Lightning protection detection and protection circuit and electric energy conversion device

Abstract

The utility model discloses a lightning protection detection and protection circuit and an electric energy conversion device, and belongs to the technical field of lightning protection, the lightning protection detection and protection circuit comprises a first capacitor, a first resistor, a first diode and a first comparator, the first end of the first capacitor is connected with the positive end of a bus, and the second end of the first capacitor is connected with the first end of the first resistor; the second end of the first resistor is grounded, the second end of the first capacitor is connected with the anode of the first diode, the cathode of the first diode is connected with a power supply, the anode of the first diode is connected with the first input end of the first comparator, and the second input end of the first comparator is grounded through reference voltage. According to the lightning protection detection and protection circuit and the electric energy conversion device, lightning stroke can be detected before bus overvoltage is formed by lightning stroke, and rapid, timely and effective protection is formed.

Description

Technical Field

[0001] The utility model relates to the technical field of lightning protection, and in particular to a lightning protection detection and protection circuit and an electric energy conversion device. Background Art

[0002] When dealing with lightning strikes, the following two devices are commonly used to suppress differential mode lightning strike voltages. One is to connect a large-capacity electrolytic capacitor (BULK capacitor) in parallel to the busbar, and the other is to connect a varistor (MOV) or a transient suppression diode (TVS) and other devices in parallel to the busbar to absorb lightning strike energy to suppress the voltage impact caused by lightning strikes. Figure 1 As shown, the AC voltage u AC , rectifier circuit 1, and power circuit 2 are connected in parallel in sequence, and control circuit 3 controls the on and off of the switch in power circuit 2. In order to suppress the lightning voltage, a transient suppression diode TVS and an electrolytic capacitor C are connected in parallel on the bus between the rectifier circuit 1 and the power circuit 2. b .

[0003] However, in some applications with high size requirements such as ultra-small adapters or module power supplies, electrolytic capacitors, varistors, transient suppression diodes, etc. are subject to large size restrictions, which often leads to excessive overshoot of the bus voltage at a higher slope during lightning strikes. At this time, the device voltage and current stress of the power tube or the subsequent power circuit are often difficult to meet the derating requirements, and there is a risk of failure. The conventional way to deal with this problem is to set up an overvoltage protection (OVP) circuit and other protection methods to shut down the power circuit after the voltage of the electrolytic capacitor exceeds the normal voltage. However, when the voltage of the electrolytic capacitor is small and the lightning voltage is high, such as above 1.2kV, the bus voltage V bus The rising slope can often reach more than 50V / us, but the overvoltage protection circuit needs to act after the voltage of the electrolytic capacitor is over-voltage, and there is a delay in the protection action time, which often makes it difficult to achieve timely protection. Utility Model Content

[0004] The utility model aims to provide a lightning protection detection and protection circuit and an electric energy conversion device.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the utility model is:

[0006] A lightning protection detection and protection circuit is connected to a bus, and includes a first capacitor, a first resistor, a first diode and a first comparator. The first end of the first capacitor is connected to the positive end of the bus, the second end of the first capacitor is connected to the first end of the first resistor, the second end of the first resistor is grounded, the second end of the first capacitor is connected to the anode of the first diode, the cathode of the first diode is connected to a power supply, the anode of the first diode is connected to the first input end of the first comparator, and the second input end of the first comparator is grounded through a reference voltage.

[0007] The above-mentioned lightning protection detection and protection circuit also includes a second diode, the second end of the first capacitor is connected to the anode of the second diode, and the cathode of the second diode is connected to the anode of the first diode.

[0008] The above-mentioned lightning protection detection and protection circuit further includes a filtering module, and the filtering module is connected between the anode of the first diode and the first input terminal of the first comparator.

[0009] In a specific embodiment, the filtering module includes a second resistor and a second capacitor, the first end of the second resistor is connected to the anode of the first diode, the second end of the second resistor is connected to the first input end of the first comparator, and the second end of the second resistor is grounded through the second capacitor.

[0010] The utility model also provides an electric energy conversion device, including a lightning protection detection and protection circuit as described above, and also including a rectifier circuit, a power circuit and a control circuit, wherein an AC voltage is connected to the input of the rectifier circuit, the output of the rectifier circuit is connected to the power circuit via a bus, and the control circuit is connected to the power circuit.

[0011] The above-mentioned electric energy conversion device also includes a transient suppression diode, which is connected in parallel between the busbars.

[0012] The above-mentioned electric energy conversion device also includes an electrolytic capacitor, which is connected in parallel between the busbars.

[0013] In a specific embodiment, the rectifier module includes a third diode, a fourth diode, a fifth diode and a sixth diode, the first end of the AC voltage is connected to the cathode of the third diode and the anode of the sixth diode, the anode of the third diode is connected to the anode of the fourth diode, the cathode of the fourth diode and the anode of the fifth diode are connected to the second end of the AC voltage, the cathode of the fifth diode is connected to the cathode of the sixth diode, and the cathode of the sixth diode and the anode of the fourth diode are connected in parallel with the power circuit.

[0014] Beneficial effect: The utility model provides a lightning protection detection and protection circuit and electric energy conversion device, which can detect a lightning strike before it causes bus overvoltage, shut down the power circuit earlier, avoid the risk of device overvoltage and overcurrent caused by lightning strike, and form fast, timely and effective protection; and has the characteristics of small size, fast response, low power consumption, simple and effective, and is particularly suitable for applications such as adapters and module power supplies.

[0015] In order to make the above features and advantages of the utility model more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of an existing lightning protection circuit.

[0017] Figure 2 The utility model is a schematic diagram of a specific embodiment of a lightning protection detection and protection circuit. DETAILED DESCRIPTION

[0018] In order to make the purpose and technical solution of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] Figure 2 This is a schematic diagram of a specific embodiment of a lightning protection detection and protection circuit of the utility model. Figure 2 As shown, in this specific embodiment, the rectifier module 1 includes a diode D3, a diode D4, a diode D5 and a diode D6, and the AC voltage u AC The first end of the diode D3 is connected to the cathode of the diode D3 and the anode of the diode D6, the anode of the diode D3 is connected to the anode of the diode D4, and the cathode of the diode D4 and the anode of the diode D5 are connected to an AC voltage u AC The second end of the diode D5 is connected to the cathode of the diode D6, and the cathode of the diode D6 and the anode of the diode D4 are connected in parallel to the power circuit 2.

[0020] More specifically, the cathode of the diode D6 is the positive end of the busbar, the anode of the diode D4 is the negative end of the busbar, the transient suppression diode TVS is connected in parallel between the busbars, and the electrolytic capacitor C b Connected in parallel between busbars.

[0021] The utility model discloses a lightning protection detection and protection circuit 4, which includes a capacitor C1, a resistor R1, a diode D1, a diode D2 and a comparator A1. The first end of the capacitor C1 is connected to the positive end of the busbar, the second end of the capacitor C1 is connected to the first end of the resistor R1, the second end of the resistor R1 is grounded, the second end of the capacitor C1 is connected to the anode of the diode D2, the cathode of the diode D2 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to the power supply VCC, the anode of the diode D1 is connected to the first input end of the comparator A1, and the second input end of the comparator A1 is connected to the reference voltage V ref Ground.

[0022] More specifically, the function of the capacitor C1 and the resistor R1 is to detect the bus voltage V bus The slope dV bus / dt and outputs symbolic slope dV bus / dt voltage V S , where the voltage V S With bus voltage V bus The slope dV bus / dt increases. The comparator A1 converts the voltage V S With reference voltage V ref Comparison, when the voltage V S Exceeds the reference voltage V ref When , the comparator A1 flips and outputs a signal to the control circuit 3, and the control circuit 3 works to turn off the power circuit 2, thereby realizing the protection function.

[0023] More specifically, the voltage V can be adjusted by adjusting the values ​​of the capacitor C1 and the resistor R1. S The value and the corresponding delay.

[0024] More specifically, the diode D2 is used for rectification and to prevent negative voltage from occurring at the front end.

[0025] More specifically, the role of the diode D1 is to prevent the bus voltage V bus The slope dV bus When / dt is too large, the voltage V sampled by the capacitor C1 and the resistor R1 S If it is too large, the subsequent comparator will be damaged.

[0026] Furthermore, the utility model lightning protection detection and protection circuit 4 also includes a filter module 41 for filtering interference, and the filter module 41 is connected between the anode of the diode D1 and the first input terminal of the comparator A1. In this specific embodiment, the filter module 41 includes a resistor R2 and a capacitor C2, the first end of the resistor R2 is connected to the anode of the diode D1, the second end of the resistor R2 is connected to the first input terminal of the comparator A1, and the second end of the resistor R2 is grounded through the capacitor C2.

[0027] The utility model also provides an electric energy conversion device, including the lightning protection detection and protection circuit 4, the rectifier circuit 1, the power circuit 2 and the control circuit 3, the AC voltage u AC The input of the rectifier circuit 1 is connected, the output of the rectifier circuit 1 is connected to the power circuit 2 through a bus, the control circuit 3 is connected to the power circuit 2, the control circuit 3 controls the on and off of the switch in the power circuit 2, and the lightning protection detection and protection circuit 4 is connected to the bus.

[0028] Furthermore, the electric energy conversion device also includes a transient suppression diode TVS, and the transient suppression diode TVS is connected in parallel between the busbars.

[0029] Furthermore, the electric energy conversion device also includes an electrolytic capacitor C b , the electrolytic capacitor C b Connected in parallel between busbars.

[0030] Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims

1. A lightning protection detection and protection circuit, characterized in that: The lightning protection detection and protection circuit is connected to a bus, and includes a first capacitor, a first resistor, a first diode and a first comparator. The first end of the first capacitor is connected to the positive end of the bus, the second end of the first capacitor is connected to the first end of the first resistor, the second end of the first resistor is grounded, the second end of the first capacitor is connected to the anode of the first diode, the cathode of the first diode is connected to a power supply, the anode of the first diode is connected to the first input end of the first comparator, and the second input end of the first comparator is grounded through a reference voltage.

2. A lightning protection detection and protection circuit as claimed in claim 1, characterized in that: A second diode is also included, the second end of the first capacitor is connected to the anode of the second diode, and the cathode of the second diode is connected to the anode of the first diode.

3. A lightning protection detection and protection circuit as claimed in claim 2, characterized in that: The device further comprises a filtering module connected between the anode of the first diode and the first input terminal of the first comparator.

4. A lightning protection detection and protection circuit as claimed in claim 3, characterized in that: The filtering module includes a second resistor and a second capacitor, a first end of the second resistor is connected to the anode of the first diode, a second end of the second resistor is connected to the first input end of the first comparator, and a second end of the second resistor is grounded through the second capacitor.

5. An electric energy conversion device, characterized in that: It comprises a lightning protection detection and protection circuit as described in any one of claims 1 to 4, and also comprises a rectifier circuit, a power circuit and a control circuit, wherein an AC voltage is connected to the input of the rectifier circuit, an output of the rectifier circuit is connected to the power circuit via a bus, and the control circuit is connected to the power circuit.

6. An electric energy conversion device as claimed in claim 5, characterized in that: A transient suppression diode is also included, and the transient suppression diode is connected in parallel between the bus bars.

7. An electric energy conversion device as claimed in claim 5, characterized in that: It also includes an electrolytic capacitor, which is connected in parallel between the busbars.

8. An electric energy conversion device as claimed in claim 5, characterized in that: The rectifier circuit includes a third diode, a fourth diode, a fifth diode and a sixth diode, the first end of the AC voltage is connected to the cathode of the third diode and the anode of the sixth diode, the anode of the third diode is connected to the anode of the fourth diode, the cathode of the fourth diode and the anode of the fifth diode are connected to the second end of the AC voltage, the cathode of the fifth diode is connected to the cathode of the sixth diode, and the cathode of the sixth diode and the anode of the fourth diode are connected in parallel with the power circuit.

Images