A current correction topology circuit based on bidirectional boost lossless conversion

Abstract

A current correction topology circuit based on bidirectional boost-type lossless conversion, comprising: a rectifier circuit for converting the AC power of an AC power supply into DC power; the rectifier circuit is connected to the AC power supply; a boost circuit for increasing the AC voltage of the AC power supply; the boost circuit is respectively connected to the AC power supply and the rectifier circuit; a lossless conversion circuit for absorbing the peak voltage generated in the boost circuit and outputting a bidirectional DC voltage; the lossless conversion circuit is respectively connected to the boost circuit and an output port. The present application provides a current correction topology circuit based on bidirectional boost-type lossless conversion, which corrects the sinusoidal voltage by improving the rectifier circuit and adjusting the position of the boost inductor in the traditional current correction topology circuit, and can output a bidirectional bus voltage using only one inductor, thereby saving the number of inductors and reducing the weight of the product.

Description

Technical Field

[0001] The invention belongs to the technical field of current correction topology circuits, and in particular relates to a current correction topology circuit based on bidirectional boost type lossless conversion. Background Art

[0002] With the rapid development of aviation technology and avionics, there are more and more airborne electrical equipment, and the requirements for the power quality of electrical equipment are becoming more and more stringent. AC electrical equipment causes the power grid to contain seriously distorted non-positive current due to current harmonic pollution. Such harmonic current has a harmful effect on the power grid and even the entire aircraft.

[0003] Figure 1 This is a traditional bidirectional current correction topology circuit. In this circuit, in order to solve the traditional current correction topology, the AC input needs to be doubled and rectified, and then two current correction circuits are applied for positive and negative control to obtain two outputs. However, this traditional bidirectional current correction topology circuit is complex to operate, has many components, and has a cumbersome control method. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a current correction topology circuit based on bidirectional boost type lossless conversion, comprising:

[0005] A rectifier circuit, used for converting AC power of an AC power source into DC power; the rectifier circuit is connected to the AC power source;

[0006] A boost circuit, used to increase the AC voltage of the AC power supply; the boost circuit is connected to the AC power supply and the rectifier circuit respectively;

[0007] The lossless conversion circuit is used to absorb the peak voltage generated in the boost circuit and output a bidirectional DC voltage; the lossless conversion circuit is connected to the boost circuit and the output port respectively.

[0008] Preferably, the rectifier circuit includes: a diode D1, a diode D2, a transistor Q1 and a transistor Q2, wherein the anode of the diode D1 and the cathode of the diode D2 are connected to the boost circuit, the cathode of the diode D1 is connected to the collector of the transistor Q2, the anode of the diode D2 is connected to the emitter of the transistor Q1, the collector of the transistor Q1 and the emitter of the transistor Q2 are both connected to the AC-N signal terminal in the AC power supply, the base of the transistor Q1 is connected to the G1 signal terminal, and the base of the transistor Q2 is connected to the G2 signal terminal.

[0009] Preferably, the boost circuit comprises: an inductor L1, a diode D3, a diode D4 and a transistor Q3, wherein the first end of the inductor L1 is connected to the AC-L signal terminal in the AC power supply and the second end is respectively connected to the anode of the diode D1, the cathode of the diode D2, the anode of the diode D3 and the cathode of the diode D4 in the rectifier circuit, the cathode of the diode D3 and the anode of the diode D4 are both connected to the lossless conversion circuit, the collector of the transistor Q3 is connected to the cathode of the diode D1, the emitter of the transistor Q3 is connected to the anode of the diode D2, and the base of the transistor Q3 is connected to the G3 signal terminal.

[0010] Preferably, the boost circuit further includes: a diode D9, the emitter of the transistor Q3 is connected to the anode of the diode D9, and the collector of the transistor Q3 is connected to the cathode of the diode D9.

[0011] Preferably, the diode D9 is a silicon carbide diode.

[0012] Preferably, the boost circuit further includes: a capacitor C5, the emitter of the transistor Q3 is connected to a first end of the capacitor C5, and the collector of the transistor Q3 is connected to a second end of the capacitor C5.

[0013] Preferably, the capacitor C5 is a ceramic capacitor.

[0014] Preferably, the lossless conversion circuit comprises: an inductor L2, an inductor L3, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4, wherein a first end of the inductor L2 is connected to a cathode of the diode D3 in the boost circuit and a first end of the capacitor C1 and a second end is connected to a positive DC signal end in the output port, a second end of the capacitor C1 is respectively connected to an anode of the diode D5 and a cathode of the diode D6, a cathode of the diode D5 and a first end of the capacitor C3 are connected to the positive DC signal end in the output port, The positive DC signal terminal, the anode of the diode D6 and the second end of the capacitor C3 are both grounded, the first end of the capacitor C2 and the inductor L3 are connected to the anode of the diode D4 in the boost circuit, the second end of the inductor L3 is connected to the negative DC signal terminal in the output port, the second end of the capacitor C2 is respectively connected to the anode of the diode D7 and the cathode of the diode D8, the anode of the diode D8 is connected to the negative DC signal terminal, the cathode of the diode D7 is grounded, the first end of the capacitor C4 is grounded and the second end is connected to the negative DC signal terminal.

[0015] The current correction topology circuit based on bidirectional boost lossless conversion provided by the present application has the following effective effects:

[0016] (1) By improving the rectifier circuit and adjusting the position of the boost inductor in the traditional current correction topology circuit, the sinusoidal voltage can be corrected, and the bidirectional bus voltage can be output with only one inductor, saving the number of inductors and reducing the weight of the product;

[0017] (2) By controlling the turn-on time of the corresponding transistor in the improved rectifier circuit, the conduction loss of the diode in the traditional rectifier current circuit can be reduced, thereby improving the efficiency of the product;

[0018] (3) It can absorb the peak voltage generated by the rectifier diode, facilitate the selection of diode parameters, and improve the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a connection diagram of a conventional bidirectional current correction topology circuit provided by the prior art;

[0021] Figure 2 The present invention provides a connection diagram of a current correction topology circuit based on bidirectional boost type lossless conversion. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0023] like Figure 2 In an embodiment of the present application, the present invention provides a current correction topology circuit based on a bidirectional boost type lossless conversion, comprising:

[0024] A rectifier circuit, used for converting AC power of an AC power source into DC power; the rectifier circuit is connected to the AC power source;

[0025] A boost circuit, used to increase the AC voltage of the AC power supply; the boost circuit is connected to the AC power supply and the rectifier circuit respectively;

[0026] The lossless conversion circuit is used to absorb the peak voltage generated in the boost circuit and output a bidirectional DC voltage; the lossless conversion circuit is connected to the boost circuit and the output port respectively.

[0027] like Figure 2 In the embodiment of the present application, the present invention provides a current correction topology circuit based on bidirectional boost lossless conversion and Figure 1 Compared with the traditional circuit, the unidirectional switch is replaced with a bidirectional switch, the boost inductor is moved between the improved rectifier circuit and the AC power input, and a power diode is added. The output voltage is adjusted bidirectionally by using the boost inductor and the improved rectifier circuit, and then the on and off of the current correction switch tube is controlled to finally obtain a bidirectional DC voltage with current correction. Since the high-voltage DC output by the boost circuit will generate a very high peak voltage during the rectification process, it will reduce the reliability of the diode and the efficiency of the product, and the use of the traditional RCD buffer circuit will cause some losses, so a lossless conversion circuit is designed at the bidirectional output end, which can store the energy of the peak voltage in the capacitor and inductor, and release it to the output end during the shutdown of the current correction switch tube, so as to achieve the effect of lossless conversion.

[0028] like Figure 2 In an embodiment of the present application, the rectifier circuit includes: a diode D1, a diode D2, a transistor Q1 and a transistor Q2, wherein the anode of the diode D1 and the cathode of the diode D2 are connected to the boost circuit, the cathode of the diode D1 is connected to the collector of the transistor Q2, the anode of the diode D2 is connected to the emitter of the transistor Q1, the collector of the transistor Q1 and the emitter of the transistor Q2 are both connected to the AC-N signal terminal in the AC power supply, the base of the transistor Q1 is connected to the G1 signal terminal, and the base of the transistor Q2 is connected to the G2 signal terminal.

[0029] like Figure 2 In an embodiment of the present application, the boost circuit includes: an inductor L1, a diode D3, a diode D4 and a transistor Q3, wherein the first end of the inductor L1 is connected to the AC-L signal terminal in the AC power supply and the second end is respectively connected to the anode of the diode D1, the cathode of the diode D2, the anode of the diode D3 and the cathode of the diode D4 in the rectifier circuit, the cathode of the diode D3 and the anode of the diode D4 are both connected to the lossless conversion circuit, the collector of the transistor Q3 is connected to the cathode of the diode D1, the emitter of the transistor Q3 is connected to the anode of the diode D2, and the base of the transistor Q3 is connected to the G3 signal terminal.

[0030] like Figure 2In the embodiment of the present application, the boost circuit further includes: a diode D9, the emitter of the transistor Q3 is connected to the anode of the diode D9, and the collector of the transistor Q3 is connected to the cathode of the diode D9.

[0031] In the embodiment of the present application, the diode D9 is a silicon carbide diode. The silicon carbide diode has an ultra-fast switching speed, and the switching characteristics are not affected by the junction temperature; it has ultra-low switching loss, and the response recovery time is zero; it is a dedicated boost diode for high-efficiency boost circuits, and is also suitable for current photovoltaic grid-connected, as well as some power supplies that pursue high efficiency.

[0032] like Figure 2 In the embodiment of the present application, the boost circuit further includes: a capacitor C5, the emitter of the transistor Q3 is connected to the first end of the capacitor C5, and the collector of the transistor Q3 is connected to the second end of the capacitor C5.

[0033] In the embodiment of the present application, the capacitor C5 is a ceramic capacitor. The ceramic capacitor has a small positive capacitance temperature coefficient and is used in a high-stability oscillation circuit to eliminate high-frequency interference.

[0034] like Figure 2 In the embodiment of the present application, the lossless conversion circuit includes: an inductor L2, an inductor L3, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4, wherein the first end of the inductor L2 is connected to the cathode of the diode D3 in the boost circuit and the first end of the capacitor C1 and the second end is connected to the positive DC signal end in the output port, the second end of the capacitor C1 is respectively connected to the anode of the diode D5 and the cathode of the diode D6, the cathode of the diode D5 and the first end of the capacitor C3 The positive DC signal terminal is connected, the anode of the diode D6 and the second end of the capacitor C3 are both grounded, the first end of the capacitor C2 and the inductor L3 are connected to the anode of the diode D4 in the boost circuit, the second end of the inductor L3 is connected to the negative DC signal terminal in the output port, the second end of the capacitor C2 is respectively connected to the anode of the diode D7 and the cathode of the diode D8, the anode of the diode D8 is connected to the negative DC signal terminal, the cathode of the diode D7 is grounded, the first end of the capacitor C4 is grounded and the second end is connected to the negative DC signal terminal.

[0035] The working principle of a current correction topology circuit based on bidirectional boost lossless conversion provided in this application is as follows:

[0036] When the input AC power of the AC power supply is in the positive half cycle of the sine wave, the transistor Q1 (rectifier switch tube) is turned on in the sine half wave state, the transistor Q3 (correction switch tube) is in the on state of a switching cycle T under PWM control, and the diode D4 is reversely cut off. in A loop is formed by inductor L1 (boost inductor), diode D1, transistor Q3 (correction switch tube), and transistor Q1 (rectifier switch tube). At this time, the input voltage is added to the inductor L1 (boost inductor), and the inductor L1 (boost inductor) stores energy. The inductor current i L Linearly increasing, we can get U in =Ldi L / dt, where L is the inductance of the inductor L1 (boost inductor). When the transistor Q3 (correction switch) takes D as the duty cycle, the increase in the current on the boost inductor L1 within a switching cycle T is Δi L+ =U in DT / L. With the continuous opening of transistor Q3 (correction switch), the lossless conversion circuit charges capacitor C2 through capacitor C1 and diode D5. Capacitor C2 increases from zero and reaches a peak value after half a cycle of resonance between inductor L3 and capacitor C1. During this process, diode D5 is in the on state, and the voltage across diode D6 is the output voltage U 0+ After half a cycle of resonance, diode D5 is turned off due to reverse voltage, capacitor C1 starts to release part of the stored energy to the output, and the voltage on diode D6 becomes zero.

[0037] When the transistor Q3 (correction switch tube) ends the on state and enters the off state, the diode D4 is turned on, and the AC input U in A loop is formed by inductor L1 (boost inductor), diode D4 and capacitor C3. At this time, the inductor releases energy and charges capacitor C3 together with the AC input. The voltage on capacitor C3 is U 0+ That is the positive output voltage, the reduction in current on the boost inductor is Δi L- =(U 0+ -U in )(1-D)T / L. Within one T, the voltage transformation on the inductor L1 (boost inductor) should be 0, that is, the inductor satisfies the volt-second integral balance, so Δi L+ =Δi L- , that is U in DT / L=(U 0+ -U in )(1-D)T / L, derive U 0+ / U in=1(1-D), and the boost correction work of the positive half cycle can be completed by adjusting the duty cycle D. When the transistor Q3 (correction switch) is turned off, the current of the diode D4 in the lossless conversion circuit begins to decrease, the diode D6 begins to conduct, and the energy in the capacitor C1 is released to the output through L2. When the diode D4 is completely turned off, the capacitor C1 begins to provide all the output energy.

[0038] When the input AC is in the negative half cycle of the sine wave, the circuit works in the same way as the positive half cycle. in The circuit is formed by inductor L1 (boost inductor), diode D2, transistor Q2 (rectifier switch tube), and transistor Q2 (correction switch tube). The positive and negative half-waves of the input AC work symmetrically, and the required bidirectional DC bus voltage can be obtained on the output capacitors C3 and C4, and output through the output port.

[0039] The current correction topology circuit based on bidirectional boost lossless conversion provided by the present application has the following effective effects:

[0040] (1) By improving the rectifier circuit and adjusting the position of the boost inductor in the traditional current correction topology circuit, the sinusoidal voltage can be corrected, and the bidirectional bus voltage can be output with only one inductor, saving the number of inductors and reducing the weight of the product;

[0041] (2) By controlling the turn-on time of the corresponding transistor in the improved rectifier circuit, the conduction loss of the diode in the traditional rectifier current circuit can be reduced, thereby improving the efficiency of the product;

[0042] (3) It can absorb the peak voltage generated by the rectifier diode, facilitate the selection of diode parameters, and improve the reliability of the system.

[0043] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A current correction topology circuit based on bidirectional boost lossless conversion, characterized in that: include: A rectifier circuit, used for converting AC power of an AC power supply into DC power; the rectifier circuit is connected to the AC power supply; the rectifier circuit comprises a diode D1, a diode D2, a transistor Q1 and a transistor Q2, wherein the anode of the diode D1 and the cathode of the diode D2 are connected to a boost circuit, the cathode of the diode D1 is connected to the collector of the transistor Q2, the anode of the diode D2 is connected to the emitter of the transistor Q1, the collector of the transistor Q1 and the emitter of the transistor Q2 are both connected to an AC-N signal terminal in the AC power supply, the base of the transistor Q1 is connected to a G1 signal terminal, and the base of the transistor Q2 is connected to a G2 signal terminal; A boost circuit, used for boosting the AC voltage of the AC power supply; the boost circuit is connected to the AC power supply and the rectifier circuit respectively; the boost circuit comprises an inductor L1, a diode D3, a diode D4 and a transistor Q3, wherein a first end of the inductor L1 is connected to an AC-L signal terminal in the AC power supply and a second end is respectively connected to an anode of the diode D1, a cathode of the diode D2, an anode of the diode D3 and a cathode of the diode D4 in the rectifier circuit, the cathode of the diode D3 and the anode of the diode D4 are both connected to a lossless conversion circuit, a collector of the transistor Q3 is connected to a cathode of the diode D1, an emitter of the transistor Q3 is connected to an anode of the diode D2, and a base of the transistor Q3 is connected to a G3 signal terminal; A lossless conversion circuit is used to absorb the peak voltage generated in the boost circuit and output a bidirectional DC voltage; the lossless conversion circuit is connected to the boost circuit and the output port respectively; the lossless conversion circuit includes an inductor L2, an inductor L3, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C1, a capacitor C2, a capacitor C3 and a capacitor C4, wherein the first end of the inductor L2 is connected to the cathode of the diode D3 in the boost circuit and the first end of the capacitor C1 and the second end is connected to the positive DC signal end in the output port, and the second end of the capacitor C1 is connected to the anode of the diode D5 and the anode of the diode D6 respectively. The cathode of the diode D5 and the first end of the capacitor C3 are connected to the positive DC signal terminal, the anode of the diode D6 and the second end of the capacitor C3 are both grounded, the capacitor C2 and the first end of the inductor L3 are connected to the anode of the diode D4 in the boost circuit, the second end of the inductor L3 is connected to the negative DC signal terminal in the output port, the second end of the capacitor C2 is respectively connected to the anode of the diode D7 and the cathode of the diode D8, the anode of the diode D8 is connected to the negative DC signal terminal, the cathode of the diode D7 is grounded, the first end of the capacitor C4 is grounded and the second end is connected to the negative DC signal terminal.

2. The current correction topology circuit based on bidirectional boost lossless conversion according to claim 1 is characterized in that: The boost circuit further includes: a diode D9, the emitter of the transistor Q3 is connected to the anode of the diode D9, and the collector of the transistor Q3 is connected to the cathode of the diode D9.

3. The current correction topology circuit based on bidirectional boost lossless conversion according to claim 2 is characterized in that: The diode D9 is a silicon carbide diode.

4. The current correction topology circuit based on bidirectional boost lossless conversion according to claim 1 is characterized in that: The boost circuit further includes: a capacitor C5, the emitter of the transistor Q3 is connected to a first end of the capacitor C5, and the collector of the transistor Q3 is connected to a second end of the capacitor C5.

5. The current correction topology circuit based on bidirectional boost lossless conversion according to claim 4 is characterized in that: The capacitor C5 is a ceramic capacitor.

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