CN115714533B - High-gain X-source direct-current boost converter based on coupling inductance voltage doubling unit and control method - Google Patents
High-gain X-source direct-current boost converter based on coupling inductance voltage doubling unit and control method Download PDFInfo
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Abstract
The invention provides a high-gain X-source direct current boost converter based on a coupling inductance voltage doubling unit and a control method. Belongs to the technical field of power electronic converters. The high-gain X-source direct-current boost converter based on the coupling inductance voltage doubling unit comprises a direct-current voltage source, two coupling inductance voltage doubling units and an X-source structure. Each coupling inductance voltage doubling unit comprises a coupling inductance, a diode and a capacitor, and the X source structure consists of two crossed switches. The high-gain X source direct current boost converter based on the coupling inductance voltage doubling unit greatly improves voltage gain and realizes continuous input current.
Description
Technical Field
The invention belongs to the technical field of power electronic converters, and particularly relates to a high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit and a control method.
Background
The boost converter is widely applied to a front-stage converter of a distributed power system to realize the boost function. The traditional Boost converter circuit topology is a Boost circuit, in theory, the voltage gain of the Boost circuit increases along with the increase of the duty ratio, however, in consideration of the parasitic equivalent series impedance in the actual circuit, the actual gain of the Boost circuit does not always become larger along with the increase of the duty ratio, so that the Boost capability of the Boost circuit is very limited, the Boost circuit is not suitable for high-gain direct-current power conversion occasions, and the switching voltage is the same as the output voltage, so that a power switch with low on resistance cannot be used, and the system cost and loss are increased.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides a high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit and a control method.
The invention is realized by the following technical scheme, the invention provides a high-gain X source direct current boost converter based on a coupling inductance voltage doubling unit, and the converter specifically comprises: DC voltage source V in Power switch SW 1 Capacitance C 1 Diode D 1 Coupled inductor winding N 2 Coupled inductor winding N 1 Output diode D o Power switch SW 2 Output capacitance C o Resistor R, capacitor C 2 Diode D 2 Coupled inductor winding N 4 And a coupling inductance winding N 3 ；
DC voltage source V in Positive electrode of (a) and power switch SW 1 Drain electrode of (C) and capacitor (C) 1 Cathode, diode D of (2) 1 Is connected with the positive electrode of the battery; capacitor C 1 Positive pole of (a) and coupling inductance winding N 2 Is connected with the positive electrode of the battery; diode D 1 Is coupled to the cathode of the inductor winding N 1 Is connected with the positive electrode of the battery; coupling inductance winding N 1 Is coupled to the cathode of the inductor winding N 2 Cathode, output diode D o Is provided, and power switch SW 2 Is connected with the drain electrode of the transistor; output diode D o Cathode and output capacitance C of (2) o The positive electrode of the resistor R is connected with one end of the resistor R; output capacitor C o Cathode of resistor R, other end of resistor R, power switch SW 1 Source, capacitance C of (2) 2 Cathode, diode D of (2) 2 Is connected with the positive electrode of the battery; capacitor C 2 Positive pole of (a) and coupled inductance winding N 4 The positive electrode of diode D is connected with 2 Cathode of (a) and coupled inductor winding N 3 Is connected with the positive electrode of the battery; coupling inductance winding N 3 Is coupled to the cathode of the inductor winding N 4 Cathode of (d) DC voltage source V in Cathode of (d) and power switch SW 2 Is connected to the source of the (c).
The invention provides a control method of a high-gain X-source direct-current boost converter based on a coupling inductance voltage-multiplying unit gs Simultaneously controlling the power switch SW 1 And SW 2 Is connected with the power supply; the whole control process is divided into 4 switching modes, namely a switching mode 1, a switching mode 2, a switching mode 3 and a switching mode 4.
Further, the switching mode 1 corresponds to a time period [ t ] 1 ,t 2 ]At this stage, the power switch tube is turned on, the DC voltage V in Through diode D 1 And a power switch tube SW 2 To the coupled inductor winding N 1 Charging, coupling inductance winding N due to magnetic induction principle 1 And N 2 Through diode D 2 Give electric capacity C 1 Charging;at the same time, the DC voltage passes through the diode D 2 And a power switch tube SW 1 To the coupled inductor winding N 3 Charging, coupling inductance winding N due to magnetic induction principle 3 And N 4 Through diode D 2 Give electric capacity C 2 Charging; output diode D o Reverse bias, output capacitance C o The load resistor R is independently powered and mode 1 ends.
Further, the switching mode 2 corresponds to a time period [ t ] 2 ,t 3 ]At this stage, the power switch tube SW 1 And SW 2 Turn-off, DC voltage V in Respectively give power switch SW 1 And SW 2 And two coupled inductor windings N 1 、N 2 、N 3 、N 4 Charging, modality 2 ends.
Further, the switching mode 3 corresponds to a time period [ t ] 3 ,t 4 ]Power switch tube SW 1 And SW 2 Remain off, diode D 1 And D 2 Turn-off, DC voltage V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o Supplying power when two coupled inductor winding currents i N1 、i N3 When it is minimized, modality 3 ends.
Further, the switching mode 4 corresponds to a time period [ t ] 4 ,t 5 ]Or [ t ] 0 ,t 1 ]Power switch tube SW 1 And SW 2 On, DC voltage V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o At the same time as the power supply, the power switch SW 1 And SW 2 And when the energy release is completed, mode 4 ends.
Further, the gain expression obtainable according to the above-described modal control is:
wherein D is a power switch tube SW 1 And SW 2 The duty ratio of conduction is (0, 1), the turn ratio of the two coupling inductances is n 1 ＝N 2 :N 1 And n 2 ＝N 4 :N 3 。
Drawings
FIG. 1 is a circuit diagram of a high-gain X-source DC boost converter based on a coupled inductor voltage doubling unit;
FIG. 2 is a main waveform diagram of a high-gain X-source DC boost converter based on a coupled inductor voltage doubling unit;
FIG. 3 is an equivalent circuit diagram of each switching mode; wherein (a) is an equivalent circuit diagram of a switching mode 1 of the high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit; (b) An equivalent circuit diagram of a switching mode 2 of the high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit; (c) An equivalent circuit diagram of a switching mode 3 of the high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit; (d) An equivalent circuit diagram of a switching mode 4 of the high-gain X-source direct-current boost converter based on a coupling inductance voltage doubling unit;
FIG. 4 shows the voltage V in =50v, output voltage V o Experimental waveform at=250v.
The reference numerals in the figures illustrate: v (V) in Is a direct current voltage source, SW 1 Is a first power switch tube SW 2 Is a second power switch tube D 1 Is a first voltage-multiplying diode D 2 Is a second voltage-multiplying diode, C 1 C is the first voltage-multiplying capacitor 2 Is the second voltage-multiplying capacitor D o For the output diode, C o Is output capacitance, R is load resistance, N 1 、N 2 To couple two windings of the inductance, N 3 、N 4 Two windings of another coupling inductance, the turns ratio of the two coupling inductances being n respectively 1 ＝N 2 :N 1 And n 2 ＝N 4 :N 3 。
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention provides a high-gain X-source direct current boost converter based on a coupling inductance voltage doubling unit, and belongs to the technical field of power electronic converters. The high-gain X-source direct-current boost converter based on the coupling inductance voltage doubling unit comprises a direct-current voltage source, two coupling inductance voltage doubling units and an X-source structure. Each coupling inductance voltage doubling unit comprises a coupling inductance, a diode and a capacitor, and the X source structure consists of two crossed switches. The high-gain X source direct current boost converter based on the coupling inductance voltage doubling unit greatly improves voltage gain and realizes continuous input current and common ground performance.
Referring to fig. 1, the present invention specifically proposes a high-gain X-source dc boost converter based on a coupled inductive voltage doubling unit, the converter specifically comprising: DC voltage source V in Power switch SW 1 Capacitance C 1 Diode D 1 Coupled inductor winding N 2 Coupled inductor winding N 1 Output diode D o Power switch SW 2 Output capacitance C o Resistor R, capacitor C 2 Diode D 2 Coupled inductor winding N 4 And a coupling inductance winding N 3 ；
DC voltage source V in Positive electrode of (a) and power switch SW 1 Drain electrode of (C) and capacitor (C) 1 Cathode, diode D of (2) 1 Is connected with the positive electrode of the battery; capacitor C 1 Positive pole of (a) and coupling inductance winding N 2 Is connected with the positive electrode of the battery; diode D 1 Is coupled to the cathode of the inductor winding N 1 Is connected with the positive electrode of the battery; coupling inductance winding N 1 Is coupled to the cathode of the inductor winding N 2 Cathode, output diode D o Is provided, and power switch SW 2 Is connected with the drain electrode of the transistor; output diode D o Cathode and output capacitance C of (2) o The positive electrode of the resistor R is connected with one end of the resistor R; output capacitor C o Cathode of resistor R, other end of resistor R, power switch SW 1 Source, capacitance C of (2) 2 Cathode, diode D of (2) 2 Is connected with the positive electrode of the battery; capacitor C 2 Positive pole of (a) and coupled inductance winding N 4 The positive electrode of diode D is connected with 2 Cathode of (a) and coupled inductor winding N 3 Is connected with the positive electrode of the battery; coupling inductance winding N 3 Is coupled to the cathode of the inductor winding N 4 Cathode of (d) DC voltage source V in Cathode of (d) and power switch SW 2 Is connected to the source of the (c).
The working principle and working process of the invention are as follows:
the invention provides a control method of a high-gain X-source direct-current boost converter based on a coupling inductance voltage-multiplying unit gs Simultaneously controlling the power switch SW 1 And SW 2 Is connected with the power supply; the whole control process is divided into 4 switching modes, namely a switching mode 1, a switching mode 2, a switching mode 3 and a switching mode 4. Winding current i of two coupled inductances N1 、i N2 、i N3 、i N4 Diode D 1 Voltage V of (2) D1 Diode D 2 Voltage V of (2) D2 Output diode D o Voltage V of (2) Do Power switch SW 1 、SW 2 Voltage V of (2) SW1 、V SW2 The waveform of (2) is shown in figure 2. The whole control process is specifically described as follows:
Switching mode 3, corresponding to time period [ t ] in FIG. 2 3 ,t 4 ]As shown in fig. 3 (c), the equivalent circuit is shown as a power switch tube SW 1 And SW 2 Remain off, diode D 1 And D 2 Turn-off, DC voltage V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o Supplying power when two coupled inductor winding currents i N1 、i N3 When it is minimized, modality 3 ends.
Switching mode 4, corresponding to time period [ t ] in FIG. 2 4 ,t 5 ]Or [ t ] 0 ,t 1 ]As shown in fig. 3 (d), the equivalent circuit is shown as a power switch tube SW 1 And SW 2 On, DC voltage V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o At the same time as the power supply, the power switch SW 1 And SW 2 And when the energy release is completed, mode 4 ends.
The gain expression obtained according to the above-described mode control is:
wherein D is a power switch tube SW 1 And SW 2 The duty ratio of conduction is (0, 1), the turn ratio of the two coupling inductances is n 1 ＝N 2 :N 1 And n 2 ＝N 4 :N 3 。
The following data through specific experiments illustrate the beneficial effects of the structure of the invention:
as shown in fig. 4, the input voltage V in =50v, output voltage V o ＝250V，n 1 ＝n 2 =1.5, d=0.5, load r=250Ω. FIG. 4 (a) shows an output capacitor voltage of about 250V and a capacitor C 1 Voltage of about 25V and capacitance C 2 The voltage is about 25V. FIG. 4 (b) shows the output diode voltage peak value of about 300V and diode D 1 Peak voltage of about 50V and diode D 2 The voltage peak is about 50V. FIG. 4 (c) shows the input current, the coupled inductor winding N 1 Current and coupled inductor winding N 2 A current. FIG. 4 (d) shows a power switch SW 1 And SW 2 Is 150V. As can be seen from the figure, the input current is continuous and has a higher output gain, and the power switch voltage is lower than the output voltage.
The high-gain X source direct current boost converter and the control method based on the coupling inductance voltage doubling unit provided by the invention are described in detail, and specific examples are applied to the principle and the implementation mode of the invention, and the description of the examples is only used for helping to understand the method and the core idea of the invention; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present invention, the present description should not be construed as limiting the present invention in view of the above.
Claims (3)
1. The high-gain X source direct current boost converter based on the coupled inductance voltage doubling unit is characterized by comprising: DC voltage source V in Power switch SW 1 Capacitance C 1 Diode D 1 Coupled inductor winding N 2 Coupled inductor winding N 1 Output diode D o Power switch SW 2 Output capacitance C o Load resistor R, capacitor C 2 Diode D 2 Coupled inductor winding N 4 And a coupling inductance winding N 3 The method comprises the steps of carrying out a first treatment on the surface of the Wherein, the inductance winding N is coupled 1 And a coupling inductance winding N 2 For the two windings of the first coupling inductance, the coupling inductance winding N 3 And a coupling inductance winding N 4 Two windings that are a second coupling inductance;
DC voltage source V in Positive electrode of (a) and power switch SW 1 Drain electrode of (C) and capacitor (C) 1 Cathode, diode D of (2) 1 Is connected with the positive electrode of the battery; capacitor C 1 Positive pole of (a) and coupling inductance winding N 2 Is connected with the positive electrode of the battery; diode D 1 Is coupled to the cathode of the inductor winding N 1 Is connected with the positive electrode of the battery; coupling inductance winding N 1 Is coupled to the cathode of the inductor winding N 2 Cathode, output diode D o Is provided, and power switch SW 2 Is connected with the drain electrode of the transistor; output diode D o Cathode and output capacitance C of (2) o The positive electrode of the load resistor R is connected with one end of the load resistor R; output capacitor C o Cathode of load resistor R, other end of load resistor R, power switch SW 1 Source, capacitance C of (2) 2 Cathode, diode D of (2) 2 Is connected with the positive electrode of the battery; capacitor C 2 Positive pole of (a) and coupled inductance winding N 4 The positive electrode of diode D is connected with 2 Cathode of (a) and coupled inductor winding N 3 Is connected with the positive electrode of the battery; coupling inductance winding N 3 Is coupled to the cathode of the inductor winding N 4 Cathode of (d) DC voltage source V in Cathode of (d) and power switch SW 2 Is connected to the source of the (c).
2. The control method for a high-gain X-source dc boost converter based on a coupled inductor voltage doubling unit according to claim 1, wherein the high-gain X-source dc boost converter based on the coupled inductor voltage doubling unit controls a signal V gs Simultaneously controlling the power switch SW 1 And SW 2 Is connected with the power supply; finishing the wholeThe control process is divided into 4 switching modes, namely a switching mode 1, a switching mode 2, a switching mode 3 and a switching mode 4;
switching mode 1, corresponding to time period [ t ] 1 ,t 2 ]At this stage, the power switch SW 1 And SW 2 Conduction, DC voltage source V in Through diode D 1 And a power switch SW 2 To the coupled inductor winding N 1 Charging, coupling inductance winding N due to magnetic induction principle 1 And N 2 Through diode D 1 Give electric capacity C 1 Charging; at the same time, DC voltage source V in Through diode D 2 And a power switch SW 1 To the coupled inductor winding N 3 Charging, coupling inductance winding N due to magnetic induction principle 3 And N 4 Through diode D 2 Give electric capacity C 2 Charging; output diode D o Reverse bias, output capacitance C o The load resistor R is independently powered, and the switching mode 1 is ended;
switching mode 2, corresponding to time period [ t ] 2 ,t 3 ]At this stage, the power switch SW 1 And SW 2 Turn-off, DC voltage source V in Respectively give power switch SW 1 And SW 2 Parasitic capacitance and coupled inductance winding N of (a) 1 、N 2 、N 3 、N 4 Charging, and ending the switching mode 2;
switching mode 3, corresponding to time period [ t ] 3 ,t 4 ]Power switch SW 1 And SW 2 Remain off, diode D 1 And D 2 Turn-off, DC voltage source V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o When power is supplied to two coupled inductance windings N 2 、N 4 Is the current i of (2) N2 、i N4 When the switching mode is reduced to the lowest, the switching mode 3 is ended;
switching mode 4, corresponding to time period [ t ] 4 ,t 5 ]Or [ t ] 0 ,t 1 ]Power switch SW 1 And SW 2 On, DC voltage source V in Capacitance C 1 And C 2 Two coupled inductor windings N 2 And N 4 Through the output diode D o For load resistor R and output capacitor C o At the same time as the power supply, the power switch SW 1 And SW 2 And when the energy release is completed, the switching mode 4 is ended.
3. The method of claim 2, wherein the gain expression obtainable according to the mode control is:
wherein D is a power switch SW 1 And SW 2 The duty ratio of conduction is (0, 1), the turn ratio of the two coupling inductances is n 1 ＝N 2 :N 1 And n 2 ＝N 4 :N 3 。
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| CN114977790A (en) * | 2022-07-12 | 2022-08-30 | 安徽工业大学 | Two-phase interleaved Boost-Sepic type high-gain converter based on coupling inductor and control method |
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| CN104702105A (en) * | 2015-04-01 | 2015-06-10 | 哈尔滨工业大学 | Boost converter for similar active switch inductance network |
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