An isolated control low standby power consumption electronic single live wire switch

Abstract

The present invention discloses an electronic single-live-wire switch including an AC-DC low-standby power consumption high-frequency isolated switching power supply, which can electrically isolate the AC input and output from a low-voltage DC circuit, thereby achieving effective electrical isolation between the reference ground wire of the control circuit and the main power part of the AC input and output, and enabling the static standby power consumption when the light is turned off to be controlled within 10 milliwatts, close to zero power consumption, thereby being compatible with more low-power LED lamps or loads.

Description

Technical Field

[0001] The present invention relates to the technical field of smart home and household electrical and electrical products, and in particular to an isolation-controlled low-standby power consumption single-live-wire switch. Background Art

[0002] With the rapid development of smart home, single-live-wire smart switch has a broad market prospect. At present, most of the single-live-wire smart switches basically use the input live wire as the control circuit reference ground wire control method. Its static standby power consumption is generally large. When this type of single-live-wire smart switch is connected to a low-power LED load lamp, the LED lamp will appear slightly bright after the light is turned off due to the excessive static standby current of the single-live-wire switch, which exceeds the lamp's own shutdown current. In severe cases, abnormal phenomena such as flickering may occur, commonly known as ghost lights, which seriously restricts the popularity of single-live-wire smart switches in smart homes, indoor lighting, and household power supply control systems. Because the input live wire is used as the control ground wire of the control circuit, the AC high voltage area and the DC control circuit low voltage area cannot be effectively isolated. When the input live wire and the output load wire of the single-live-wire smart switch are reversed or connected incorrectly, abnormal phenomena such as loss of control are prone to occur, which puts forward higher requirements for the installation of the single-live-wire smart switch.

[0003] From the working principle of the single-live-wire electronic switch, it can be seen that in the off state, in order to ensure that the low-power lamp load will not be unable to shut down or ghost fire and other abnormal phenomena, the static standby current of the single-live-wire electronic switch is required to be as small as possible. When the light is turned on, in order to ensure that the high-power lamp load will not have insufficient driving current, causing abnormal phenomena such as excessive temperature rise or loss of control of the power component, the auxiliary power supply output current of the single-live-wire electronic switch is required to be as large as possible. It is not difficult to see that the above requirements are very contradictory and are also the difficulties of the single-live-wire electronic switch. If these problems cannot be effectively solved, it will be detrimental to the application and promotion of the single-live-wire electronic switch. Summary of the invention

[0004] In order to overcome and solve the many problems that occur in the design and use of existing single-live-wire electronic switches, the present invention provides an isolated controlled low standby power consumption electronic single-live-wire switch with simple process, good compatibility and high stability.

[0005] An isolated controlled low standby power consumption electronic single live wire switch comprises an AC-DC low standby power consumption high frequency isolated switching power supply, a drive circuit and a main power electronic switch circuit.

[0006] The driving circuit is controlled by the working state of the touch switch or other remote control switch. When the touch switch or other remote control switch outputs a high or low level (ON or OFF), the photoelectric coupler of the built-in bidirectional thyristor in the driving circuit is turned on, driving the bidirectional thyristor of the main power electronic switch to be in the on state, and the L live wire input is sent to the output load through the bidirectional thyristor of the main power electronic switch, and is connected to the neutral line N through the output load to form a current loop, so that the load is in a normal working state, thereby achieving the purpose of single live wire control.

[0007] The AC-DC low standby power consumption high frequency isolated switching power supply is composed of an input rectifier filter circuit, an isolated high frequency transformer, a low standby power consumption PWM high frequency conversion chip, an isolated photocoupler, an output low voltage rectifier filter circuit, a VCC reference voltage forming circuit, and an output voltage feedback circuit. When the light is turned off, the AC-DC low standby power consumption high frequency isolated switching power supply provides the required working voltage to the control circuit. Since the voltage conversion and output voltage feedback use isolation devices, the AC input and output and the low voltage DC circuit can be effectively electrically isolated, so that the reference ground wire of the control circuit and the main power part of the AC input and output can be effectively electrically isolated. Since the high frequency switch conversion component involved in the control uses a low standby power consumption PWM chip, the static standby power consumption when the light is turned off can be controlled within 10 milliwatts, which is close to zero power consumption, so that more low-power LED lamps or loads can be compatible.

[0008] The input rectifier and filter circuit is added with an LC filter circuit for suppressing differential mode and common mode interference. The circuit is composed of a filter inductor LF1 and a filter capacitor EC1, which can filter out various differential mode and common mode high-frequency interference signals generated when each power device is switched instantaneously, and can effectively reduce EMI conducted interference and radiated interference when turning off the light; the input rectifier and filter circuit can be multi-channel input.

[0009] The interior of the isolation high-frequency transformer is shielded by copper or enameled wire, which can effectively reduce the high-frequency interference generated by the high-frequency transformer of the single-live-wire switch.

[0010] The VCC reference voltage forming circuit provides the required operating voltage to the control circuit when the light is turned on. Because the reference ground line of the AC high voltage and the ground line of the control circuit are electrically isolated by the isolation component, two different reference ground lines are formed. The DC output reference voltage of the control circuit is not affected by the AC high voltage of the AC input. It is secondary stabilized by the reference voltage stabilizing circuit and then filtered by the filtering circuit to provide the required stable DC operating voltage to the control circuit.

[0011] The driving circuit is composed of a switching transistor and a photoelectric coupler with a built-in bidirectional thyristor, etc., which can control the working state of the main power electronic switch. The main power electronic switch is composed of a large current bidirectional thyristor power component, and the output is connected to the load. Due to the use of the patented technology of the present invention, stable control can be achieved regardless of whether the light is on or off, so that the stability and load compatibility of the single-live-wire electronic switch are qualitatively improved.

[0012] Preferably, the AC-DC low standby power consumption high frequency isolated switching power supply can provide a stable DC working voltage with low standby power consumption to the control circuit when the input AC voltage varies widely and the lights are off. Since its standby power consumption is close to zero when static, it can be compatible with more low-power lamps or loads, and can be isolated by an isolation transformer and an optocoupler, making the control of the control circuit more stable.

[0013] Preferably, the reference ground line of the VCC reference voltage forming circuit is connected to the low voltage side of the AC-DC low standby power consumption high frequency isolated switching power supply transformer, and is isolated from the high voltage side of the AC voltage through a transformer and a photocoupler, so that the output reference voltage of the VCC reference voltage forming circuit is more stable.

[0014] Preferably, the reference ground line of the driving circuit is connected to the low voltage side of the AC-DC low standby power consumption high frequency isolated switching power supply transformer, and is isolated from the high voltage side of the AC voltage through a transformer and a photocoupler, and its reference ground line is connected to the reference ground line of the VCC reference voltage forming circuit, so that the driving output is more stable.

[0015] The working principle of the present invention is as follows: firstly, the live wire L of the AC voltage is connected to the live wire input end of the isolated control low standby power consumption electronic single live wire switch, and then the live wire output end of the isolated control low standby power consumption electronic single live wire switch is connected to the live wire input end of the output load, and the other end of the output load is connected to the zero line N of the AC voltage. After pressing the ON key of the control panel, the photoelectric coupler of the built-in bidirectional thyristor is turned on, driving the power electronic switch SCR to turn on, the input live wire Lin and the output live wire Lout of the electronic single live wire switch are connected, and the AC input live wire voltage is output from the live wire output end through the power electronic switch, and connected to the zero line through the load lamp, forming a current closed loop, so that the load is in a normal working state. After pressing the OFF key of the control panel, the photoelectric coupler of the built-in bidirectional thyristor is cut off, no driving voltage is output, the power electronic switch SCR has no output, and the load does not work, thereby achieving the purpose of the single live wire electronic switch controlling the load. The panel involved in the control can select control modes such as touch, WIFI, 433 wireless, etc., so that its use is more extensive and has a broader market prospect.

[0016] Beneficial effects of the present invention: The present invention is an isolated control low standby power consumption electronic single live wire switch, which adopts the isolation ground wire control technology with a combination of software and hardware and low standby power consumption. Compared with other traditional single live wire switches, it can be compatible with more high-power and low-power load lamps, and the internal AC main power ground wire and the control ground wire are isolated by a high-frequency transformer and a photoelectric coupler, so that the working voltage of the entire control circuit is more stable and the operation is more reliable. Due to the use of the AC-DC high-frequency and efficient PWM switch conversion circuit with low standby power consumption, its conversion efficiency is higher, the temperature rise is lower, the service life is greatly improved, and it has the advantages of convenient control, simple process, safety and reliability, high cost performance, and easy mass and automated production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the circuit of embodiment 1 of the present invention.

[0018] Figure 2 Schematic diagram of a VCC reference voltage forming circuit in a circuit of Embodiment 2 of the present invention.

[0019] Figure 3 It is a schematic diagram of a three-way low standby power consumption switching power supply circuit according to Embodiment 3 of the present invention.

[0020] Figure 4 It is a schematic diagram of a three-way drive circuit and a main power electronic switch circuit according to Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings.

[0022] Example 1

[0023] like Figure 1As shown, the present invention relates to an isolated controlled low standby power consumption electronic single live wire switch, comprising: an input rectifier filter circuit, which is composed of a first bridge stack DL1, a filter inductor LF1, a capacitor EC1, etc.; an isolated high-frequency transformer T1; a low standby power consumption PWM high-frequency conversion chip U1; an isolated photoelectric coupler PC1; an output low-voltage rectifier filter circuit, which is composed of a diode D3, a capacitor EC3, a diode D4, a capacitor EC4, etc.; a VCC reference voltage forming circuit, which is composed of a bridge stack DL3, a capacitor EC5, a diode D5, a three-terminal voltage regulator U3, etc.; a voltage sampling feedback circuit, which is composed of resistors R7-R10, a chip U2, a capacitor C3, etc.; a drive circuit, which is composed of resistors R2-R6, a transistor BG1, a chip U4, etc.; a main power electronic switch, which is composed of a thyristor SCR1, a voltage regulator DW1, a voltage regulator DW2, a varistor TVR1, etc.; the input rectifier filter circuit is connected to the AC input live wire Lin and the multi-channel output live wires Lout. The isolated high-frequency transformer is connected to the output of the input multi-channel rectifier filter circuit. The low standby power consumption PWM high-frequency conversion chip U1 is connected to the isolated high-frequency transformer T1 and the isolated photoelectric coupler PC1. The output low-voltage rectifier filter circuit is connected to the VCC reference voltage forming circuit to provide the required working voltage to the whole machine control circuit and the drive circuit. The voltage sampling feedback circuit controls the duty cycle width of the low standby power consumption PWM high-frequency conversion chip U1 through the isolated photoelectric coupler PC1 to stabilize its output voltage. The drive circuit is connected to the switch control panel, and its working state is controlled by the panel. The main power electronic switch is controlled by the drive circuit, and the opening and closing of the power electronic switch are synchronously controlled through the intelligent control panel or wireless remote control mode, thereby playing the role of controlling the single live wire on / off and realizing the intelligent control of the single live wire electronic switch.

[0024] Example 2

[0025] like Figure 2 As shown, the rectifier device of the VCC reference voltage circuit in the circuit of the present invention can be as follows Figure 1 The single bridge stack DL3 shown can also be Figure 2 The two diodes 2D6 and 2D7 shown in the figure have the same effect.

[0026] Example 3

[0027] like Figure 3 As shown, the electronic single-live-wire switch with isolated control and low standby power consumption of the present invention has a low standby power consumption switch power supply more than the conventional single-live-wire switch. Figure 1 The low standby power consumption switching power supply part has two more live wire outputs, namely Lout2 live wire output and Lout3 live wire output, due to the additional bridge stack DL2. Figure 4The three-way drive circuit and main power electronic switch circuit can be used as a three-way isolated control low standby power electronic single live wire switch in practical applications. When adding bridge stack DL2, only one of the Lout2 live wire output and the Lout3 live wire output can be used, and the other is not used. With the two-way drive circuit and the main power electronic switch circuit, it can be used as a two-way isolated control low standby power electronic single live wire switch in practical applications. Furthermore, it can be expanded to four-way, five-way, and other multi-way isolated control low standby power electronic single live wire switches.

[0028] Example 4

[0029] like Figure 4 As shown, the drive circuit and the main power electronic switch circuit are expanded into three circuits, which can be matched with Figure 3 The embodiment forms a three-way isolation control low standby power consumption electronic single live wire switch. The VCC reference forming circuit of the three-way drive circuit and the main power electronic switch circuit uses two examples, namely, a bridge stack 1DL3 solution or a diode 2D6 / 2D7 combination solution. In practice, only one solution can be used.

[0030] Furthermore, the drive circuit and the main power electronic switch circuit can be expanded to dual-channel, quad-channel, five-channel or other multi-channel solutions.

[0031] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the concept of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An electronic single live wire switch with isolation control and low standby power consumption, characterized in that: Including AC-DC low standby power consumption high frequency isolated switching power supply, drive circuit, main power electronic switching circuit; The AC-DC low standby power consumption high frequency isolated switching power supply includes an input rectification and filtering circuit, an isolated high frequency transformer T1, a low standby power consumption PWM high frequency conversion chip U1, an isolated photoelectric coupler PC1, an output low voltage rectification and filtering circuit, a VCC reference voltage forming circuit, and an output voltage feedback circuit; The input rectification and filtering circuit comprises a first bridge stack DL1, a filtering inductor LF1 and a capacitor EC1; The output low-voltage rectification and filtering circuit includes a diode D3, a capacitor EC3, a diode D4 and a capacitor EC4; The VCC reference voltage forming circuit includes a bridge stack DL3, a capacitor EC5, a diode D5 and a three-terminal voltage regulator U3; The output voltage feedback circuit includes resistors R7-R10, a chip U2 and a capacitor C3; The driving circuit includes resistors R2-R6, transistor BG1 and chip U4; The main power electronic switch circuit includes a thyristor SCR1, a voltage regulator DW1, a voltage regulator DW2 and a varistor TVR1; The live wire input end of the AC-DC low standby power consumption high frequency isolated switching power supply is connected to the live wire input end of the main power electronic switch circuit, the live wire output end of the AC-DC low standby power consumption high frequency isolated switching power supply is connected to the live wire output end of the main power electronic switch circuit, the reference voltage output end of the AC-DC low standby power consumption high frequency isolated switching power supply is connected to the drive circuit, the AC-DC low standby power consumption high frequency isolated switching power supply controls the main power electronic switch by supplying power to the drive circuit, and is in a low power standby state when the light is off; The input rectifier filter circuit is connected to the AC input live wire Lin and the multiple output live wires Lout, the isolated high-frequency transformer T1 is connected to the multiple outputs of the input rectifier filter circuit, the low standby power consumption PWM high-frequency conversion chip U1 is connected to the isolated high-frequency transformer T1 and the isolated photoelectric coupler PC1, the output low-voltage rectifier filter circuit is connected to the VCC reference voltage forming circuit and the primary side of the isolated photoelectric coupler, and the output voltage feedback circuit controls the duty cycle width of the low standby power consumption PWM high-frequency conversion chip U1 through the isolated photoelectric coupler PC1; the drive circuit is connected to the power on / off control panel; the main power electronic switch is controlled by the drive circuit, and the power electronic switch is synchronously controlled to be turned on and off through the power on / off control panel or wireless remote control; The AC input ground line GND1 is not connected to the reference ground line GND2 in the output control circuit.

2. According to claim 1, an isolated control low standby power consumption electronic single live wire switch is characterized in that: The low standby power consumption PWM high frequency conversion chip adopts a composite IC chip with extremely low standby power consumption and high efficiency built-in power tube and duty cycle control.

3. According to claim 1, an isolated control low standby power consumption electronic single live wire switch is characterized in that: The primary ground GND1 of the isolated high-frequency transformer is connected to the secondary ground GND1 of the isolated photoelectric coupler, and the secondary side of the isolated photoelectric coupler is connected to the low standby power consumption PWM high-frequency conversion chip, which are the same reference ground wire, and the corresponding reference ground wire is GND1.

4. According to claim 1, the electronic single live wire switch with isolation control and low standby power consumption is characterized in that: The ground wire GND2 of the VCC reference voltage forming circuit is connected to the ground wire GND2 of the output voltage feedback circuit and to the ground wire GND2 of the driving circuit. The ground wire GND2 of the driving circuit is connected to the ground wire GND2 of the control panel or the wireless remote control circuit, and its corresponding reference ground wire is GND2.

5. The electronic single live wire switch with isolation control and low standby power consumption according to claim 1, characterized in that: The isolation control low standby power consumption electronic single live wire switch is in the form of single-circuit, double-circuit, triple-circuit or multi-circuit.

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