Direct-current power supply circuit and lamp

Abstract

The utility model discloses a direct current power supply circuit and a lamp, and relates to the technical field of circuits and lamps, the direct current power supply circuit comprises a combined type electrolytic capacitor which is connected in parallel in a direct current circuit obtained by rectification of a rectification circuit, the combined type electrolytic capacitor is formed by connecting two electrolytic capacitors in series, one electrolytic capacitor is a large-capacitance low-voltage electrolytic capacitor, the other electrolytic capacitor is a small-capacitance high-voltage electrolytic capacitor, and the negative electrode of the large-capacitance low-voltage electrolytic capacitor is connected with the positive electrode of the small-capacitance high-voltage electrolytic capacitor. The two electrolytic capacitors are small in size, small in size after being combined, and small in occupied space.

Description

DC power supply circuits and lighting fixtures Technical Field

[0001] This utility model relates to the field of circuit and lighting technology, and in particular to a DC power supply circuit and a lighting fixture. Background Technology

[0002] In existing technologies, in power supply circuits that rectify 220V AC power to obtain 300V DC power, an electrolytic capacitor is connected in parallel for filtering to prevent high current surges and protect the load. This electrolytic capacitor must have a sufficiently large capacitance to effectively protect the load from surges while also functioning normally in a 300V DC circuit. When both conditions are met, the electrolytic capacitor used is relatively large, occupying a significant amount of space. This has several disadvantages for lighting fixtures such as LED lights. Firstly, because LED lights generally pursue a thin and compact design, the presence of a large electrolytic capacitor severely restricts their industrial design, making it difficult to achieve a slimmer shape and meet modern consumers' aesthetic demands for home décor. Secondly, a large electrolytic capacitor will encroach on the limited internal space of the LED light, affecting the layout of other components, increasing wiring difficulty, potentially leading to circuit interference problems, and increasing the complexity and cost of production and assembly. In addition, the use of large-volume electrolytic capacitors makes LED lights more susceptible to damage from collisions and squeezing during transportation and installation, reducing the reliability and lifespan of the products. Summary of the Invention

[0003] One of the purposes of this invention is to provide a DC power supply circuit that can solve the problem of large size and space-consuming electrolytic capacitors in parallel DC power supply circuits.

[0004] To solve the above problems, the technical solution adopted by this utility model is as follows: a combined electrolytic capacitor is included in parallel in the DC circuit rectified by the rectifier circuit. The combined electrolytic capacitor is composed of two electrolytic capacitors connected in series. Of the two electrolytic capacitors, one is a large-capacity low-voltage electrolytic capacitor and the other is a small-capacity high-voltage electrolytic capacitor. The negative terminal of the large-capacity low-voltage electrolytic capacitor is connected to the positive terminal of the small-capacity high-voltage electrolytic capacitor.

[0005] A more specific technical solution than the above-mentioned technical solution is that the voltage in the DC power supply circuit obtained by rectifying the combined electrolytic capacitor connected in parallel with the rectifier circuit is lower than 400V.

[0006] In some possible implementations, a resistor is connected in parallel in the DC circuit following the rectifier circuit.

[0007] The second objective of this utility model is to provide a lamp that can solve the problem that current lamps have large electrolytic capacitors connected in parallel to the power supply circuit, which occupy space in the lamp design.

[0008] To solve the above problems, the technical solution adopted by this utility model is: this lamp uses a DC power supply circuit including any one of the above-mentioned features.

[0009] By adopting the above technical solution, this utility model has the following beneficial effects compared with the prior art:

[0010] Because a combined electrolytic capacitor consists of two electrolytic capacitors connected in series, one is a large-capacity, low-voltage electrolytic capacitor, and the other is a small-capacity, high-voltage electrolytic capacitor. The negative terminal of the large-capacity, low-voltage electrolytic capacitor is connected to the positive terminal of the small-capacity, high-voltage electrolytic capacitor. The large-capacity, low-voltage electrolytic capacitor can absorb a large current instantaneously, protecting the load from damage caused by a sudden surge of high current. The small-capacity, high-voltage electrolytic capacitor ensures that the combined electrolytic capacitor can operate normally under high voltage. The combined electrolytic capacitor effectively performs the functions of filtering and shock protection for the load. Both individual electrolytic capacitors are small in size, and the combined size is also small, occupying minimal space. Attached Figure Description

[0011] Figure 1 is a schematic diagram of the DC power supply circuit of this utility model.

[0012] Figure 2 is a circuit diagram of the lamp of this utility model. Detailed Implementation

[0013] To facilitate a clearer understanding of the aforementioned objectives, features, and advantages of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model; however, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0014] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0015] As shown in Figure 1, the DC power supply circuit includes a combined electrolytic capacitor connected in parallel in the DC power circuit rectified by the rectifier bridge D. This combined electrolytic capacitor consists of two electrolytic capacitors, C1 and C2, connected in series. C1 is a large-capacity, low-voltage electrolytic capacitor, and C2 is a small-capacity, high-voltage electrolytic capacitor. The negative terminal of the large-capacity, low-voltage electrolytic capacitor C1 is connected to the positive terminal of the small-capacity, high-voltage electrolytic capacitor C2. The combined electrolytic capacitor is connected in parallel in the rectifier circuit, resulting in a DC power supply circuit with a voltage below 400V. A resistor R is connected in parallel in the DC power circuit after the rectifier circuit. The DC output terminals E and F can be connected to DC power loads, such as mobile phone chargers or lamps.

[0016] As shown in Figure 2, in the circuit implementation scheme of the lamp, a combined electrolytic capacitor is connected in parallel in the DC rectification circuit of the rectifier bridge D. This combined electrolytic capacitor consists of two electrolytic capacitors, C1 and C2, connected in series. The positive terminal of electrolytic capacitor C1 is connected to pin 3 of the rectifier bridge D, the negative terminal of electrolytic capacitor C1 is connected to the positive terminal of electrolytic capacitor C2, and the negative terminal of electrolytic capacitor C2 is connected to pin 4 of the rectifier bridge D. The load R... L It is connected in series with the DC output terminals E and F. C1 is a 220μF / 16V electrolytic capacitor, C2 is a 4.7μF / 400V electrolytic capacitor, and the load R... L This is a lamp made up of 100 0.2W LEDs connected in series, with R being the discharge resistor. A 220V AC power supply is input to terminals A and B of the power source. The rectifier bridge D outputs a 300V pulsating DC power, with pin 3 positive and pin 4 negative. Electrolytic capacitor C1 has a withstand voltage of only 16V; if used alone, it would be instantly damaged under 300V DC. However, C2, connected in series with C1, is a 400V-capable electrolytic capacitor and can operate normally under 300V DC. The combined electrolytic capacitor formed by C1 and C2 in series can operate normally under 300V DC. The 300V pulsating DC power supply contains an AC component, which must be filtered out. Since AC can pass through the electrolytic capacitors without obstruction, the AC can be filtered out. The AC path is: power source positive terminal – C1 positive terminal – C1 negative terminal – C2 positive terminal – C2 negative terminal – power source negative terminal; the AC is filtered out. Direct current (DC) cannot pass through an electrolytic capacitor, but it can charge it. When 300V DC charges electrolytic capacitor C1, because C1 has a large capacitance, it can absorb a large amount of DC current instantaneously; only a small portion of the DC current flows through the load R. L As the electrolytic capacitor C1 is fully charged, current flows through the load R L The current gradually reaches its maximum value, thus the load R... LIt will not be damaged by a sudden surge of high current. The circuit in this implementation scheme can perform the tasks of filtering and protecting the load.

[0017] A large-capacitance, low-voltage electrolytic capacitor C1 and a small-capacitance, high-voltage electrolytic capacitor C2 are connected in series to form a combined electrolytic capacitor that can operate normally under high voltage. The large-capacitance, low-voltage electrolytic capacitor can absorb a large current instantaneously, protecting the load from damage caused by a sudden surge of large current. The small-capacitance, high-voltage electrolytic capacitor ensures that the combined electrolytic capacitor can operate normally under high voltage. The combined electrolytic capacitor effectively performs the functions of filtering and shock protection for the load. Both individual electrolytic capacitors are small in size, and the combined size is also small, occupying minimal space.

Claims

1. A DC power supply circuit, characterized in that: It includes a combined electrolytic capacitor connected in parallel in the DC circuit obtained by the rectifier circuit. The combined electrolytic capacitor is composed of two electrolytic capacitors connected in series. One of the two electrolytic capacitors is a large-capacity, low-voltage electrolytic capacitor, and the other is a small-capacity, high-voltage electrolytic capacitor. The negative terminal of the large-capacity, low-voltage electrolytic capacitor is connected to the positive terminal of the small-capacity, high-voltage electrolytic capacitor.

2. The DC power supply circuit according to claim 1, characterized in that: The combined electrolytic capacitors are connected in parallel to the rectifier circuit to rectify the DC power supply circuit to obtain a voltage below 400V.

3. The DC power supply circuit according to claim 1 or 2, characterized in that: A resistor is connected in parallel in the DC circuit following the rectifier circuit.

4. A lamp, characterized in that: Includes the DC power supply circuit as described in any one of claims 1-3.

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