A novel surge protection circuit, driving power supply and lamp

Abstract

The utility model provides a novel anti -surge circuit, drive power supply and lamps and lanterns, and this drive power supply includes rectifier circuit, anti -surge circuit, first electric capacity, and anti -surge circuit includes first resistance, voltage sampling module, switch module and second switch tube, and switch module includes first switch tube and bias unit, voltage sampling module realizes the conduction and the close of control first switch tube through the control second switch tube, when the input end of rectifier circuit inserts the city power and starts, and first resistance both ends voltage is greater than or equal to the preset threshold value, and second switch tube conduction controls first switch tube cut-off, when the input end of rectifier circuit inserts the city power and starts to complete, and first resistance both ends voltage is less than the preset threshold value, and second switch tube closes, and bias unit makes first switch tube conduction to short circuit first resistance, and main circuit current enters first switch tube. The utility model has the characteristics of low loss and high efficiency on the basis of realizing the suppression surge current, and the cost is lower and the structure is simpler.

Description

Technical Field

[0001] This utility model relates to the field of driving power supply technology for lighting fixtures, specifically to a novel surge protection circuit, driving power supply, and lighting fixture. Background Technology

[0002] As society places increasingly higher demands on energy conservation, environmental protection, and stable power grid operation, the lighting industry has imposed more stringent requirements on the core performance indicators of driver power supplies. Specifically, driver power supplies must have lower inrush current, meaning the peak current generated at startup must be minimized to reduce the instantaneous impact and harmonic pollution on the power grid, preventing unexpected tripping events caused by excessively high instantaneous current, and ensuring the stability and safety of the power supply. Simultaneously, the energy conversion efficiency of the driver power supply itself is also increasingly demanding; the losses generated during the conversion of electrical energy into the stable operating conditions required by the lighting fixtures must be controlled to the lowest possible level.

[0003] See Figure 1 Before being connected to the mains power, the voltage across the aluminum electrolytic capacitor EC1 in a conventional drive power supply is 0V, meaning it has no charge. At the instant the mains power is connected, the voltage between the L and N lines starts from 0V and rises rapidly to the peak voltage of the mains power. This means that the mains power instantly charges the aluminum electrolytic capacitor EC1 through the rectifier bridge DB, which generates an extremely high surge current. Excessive surge current can have a significant impact on the power grid and may even lead to unexpected tripping events.

[0004] One existing solution is to add a thermistor with a negative temperature coefficient to the main circuit, using resistance to increase the impedance of the main circuit and reduce inrush current. See also Figure 2 The NTC1 thermistor with a negative temperature coefficient is connected in series in the main circuit, which can reduce the surge current. However, since the NTC1 thermistor will always generate losses, it will generate a large amount of loss, which will reduce the energy efficiency of the drive power supply.

[0005] Another existing solution involves adding a relay and control circuit to the main circuit, based on a thermistor with a negative temperature coefficient. After power-on, the control current does not flow through the thermistor, reducing losses and improving energy efficiency. See also Figure 3In addition to a negative temperature coefficient thermistor NTC2 in the main circuit, a relay and control circuit are also added. During power-on, relay K1 is inactive, and the thermistor NTC2 suppresses inrush current. After power-on, relay K1, under the control of the control circuit, closes to short-circuit the thermistor, ensuring that the main circuit current flows through relay K1 and not through the thermistor NTC2, thereby reducing losses and improving energy efficiency. However, this solution uses a more expensive relay, increasing costs; its mechanical switch suffers from short lifespan and large size; and the external control circuit is also relatively complex.

[0006] Another existing solution involves adding a resistor, a field-effect transistor (FET), a control circuit, and a matching circuit to the main circuit. During the power-on process, the FET is not conducting during the self-starting phase of the control circuit; current flows through the resistor and capacitor, protecting the circuit. After the control circuit self-starts during power-on, the FET conducts, allowing current to flow through it. However, this solution requires the control circuit to output a control signal to the matching circuit, which then provides the FET's turn-on voltage. This necessitates an additional control circuit, resulting in a complex overall circuit structure. Utility Model Content

[0007] The primary objective of this invention is to provide a novel surge-proof drive power supply that, while suppressing surge current, features low loss and high efficiency, and is also lower in cost and simpler in structure.

[0008] The second objective of this invention is to provide a novel surge protection circuit that can suppress surge current, and has a simple structure and lower cost.

[0009] The third objective of this invention is to provide a lighting fixture that includes the aforementioned novel surge-proof driving power supply. To achieve the aforementioned first objective, this utility model provides a novel surge-protected driving power supply, comprising: a rectifier circuit, a surge protection circuit, and a first capacitor. The surge protection circuit includes a first resistor, a voltage sampling module, a switching module, and a second switching transistor. The switching module includes a first switching transistor and a bias unit. The first terminal of the first capacitor is connected to the first output terminal of the rectifier circuit, and the second terminal of the first capacitor is connected to the first terminal of the first resistor. The second terminal of the first resistor is connected to the second output terminal of the rectifier circuit and grounded. The first terminal of the first switching transistor is connected to the first terminal of the first resistor, and the second terminal of the first switching transistor is connected to the first terminal of the first resistor. The controlled terminal of a first switching transistor is connected to the first terminal of a second switching transistor and a bias unit. The second terminal of the second switching transistor is grounded. The controlled terminal of the second switching transistor is connected to a voltage sampling module. The voltage sampling module is used to adjust the voltage of the controlled terminal of the second switching transistor according to the voltage across the first resistor. When the input terminal of the rectifier circuit is connected to the mains power and starts to start, the voltage across the first resistor is greater than or equal to a preset threshold, and the second switching transistor is turned on to control the first switching transistor to turn off. When the input terminal of the rectifier circuit is connected to the mains power and the start-up is completed, the voltage across the first resistor is less than the preset threshold, the second switching transistor is turned off, and the bias unit turns on the first switching transistor to short-circuit the first resistor.

[0010] As can be seen from the above scheme, this utility model controls the second switching transistor by setting a voltage sampling module to control the conduction and shutdown of the first switching transistor. Thus, when the power supply starts up after connecting to mains power, the first switching transistor is off, and the current in the main circuit flows through the first resistor, suppressing current spikes. After the power supply starts up, the bias unit turns the first switching transistor on to short-circuit the first resistor, causing the main circuit current to flow through the first switching transistor instead of the first resistor. Because the internal resistance of the first switching transistor is extremely low, losses are greatly reduced, and power supply heat generation is reduced, improving energy efficiency. The first switching transistor is a semiconductor device, without the limitation of switching cycles, the wear and tear problems of mechanical switches, or the arcing problems of mechanical switches, greatly improving reliability. Furthermore, this utility model does not require an additional control circuit, resulting in a simpler circuit structure and lower cost.

[0011] A further embodiment is that the voltage sampling module also includes a first Zener diode and a second resistor. The cathode of the first Zener diode is connected to the first terminal of the first resistor, the anode of the first Zener diode is connected to the first terminal of the second resistor and the controlled terminal of the second switching transistor, and the second terminal of the second resistor is grounded.

[0012] Therefore, the preset threshold can be adjusted by the voltage regulation value of the first Zener diode, making it convenient to adjust the preset threshold.

[0013] A further approach is to include a third resistor in the voltage sampling module, with the cathode of the first Zener diode connected to the first terminal of the first resistor via the third resistor.

[0014] Therefore, the third resistor serves as the pull-up power supply resistor for the controlled terminal of the first switching transistor, and also facilitates the adjustment of the preset threshold.

[0015] A further embodiment is that the bias unit includes a fourth resistor and a fifth resistor. The first end of the fourth resistor is connected to the first end of the first capacitor, the second end of the fourth resistor is connected to the first end of the fifth resistor and the control terminal of the first switching transistor, the first end of the fifth resistor is connected to the control terminal of the first switching transistor, and the second end of the fifth resistor is grounded.

[0016] Therefore, the fourth resistor serves as the pull-up power supply resistor for the first switching transistor to turn on, and the fifth resistor serves as the pull-down resistor for the first switching transistor, which can provide a reasonable bias for the first switching transistor.

[0017] A further option is that the bias unit also includes a second Zener diode, the second end of the fourth resistor is connected to the cathode of the second Zener diode, and the anode of the second Zener diode is grounded.

[0018] Therefore, by setting a second Zener diode, the voltage at the controlled terminal of the first switching transistor can be prevented from becoming too high and causing damage.

[0019] A further embodiment includes a second capacitor in the bias unit. The first end of the second capacitor is connected to the controlled terminal of the first switching transistor, and the second end of the second capacitor is grounded.

[0020] Therefore, it can be seen that the second capacitor, as a filter capacitor, can provide a stable voltage to the controlled terminal of the first switching transistor.

[0021] A further solution is a PFC circuit, which includes a first inductor, a first diode, a second diode, and a third switch. The first end of the first inductor is connected to the anode of the second diode and the first output terminal of the rectifier circuit, the second end of the first inductor is connected to the anode of the first diode, the cathodes of the first and second diodes are connected to the first terminal of the first capacitor, the first terminal of the third switch is connected to the second terminal of the first inductor and the anode of the first diode, the third terminal of the third switch is connected to the second terminal of the first capacitor, and the control terminal of the third switch receives an external control signal.

[0022] Therefore, it can be seen that by setting up a PFC circuit, the power factor of the drive power supply can be improved.

[0023] A further solution involves a sixth resistor and a third Zener diode. The first end of the sixth resistor is connected to the first end of the first capacitor, the second end of the sixth resistor is connected to the cathode of the third Zener diode, and the anode of the third Zener diode is connected to the control terminal of the second switching transistor.

[0024] Therefore, by setting a sixth resistor and a third Zener diode, it is possible to determine whether the first resistor is short-circuited after the drive power supply starts up, depending on the mains input. When the mains input is high, the main circuit current is smaller than when the mains input is low, and the heating of the first resistor is within a reasonable range. Thus, while ensuring the suppression effect of the first resistor on the current, the current harmonics at high voltage input are reduced, which is beneficial to meeting the harmonic standards of some regions (such as Europe).

[0025] To achieve the second objective mentioned above, this utility model provides a novel surge protection circuit, comprising: a first resistor, a voltage sampling module, a switching module, and a second switching transistor; the switching module includes the first switching transistor and a bias unit; a first terminal of the first resistor is connected to the second terminal of an external first capacitor, and the second terminal of the first resistor is grounded; a first terminal of the first switching transistor is connected to the first terminal of the first resistor, and a second terminal of the first switching transistor is connected to the first terminal of the first resistor; a controlled terminal of the first switching transistor is connected to the first terminal of the second switching transistor and the bias unit, and the second terminal of the second switching transistor is grounded; the controlled terminal of the second switching transistor is connected to the voltage sampling module, and the voltage sampling module is used to adjust the voltage of the controlled terminal of the second switching transistor according to the voltage across the first resistor; the voltage sampling module also includes a first Zener diode, The second resistor, the third resistor, the cathode of the first Zener diode is connected to the first end of the first resistor, the anode of the first Zener diode is connected to the first end of the second resistor and the controlled terminal of the second switch, the second end of the second resistor is grounded, and the cathode of the first Zener diode is connected to the first end of the first resistor via the third resistor; the bias unit includes a fourth resistor, a fifth resistor, a second Zener diode, and a second capacitor, the first end of the fourth resistor is connected to the first end of the first capacitor, the second end of the fourth resistor is connected to the first end of the fifth resistor and the control terminal of the first switch, the first end of the fifth resistor is connected to the control terminal of the first switch, the second end of the fifth resistor is grounded, the second end of the fourth resistor is connected to the cathode of the second Zener diode, the anode of the second Zener diode is grounded, the first end of the second capacitor is connected to the controlled terminal of the first switch, and the second end of the second capacitor is grounded.

[0026] As can be seen from the above solution, this utility model can suppress surge current while ensuring the suppression of surge current, and it does not require the setting of relays or controllers for control. It has a simple structure, lower cost, and wide range of applications.

[0027] To achieve the third objective mentioned above, this utility model provides a lamp, including a light-emitting device, which further includes the aforementioned novel surge-proof driving power supply, the driving power supply being connected to the light-emitting device. Attached Figure Description

[0028] Figure 1 This is a circuit diagram of a driving power supply in the prior art.

[0029] Figure 2 This is a circuit diagram of another type of driving power supply in the prior art.

[0030] Figure 3 This is a circuit diagram of another type of driving power supply in the existing technology.

[0031] Figure 4 This is a circuit diagram of the first embodiment of the novel surge-proof driving power supply of this utility model.

[0032] Figure 5 This is a circuit diagram of the second embodiment of the novel surge-proof driving power supply of this utility model.

[0033] Figure 6 This is a circuit diagram of the third embodiment of the novel surge-proof driving power supply of this utility model.

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0035] When the novel surge-proof drive power supply of this utility model starts up, there is a large surge current. This surge current flows into the thermistor. The voltage across the thermistor can be used to suppress the surge current during this process. After startup, the voltage across the thermistor can be used to control the switching transistor to short-circuit the thermistor, thereby reducing power loss after startup.

[0036] It should be noted that the following descriptions such as "first," "second," and "third" are used to distinguish similar things and do not imply any order of precedence.

[0037] First embodiment of a novel surge-protected drive power supply: See Figure 4 The driving power supply in this embodiment includes a rectifier circuit 11, a surge protection circuit 12, and a capacitor C1.

[0038] The rectifier circuit 11 includes a rectifier bridge DB1. The surge protection circuit 12 includes a voltage sampling module 121, a switching module 122, a first resistor R1, and a second switch Q2. The voltage sampling module 121 includes a first Zener diode ZD1, a second resistor R2, and a third resistor R3. The voltage switching module 122 includes a first switch Q1 and a bias unit, which includes a fourth resistor R4, a fifth resistor R5, a second Zener diode ZD2, and a second capacitor C2.

[0039] The first terminal of the first capacitor C1 is connected to the first output terminal of the rectifier circuit 11, which is also the "1" terminal of the rectifier bridge DB1. The second terminal of the first capacitor C1 is connected to the first terminal of the first resistor R1. The second terminal of the first resistor R1 is connected to the second output terminal of the rectifier circuit 11 and grounded, which is also the "2" terminal of the rectifier bridge DB1. The first terminal of the first switch Q1 is connected to the first terminal of the first resistor R1, and the second terminal of the first switch Q1 is also connected to the first terminal of the first resistor R1. The controlled terminal of the first switch Q1 is connected to the first terminal of the second switch Q2 and the bias unit. The second terminal of the second switch Q2 is connected to the second terminal of the second resistor R2 and grounded, and the controlled terminal of the second switch Q2 is connected to the voltage sampling module 121.

[0040] The cathode of the first Zener diode ZD1 is connected to the first terminal of the first resistor R1 through the third resistor R3. The anode of the first Zener diode ZD1 is connected to the first terminal of the second resistor R2 and the controlled terminal of the second switch Q2, and the second terminal of the second resistor R2 is grounded.

[0041] The first terminal of the fourth resistor R4 is connected to the first terminal of the first capacitor C1. The second terminal of the fourth resistor R4 is connected to the first terminal of the fifth resistor R5, the control terminal of the first switching transistor Q1, and the cathode of the second Zener diode ZD2. The first terminal of the fifth resistor R5 is connected to the control terminal of the first switching transistor Q1, and the second terminal of the fifth resistor R5 is grounded. The anode of the second Zener diode ZD2 is grounded. The first terminal of the second capacitor C2 is connected to the controlled terminal of the first switching transistor Q1, and the second terminal of the second capacitor C2 is grounded.

[0042] In this embodiment, the first capacitor C1 is an aluminum electrolytic capacitor, with its first terminal being the positive terminal and its second terminal being the negative terminal. The first resistor R1 is a negative temperature coefficient power thermistor, and its resistance value can be adjusted according to actual conditions. Increasing the resistance value of the first resistor R1 can improve the surge current suppression effect. The first switch Q1 is a high-voltage NMOS transistor, where its first terminal is the drain, its second terminal is the source, and its controlled terminal is the gate. The second switch Q2 is an NPN transistor, where its first terminal is the collector, its second terminal is the emitter, and its controlled terminal is the base. In other embodiments, other devices can be selected according to actual needs; for example, the second switch Q2 can be an NMOS transistor.

[0043] The voltage sampling module 121 is used to adjust the voltage of the controlled terminal of the second switch Q2 according to the voltage across the first resistor R1. When the input terminal of the rectifier circuit 11 is connected to the mains power and starts to start, the voltage across the first resistor R1 is greater than or equal to a preset threshold, the second switch Q2 is turned on and controls the first switch Q1 to be turned off, thereby suppressing the surge current through the first resistor; when the input terminal of the rectifier circuit 11 is connected to the mains power and the start-up is completed, the voltage across the first resistor R1 is less than the preset threshold, the second switch is turned off, the bias unit turns on the first switch to short-circuit the first resistor, since the current flows through the first switch instead of the first resistor, the energy consumption of the drive power supply can be reduced.

[0044] Specifically, at the instant that terminal "3" of rectifier bridge DB1 in rectifier circuit 11 is connected to the L line and terminal "4" of rectifier bridge DB1 is connected to the N line, i.e., at the instant of mains power connection, the mains voltage enters the first capacitor C1 and the first resistor R1 through rectifier bridge B1. The voltage across the first capacitor C1 rapidly rises to the peak value of the mains voltage, and the surge current flows through rectifier bridge DB1, the first capacitor C1, and the first resistor R1. The first resistor R1 suppresses the amplitude of the surge current and avoids the impact of the surge current. During the startup of the drive power supply after connection to mains power, the surge current flows through the first resistor. A voltage is generated across the first resistor that is phase-synchronized with the surge current and has a proportional amplification. The voltage sampling module 121 samples this voltage. When this voltage is higher than the voltage regulation value of the first Zener diode ZD1 in the voltage sampling module 121, the first Zener diode ZD1 is turned on. The voltage continues to rise, causing the base voltage of the second switch Q2 to reach 0.7V, thereby turning on the second switch Q2. The first switch Q2 pulls down the gate voltage of the first switch Q1, causing the first switch Q1 to turn off. All the surge current flows through the first resistor R1, and the first resistor R1 completely suppresses the amplitude of the surge current.

[0045] When the voltage across the first resistor reaches the peak voltage of the mains power, the drive power supply starts up, and the inrush current is reduced to an extremely low level. At this time, the voltage across the first resistor R1 is lower than the voltage regulation value of the first Zener diode ZD1, so the first Zener diode ZD1 is not conducting. The base voltage of the second switch Q2 is 0V, so the second switch Q2 is off, and therefore the second switch does not control the conduction and shutdown of the first switch Q1. The fourth resistor R4 in the bias unit pulls up the gate voltage of the first switch Q1 and stabilizes it to the voltage regulation value of the second Zener diode ZD2. After high-frequency filtering by the second capacitor C2, the first switch Q1 conducts. The conduction of the first switch Q1 short-circuits the first resistor R1, so that the main circuit current only flows through the conducting first switch Q1. Because the on-resistance of the first switch Q1 is extremely small, the loss is extremely low, resulting in less heat generation and improved efficiency of the drive power supply.

[0046] Second embodiment of the novel surge-protected drive power supply: The drive power supply in this embodiment is designed for full voltage input, that is, a rated input voltage of 100-240VAC.

[0047] This embodiment adds a third Zener diode ZD3 and a sixth resistor R6 to the first embodiment. The first terminal of the sixth resistor R6 is connected to the first terminal of the first capacitor C1, and the second terminal of the sixth resistor R6 is connected to the cathode of the third Zener diode ZD3. The anode of the third Zener diode ZD3 is connected to the control terminal of the second switching transistor Q2. The Zener voltage of the third Zener diode ZD3 can be adjusted according to specific circumstances.

[0048] During the startup of the drive power supply after connecting to the mains power, this embodiment is the same as the first embodiment described above, that is, the second switch Q2 controls the first switch Q1 to turn off, and the surge current is suppressed by the first resistor R1, which will not be described in detail here.

[0049] After the drive power supply starts up, there are two scenarios. The first scenario is when the mains input is lower than the set value (180VAC in this embodiment). For example, if the mains input is 100VAC in the first scenario, the third Zener diode ZD3 is not conducting, the second switch Q2 is not conducting, the first switch Q1 is conducting, and the first resistor R1 is short-circuited, improving the drive power supply efficiency. The second scenario is when the mains input is greater than or equal to the set value. For example, if the mains input is 220VAC in the second scenario, the third Zener diode ZD3 is conducting, causing the base voltage of the second switch Q2 to reach 0.7V. The second switch Q2 then conducts, pulling down the gate voltage of the first switch Q1, thus turning off the first switch Q1. The main circuit current flows through the first resistor R1 instead of through the first switch Q1. Since the input voltage is high (i.e. higher than the set value), the main circuit current is smaller than the main circuit current when the input voltage is low (i.e. lower than the set value). The heating of the first resistor R1 is within a reasonable range and acceptable. The connection of the first resistor R1 suppresses the current and reduces the current harmonics when the high voltage input is applied.

[0050] Third embodiment of the novel surge-protected drive power supply: See Figure 6 This embodiment adds a PFC circuit 13 based on the first embodiment described above.

[0051] The PFC circuit 13 includes a first inductor L1, a first diode D1, a second diode D2, and a third switch Q3.

[0052] The first end of the first inductor L1 is connected to the anode of the second diode D2 and the first output terminal of the rectifier circuit 11. The second end of the first inductor L1 is connected to the anode D1 of the first diode. The cathodes of the first diode D1 and the second diode D2 are connected to the first end of the first capacitor C1. The first terminal of the third switch Q3 is connected to the second end of the first inductor L1 and the anode of the first diode D1. The third terminal of the third switch Q3 is connected to the second end of the first capacitor C1. The control terminal of the third switch receives an external control signal.

[0053] In this embodiment, the third switch Q3 is an NMOS transistor; wherein, the first terminal of the third switch Q3 is the drain of the NMOS transistor, the second terminal of the third switch Q3 is the source of the NMOS transistor, and the controlled terminal of the third switch Q3 is the gate of the NMOS transistor; the control signal is a PWM signal; the first inductor L1 is a PFC inductor; the first diode D1 is a boost diode; and the second diode D2 is a surge protection freewheeling diode.

[0054] During the startup period of the drive power supply after connection to mains power, the PFC circuit 13 does not operate, and the rest is the same as in the first embodiment described above, so it will not be repeated here. After the drive power supply starts up, the first resistor R1 is short-circuited by the first switch Q1, the surge current disappears, and then the PFC circuit 13 operates. The operation of the PFC circuit 13 is controlled by receiving an external PWM signal. When the PWM signal is high, the third switch Q3 is turned on, and the first inductor L1 stores energy; when the PWM signal is low, the third switch Q3 is turned off, and the first inductor L1 generates an induced electromotive force. This induced electromotive force is superimposed on the voltage output by the rectifier bridge DB1 to charge the first capacitor C, thereby improving the power factor of the drive power supply. By setting the PFC circuit 13, low loss and high energy efficiency are achieved, and the drive power supply achieves a high PF value.

[0055] Lighting fixture examples: The lighting fixture of this embodiment includes a light-emitting device and a driving power supply of any of the above embodiments. The driving power supply is connected to the light-emitting device, which includes an LED chip. In the driving power supply of the above embodiments, those skilled in the art can also add functional modules according to actual needs. For example, a power conversion circuit can be connected between the Vin+ terminal and the Vin- terminal, and then connected to the light-emitting device through the power conversion circuit.

[0056] In summary, the novel surge protection circuit of this invention adopts all-semiconductor control, which is highly reliable, small in size, and improves the power density of the drive power supply. The drive power supply of this invention achieves low loss and high energy efficiency, reduces pollution and impact on the power grid, and can also further improve the surge current suppression effect by adjusting the resistance value of the first resistor.

[0057] Finally, it should be emphasized that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A novel surge-protected drive power supply, characterized in that, include: The circuit includes a rectifier circuit, a surge protection circuit, and a first capacitor. The surge protection circuit includes a first resistor, a voltage sampling module, a switching module, and a second switching transistor. The switching module includes a first switching transistor and a bias unit. The first terminal of the first capacitor is connected to the first output terminal of the rectifier circuit, the second terminal of the first capacitor is connected to the first terminal of the first resistor, the second terminal of the first resistor is connected to the second output terminal of the rectifier circuit and grounded; the first terminal of the first switch is connected to the first terminal of the first resistor, the second terminal of the first switch is connected to the first terminal of the first resistor, the controlled terminal of the first switch is connected to the first terminal of the second switch and the bias unit, the second terminal of the second switch is grounded, and the controlled terminal of the second switch is connected to the voltage sampling module. The voltage sampling module is used to adjust the voltage of the controlled terminal of the second switch according to the voltage across the first resistor. When the input terminal of the rectifier circuit is connected to the mains power and starts to start, the voltage across the first resistor is greater than or equal to a preset threshold, and the second switch is turned on to control the first switch to turn off; when the input terminal of the rectifier circuit is connected to the mains power and the start-up is completed, the voltage across the first resistor is less than the preset threshold, the second switch is turned off, and the bias unit turns on the first switch to short-circuit the first resistor.

2. The novel surge-protected drive power supply as described in claim 1, characterized in that: The voltage sampling module further includes a first Zener diode and a second resistor. The cathode of the first Zener diode is connected to the first terminal of the first resistor, the anode of the first Zener diode is connected to the first terminal of the second resistor and the controlled terminal of the second switching transistor, and the second terminal of the second resistor is grounded.

3. The novel surge-protected drive power supply as described in claim 2, characterized in that: The voltage sampling module further includes a third resistor, and the cathode of the first Zener diode is connected to the first end of the first resistor via the third resistor.

4. The novel surge-protected drive power supply as described in claim 1, characterized in that: The bias unit includes a fourth resistor and a fifth resistor. The first end of the fourth resistor is connected to the first end of the first capacitor. The second end of the fourth resistor is connected to the first end of the fifth resistor and the control terminal of the first switching transistor. The first end of the fifth resistor is connected to the control terminal of the first switching transistor. The second end of the fifth resistor is grounded.

5. The novel surge-protected drive power supply as described in claim 4, characterized in that: The bias unit further includes a second Zener diode, the second end of the fourth resistor is connected to the cathode of the second Zener diode, and the anode of the second Zener diode is grounded.

6. The novel surge-protected drive power supply as described in claim 1, characterized in that: The bias unit further includes a second capacitor, the first end of which is connected to the controlled terminal of the first switching transistor, and the second end of which is grounded.

7. The novel surge-protected drive power supply as described in claim 1, characterized in that, Also includes: The PFC circuit includes a first inductor, a first diode, a second diode, and a third switching transistor. The first end of the first inductor is connected to the anode of the second diode and the first output terminal of the rectifier circuit. The second end of the first inductor is connected to the anode of the first diode. The cathodes of the first diode and the second diode are connected to the first end of the first capacitor. The first terminal of the third switch is connected to the second end of the first inductor and the anode of the first diode. The third terminal of the third switch is connected to the second end of the first capacitor. The control terminal of the third switch receives an external control signal.

8. The novel surge-protected drive power supply as described in any one of claims 1 to 7, characterized in that, Also includes: A sixth resistor and a third Zener diode are provided. The first end of the sixth resistor is connected to the first end of the first capacitor, the second end of the sixth resistor is connected to the cathode of the third Zener diode, and the anode of the third Zener diode is connected to the control terminal of the second switching transistor.

9. A novel surge protection circuit, characterized in that, include: The surge protection circuit includes a first resistor, a voltage sampling module, a switching module, and a second switching transistor. The switching module includes a first switching transistor and a bias unit. The first end of the first resistor is connected to the second end of an external first capacitor, the second end of the first resistor is grounded, the first terminal of the first switch is connected to the first end of the first resistor, the second terminal of the first switch is connected to the first end of the first resistor, the controlled terminal of the first switch is connected to the first terminal of the second switch and the bias unit, the second terminal of the second switch is grounded, and the controlled terminal of the second switch is connected to the voltage sampling module. The voltage sampling module is used to adjust the voltage of the controlled terminal of the second switch according to the voltage across the first resistor. The voltage sampling module further includes a first Zener diode, a second resistor, and a third resistor. The cathode of the first Zener diode is connected to the first end of the first resistor, the anode of the first Zener diode is connected to the first end of the second resistor and the controlled terminal of the second switching transistor, the second end of the second resistor is grounded, and the cathode of the first Zener diode is connected to the first end of the first resistor via the third resistor. The bias unit includes a fourth resistor, a fifth resistor, a second Zener diode, and a second capacitor. The first end of the fourth resistor is connected to the first end of the first capacitor. The second end of the fourth resistor is connected to the first end of the fifth resistor and the control terminal of the first switching transistor. The first end of the fifth resistor is connected to the control terminal of the first switching transistor. The second end of the fifth resistor is grounded. The second end of the fourth resistor is connected to the cathode of the second Zener diode. The anode of the second Zener diode is grounded. The first end of the second capacitor is connected to the controlled terminal of the first switching transistor. The second end of the second capacitor is grounded.

10. A lamp, comprising a light-emitting device, characterized in that, Also includes: The novel surge-protected driving power supply as described in any one of claims 1 to 8, wherein the driving power supply is connected to the light-emitting device.

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