CN217563814U

CN217563814U - Lamp slow-lighting control system

Info

Publication number: CN217563814U
Application number: CN202220067016.4U
Authority: CN
Inventors: 冯四德; 李贤周; 魏勇
Original assignee: Guangdong Mingfeng Power Technology Co ltd
Current assignee: Guangdong Mingfeng Power Technology Co ltd
Priority date: 2022-01-11
Filing date: 2022-01-11
Publication date: 2022-10-11
Anticipated expiration: 2032-01-11

Abstract

The utility model discloses a lamp slow-lighting control system, which comprises an input module, a control module and a control module, wherein the input module is used for being connected with a power supply; the switching voltage driving module is connected with the input module and the load to form at least part of a power supply loop; the charging module is connected with the input module; and the driving signal modulation module is respectively connected with the input module, the charging module and the switching voltage driving module, and can form different driving signals according to the charging condition so as to drive the switching voltage driving module to operate. Therefore, the luminous intensity of the load can be slowly increased along with the charging progress of the charging module, the light-on and slow-on effect is achieved under the condition that MCU control is not needed, and the practicability requirement of a low-power lamp can be effectively met.

Description

Lamp slow-lighting control system

Technical Field

The utility model relates to an automatically controlled technical field, in particular to lamps and lanterns slowly shine control system.

Background

Due to the characteristics of the LED lamp beads, after the LED lamp is electrified, the illumination intensity of the LED lamp can reach the maximum value in a short time, and human eyes are prone to discomfort. Therefore, a slow-lighting control circuit needs to be added to the lamp to achieve the effect of turning on the lamp and slowly lighting the lamp. The current dimming control circuit generally includes a Micro Control Unit (MCU) and a modulation module, where the MCU continuously adjusts a control signal input to the modulation module to drive the modulation module to generate Pulse Width Modulation (PWM) signals with different duty ratios, so as to control the brightness of the lamp to increase gradually by using a PWM control method. However, this method still relies on the control action of the MCU, and fails to meet the practical requirements of low power lamps.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a lamps and lanterns delay and shine control system can need not MCU's control and realize that the light is opened and delay the bright effect.

According to the utility model discloses a lamps and lanterns slow-lighting control system of first aspect embodiment, include:

the input module is used for being connected with a power supply;

the switching voltage driving module is connected with the input module and the load to form at least part of a power supply loop;

the charging module is connected with the input module;

and the driving signal modulation module is respectively connected with the input module, the charging module and the switching voltage driving module, and can form different driving signals according to the charging condition so as to drive the switching voltage driving module to operate.

According to the utility model discloses control system slowly shines of lamps and lanterns has following beneficial effect at least:

according to the utility model discloses lamps and lanterns slowly shine control system, including input module, the module of charging, switching voltage drive module and drive signal modulation module, when input module inserts power supply, the module of charging slowly charges for the voltage of the module of charging also slowly increases. Based on this, drive signal modulation module is according to the voltage of the module of charging, can generate duty ratio crescent drive signal, and send drive signal to switching voltage drive module with the operation of drive switching voltage drive module, and then supply the cycle of pressure and time length for the load through the adjustment of switching voltage drive module, realize the bright periodic variation that goes out of load, form different light intensity effects, so the luminous intensity of load also can be along with the slow grow of the charging progress of the module of charging, realized the effect of slowly brightening of turning on the light under the condition that need not MCU control, the circuit is simple, therefore, the low-power lamp can effectively satisfy the practicality demand of miniwatt lamps and lanterns.

According to some embodiments of the utility model, the module of charging includes electric capacity EC4, first resistance unit and second resistance unit, first resistance unit with electric capacity EC4 parallel connection is in order to constitute first parallel circuit, the one end of first parallel circuit respectively with drive signal modulation module and the one end of second resistance unit is connected, the other end ground connection of first parallel circuit, the other end of second resistance unit with input module connects.

According to the utility model discloses a some embodiments, switching voltage drive module includes switch element and vary voltage unit, switch element respectively with input module with vary voltage unit connects, switch element with drive signal modulation module connects in order to carry out the break-make according to drive signal, vary voltage unit and load connection.

According to some embodiments of the present invention, the voltage transformation unit includes a primary coil and a first secondary coil, a first end of the primary coil is connected to the input module, a second end of the primary coil is connected to the switch unit, a first end of the first secondary coil is connected to a positive pole of a load, a second end of the first secondary coil is connected to a negative pole of the load, and the first end of the first secondary coil and the second end of the primary coil are homonymy ends.

According to some embodiments of the present invention, the switching voltage driving module further includes a third resistance unit, an electric capacity C1 and a diode D4, the third resistance unit with electric capacity C1 parallel connection is in order to constitute a second parallel circuit, one end of the second parallel circuit with the negative pole of diode D4 is connected, the other end of the second parallel circuit with the input module is connected, the positive pole of diode D4 respectively with the second end of the primary coil with the switching unit is connected.

According to some embodiments of the present invention, the switch unit includes a field effect transistor, a first end of the field effect transistor is connected with the input module and a second end of the primary coil, respectively, a second end of the field effect transistor is connected with the driving signal modulation module, a third end of the field effect transistor is grounded through a current sampling resistor, and the third end of the field effect transistor is connected with the driving signal modulation module (400).

According to some embodiments of the utility model, switching voltage drive module still includes diode D5, resistance R8 and electric capacity EC3, electric capacity EC3 with resistance R8 parallel connection is in order to constitute third parallel circuit, third parallel circuit's one end respectively with diode D5's negative pole with the positive pole of load is connected, third parallel circuit's the other end respectively with the second end of first secondary coil with the negative pole of load is connected, diode D5's positive pole with the first end of first secondary coil is connected.

According to some embodiments of the utility model, still including getting the electric module, the vary voltage unit still includes second secondary, the one end ground connection of second secondary, the other end of second secondary passes through get the electric module with drive signal modulation module connects.

According to some embodiments of the utility model, it includes resistance R2, diode D3 and electric capacity EC2 to get the electric module, resistance R2's one end connect in the one end of second secondary coil, resistance R2's the other end connect in diode D3's positive pole, diode D3's negative pole respectively with drive signal modulation module and electric capacity EC 2's one end is connected, electric capacity EC 2's other end ground connection.

According to some embodiments of the utility model, the input module includes first input port, second input port and rectification unit, first input port is used for connecting power supply's live wire, second input port is used for connecting power supply's zero line, the rectification unit has first alternating current end, second alternating current end, first direct current end and second direct current end, first alternating current end with first input port connects, second alternating current end with second input port connects, first direct current end ground connection, second direct current end connect respectively in drive signal modulation module switching voltage drive module with the module of charging.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a lamp slow-lighting control system disclosed in an embodiment of the present invention;

fig. 2 is a schematic circuit diagram of a lamp slow-lighting control system according to an embodiment of the present invention.

Reference numerals:

the power supply system comprises an input module 100, a charging module 200, a switching voltage driving module 300, a transforming unit 310, a switching unit 320, a driving signal modulating module 400 and a power taking module 500.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the orientation description, such as the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., is the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplicity of description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the number, and the terms greater than, less than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood as a specific case by those skilled in the art.

As shown in fig. 1-2, a light fixture slow-lighting control system according to an embodiment of the present invention includes an input module 100, a charging module 200, a switching voltage driving module 300, and a driving signal modulating module 400. The input module 100 is used for connecting with a power supply, and the switching voltage driving module 300 is connected with the input module 100 and a load to form at least part of a power supply loop. The charging module 200 is connected to the input module 100, and the driving signal modulation module 400 is respectively connected to the input module 100, the charging module 200, and the switching voltage driving module 300, so that the driving signal modulation module 400 can form different driving signals according to the charging condition to drive the switching voltage driving module 300 to operate.

The load may include, but is not limited to, a light emitting device such as an LED lamp, a fluorescent lamp, or an incandescent lamp. Based on this, when the input module 100 is connected to the power supply, the charging module 200 charges slowly, so that the voltage of the charging module 200 also increases slowly. The driving signal modulation module 400 can generate a driving signal with a gradually increased duty ratio according to the voltage of the charging module 200, and send the driving signal to the switching voltage driving module 300 to drive the switching voltage driving module 300 to operate, so that the period and the duration of voltage supply to the load are adjusted through the switching voltage driving module 300, the on-off period change of the load is realized, different light intensity effects are formed, so that the luminous intensity of the load can also slowly increase along with the charging progress of the charging module 200, and the luminous intensity is increased to the maximum value until the charging of the charging module 200 is completed, and the light-on slow-on effect is realized under the condition without MCU control, the circuit is simple, the cost is low, and the practical requirement of a low-power lamp can be effectively met.

The utility model discloses a some embodiments, input module 100 can include first input port and second input port, and first input port is used for connecting power supply's live wire, and second input port is used for connecting power supply's zero line, and power supply can indicate the commercial power, and its power frequency is 50Hz or 60Hz, and its alternating voltage distribution range is 100V to 380V, does not specifically limit to this. Specifically, the input module 100 may further include a rectifying unit, such as a rectifying bridge shown in fig. 2, to implement a rectifying process on the input voltage. The rectifying unit has a first ac terminal, a second ac terminal, a first dc terminal and a second dc terminal, the first ac terminal is connected to the first input port, the second ac terminal is connected to the second input port, the first dc terminal is grounded, and the second dc terminal is connected to the driving signal modulating module 400, the switching voltage driving module 300, and the charging module 200, respectively.

More specifically, the second dc terminal of the rectifying unit may also be connected to the driving signal modulation module 400 through a resistor R13, so as to provide the starting voltage for the driving signal modulation module 400. The rectifying unit can also be connected with the first alternating current end of the first input port through a protection resistor RX1 to play a circuit protection role.

In the embodiment of the present invention, the charging module 200 may include a capacitor assembly, and may also be composed of a capacitor assembly and a peripheral circuit thereof. In some embodiments of the present invention, the charging module 200 may include a capacitor EC4, a first resistor unit and a second resistor unit, the first resistor unit is connected in parallel with the capacitor EC4 to form a first parallel circuit, one end of the first parallel circuit is connected to one end of the driving signal modulation module 400 and one end of the second resistor unit, the other end of the first parallel circuit is grounded, and the other end of the second resistor unit is connected to the input module 100. Specifically, as shown in fig. 2, the first resistance unit may include a resistor R15, and the second resistance unit may include a resistor R14 and a resistor R3 connected in series. The capacitor assembly and the capacitor EC4 can adopt electrolytic capacitors. As can be seen, the first resistor unit, the second resistor unit and the capacitor EC4 form a clamping circuit, which plays a role in clamping the voltage at the connection end between the driving signal modulation module 400 and the first parallel circuit, thereby implementing an overvoltage protection function. When the power supply connected to the input module 100 is turned off, the capacitor EC4 may also be rapidly discharged through the resistor R15.

In some implementations, when the input module 100 is connected to a 220V ac power supply, the resistor R14 is 1.5M Ω, the resistor R3 is 1.5M Ω, the resistor R15 is 22k Ω, and the capacitor EC4 is 100U/16V.

In some embodiments of the present invention, the driving signal modulation module 400 may generate the PWM signal according to the charging condition of the charging module 200. The driving signal modulation module 400 may directly use an analog dimming power chip, such as PM2016 or BP3378A, and the like, which is not limited in this regard. Specifically, as shown in fig. 2, the driving signal modulation module 400 at least includes a power terminal VCC, a dimming control terminal DIM, a ground terminal GND, and a signal output terminal DR. The power source terminal VCC is connected to the input module 100, the ground terminal GND is grounded, the dimming control terminal DIM is connected to the charging module 200, and the signal output terminal DR is connected to the switching voltage driving module 300, so the driving signal modulation module 400 can detect the charging voltage at both ends of the capacitor EC4 through the dimming control terminal DIM, generate a PWM signal according to the charging voltage at both ends of the capacitor EC4, and transmit the PWM signal to the switching voltage driving module 300 through the signal output terminal DR. When the PWM signal is at a high level, the switching voltage driving module 300 operates to supply voltage to the load; when the PWM signal is at a low level, the switching voltage driving module 300 does not supply voltage to the load. Therefore, in the control period of the PWM signal, the time ratio of voltage supply to voltage non-supply of the load is consistent with the duty ratio of the PWM signal, and the gradual lighting process adjustment of the load from slight brightness to 100 percent brightness is realized by adjusting the time ratio of the brightness of the load.

In some embodiments of the present invention, the switching voltage driving module 300 may include a switching unit 320, the switching unit 320 is respectively connected to the input module 100 and the load, and the switching unit 320 is connected to the driving signal modulation module 400 to be turned on or off according to the driving signal. The switching unit 320 includes, but is not limited to, an electronic device with a switching function, such as a field effect transistor or a triode, and when the PWM signal input to the switching unit 320 by the driving signal modulation module 400 is at a high level, the switching unit 320 is turned on, and the input module 100 is connected to the load; when the PWM signal is at a low level, the switching unit 320 is turned off, and the input module 100 is not connected to the load.

Further, optionally, the switching voltage driving module 300 may further include a transforming unit 310, and the transforming unit 310 is connected to the switching unit 320 and the load, respectively. When the switching unit 320 is turned on, the transforming unit 310 performs voltage transformation according to the PWM signal and the input voltage of the input module 100 to generate a positive voltage signal; when the switching unit 320 is turned off, the transforming unit 310 generates a negative voltage signal, and thus the ratio of the time during which the transforming unit 310 generates the positive voltage signal to the time during which the negative voltage signal is generated coincides with the duty ratio of the PWM signal. The transforming unit 310 may be an electronic device with a transforming function, such as a double-winding transformer or a three-winding transformer, and is not particularly limited.

In some alternative embodiments, the transforming unit 310 includes a primary coil and a first secondary coil, a first end of the primary coil is connected to the input module 100, a second end of the primary coil is connected to the switching unit 320, a first end of the first secondary coil is connected to a positive pole of the load, a second end of the first secondary coil is connected to a negative pole of the load, and the first end of the first secondary coil and the second end of the primary coil are dotted terminals.

As shown in fig. 2, when the driving signal generated by the driving signal modulation module 400 is at a high level, the primary coil of the transforming unit 310 generates a forward voltage, and the first secondary coil of the transforming unit 310 also generates a forward induced voltage to supply voltage to the load. When the driving signal modulation module 400 does not generate the driving signal or the generated driving signal is at a low level, the primary coil of the transforming unit 310 generates a negative voltage, and the negative induced voltage generated by the first secondary coil of the transforming unit 310 cannot supply power to the load.

In the case that the switching unit 320 is a field effect transistor Q1, a first end of the field effect transistor Q1 is connected to the input module 100 and a second end of the primary coil, respectively, a second end of the field effect transistor Q1 is connected to the driving signal modulation module 400, a third end of the field effect transistor Q1 is grounded through a current sampling resistor, and the third end of the field effect transistor Q1 is connected to the driving signal modulation module 400, so as to form a feedback loop. Specifically, the first terminal may be a drain, the second terminal may be a gate, and the third terminal may be a source. The second terminal of the field effect transistor Q1 may also be connected to the signal output terminal DR of the driving signal modulation module 400 through a parallel branch composed of a diode D1 and a resistor R1, and the third terminal of the field effect transistor Q1 is connected to the chip selection terminal CS of the driving signal modulation module 400. The anode of the diode D1 is connected to the second end of the field effect transistor Q1, and the cathode of the diode D1 is connected to the signal output end DR of the driving signal modulation module 400. The current sampling resistor may include at least a resistor R9 and a resistor R10 connected in parallel with each other.

Further, in some optional embodiments, the switching voltage driving module 300 further includes a third resistor unit, a capacitor C1 and a diode D4, which together form an RCD snubber circuit. The third resistance unit is connected in parallel with the capacitor C1 to form a second parallel circuit, one end of the second parallel circuit is connected to the cathode of the diode D4, the other end of the second parallel circuit is connected to the input module 100, and the anode of the diode D4 is connected to the second end of the primary coil and the switch unit 320, respectively. The third resistance unit may specifically include a resistor R5 and a resistor R6 connected in series with each other.

Generally, if no RCD absorption circuit is added, after the switching unit 320 is turned off, due to the energy storage characteristic of the inductor, the primary coil of the transforming unit 310 generates a forward voltage (i.e., the winding 2 is positive, and the winding 1 is negative), and the forward voltage is superimposed on the input voltage and applied to the switching unit 320, and the switching unit 320 may be damaged in a severe case. In the present application, the RCD absorption circuit is connected in parallel with the primary coil of the transformer unit 310, and part of the electric energy generated by the primary coil can be directly fed back to the main power supply after the switch unit 320 is turned off, so that the voltage generated by the leakage inductance of the transformer unit 310 and the input voltage are prevented from being superimposed on the switch unit 320, and the switch unit 320 is protected.

In some optional embodiments, the lamp slow-lighting control system may further include a power taking module 500, and the voltage transforming unit 310 further includes a second secondary coil, one end of the second secondary coil is grounded, and the other end of the second secondary coil is connected to the driving signal modulating module 400 through the power taking module 500. Specifically, the power-taking module 500 is connected to the power supply terminal VCC of the driving signal modulation module 400. It can be seen that after the input module 100 provides the start voltage for the driving signal modulation module 400, the driving signal modulation module 400 can also be powered through the transforming unit 310.

Optionally, the power taking module 500 may include a resistor R2, a diode D3, and a capacitor EC2, one end of the resistor R2 is connected to one end of the second secondary coil, the other end of the resistor R2 is connected to the anode of the diode D3, the cathode of the diode D3 is connected to one end of the driving signal modulation module 400 and one end of the capacitor EC2, and the other end of the capacitor EC2 is grounded. Specifically, the capacitor EC2 may be an electrolytic capacitor, and the cathode of the diode D3 and one end of the capacitor EC2 are both connected to the power supply terminal VCC of the driving signal modulation module 400.

In some embodiments of the present invention, the switching voltage driving module 300 further includes a diode D5, a resistor R8 and a capacitor EC3, the capacitor EC3 is connected in parallel with the resistor R8 to constitute a third parallel circuit, one end of the third parallel circuit is connected with the negative pole of the diode D5 and the positive pole of the load respectively, the other end of the third parallel circuit is connected with the second end of the first secondary coil and the negative pole of the load respectively, and the positive pole of the diode D5 is connected with the first end of the first secondary coil. Specifically, the capacitor EC3 may be an electrolytic capacitor. It can be seen that, based on the one-way conductivity of the diode D5, when the first secondary coil generates a negative voltage, no induced current is generated in the circuit and is output to the load, so that the circuit is protected in combination with the third series circuit.

All possible combinations of the technical features of the above embodiments may not be described for the sake of brevity, but should be considered as within the scope of the present disclosure as long as there is no contradiction between the combinations of the technical features.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A light fixture slow-lighting control system is characterized by comprising:

the input module (100) is used for being connected with a power supply;

a switching voltage driving module (300) connected with the input module (100) and a load to form at least part of a power supply loop;

a charging module (200) connected to the input module (100);

the driving signal modulation module (400) is respectively connected with the input module (100), the charging module (200) and the switching voltage driving module (300), and the driving signal modulation module (400) can form different driving signals according to the charging condition to drive the switching voltage driving module (300) to operate.

2. The lamp slow-lighting control system according to claim 1, wherein the charging module (200) comprises a capacitor EC4, a first resistor unit and a second resistor unit, the first resistor unit is connected in parallel with the capacitor EC4 to form a first parallel circuit, one end of the first parallel circuit is connected to the driving signal modulation module (400) and one end of the second resistor unit, the other end of the first parallel circuit is grounded, and the other end of the second resistor unit is connected to the input module (100).

3. The lamp slow-lighting control system according to claim 1, wherein the switching voltage driving module (300) comprises a switching unit (320) and a transforming unit (310), the switching unit (320) is respectively connected with the input module (100) and the transforming unit (310), the switching unit (320) is connected with the driving signal modulating module (400) to be turned on and off according to a driving signal, and the transforming unit (310) is connected with a load.

4. The system of claim 3, wherein the transforming unit (310) comprises a primary coil and a first secondary coil, a first end of the primary coil is connected to the input module (100), a second end of the primary coil is connected to the switching unit (320), a first end of the first secondary coil is connected to a positive pole of a load, a second end of the first secondary coil is connected to a negative pole of the load, and the first end of the first secondary coil and the second end of the primary coil are dotted terminals.

5. The lamp slow-lighting control system according to claim 4, wherein the switching voltage driving module (300) further comprises a third resistor unit, a capacitor C1 and a diode D4, the third resistor unit is connected in parallel with the capacitor C1 to form a second parallel circuit, one end of the second parallel circuit is connected to the cathode of the diode D4, the other end of the second parallel circuit is connected to the input module (100), and the anode of the diode D4 is connected to the second end of the primary coil and the switch unit (320), respectively.

6. The lamp slow-lighting control system according to claim 4, wherein the switch unit (320) comprises a field effect transistor, a first end of the field effect transistor is connected to the input module (100) and a second end of the primary coil, respectively, a second end of the field effect transistor is connected to the driving signal modulation module (400), a third end of the field effect transistor is grounded through a current sampling resistor, and a third end of the field effect transistor is connected to the driving signal modulation module (400).

7. The lamp soft-lighting control system according to claim 4, wherein the switching voltage driving module (300) further includes a diode D5, a resistor R8, and a capacitor EC3, the capacitor EC3 is connected in parallel with the resistor R8 to form a third parallel circuit, one end of the third parallel circuit is connected to the cathode of the diode D5 and the anode of the load respectively, the other end of the third parallel circuit is connected to the second end of the first secondary coil and the cathode of the load respectively, and the anode of the diode D5 is connected to the first end of the first secondary coil.

8. The lamp slow-lighting control system according to claim 4, further comprising a power-taking module (500), wherein the voltage transformation unit (310) further comprises a second secondary coil, one end of the second secondary coil is grounded, and the other end of the second secondary coil is connected to the driving signal modulation module (400) through the power-taking module (500).

9. The lamp slow-lighting control system according to claim 8, wherein the power-taking module (500) includes a resistor R2, a diode D3 and a capacitor EC2, one end of the resistor R2 is connected to one end of the second secondary coil, the other end of the resistor R2 is connected to an anode of the diode D3, a cathode of the diode D3 is connected to the driving signal modulation module (400) and one end of the capacitor EC2, respectively, and the other end of the capacitor EC2 is grounded.

10. A slow-lighting control system of a lamp as claimed in any one of claims 1 to 9, wherein the input module (100) includes a first input port, a second input port, and a rectifying unit, the first input port is used for connecting to a live wire of a power supply, the second input port is used for connecting to a neutral wire of the power supply, the rectifying unit has a first ac terminal, a second ac terminal, a first dc terminal, and a second dc terminal, the first ac terminal is connected to the first input port, the second ac terminal is connected to the second input port, the first dc terminal is grounded, and the second dc terminal is connected to the driving signal modulation module (400), the switching voltage driving module (300), and the charging module (200), respectively.