates the use of power components with high voltage ratings and high current capacities, which not only increases cost but also leads to higher conduction losses due to the typically larger on-resistance of high-voltage devices. Consequently, their boost capability is quite limited, making them unsuitable for high-voltage gain DC-DC power conversion applications. Summary of the Invention

[0003] To address the limited boost capability of existing DC-DC boost converters, this invention provides a series-coupled inductor DC-DC boost converter that significantly improves boost inverter capability.

[0004] The present invention provides a series-coupled inductor DC-DC boost converter, characterized in that it comprises diodes D1-D5, inductor unit L1, inductor unit L2, coupled inductors N1-N2, power switch S, capacitor unit C1, and output unit;

[0005] The positive terminal of the DC voltage source is simultaneously connected to the anode of diode D4, the anode of diode D2, and one end of inductor unit L1; the other end of inductor unit L1 is simultaneously connected to the anode of diode D3 and the anode of diode D5.

[0006] The cathode of diode D3 is connected to one end of inductor unit L2 and the cathode of diode D4 at the same time;

[0007] The other end of the inductor unit L2 is connected to the cathode of diode D5, one end of capacitor unit C1, and the anode of diode D1.

[0008] The other end of capacitor C1 is connected to the positive terminal of coupling inductor N2;

[0009] The negative terminal of coupling inductor N2, the cathode of diode D2, and the positive terminal of coupling inductor N1 are connected simultaneously.

[0010] The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of the diode D1, the drain of the power switch S, and the positive terminal of the output unit.

[0011] The negative terminal of the DC voltage source, the negative terminal of the output unit, and the source terminal of the power switch S are connected simultaneously.

[0012] Preferably, the output unit includes an output diode D6 and an output capacitor unit C6;

[0013] The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of diode D1, the anode of output diode D6, and the drain of power switch S.

[0014] The cathode of the output diode D6 is connected to one end of the output capacitor unit C6 and one end of the load resistor R simultaneously;

[0015] The negative terminal of the DC voltage source, the other end of the output capacitor unit C6, the other end of the load resistor R, and the source of the power switch S are connected simultaneously.

[0016] Preferably, the voltage output gain is:

[0017]

[0018] Where D is the duty cycle of the power switch S when it is turned on. Let D be the turns ratio of the windings of the coupled inductor N2 to the coupled inductor N1, and let D range from (0,1).

[0019] The beneficial effects of this invention are that the converter of this application adopts a unique switched inductor impedance network to couple the main circuit and the DC voltage source. Compared with the classic Z-source inverter, this application significantly improves the boost inverter capability and enables continuous input current, which greatly reduces the risk of device damage. Attached Figure Description

[0020] Figure 1 This is a series-coupled inductor DC-DC boost converter;

[0021] Figure 2 This is the equivalent circuit diagram of a series-type switch-coupled inductor DC-Boost converter when the switch is turned on.

[0022] Figure 3 This is the equivalent circuit diagram of a series-type switch-coupled inductor DC-Boost converter when the switch is turned off.

[0023] Figure 4 DC input voltage V in =50V, waveform of output capacitor voltage;

[0024] Figure 5 shows the DC input voltage V. in =50V, output diode voltage and power switch voltage waveform;

[0025] Figure 6 DC input voltage V in =50V, voltage of diodes D2 and D1;

[0026] Figure 7DC input voltage V in =50V, capacitor unit voltage, inductor L2 current. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0030] The series-coupled inductor DC-DC boost converter of this embodiment includes diodes D1-D5, inductor unit L1, inductor unit L2, coupled inductors N1-N2, power switch S, capacitor unit C1, and output unit.

[0031] The positive terminal of the DC voltage source is simultaneously connected to the anode of diode D4, the anode of diode D2, and one end of inductor unit L1;

[0032] The other end of inductor unit L1 is connected to the anode of diode D3 and the anode of diode D5 simultaneously;

[0033] The cathode of diode D3 is connected to one end of inductor unit L2 and the cathode of diode D4 at the same time;

[0034] The other end of the inductor unit L2 is connected to the cathode of diode D5, one end of capacitor unit C1, and the anode of diode D1.

[0035] The other end of capacitor C1 is connected to the positive terminal of coupling inductor N2;

[0036] The negative terminal of coupling inductor N2, the cathode of diode D2, and the positive terminal of coupling inductor N1 are connected simultaneously.

[0037] The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of the diode D1, the drain of the power switch S, and the positive terminal of the output unit.

[0038] The negative terminal of the DC voltage source, the negative terminal of the output unit, and the source terminal of the power switch S are connected simultaneously.

[0039] The inductor unit L1, inductor unit L2, diode D3, diode D4, and diode D5 form a switching inductor. When the power switch S is turned on, the output voltage of the DC voltage source supplies power to the output unit through diode D2 and coupling inductors N1-N2. Simultaneously, the current voltage source V... in The inductor units L1 and L2 are charged. When the power switch S is turned off, the inductor units L1 and L2, and the coupled inductors N1-N2 supply power to the output unit. The series-type switched coupled inductor DC-DC boost converter of this application can provide a high voltage gain.

[0040] In a preferred embodiment, the output unit includes an output diode D6 and an output capacitor unit C6;

[0041] The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of diode D1, the anode of output diode D6, and the drain of power switch S.

[0042] The cathode of the output diode D6 is connected to one end of the output capacitor unit C6 and one end of the load resistor R simultaneously;

[0043] The negative terminal of the DC voltage source, the other end of the output capacitor unit C6, the other end of the load resistor R, and the source of the power switch S are connected simultaneously.

[0044] The working principle and process are as follows:

[0045] The control signal for the series-coupled switch-coupled inductor DC-DC boost converter in this application is V. gs It controls the switching on and off of the power switch S, and the winding current i of the coupling inductor. N1 i N2 The voltage V of diode D1 D1 The voltage V of diode D2 D2 The voltage V of diode D3 D3 The voltage V of diode D4 D4 The voltage V of diode D5 D5 The voltage V of capacitor unit C1 C1 The voltage V of output diode D6 D6 The power switch S operates in two modes: on and off, as described below:

[0046] When the power switch is turned on, the equivalent circuit is as follows: Figure 2 As shown, during this stage, the power switch S is turned on, and the DC voltage source V... in Directly connected to inductor unit L1, diode D3 is reverse-biased and cut off, while diodes D1, D2, D4, and D5 are turned on, and the DC voltage source V... in The DC voltage source V charges inductor units L1 and L2. inThe coupling inductor N1 is charged by diode D2, and the coupling inductors N1 and N2 charge the capacitor unit C1; diode D6 is reverse biased, and the output capacitor C6 independently supplies power to the load resistor R, thus ending this mode.

[0047] When the power switch is turned off, the equivalent circuit is as follows: Figure 3 As shown, the power switch S remains off, diodes D1, D2, D4, and D5 are reverse-biased and cut off, while diode D3 is forward-biased and conducts; inductor units L1 and L2, along with capacitor unit C1 and coupled inductors N1 and N2, supply power to the load resistor R and output capacitor C6 through diode D6, thus ending this mode.

[0048] From the above analysis, the gain expression can be obtained as follows:

[0049]

[0050] Where D is the duty cycle of the power switch SW. In the preferred embodiment, the operating range of D is (0,1), and the duty cycle is relatively low.

[0051] The turns ratio of the coupled inductor is In the preferred embodiment, n1=1.

[0052] The following experimental data illustrates the beneficial effects of adopting the structure of this application:

[0053] like Figure 4 As shown, the DC input voltage V in =50V, the output voltage is approximately V o =200V, n1=1, D=0.2, load R=200Ω. Figure 5 DC input voltage V in =50V, switching diode voltage, output diode voltage. Figure 6 DC input voltage V in =50V, voltage of diodes D2 and D1. Figure 7 DC input voltage V in =50V, output capacitor voltage, inductor unit L1 current. From Figures 4 to 7 It can be seen that the series-coupled inductor DC-DC boost converter has a very high voltage output gain.

[0054] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A series-coupled switch-coupled inductor DC-DC boost converter, characterized in that, It includes diodes D1-D5, inductor unit L1, inductor unit L2, coupling inductors N1-N2, power switch S, capacitor unit C1, and output unit; The positive terminal of the DC voltage source is simultaneously connected to the anode of diode D4, the anode of diode D2, and one end of inductor unit L1; the other end of inductor unit L1 is simultaneously connected to the anode of diode D3 and the anode of diode D5. The cathode of diode D3 is connected to one end of inductor unit L2 and the cathode of diode D4 at the same time; The other end of inductor unit L2 is connected to the cathode of diode D5, one end of capacitor unit C1, and the anode of diode D1; the other end of capacitor unit C1 is connected to the positive terminal of coupling inductor N2. The negative terminal of coupling inductor N2, the cathode of diode D2, and the positive terminal of coupling inductor N1 are connected simultaneously. The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of the diode D1, the drain of the power switch S, and the positive terminal of the output unit; the negative terminal of the DC voltage source, the negative terminal of the output unit, and the source of the power switch S are simultaneously connected.

2. The series-coupled switch-coupled inductor DC-DC boost converter according to claim 1, characterized in that, The output unit includes an output diode D6 and an output capacitor unit C6; The negative terminal of the coupling inductor N1 is simultaneously connected to the cathode of diode D1, the anode of output diode D6, and the drain of power switch S. The cathode of the output diode D6 is connected to one end of the output capacitor unit C6 and one end of the load resistor R simultaneously; The negative terminal of the DC voltage source, the other end of the output capacitor unit C6, the other end of the load resistor R, and the source of the power switch S are connected simultaneously.

3. The series-coupled switch-coupled inductor DC-DC boost converter according to claim 1, characterized in that, The voltage output gain is: Where D is the duty cycle of the power switch S when it is turned on. This represents the turns ratio of the windings of the coupled inductor N2 to the coupled inductor N1.

4. The series-coupled switch-coupled inductor DC-DC boost converter according to claim 3, characterized in that, The range of D is (0,1).

5. The series-coupled switch-coupled inductor DC-DC boost converter according to claim 4, characterized in that, 。

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