阅读说明：本技术 一种用于切相调光电源的维持电流电路 (A hold current circuit for cutting looks light modulation power ) 是由 吴印超 胡森 王世杰 许若鹏 于 2020-12-25 设计创作，主要内容包括：本发明公开了一种用于切相调光电源的维持电流电路,包括AC输入,AC输入分别连接有整流器和LED驱动电源,LED驱动电源连接有LED,整流器分别连接有可控负载电路和相角检测与开关控制电路,相角检测与开关控制电路连接有开关,开关与可控负载电路连接,可控负载电路、开关和相角检测与开关控制电路组成A部分,AC输入包括L、N、切向调光器和F1,N与整流器直接连接,L连接切相调光器,切相调光器连接F1,F1与整流器连接,F1为保险丝,A部分结构包括：R1、C1、R2、R3、Z1、R4、Q1、R5、R6、Vcc、Vref和IC1；本一种用于切相调光电源的维持电流电路具有显著提升LED驱动电源的切相调光兼容性、适用于很宽的输入电压、对效率/PF/THD影响较小的优点。(The invention discloses a maintaining current circuit for a phase-cut dimming power supply, which comprises an AC input, wherein the AC input is respectively connected with a rectifier and an LED driving power supply, the LED driving power supply is connected with an LED, the rectifier is respectively connected with a controllable load circuit and a phase angle detection and switch control circuit, the phase angle detection and switch control circuit is connected with a switch, the switch is connected with the controllable load circuit, the switch and the phase angle detection and switch control circuit form a part A, the AC input comprises L, N, a tangential dimmer and a F1, the N is directly connected with the rectifier, the L is connected with the phase-cut dimmer, the phase-cut dimmer is connected with F1, the F1 is connected with the rectifier, the F1 is a fuse, and the part A structurally comprises: r1, C1, R2, R3, Z1, R4, Q1, R5, R6, Vcc, Vref, and IC 1; the holding current circuit for the phase-cut dimming power supply has the advantages of remarkably improving the phase-cut dimming compatibility of an LED driving power supply, being suitable for very wide input voltage and having small influence on efficiency/PF/THD.)

1. A holding current circuit for a phase cut dimming power supply, comprising: the LED driving power supply is connected with an LED, the rectifier is respectively connected with a controllable load circuit and a phase angle detection and switch control circuit, the phase angle detection and switch control circuit is connected with a switch, the switch is connected with the controllable load circuit, and the controllable load circuit, the switch and the phase angle detection and switch control circuit form a part A.

2. A holding current circuit for a phase-cut dimming power supply according to claim 1, wherein: the AC inputs include L, N, a tangential dimmer, and F1, the N being directly connected to the rectifier, the L being connected to a phase cut dimmer, the phase cut dimmer being connected to F1, the F1 being connected to the rectifier.

3. A holding current circuit for a phase-cut dimming power supply according to claim 1, wherein: the part A structure comprises: r1, C1, R2, R3, Z1, R4, Q1, R5, R6, Vcc, Vref and IC1, the rectifier is connected with R6, R1 and R5 in parallel, the R6 is connected with Q1, the Q1 is connected with R4, the R1 is connected with C1, the R5 is connected with Z1, IC1 and Q1, the IC1 is connected between the R1 and C1, the IC1 is connected with Vcc and Vref respectively, the IC1 and C1 are connected with R2, the other end of the R2 is connected with R3, the R3, IC1, C1, R4 and Z1 are connected with the rectifier in parallel, and the R3 is connected between RC1 and the rectifier.

4. A holding current circuit for a phase-cut dimming power supply according to claim 1, wherein: the alternative structure of the part a comprises R1, C1, R2, R3, Z1, R4, Q4, R4 and Q4, the rectifier is respectively connected with R4, R4 and R4, the R4 is connected with C4, the R4 is connected with Q4, the Q4 is connected with R4, the R4, Q4 and C4 are respectively connected with the rectifier, the Q4 is connected between R4 and C4, the Q4 is connected with C4, the R4 is connected with R4, the R4 is connected with Q4 and the rectifier, the Z4 is connected with Q4, the circuit between Z4 and R4 is connected with Q4, the rectifier is connected with Z4, the R4 and the Q4 are connected in parallel connection.

5. A holding current circuit for a phase-cut dimming power supply according to claim 1, wherein: the part A structure alternatively comprises a rectifier connection R5, wherein R5 is connected with R1 and Q1 respectively, R1 is connected with R2 and Q2, Q1 is connected with R4 and Z1 respectively, R3 is connected between R1 and R5, R3 is connected with Q2, R6 and Q1, R2, Q2, R6 and R4 are connected to the rectifier in parallel, and R1 and Q2 are connected with Z1.

6. A holding current circuit for a phase-cut dimming power supply according to claim 1, wherein: the F1 is a fuse.

Technical Field

The invention relates to the technical field of circuits, in particular to a holding current circuit for a phase-cut dimming power supply.

Background

Because phase cut dimming dimmers commonly use thyristors, one of the conduction conditions of which is to have sufficient holding current, and even with MOS dimmers, because of the more complex control circuitry, there is a need for sufficient voltage drop across the dimmer to power the control circuitry, and for holding current to ensure that sufficient voltage drop is developed across the dimmer. Therefore, in order to improve the compatibility of the LED power supply, a holding current circuit is generally required to be added to the power supply applied to the LED phase-cut dimming. The commonly used current-sustaining schemes currently on the market are:

using a main switch as a control switch for power conversion and maintaining current; the problem of the scheme is that the magnitude of the maintaining current is not controllable, larger maintaining current may occur, and the number of power supplies which can be actually connected in parallel is smaller due to the fact that the total maintaining current is too large when a plurality of power supplies are used in parallel;

secondly, a method of using a single MOS tube series resistor to detect input voltage is used for providing holding current, the scheme is greatly influenced by the input voltage waveform, when phase cut is detected by mistake, the large holding current is caused, and the efficiency is seriously influenced;

the maintaining power circuit of the discrete element is used, and the maintaining current of the triode is controlled by detecting the current, so that the scheme has the advantages of low cost, but the maintaining current is greatly influenced by the temperature; and the circuit participates in the work all the time, also is working when the power is applied to the non-phase-cut dimming circuit, has influenced THD/PF, has reduced efficiency.

Fourthly, a fixed load is used for providing a holding current, and the scheme has the greatest influence on the efficiency;

the LED driving power supply compatible with phase-cut dimming does not use a holding current circuit, so that the problem that the dimming compatibility is very poor in a light load state is caused;

the advent of a holding current circuit for a phase cut dimming power supply is needed.

Disclosure of Invention

The invention aims to provide a holding current circuit for a phase-cut dimming power supply, which has the advantages of remarkably improving the phase-cut dimming compatibility of an LED driving power supply, being suitable for very wide input voltage and having small influence on efficiency/PF/THD, and solves the problems in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a hold current circuit for cutting looks light modulation power supply, includes the AC input, the AC input is connected with rectifier and LED drive power supply respectively, LED drive power supply is connected with LED, the rectifier is connected with controllable load circuit and phase angle detection and on-off control circuit respectively, the phase angle detects and on-off control circuit is connected with the switch, the switch is connected with controllable load circuit, switch and phase angle detection and on-off control circuit constitution A part.

Preferably, the AC input includes L, N, a tangential dimmer and F1, the N is directly connected to the rectifier, the L is connected to the phase cut dimmer, the phase cut dimmer is connected to F1, and the F1 is connected to the rectifier.

Preferably, the part a structure includes: r1, C1, R2, R3, Z1, R4, Q1, R5, R6, Vcc, Vref and IC1, the rectifier is connected with R6, R1 and R5 in parallel, the R6 is connected with Q1, the Q1 is connected with R4, the R1 is connected with C1, the R5 is connected with Z1, IC1 and Q1, the IC1 is connected between the R1 and C1, the IC1 is connected with Vcc and Vref respectively, the IC1 and C1 are connected with R2, the other end of the R2 is connected with R3, the R3, IC1, C1, R4 and Z1 are connected with the rectifier in parallel, and the R3 is connected between RC1 and the rectifier.

Preferably, the a-segment structure alternatively includes R1, C1, R2, R3, Z1, R4, Q4, R4 and Q4, the rectifier is connected with R4, R4 and R4 respectively, the R4 is connected with C4, the R4 is connected with Q4, the Q4 is connected with R4, the R4, Q4 and C4 are connected with the rectifier respectively, the Q4 is connected between R4 and C4, the Q4 and C4 are connected with R4 respectively, the R4 is connected with R4 respectively, the R4 and Q4 are connected with Z4 respectively, the circuit between Z4 and R4 is connected with Q4, the Z4 is connected with the rectifier, the Z4, the R4 and the Q4 are connected in parallel, and the Q4 are connected in parallel.

Preferably, the part a structure alternatively comprises a rectifier connection R5, the R5 is connected with R1 and Q1 respectively, the R1 is connected with R2 and Q2, the Q1 is connected with R4 and Z1 respectively, the R3 is connected between the R1 and the R5, the R3 is connected with Q2, R6 and Q1, the R2, Q2, R6 and R4 are connected to the rectifier in parallel, and the R1 and the Q2 are connected with Z1.

Preferably, the F1 is a fuse.

Compared with the prior art, the invention has the following beneficial effects:

a holding current circuit for a phase-cut dimming power supply controls a controllable load to provide holding current at a proper time in a mode of detecting a phase angle, the holding current is conveniently provided, an LED driving power supply is used for AC/DC conversion and provides current for the LED load, the current is guaranteed to be provided, an alternating current voltage is converted into a direct current voltage through a rectifier, normal work of a phase angle detection and switch control circuit is guaranteed, the phase-cut state is detected through the phase angle detection and switch control circuit, the controllable load can be controlled to provide extra holding current, and normal work of a dimmer is guaranteed.

Drawings

FIG. 1 is a schematic circuit diagram of a holding current circuit for a phase-cut dimming power supply according to the present invention;

FIG. 2 is a data diagram of a holding current circuit for a phase-cut dimming power supply according to the present invention;

FIG. 3 is a schematic diagram of a hardware configuration of a holding current circuit for a phase-cut dimming power supply according to the present invention;

FIG. 4 is a schematic diagram of an alternative hardware connection scheme of a holding current circuit for a phase-cut dimming power supply according to the present invention;

fig. 5 is an alternative diagram of the hardware connection of the holding current circuit for the phase-cut dimming power supply according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by a person of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Example 1:

referring to fig. 1, 2 and 3, a holding current circuit for a phase-cut dimming power supply includes an AC input, the AC input is connected with a rectifier and an LED driving power supply respectively, the LED driving power supply is connected with an LED, the rectifier is connected with a controllable load circuit and a phase angle detection and switch control circuit respectively, the phase angle detection and switch control circuit is connected with a switch, the switch is connected with the controllable load circuit, the switch and the phase angle detection and switch control circuit form a part a, the AC input includes L, N, a tangential dimmer and a F1, N is directly connected with the rectifier, L is connected with the phase-cut dimmer, the phase-cut dimmer is connected with F1, the F1 is connected with the rectifier, and the structure of the part a includes: r1, C1, R2, R3, Z1, R4, Q1, R5, R6, Vcc, Vref and IC1, the rectifier is connected with R6, R1 and R5 in parallel, R6 is connected with Q1, Q1 is connected with R4, R1 is connected with C1, R5 is connected with Z1, IC1 and Q1, IC1 is connected between R1 and C1, IC1 is connected with Vcc and Vref respectively, R2 is connected between IC1 and C1, R3 is connected with the other end of R2, R3, IC1, C1, R4 and Z1 are connected with the rectifier in parallel, R3 is connected between RC1 and the rectifier, F1 is a fuse;

specifically, the tangential dimmer is connected with F1, F1 is connected with D1, the rectified positive voltage is connected with R1 and R5 and R6, R1 is connected with R2 and R3 in series and provides IC1 with detection voltage, R2 is optional and is added to prevent R3 from being too low in resistance value to cause the IC to detect the input signal, the reverse terminal of IC1 is connected with C1, the non-inverting terminal is connected with reference, Vcc supplies power to IC1, the output terminal of IC1 is connected with the G pole of Q1 and connected with the cathode of Z1, R4 is connected with the S pole of Q1, R6 is connected with the D pole of Q1, wherein R1, R2, R3, IC1 and C1 constitute a detection and switch control circuit, R4 is a current sampling resistor, and Z1, Q1 and R4 together complete the limitation of the maximum holding current to ensure that the maximum holding current and limit the holding current, thereby ensuring that the maximum holding current holding circuit affects the output voltage of the power supply circuit and that the output voltage is lower than PF 1 and the reverse terminal voltage of the MOS control circuit, at this time R6 is on and limits the maximum current of Q1 through R4 and R6.

Example 2:

referring to fig. 1, 2 and 4, a holding current circuit for a phase-cut dimming power supply includes an AC input, the AC input is connected to a rectifier and an LED driving power supply, the LED driving power supply is connected to an LED, the rectifier is connected to a controllable load circuit and a phase angle detection and switch control circuit, the phase angle detection and switch control circuit is connected to a switch, the switch is connected to the controllable load circuit, the switch and the phase angle detection and switch control circuit form a part a, the AC input includes L, N, a tangential dimmer and F1, N is directly connected to the rectifier, L is connected to the phase-cut dimmer, the phase-cut dimmer is connected to F1, F1 is connected to the rectifier, the part a includes R1, C1, R2, R3, Z1, R4, Q1, R6, R5 and Q2, the rectifier is connected to R1, R5 and R6, R1 is connected to C1, R5 is connected to Q2, R6 is connected to Q1, q1 is connected with R4, R4, Q2 and C1 are respectively connected with a rectifier, Q2 is connected between R1 and C1, R2 is connected between Q2 and C1, R2 is connected with R3, R3 is respectively connected with Q2 and the rectifier, Z1 is connected between R5 and Q2, a circuit between Z1 and R5 is connected with Q1, Z1 is connected with the rectifier, Z1, R4, R3 and C1 are connected in parallel, Q2 and R3 are connected in parallel, and F1 is a fuse;

specifically, the phase-cut dimmer is connected with an F1, an F1 is connected with a D1, a positive voltage after rectification is connected with an R1, an R5 is connected with an R6, an R1 is connected with an R1 and an R1 in series, and the R1 is optionally connected with the R1, so as to prevent the resistance of the R1 from being too low to provide an input signal for the base of the Q1, a C pole of the Q1 is connected with a G pole of the Q1 and connected with a cathode of the Z1, S poles of the R1 and the Q1 are connected, and D poles of the R1 and the Q1 are connected, wherein the Q1, the R1 and the C1 form a phase angle detection and switch control circuit, the R1 is a current sampling resistor, and the Z1, Q1, the R1, the Q1, the maximum holding current is connected with a sufficient holding current and the limiting circuit is connected with the on-voltage of the switch control circuit; when the voltage of the Q2 base is lower than 0.7V, Q2 is closed, and R5 controls Q1 to be opened.

Example 3:

referring to fig. 1, 2 and 5, a holding current circuit for a phase-cut dimming power supply includes an AC input, the AC input is connected with a rectifier and an LED driving power supply respectively, the LED driving power supply is connected with an LED, the rectifier is connected with a controllable load circuit and a phase angle detection and switch control circuit respectively, the phase angle detection and switch control circuit is connected with a switch, the switch is connected with the controllable load circuit, the switch and the phase angle detection and switch control circuit form a part a, the AC input includes L, N, a tangential dimmer and F1, N is directly connected with the rectifier, L is connected with the phase-cut dimmer, the phase-cut dimmer is connected with F1, F1 is connected with the rectifier, the part a includes a rectifier connection R5, R5 is connected with R1 and Q1 respectively, R1 is connected with R2 and Q2, Q1 is connected with R8 and Z1 respectively, R1 and R5 are connected with R3, R3 is connected with Q2, R6 and Q1, r2, Q2, R6 and R4 are connected to a rectifier in parallel, R1 and Q2 are connected with Z1, and F1 is a fuse;

specifically, the tangential dimmer is connected with F1, F1 and D1, the positive voltage after rectification is connected with R5, R5 is connected with R1, R2 in series and is also connected with R3, R6 in series, the c pole of Q2 is connected with the G pole of Q1 and is connected with R3, R6, the S poles of R4 and Q1, the cathode of Z1 is connected with the S pole of MOS, the anode of Z1 is connected with the base of Q2, wherein Q2, R1, R2, R5 form a phase angle detection and control circuit, R4 is a current sampling resistor, and Z1, Q1, Q2, R3, R4, R5, R6 together complete limiting the maximum holding current to ensure sufficient holding current and limit the maximum holding current, thereby ensuring the holding current and reducing the influence of the holding current on PF/THD and power supply efficiency.

In summary, the following steps: the invention relates to a maintaining current circuit for a phase-cut dimming power supply, which controls a controllable load to provide maintaining current at proper time by detecting a phase angle, an LED driving power supply is used for AC/DC conversion and providing current for the LED load, a rectifier is used for converting alternating current voltage into direct current voltage so as to ensure the normal work of a phase angle detection and switch control circuit, when the alternating current power supply is phase-cut or the voltage is lower, the maintaining current of the LED driving power supply is not enough to ensure the normal work of a dimmer, the phase angle detection and switch control circuit controls the controllable load to provide extra maintaining current so as to ensure the normal work of the dimmer when detecting that the phase-cut state is detected, and three connection modes can be freely selected according to actual conditions so as to ensure the use of the circuit.

While there have been shown and described the fundamental principles and essential features of the invention and advantages thereof, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof; the present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.