Valley filling type power factor compensation rectifying circuit
Through the valley-filled power factor compensation rectification circuit, alternating charging is achieved using the specific connection between diodes and capacitors, which solves the problems of poor current continuity and high cost of active Boost PFC in traditional rectifier bridge devices, and achieves a significant increase in power factor.
Patent Information
- Application Number
- CN202510588315.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-08
- Publication Date
- 2025-07-08
AI Technical Summary
The traditional single-phase rectifier bridge device has poor current continuity, difficulty in improving the power factor, and active Boost PFC is costly, complex in structure, and large in area.
The valley-filled power factor compensation rectification circuit is used to realize alternating charging through specific connected diodes and capacitor groups to avoid the problem of low power factor caused by filter capacitors.
While keeping the structure simple and low cost, it significantly improves the power factor and avoids the need for complex control circuits.
Smart Images
Figure CN120281180A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of power electronics technology, and particularly relates to a valley-fill type power factor compensation rectifier circuit. Background Art
[0002] During the operation of power electronic devices, the power factor is an important indicator to measure the efficiency of electrical energy utilization. However, there are some problems in the practical application of traditional single-phase rectifier bridge devices.
[0003] Traditional single-phase rectifier bridge devices rely on capacitor energy storage and only achieve energy conversion in the voltage peak region. Their current waveforms only conduct near the peak of the AC voltage, and the current action time is only 2 - 3 ms, resulting in poor current continuity and difficulty in improving the power factor. Currently, the mainstream active Boost PFC accounts for more than 98% in the current market. However, although the active Boost PFC can improve the power factor, it uses complex inductors, capacitors, and control circuits, having the disadvantages of high cost, complex structure, and large board area, which not only increases the system complexity but also raises the manufacturing cost and space requirements.
[0004] Therefore, there is an urgent need to design a valley-fill type power factor compensation rectifier circuit that can improve the power factor. Summary of the Invention
[0005] The purpose of the present invention is to overcome the above problems and provide a valley-fill type power factor compensation rectifier circuit.
[0006] To achieve the above purpose, the present invention adopts the following technical solutions:
[0007] A valley-fill type power factor compensation rectifier circuit includes an input terminal, an output terminal, a diode group, and a capacitor group; the diode group includes diode D1, diode D2, diode D3, diode D4, diode D5, diode D6, diode D7, and diode D8; both ends of diode D1 are respectively connected to the anodes of diode D4 and diode D5; both ends of diode D2 are respectively connected to the cathodes of diode D7 and diode D8; the cathode of diode D3 is connected to the cathode of diode D4; the anode of diode D4 is connected to the cathode of diode D1; the anode of diode D6 is respectively connected to the anodes of diode D7 and diode D8.
[0008] Further, the input terminals include terminal L, terminal N, terminal A, and terminal B; terminal L is respectively connected to the anode of diode D3 and the cathode of diode D6; terminal N is respectively connected to the anodes of diodes D1 and D5 and the cathodes of diodes D2 and D8; terminal A is respectively connected to the cathode of diode D1 and the anode of diode D4; terminal B is respectively connected to the anode of diode D2 and the cathode of diode D7.
[0009] Further, the capacitor bank includes capacitors C1, C2, and C3. Both ends of capacitor C1 are respectively connected to the anodes of diodes D3 and D4; both ends of capacitor C2 are respectively connected to the cathodes of diodes D7 and D8; the positive electrode of capacitor C3 is connected to the cathode of diode D5, and the negative electrode is connected to the anode of diode D8.
[0010] Further, the output terminals include terminal H and terminal M; terminal H is respectively connected to the positive electrode of capacitor C3 and the cathode of diode D5; terminal M is connected to the negative electrode of capacitor C3 and the anode of diode D8.
[0011] Further, the anodes of diodes D3, D4, D5, D6, D7, and D8 all face downward.
[0012] The advantages of the present invention are as follows:
[0013] Through the specific connection of diodes and capacitors, the present invention enables capacitors C1 and C2 to alternately charge in the circuit and discharge energy to capacitor C3, avoiding the problem of low power factor caused by filter capacitor C3 and achieving a significant increase in the power factor value; without a complex control circuit, it realizes effective improvement of the power factor while maintaining a simple structure and low cost. Description of the Drawings
[0014] Figure 1 It is a circuit connection diagram of a valley filling type power factor compensation rectifier circuit in Embodiment 1. Detailed Embodiments
[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.
[0016] The present invention will be described in detail and specifically through specific embodiments to better understand the present invention. However, the following embodiments do not limit the protection scope of the present invention.
[0017] Embodiment 1
[0018] As Figure 1 shown, a valley-fill type power factor compensation rectifier circuit includes an input terminal, an output terminal, a diode group, and a capacitor group; the diode group includes diodes D1, D2, D3, D4, D5, D6, D7, and D8; both ends of the diode D1 are respectively connected to the anodes of the diodes D4 and D5; both ends of the diode D2 are respectively connected to the cathodes of the diodes D7 and D8; the cathode of the diode D3 is connected to the cathode of the diode D4; the anode of the diode D4 is connected to the cathode of the diode D1; the anode of the diode D6 is respectively connected to the anodes of the diodes D7 and D8.
[0019] Further, the input terminal includes terminals L, N, A, and B; the terminal L is respectively connected to the anode of the diode D3 and the cathode of the diode D6; the terminal N is respectively connected to the anodes of the diodes D1 and D5 and the cathodes of the diodes D2 and D8; the terminal A is respectively connected to the cathode of the diode D1 and the anode of the diode D4; the terminal B is respectively connected to the anode of the diode D2 and the cathode of the diode D7.
[0020] Further, the capacitor group includes capacitors C1, C2, and C3. Both ends of the capacitor C1 are respectively connected to the anodes of the diodes D3 and D4; both ends of the capacitor C2 are respectively connected to the cathodes of the diodes D7 and D8; the positive electrode of the capacitor C3 is connected to the cathode of the diode D5, and the negative electrode is connected to the anode of the diode D8.
[0021] Further, the output terminal includes terminals H and M; the terminal H is respectively connected to the positive electrode of the capacitor C3 and the cathode of the diode D5; the terminal M is connected to the negative electrode of the capacitor C3 and the anode of the diode D8.
[0022] Further, the diodes D3, D4, D5, D6, D7, and D8 all have their positive electrodes facing down.
[0023] The sinusoidal alternating current is connected from terminals L and N. When terminal L is positive and terminal N is negative, the capacitor D3 at the positive end and the diode D8 at the negative end conduct to charge the capacitor C3. At this time, the capacitor C1 and the diode D4 are in series and in parallel with the diode D3, so the capacitor C3 cannot be charged at this time. From the negative end, the diode D2 conducts to charge the capacitor C2, and the charging value reaches U LN 。
[0024] When terminal L is negative and terminal N is positive, the diode D5 at the positive end and the diode D6 at the negative end conduct to charge the capacitor C3. At the same time, the diode D1 conducts to charge the capacitor C1, and the charging value reaches U NL 。 At this time, the initial state of the capacitor C2 is positive on the left and negative on the right. At this time, the sinusoidal alternating current is negative at terminal L and positive at terminal N. It can be seen that when the diode D2 conducts, the diode D1 charges the capacitor C1, and at the same time, the energy of the capacitor C2 is released into the capacitor C3.
[0025] When terminal N is negative and terminal L is positive, the diode D8 at the positive end and the diode D3 at the negative end conduct and charge the capacitor C3. At the same time, the diode D2 conducts to charge the capacitor C1, and the charging value reaches U LN , At this time, the initial state of the capacitor C2 is positive on the left and negative on the right. At this time, the sinusoidal alternating current is negative at terminal L and positive at terminal N. It can be seen that when the diode D1 conducts, the diode D2 charges the capacitor C2, and at the same time, the energy of the capacitor C1 is released into the capacitor C3.
[0026] Thus, this circuit can greatly improve the power factor value.
[0027] The specific embodiments of the present invention have been described in detail above, but they are only examples. The present invention is not equivalent to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.
Claims
1. A valley filling type power factor compensation rectifier circuit, characterized in that: It includes an input terminal, an output terminal, a diode group and a capacitor group; the diode group includes diodes D1, D2, D3, D4, D5, D6, D7 and D8; both ends of the diode D1 are respectively connected to the anodes of the diodes D4 and D5; both ends of the diode D2 are respectively connected to the cathodes of the diodes D7 and D8; the cathode of the diode D3 is connected to the cathode of the diode D4; the anode of the diode D4 is connected to the cathode of the diode D1; the anode of the diode D6 is respectively connected to the anodes of the diodes D7 and D8.
2. The valley filling type power factor compensation rectifier circuit according to claim 1, wherein: The input terminal includes terminals L, N, A and B; the terminal L is respectively connected to the anode of the diode D3 and the cathode of the diode D6; the terminal N is respectively connected to the anodes of the diodes D1 and D5 and the cathodes of the diodes D2 and D8; the terminal A is respectively connected to the cathode of the diode D1 and the anode of the diode D4; the terminal B is respectively connected to the anode of the diode D2 and the cathode of the diode D7.
3. The valley filling type power factor compensation rectification circuit according to claim 2, wherein: The capacitor group includes capacitors C1, C2 and C3; both ends of the capacitor C1 are respectively connected to the anodes of the diodes D3 and D4; both ends of the capacitor C2 are respectively connected to the cathodes of the diodes D7 and D8; the positive electrode of the capacitor C3 is connected to the cathode of the diode D5, and the negative electrode is connected to the anode of the diode D8.
4. The valley filling type power factor compensation rectifier circuit according to claim 2, characterized in that: The output terminal includes terminals H and M; the terminal H is respectively connected to the positive electrode of the capacitor C3 and the cathode of the diode D5; the terminal M is connected to the negative electrode of the capacitor C3 and the anode of the diode D8.
5. A valley filling type power factor compensation rectification circuit according to claim 2, characterized in that: The diodes D3, D4, D5, D6, D7 and D8 all have their positive electrodes facing down.