CN214481369U - Wireless power supply's self-adaptation LED table lamp device - Google Patents

Abstract

The utility model discloses a wireless power supply self-adaptive LED table lamp device, which comprises a fixed part and a movable part; the fixed part comprises a power supply circuit and a main circuit powered by the power supply circuit, wherein the main circuit comprises a first brightness detection circuit, a human body infrared monitoring circuit, a high-frequency full-control inverter circuit, a first compensation network circuit, a phase-controlled capacitance adjusting circuit and a wireless power transmitting circuit; the movable part comprises a wireless power receiving line circuit which forms wireless power transmission with the wireless power transmitting circuit, and a second compensation network circuit, a high-frequency bridge rectifier circuit, a second brightness detection circuit, an LED brightness adjusting circuit and an LED light source circuit which are powered by the wireless power receiving line circuit. The utility model has the advantages of it is following and effect: the LED table lamp can be wirelessly powered without power failure, automatically adjusts light according to ambient light, keeps unchanged brightness when moving, lights when people come, and is turned off when people leave the lamp, and the LED table lamp is applicable to LED table lamps of different models.

Description

Wireless power supply's self-adaptation LED table lamp device

Technical Field

The utility model relates to a LED light source illumination field, in particular to wireless power supply's self-adaptation LED table lamp device.

Background

The LED lamp is widely applied to various fields of modern society as a new generation of lighting source, the traditional LED lamp in the prior art has no dimming function, and the LED lamp is fully loaded and output no matter whether the light of the use environment is bright or not, which causes energy waste to a certain extent; the dimmable LED lamps are manually adjusted by adopting buttons, and the brightness cannot be continuously and automatically adjusted; when power is suddenly cut off or the power supply fails, the desk lamp cannot normally emit light. Meanwhile, most of the existing table lamps are directly connected with a power supply for use, the placement range of the table lamps is greatly limited, and the table lamps are not changed due to power supply connection in the moving process. In addition, the existing LED table lamp adopts manual power on and power off to turn on and off, and is unchangeable for users in many occasions. Therefore, there is a need to design a wireless power supply LED table lamp that can sense the brightness of ambient light to perform automatic dimming, does not need power supply connection, does not change brightness when moving, and is turned on when people come and is turned off, so as to solve the above problems.

SUMMERY OF THE UTILITY MODEL

The shortcoming and not enough to proposing in the background art, the utility model provides a wireless power supply's self-adaptation LED table lamp device through integrated wireless power transmitting and receiving circuit, control circuit, detection circuitry, drive current regulating circuit, realizes that LED table lamp does not cut off power supply, according to environment light automatic dimming, luminance unchangeable when removing, people come the lamp and bright the people and go out from the lamp to applicable in different model LED table lamps.

The above technical purpose of the present invention can be achieved by the following technical solutions: a wireless power supply self-adaptive LED table lamp device comprises a fixed part and a movable part;

the fixed part comprises a power supply circuit and a main circuit powered by the power supply circuit, and the main circuit comprises a first brightness detection circuit, a human body infrared monitoring circuit, a high-frequency full-control inverter circuit, a first compensation network circuit, a phase control capacitance adjusting circuit and a wireless power transmitting circuit;

the movable part comprises a wireless power receiving line circuit which forms wireless power transmission with the wireless power transmitting circuit, and a second compensation network circuit, a high-frequency bridge rectifier circuit, a second brightness detection circuit, an LED brightness adjusting circuit and an LED light source circuit which are powered by the wireless power receiving line circuit.

The further setting is that: the power supply circuit consists of a power frequency rectification filter circuit, an energy storage unit and a power supply selection circuit;

the power frequency rectifying and filtering circuit is composed of a rectifying diode D_P1Rectifier diode D_P2Rectifier diode D_P3Rectifier diode D_P4And a filter capacitor C₁The rectifier diode D_P1And a rectifier diode D_P3Is connected with one end of a power supply, and the other end of the power supply is connected with a rectifier diode D_P2And the anode of the rectifier diode DP4, the rectifier diode D_P1Negative electrode of (2) and rectifier diode D_P2Is connected with the cathode of the rectifier diode D_P3And a rectifier diode D_P4Is connected with the positive pole of the filter capacitor C₁Is connected to the rectifying diode D_P2The other end of the anode is connected with a rectifier diode D_P4The positive electrode of (1);

the power supply selection circuit comprises a switch K₂And switch K₃SaidSwitch K of₂And switch K₃All adopt single-pole double-throw switches, the switch K₂And switch K₃The public end of the energy storage unit is connected with the main circuit, the first connecting end of the energy storage unit is connected with the output end of the power frequency rectifying and filtering circuit, and the second connecting end of the energy storage unit is connected with the two ends of the energy storage unit.

The further setting is that: the first brightness detection circuit comprises a resistor R₁And a photoresistor R_GPThe two are connected in series and then connected with the two ends of the main circuit; the human body infrared monitoring circuit comprises a resistor R₂And human body infrared detector G_RThe two are connected in series and then connected with the two ends of the main circuit.

The further setting is that: the high-frequency full-control inverter circuit comprises a bridge type DC/AC inverter circuit formed by four full-control power switching devices.

The further setting is that: the first compensation network circuit, the phase control capacitance adjusting circuit and the wireless electric energy transmitting circuit are respectively provided with an inductor L₁And a compensation capacitor C_PAnd a transmitting coil L_PThe components of the composition are as follows,

the transmitting coil L_PAnd a compensation capacitor C_PConnected in parallel with the inductor L₁After being connected in series, the output end of the high-frequency full-control inverter circuit is connected;

the compensation capacitor C_PBy a fixed capacitor C_P1And a phase control capacitor connected in parallel, wherein the phase control capacitor is composed of a capacitor C_P2And two reverse switching tubes P₅And P₆Are connected in series.

The further setting is that: the wireless power receiving line circuit and the second compensation network circuit comprise a receiving coil L_SAnd a capacitor C connected in parallel therewith_S。

The further setting is that: the high-frequency bridge type rectifying circuit is composed of a rectifying diode D₁Rectifier diode D₂Rectifier diode D₃Rectifier diode D₄And a filter capacitor C₂The rectifier diode D₁And a rectifier diode D₃Is connected to the negative pole of the receiving coil L, and is connected to the negative pole of the receiving coil L_SOne end of (1), a receiving coil L_SIs connected to the rectifying diode D at the other end₂And a rectifier diode D₄The negative pole of (2), the rectifier diode D₁Negative electrode of (2) and rectifier diode D₂Is connected with the cathode of the rectifier diode D₃And a rectifier diode D₄Is connected with the positive pole of the filter capacitor C₂Is connected to the rectifying diode D₂The other end of the anode is connected with a rectifier diode D₄The positive electrode of (1).

The further setting is that: the second brightness detection circuit comprises a resistor R_SAnd a photoresistor R_GSThe two are connected in series and then connected with a filter capacitor C₂At both ends of the same.

The further setting is that: the LED brightness adjusting circuit and the LED light source circuit comprise power switch tubes Q connected with each other_SLED light source and stationary flow automatically controlled ware.

The utility model has the advantages that:

the utility model provides a pair of wireless power supply's self-adaptation LED table lamp device through integrated wireless power transmitting and receiving circuit, control circuit, detection circuitry, drive current regulating circuit, realizes that LED table lamp does not cut off power supply wireless, according to environment light automatic dimming, when removing luminance unchangeable, people come the light and bright people and go out from the lamp to applicable in different model LED table lamps.

The following examples are provided to further illustrate the advantageous effects.

Drawings

FIG. 1 is a structural view of a fixing portion in the embodiment;

FIG. 2 is a structural view of a movable portion in the embodiment;

FIG. 3 is a circuit diagram of a fixed portion in the embodiment;

FIG. 4 is a circuit diagram of a movable portion in the embodiment;

FIG. 5 shows an exemplary embodiment of a compensation capacitor C_PA circuit diagram of (a);

FIG. 6 is a flow chart of the automatic control of the fixed part and the desk lamp in the embodiment;

FIG. 7 is a flowchart of automatic adjustment control of the movable portion and the light emission luminance in the embodiment;

FIG. 8 is a waveform diagram illustrating the operation of the phase control capacitance adjusting circuit in the embodiment;

FIG. 9 is a graph showing the relationship between the phase angle and the equivalent capacitance and the resonance angular frequency in the embodiment;

FIG. 10 is a graph showing the relationship between the luminance of the LED and the auto-tuning parameter α in the embodiment.

In the figure: 11. a power frequency rectifying and filtering circuit; 12. an energy storage unit; 13. a power supply selection circuit; 14. a first luminance detection circuit; 15. a human body infrared monitoring circuit; 16. a high-frequency full-control inverter circuit; 17. a first compensation network circuit; 18. a phase control capacitance adjusting circuit; 19. a wireless power transmitting circuit; 21. a wireless power receiving line circuit; 22. a second compensation network circuit; 23. a high-frequency bridge rectifier circuit; 24. a second brightness detection circuit; 25. an LED brightness adjusting circuit; 26. LED light source circuit.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1 to 5, a wireless power supply adaptive LED table lamp device includes a fixed part and a movable part;

the fixed part comprises a power supply circuit and a main circuit powered by the power supply circuit, wherein the main circuit comprises a first brightness detection circuit 14, a human body infrared monitoring circuit 15, a high-frequency full-control inverter circuit 16, a first compensation network circuit 17, a phase control capacitance adjusting circuit 18 and a wireless power transmitting circuit 19;

the movable part comprises a wireless power receiving line circuit 21 which forms wireless power transmission with the wireless power transmitting circuit 19, and a second compensation network circuit 22, a high-frequency bridge rectifying circuit 23, a second brightness detection circuit 24, an LED brightness adjusting circuit 25 and an LED light source circuit 26 which are powered by the wireless power receiving line circuit.

The power supply circuit is composed of a power frequency rectification filter circuit 11, an energy storage unit 12 and a power supply selection circuit 13;

the power frequency rectifying and filtering circuit 11 is composed of a rectifying diode D_P1Rectifier diode D_P2Rectifier diode D_P3And a machineCurrent diode D_P4And a filter capacitor C₁The rectifier diode D_P1And a rectifier diode D_P3Is connected with one end of a power supply, and the other end of the power supply is connected with a rectifier diode D_P2And a rectifier diode D_P4The negative pole of (2), the rectifier diode D_P1Negative electrode of (2) and rectifier diode D_P2Is connected with the cathode of the rectifier diode D_P3And a rectifier diode D_P4Is connected with the positive pole of the filter capacitor C₁Is connected to the rectifying diode D_P2The other end of the anode is connected with a rectifier diode D_P4The positive electrode of (1);

the power selection circuit 13 comprises a switch K₂And switch K₃Switch K₂And switch K₃All adopt a single-pole double-throw switch, switch K₂And switch K₃The common end of the energy storage unit is connected with the main circuit, the first connecting end is connected with the output end of the power frequency rectifying and filtering circuit 11, and the second connecting end is connected with the two ends of the energy storage unit 12.

It should be noted that the switch K is turned on or off₂And switch K₃The switching between the power supply and the energy storage unit 12 can be realized; the power supply source is external alternating current.

The first brightness detection circuit 14 includes a resistor R₁And a photoresistor R_GPThe two are connected in series and then connected with the two ends of the main circuit; the human body infrared monitoring circuit 15 comprises a resistor R₂And human body infrared detector G_RThe two are connected in series and then connected with the two ends of the main circuit. Photoresistor R_GPAnd human body infrared detector G_RCan be purchased directly from the market as a commercially available component.

The high-frequency full-control inverter circuit 16 comprises a bridge type DC/AC inverter circuit composed of four full-control power switching devices. In fig. 3, four fully-controlled power switches are respectively corresponding to P₁、P₂、P₃And P₄。

Wherein the first compensation network circuit 17, the phase control capacitance adjusting circuit 18 and the wireless power transmitting circuit 19 are composed of inductorsL₁And a compensation capacitor C_PAnd a transmitting coil L_PThe components of the composition are as follows,

transmitting coil L_PAnd a compensation capacitor C_PConnected in parallel with the inductor L₁After being connected in series, the output end of the high-frequency full-control inverter circuit 16 is connected;

compensation capacitor C_PBy a fixed capacitor C_P1And a phase control capacitor connected in parallel, wherein the phase control capacitor is composed of a capacitor C_P2And two reverse switching tubes P₅And P₆Are connected in series.

Wherein, the wireless power receiving line circuit 21 and the second compensation network circuit 22 comprise a receiving coil L_SAnd a capacitor C connected in parallel therewith_S。

It should be noted that, in this embodiment, the first compensation network circuit 17 and the second compensation network circuit 22 are provided to improve the transmission power and the transmission efficiency of the wireless power transmission system; the first compensation network circuit 17 and the second compensation network circuit 22 are both resonant compensation networks. In normal use of the desk lamp, when the movable part is far away from the fixed part, the equivalent load resistance of the system becomes very large, in order to ensure the operation safety of the system, the first compensation network circuit 17 of the fixed part in the embodiment adopts an LCL type structure, while the LED light source requires constant current driving, and the second compensation network circuit 22 of the movable part adopts a P type structure, so as to form an LCL-P type topology structure. Transmitting coil (equivalent to inductance L)_PAnd a smaller resistor in series) with a compensation capacitor C_PConnected in parallel with the resonance compensation inductor L₁Are connected in series. Receiving coil (equivalent to inductance L)_SAnd a smaller resistor in series) with a compensation capacitor C_SAre connected in parallel. Under the resonance state of the LCL-P topological structure, when the resonance frequency is omega, the output current of the compensation network is I_O＝MV_S/(jωL_SL_P) And M is the mutual inductance between the transmitting coil and the receiving coil, and depends on the position between the transmitting coil and the receiving coil, so that the adopted LCL-P type resonance compensation circuit has constant current output characteristics and is suitable for constant current driving of the LED table lamp. However, when the distance between the transmitting coil and the receiving coil changes, namely the LED light source is moved, the output current Io changes, and the controllable switch is adopted in the implementationThe tube automatically adjusts the driving current, and ensures that the brightness of the LED light source is unchanged in the moving process.

Wherein the high frequency bridge rectifier circuit 23 is composed of a rectifier diode D₁Rectifier diode D₂Rectifier diode D₃Rectifier diode D₄And a filter capacitor C₂Composition, rectifier diode D₁And a rectifier diode D₃Is connected to the negative pole of the receiving coil L, and is connected to the negative pole of the receiving coil L_SOne end of (1), a receiving coil L_SIs connected to the rectifying diode D at the other end₂And a rectifier diode D₄Negative pole of (D), rectifier diode₁Negative electrode of (2) and rectifier diode D₂Is connected with the negative pole of the rectifier diode D₃And a rectifier diode D₄Is connected with the positive electrode of the filter capacitor C₂Is connected to the rectifying diode D₂The other end of the anode is connected with a rectifier diode D₄The positive electrode of (1).

The second brightness detection circuit 24 includes a resistor R_SAnd a photoresistor R_GSThe two are connected in series and then connected with a filter capacitor C₂At both ends of the same.

The LED brightness adjusting circuit 25 and the LED light source circuit 26 comprise a power switch tube Q connected with each other_SThe LED light source and the current stabilizing electric controller; the LED light source is equivalent to the resistor R in figure 4_LThe current-stabilizing electric controller is L in the attached figure 4₂。

Hereinafter, the control process of the present embodiment is explained in detail:

(1) automatic dimming control method for LED (light emitting diode) when ambient light changes

Using a photo-resistor R_GSMatched power switch tube Q_SAnd the automatic adjustment of the LED brightness is realized. Photoresistor R_GSThe resistance value of the light source is reduced along with the increase of light intensity and the increase of temperature, and a photoresistor R is adopted_GS(combining with a temperature compensation resistor with positive temperature coefficient) detecting the brightness of the ambient light, when the ambient light is dark to a certain degree and people exist around, the desk lamp is lighted, and a power switch tube Q is adopted_SThe on-off control of the LED controls the driving current of the LED, and the LED can be automatically adjusted according to the brightness of the environmentLuminous intensity of the LED light source. Power switch tube Q_SA power switching device driven by rectangular wave signal, wherein when the driving signal is at high level, the power switching tube Q_SConducting, and enabling the LED driving current to be 0; when the driving signal is at low level, the power switch tube Q_SAnd when the LED is cut off, the LED drives the current to be maximum. Due to the photoresistor R_GSThe bright resistance (including temperature compensation resistance) is 10k omega magnitude, the LED equivalent resistance is 0.1k omega magnitude, and the output current Io and the input current I of the resonance compensation network_dEquivalent, power switch tube Q_SThe duty ratio of the driving signal is alpha, then the LED drives the current I_L＝(1-α)I_dAnd the LED driving current can be adjusted by changing alpha, so that the LED brightness adjustment is realized. The photoresistor RGS detects the ambient light, compares with the set brightness, and the external control circuit generates a switching tube driving signal rectangular wave, automatically adjusts alpha according to the change of the ambient light, and adjusts the driving current of the LED, thereby realizing the automatic dimming of the LED. By measuring the photoresistor R_GSBy passing a current and a voltage across the two terminals, a photoresistor R can be obtained_GSResistance value R of_GSThereby obtaining the ambient light intensity. The greater the ambient light intensity is, the greater the photoresistor R_GSThe smaller the value. If the resistance value R is_GSGreater than a set value R_oIndicating that the ambient light brightness is lower than the set brightness if the resistance value R_GSLess than a set value R_oIndicating that the ambient light brightness is higher than the set brightness.

(2) Control method for automatic dimming when LED light source moves

When other parameters of the desk lamp system are unchanged and only the position of the LED light source is moved, the mutual inductance M of the transmitting coil and the receiving coil is reduced, the output current Io of the mobile side resonance compensation circuit is reduced, and the power switch tube Q can be reduced_STo increase the driving current I of the LED_LAnd adjusting the brightness of the LED. Comparing the resistance value of the resistor RGS with the resistance value corresponding to the set brightness to obtain the power switch tube Q_SThe duty ratio alpha of the driving signal and the LED luminance are automatically adjusted along with the movement of the light source, so that the total luminance obtained by a user is kept unchanged when the LED light source moves. In order to reduce the fluctuation of the drive currentA current stabilizing electric controller L with small internal resistance and large self-inductance is connected in series on the LED₂And the stability of the LED brightness in the automatic dimming process is ensured.

(3) Automatic on-off control circuit and control method for desk lamp

The self-adaptive desk lamp adopts a human body infrared detector G_RThe monitoring circuit realizes automatic on-off. As shown in FIG. 3, a human body infrared detector G_RThe pyroelectric infrared sensing device is a pyroelectric infrared sensing device and has extremely strong sensing capability on infrared rays with specific wavelengths. The central wavelength of infrared rays radiated by a human body is 9-10 mu m, the wavelength range of light passing through a filter lens at the top end of the pyroelectric infrared sensing device is 7-10 mu m, the filter lens is just suitable for detecting infrared rays radiated by the human body, and the infrared rays with other wavelengths are absorbed by the filter. The induction angle is less than 100 degrees of cone angle, and the induction distance is adjustable between 3m and 7 m. When people approach, the pyroelectric infrared sensing device outputs high-level signals when detecting the infrared spectrum of human body radiation, and the control circuit of the fixed part controls K₁On, the lamp is automatically lighted. When people leave or the ambient light is strong enough, the pyroelectric infrared sensing device outputs low level and controls the switch K₁And when the LED lamp is turned off, and the functions of turning on the lamp when a person comes and turning off the lamp when the person goes are realized.

(4) Measuring circuit and control process of LED table lamp

The measuring circuit comprising a fixed part of a photoresistor R_GPVoltage current, transmitting coil current, photoresistor R of moving part_GSMeasurement of voltage current, receive coil current, LED drive current, etc. The fixed part and the mobile part are respectively controlled, so that error codes and information delay caused by wireless communication between the two parts are avoided. In the process of realizing the equality of the working frequency and the natural resonant frequency of the transmitting part and the receiving part, the inductance L of the receiving coil is firstly used_SAnd a compensation capacitor C_SAnd calculating theoretical resonant frequency omegas, keeping the output voltage of the high-frequency inverter circuit of the fixed part unchanged and finely adjusting the working frequency near omegas until the current value measured by the receiving coil is the maximum, namely the natural resonant frequency of the receiving circuit. Thereafter, the phase control capacitance is adjusted, with the operating frequency being maintained, until the measurement of the transmitter coil is obtainedThe current is maximum, and the resonance of the compensation circuit at two sides is realized. The electric energy transmission based on wireless power supply and the automatic on-off control process of the LED are shown in fig. 6, and the wireless energy receiving and automatic LED light brightness adjusting control process is shown in fig. 7.

In addition, fig. 8 is a waveform diagram of the operation of the phase control capacitance adjusting circuit in the embodiment; FIG. 9 is a graph showing the relationship between the phase angle and the equivalent capacitance and the resonance angular frequency in the embodiment; FIG. 10 is a graph showing the relationship between the luminance of the LED and the auto-tuning parameter α in the embodiment.

Application examples

First, implementation of wireless power transmission, ambient light brightness detection and automatic on-off control of desk lamp on desk lamp fixing part

K in the fixed part in the present embodiment₁Is formed by connecting a relay and a manual switch in series, and a photoresistor R_GP(including series positive temperature coefficient thermistor to compensate temperature), the full-control power switch device of the inverter bridge arm adopts MOSFET tube. When a user approaches the desk lamp, the commercial power AC power switch K is manually switched on₁，K₁Is a relay with a manual switch. Bridge rectifier circuit and filter capacitor C formed by passing commercial power alternating current through four power diodes₁And obtaining stable direct current voltage. DC output terminal A, A' and switch K for power supply conversion₂And K₃And (4) connecting. Obtaining the resistance RGP from the terminal voltage/current of the photoresistor, and taking the photoresistor corresponding to the environmental light brightness required by the LED which does not need to be lighted as R_0PIf R is_GP<R_0PIndicating that the current ambient light is sufficient to meet the brightness requirement, the control circuit drives the relay K₁And (5) disconnecting. If R is_GP>R_0PAnd indicating that the current ambient light brightness can not meet the requirement, and switching on the relay. A bridge type inverter circuit formed by four controllable bridge arms is selected, and each bridge arm is formed by reversely connecting MOSFET tubes and diodes in parallel. The stable DC voltage passes through an inverter circuit to generate a high-frequency rectangular AC voltage, and then passes through a capacitor L₁、C_PAnd L_PThe resonance compensation network of LCL topology structure can obtain high-frequency sine AC current, and the transmitting coil L is used for transmitting the high-frequency sine AC current_PThe generated high-frequency electromagnetic field is emitted out to provide wireless electric energy for the LED table lamp.

The working frequency is about 80kHz and meets omega^-2＝L_PC_P＝L_SC_SAnd L is₁＝L_PAdjustable compensation capacitor C_pL of wireless power receiving end of mobile part of LED table lamp according to work_SAnd C_SC can be adjusted by using phase control capacitors_PAnd (4) meeting the requirement.

Human body infrared detector G is selected_RThe on-off of the LED desk lamp is monitored. In the working process of the LED table lamp, if a user leaves, the human body infrared detector G_ROutput low level, control circuit drive relay K₁Delaying action, if the leaving time does not exceed the set time, the user approaches the human body infrared detector G_RAnd outputting a high level, and keeping KI on. If the leaving time exceeds the set time, K₁And the lamp is turned off when the lamp is turned off.

If the LED desk lamp is suddenly powered off or the power frequency alternating current fails in the lighting process, the power supply change-over switch K₂/K₃The BB terminal of the standby energy storage direct current power supply EG is connected, and uninterrupted wireless electric energy can be provided for the LED table lamp.

After alternating square wave voltage generated by the bridge type inverter circuit P1-P4 is filtered by the LCL, the voltage at two ends of the EF becomes the peak value U_EFSine voltage u of_EFAlso the transmitting coil L_pThe voltage of the emitted high frequency electromagnetic field determines the wireless power transmission power of the system of the patent, and is one of the determinants of the power available to the movable part of the table lamp (another determinant is the degree of mutual inductance between the transmitter coil and the receiver coil). At u_EFPositive half period of (d) when u_EFGreater than a certain voltage U_dcTime P₆Turning off; and at u_EFNegative half period of (d) when u_EFIs less than-U_dcTime P₅Turn off, U as required_dcThe size of the control switch tube P can be determined₅、P₆Phase angle theta ═ sin^-1(U_dc/U_EF)。

For different LED table lampsPosition corresponding to L_P、C_P1、C_P2、L_SAnd C_SIn a different way, adjust P₅And P₆When ω is satisfied, the phase angle of^-2＝L_SC_S＝L_PC_P＝L_PC_P1+L_PC_P2[1-cosθ+(π/2-θ)sinθ]And meanwhile, the resonance of the wireless power supply system of the LED table lamp is realized, and the wireless power transmission power and the transmission efficiency of the system are maximized. The waveform of the operation of the phase control capacitance tuning circuit is shown in fig. 8, wherein the operating frequency is 80 kHz. The relationship between the phase angle and the equivalent capacitance and the resonance angular frequency is shown in FIG. 9, where C is_P1＝C_P2Frequency of resonance omega₀Corresponding resonant capacitor C_P0＝1.5C_P1。

Second, implementation of wireless power receiving of movable part of desk lamp and automatic dimming of desk lamp

By a receiving coil L_SAnd a capacitor C_SThe high-frequency alternating current induced voltage is obtained by connecting in parallel to form a wireless power induction receiving circuit₁-D₄And C₂The formed bridge type high-frequency rectifying and filtering circuit obtains stable direct current. Selecting a photo-resistance sensor R_GSDetecting brightness under LED lamp-on condition, power switch tube Q_SAnd a current stabilizing inductor L₂Forming a current regulation circuit for regulating the drive current I of the LED_L，I_L＝(1-α)I_dChanging the power switching tube Q_SThe duty ratio of the driving signal is alpha, so that the LED driving current can be adjusted, and the LED brightness adjustment is realized.

Taking the photosensitive resistance value corresponding to the total brightness required when the LED table lamp is lighted as R_0SIf R is_GS>R_0SWhen the current brightness is lower than the required value, the control circuit reduces the duty ratio alpha and drives the current I_LAnd the LED brightness is increased. If R is_GS<R_0SWhen the current brightness is higher than the required value, the control circuit increases the duty ratio alpha and drives the current I_LAnd the brightness of the LED is reduced. Up to R_GS＝R_0SConstant duty cycle alpha, drive current I_LThe brightness of the LED is unchanged. The brightness suitable for human eyes is 500lux, and the relationship between the required LED luminance and the duty ratio alpha of the corresponding driving signal under different environmental brightness is shown in FIG. 10. Because of the power switch tube Q_SThe frequency of the driving signal is about 80kHz, and the driving signal is connected with a current stabilizing electric controller in series, so that the LED can not flicker in the automatic dimming process.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications to the present embodiment without inventive contribution as required after reading the present specification, but all of them are protected by patent laws within the scope of the claims of the present invention.

Claims (9)

1. The utility model provides a wireless power supply's self-adaptation LED table lamp device which characterized in that: comprises a fixed part and a movable part;

the fixed part comprises a power supply circuit and a main circuit powered by the power supply circuit, and the main circuit comprises a first brightness detection circuit (14), a human body infrared monitoring circuit (15), a high-frequency full-control inverter circuit (16), a first compensation network circuit (17), a phase control capacitance adjusting circuit (18) and a wireless power transmitting circuit (19);

the movable part comprises a wireless power receiving line circuit (21) which forms wireless power transmission with a wireless power transmitting circuit (19), and a second compensation network circuit (22), a high-frequency bridge rectifier circuit (23), a second brightness detection circuit (24), an LED brightness adjusting circuit (25) and an LED light source circuit (26) which are powered by the wireless power receiving line circuit.

2. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the power supply circuit consists of a power frequency rectification filter circuit (11), an energy storage unit (12) and a power supply selection circuit (13);

the power frequency rectifying and filtering circuit (11) is composed of a rectifying diode D_P1Rectifier diode D_P2Rectifier diode D_P3Rectifier diode D_P4And a filter capacitor C₁The rectifier diode D_P1And a rectifier diode D_P3Is connected with one end of a power supply, and the other end of the power supply is connected with a rectifier diode D_P2And a rectifier diode D_P4The negative pole of (2), the rectifier diode D_P1Negative electrode of (2) and rectifier diode D_P2Is connected with the cathode of the rectifier diode D_P3And a rectifier diode D_P4Is connected with the positive pole of the filter capacitor C₁Is connected to the rectifying diode D_P2The other end of the anode is connected with a rectifier diode D_P4The positive electrode of (1);

the power supply selection circuit (13) comprises a switch K₂And switch K₃The switch K2 and the switch K3 both adopt single-pole double-throw switches, the common end of the switch K2 and the switch K3 is connected to the main circuit, the first connecting end is connected to the output end of the power frequency rectifying and filtering circuit (11), and the second connecting end is connected to the two ends of the energy storage unit (12).

3. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the first brightness detection circuit (14) comprises a resistor R₁And a photoresistor R_GPThe two are connected in series and then connected with the two ends of the main circuit; the human body infrared monitoring circuit (15) comprises a resistor R2 and a human body infrared detector G_RThe two are connected in series and then connected with the two ends of the main circuit.

4. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the high-frequency full-control inverter circuit (16) comprises a bridge type DC/AC inverter circuit formed by four full-control power switching devices.

5. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the first compensation network circuit (17), the phase control capacitance adjusting circuit (18) and the wireless power transmitting circuit (19) are composed of an inductor L₁And a compensation capacitor C_PAnd a transmitting coil L_PThe components of the composition are as follows,

the transmitting coil L_PAnd a compensation capacitor C_PConnected in parallel with the inductor L₁After being connected in series, the output end of the high-frequency full-control inverter circuit (16) is connected;

the compensation capacitor C_PBy a fixed capacitor C_P1And a phase control capacitor connected in parallel, wherein the phase control capacitor is composed of a capacitor C_P2And two reverse switching tubes P₅And P₆Are connected in series.

6. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the wireless power receiving line circuit (21) and the second compensation network circuit (22) comprise a receiving coil L_SAnd a capacitor C connected in parallel therewith_S。

7. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the high-frequency bridge rectifier circuit (23) is composed of a rectifier diode D₁Rectifier diode D₂Rectifier diode D₃Rectifier diode D₄And a filter capacitor C₂The rectifier diode D₁And a rectifier diode D₃Is connected to the negative pole of the receiving coil L, and is connected to the negative pole of the receiving coil L_SOne end of (1), a receiving coil L_SIs connected to the rectifying diode D at the other end₂And a rectifier diode D₄The negative pole of (2), the rectifier diode D₁Negative electrode of (2) and rectifier diode D₂Is connected with the cathode of the rectifier diode D₃And a rectifier diode D₄Is connected with the positive pole of the filter capacitor C₂Is connected to the rectifying diode D₂The other end of the anode is connected with a rectifier diode D₄The positive electrode of (1).

8. The wirelessly powered adaptive LED table lamp device of claim 7, wherein: the second brightness detection circuit (24) comprises a resistor R_SAnd a photoresistor R_GSAfter the two are connected in seriesIs connected with the filter capacitor C₂At both ends of the same.

9. The wirelessly powered adaptive LED table lamp device of claim 1, wherein: the LED brightness adjusting circuit (25) and the LED light source circuit (26) comprise power switch tubes Q connected with each other_SLED light source and stationary flow automatically controlled ware.

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