Reusable high-voltage rapid electronic fuse

Abstract

The invention relates to a reusable high-voltage rapid electronic fuse which comprises a first power tube IGBT, a second power tube IGBT, a first fly-wheel diode, a second fly-wheel diode, a first RCD absorption loop and a second RCD absorption loop, the first power tube IGBT and the second power tube IGBT are reversely connected in series, the first fly-wheel diode is connected with the first power tube IGBT in parallel, and the second fly-wheel diode is connected with the second power tube IGBT in parallel. The second fly-wheel diode is connected with the second power tube IGBT in parallel, the first RCD absorption loop is connected with the first power tube IGBT in parallel, and the second RCD absorption loop is connected with the second power tube IGBT in parallel. The double-RCD absorption circuit has the advantages that the double-RCD absorption circuit is used for suppressing the turn-off peak voltage at the turn-off moment of a power tube IGBT, a traditional RC absorption circuit is poor in overvoltage suppression effect when short-circuit current flows through an absorption resistor at the turn-off moment of the IGBT, and the absorption circuit ingeniously utilizes a fly-wheel diode integrated in the IGBT as an RCD absorption diode at the turn-off moment of the IGBT, so that the over-voltage suppression effect is not good. The complexity of equipment is reduced while the absorption effect is improved, and the cost of the equipment is reduced.

Description

Technical Field

[0001] The invention relates to a reusable high-voltage fast electronic fuse. Background Art

[0002] Fuses are important protective components for electrical equipment. When a short circuit occurs in an electrical equipment, the fuse element can quickly blow, thereby disconnecting the short circuit current and providing short circuit protection for the equipment. Conventional fuses use the thermal effect generated by the short circuit current in the fuse element to cause the fuse element to melt and disconnect the short circuit current. Since conventional fuses disconnect the short circuit current mechanically by the fuse element melting, their breaking speed is slow and they cannot be reused. In recent years, higher requirements have been placed on the breaking speed and breaking voltage of fuses. Traditional fusible fuses have bottlenecks in breaking speed and breaking voltage (ms-level breaking speed) due to the mechanical breaking method, and cannot meet the requirements of certain occasions. Summary of the invention

[0003] The purpose of the present invention is to provide a reusable high-voltage fast electronic fuse that can quickly cut off short-circuit current and can be used in AC circuits or DC circuits. Since all electronic devices are used, the fuse can be used repeatedly, saving the use cost.

[0004] To achieve the above object, the present invention is implemented through the following technical solutions:

[0005] A reusable high-voltage fast electronic fuse comprises a power tube IGBT 1, a power tube IGBT 2, a freewheeling diode 1, a freewheeling diode 2, an RCD absorption circuit 1, and an RCD absorption circuit 2. The power tube IGBT 1 and the power tube IGBT 2 are connected in reverse series, the freewheeling diode 1 is connected in parallel with the power tube IGBT 1, the freewheeling diode 2 is connected in parallel with the power tube IGBT 2, the RCD absorption circuit 1 is connected in parallel with the power tube IGBT 1, and the RCD absorption circuit 2 is connected in parallel with the power tube IGBT 2.

[0006] The RCD absorption circuit 1 includes an absorption capacitor 1 and an absorption resistor 1 connected in parallel, and the RCD absorption circuit 2 includes an absorption capacitor 2 and an absorption resistor 2 connected in parallel.

[0007] Both the power tube IGBT 1 and the power tube IGBT 2 are insulated gate bipolar power tubes.

[0008] It also includes a current transformer and a main circuit inductor. One end of the power tube IGBT 1 is provided with a current transformer, which is used to detect the current in the main circuit of the high-voltage fast electronic fuse. The other end of the power tube IGBT 2 is connected to the main circuit inductor.

[0009] The first freewheeling diode is integrated in the first power tube IGBT, and the second freewheeling diode is integrated in the second power tube IGBT.

[0010] A control method for a reusable high-voltage fast electronic fuse is provided. When a current sensor detects that the current in the main circuit of the high-voltage fast electronic fuse exceeds a set value, the power tube IGBT 1 and the power tube IGBT 2 are locked. The content is as follows:

[0011] When the fault current flows from right to left at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor one through the freewheeling diode two. When the voltage across the absorption capacitor one reaches the peak value, the absorption capacitor one reversely charges the main circuit inductance through the absorption resistor two.

[0012] When the fault current flows from left to right at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor 2 through the freewheeling diode pair. When the voltage across the absorption capacitor 2 reaches the peak value, the absorption capacitor 2 reversely charges the main circuit inductance through the absorption resistor pair.

[0013] The freewheeling diode 1 is used as the absorption diode of the RCD absorption circuit 1, and the freewheeling diode 2 is used as the absorption diode of the RCD absorption circuit 2;

[0014] Absorption capacitor 1 is used to absorb the turn-off voltage generated by the instantaneous main circuit inductance of power tube IGBT 1, and absorption capacitor 2 is used to absorb the turn-off voltage generated by the instantaneous main circuit inductance of power tube IGBT 2;

[0015] Absorption resistor 1 is used for damping the oscillating current formed between the capacitor and the main circuit inductance, and absorption resistor 2 is used for damping the oscillating current formed between the capacitor and the main circuit inductance.

[0016] A computer device comprises: at least one processor, and a memory connected to the at least one processor in communication, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the control method of any reusable high-voltage fast electronic fuse in claims 5-6.

[0017] A computer-readable storage medium storing computer instructions for causing the computer to execute the control method of any reusable high-voltage fast electronic fuse in claims 6-7.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The fuse of the present invention adopts high-voltage and large-capacity IGBT as a breaking device, which can disconnect the short-circuit current of the main circuit within a few microseconds. Since the traditional mechanical fuse-type fusing method is abandoned and the IGBT electronic breaking method is adopted, it can be used repeatedly after the equipment is powered on again;

[0020] 2. A double RCD absorption circuit, namely RCD absorption circuit one and RCD absorption circuit two, is used to suppress the turn-off peak voltage at the moment when the power tube IGBT is turned off. In the traditional RC absorption circuit, at the moment when the IGBT is turned off, the short-circuit current flows through the absorption resistor, and the overvoltage suppression effect is poor. The absorption circuit of the present invention cleverly uses the freewheeling diode integrated inside the IGBT as the RCD absorption diode at the moment when the IGBT is turned off, which reduces the complexity of the equipment and reduces the equipment cost while improving the absorption effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the principle of a reusable high-voltage fast electronic fuse;

[0022] Figure 2 It is a current flow diagram of a reusable high-voltage fast electronic fuse during normal operation;

[0023] Figure 3 This is a current flow diagram of a reusable high-voltage fast electronic fuse when the fault current is turned off from left to right;

[0024] Figure 4 This is a current flow diagram of a reusable high-voltage fast electronic fuse when the fault current is turned off from right to left;

[0025] Figure 5 Schematic diagram of the turn-off voltage waveform of a reusable high-voltage fast electronic fuse. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0027] A reusable high-voltage fast electronic fuse can cut off AC or DC short-circuit current, has a fast cutting speed, is reusable, and has a simple circuit structure. The main circuit of the high-voltage fast electronic fuse includes a reverse series power tube, a dual RCD absorption circuit, and a Hall current sensor; the reverse series power tube includes a high-voltage insulated gate bipolar power tube IGBT 1 and an insulated gate bipolar power tube IGBT 2, the IGBT 1 has an internal integrated freewheeling diode 1, and the power tube IGBT 2 has an internal integrated freewheeling diode 2; when the current in the main circuit of the high-voltage fast electronic fuse is within a set value, the IGBT 1 and the IGBT 2 are triggered , so that IGBT 1 and IGBT 2 remain in the on state; when the Hall current sensor detects a short-circuit fault current, the current in the main circuit of the high-voltage fast electronic fuse exceeds the set value, locking IGBT 1 and IGBT 2. Since IGBT 1 and IGBT 2 are connected in reverse series, they can break the bidirectional fault current, thereby disconnecting the short-circuit current. The IGBT element is used as the fault current cutting element. Therefore, compared with the traditional fuse, the present invention has the characteristic of being able to be used repeatedly and has the characteristic of high-speed shutdown. The IGBT element of the corresponding voltage level and current level can be selected according to the working current and working voltage of the system.

[0028] If the short-circuit loop contains an inductive load (including loop stray inductance), a shutdown overvoltage will be generated at the shutdown point when the fault current is quickly cut off. Therefore, it is necessary to add absorption loops at both ends of IGBT 1 and IGBT 2, namely RCD absorption loop 1 and RCD absorption loop 2. Absorption resistors and absorption capacitors are connected in parallel at both ends of IGBT 1 and IGBT 2, respectively, and a bidirectional RCD absorption loop is formed together with the freewheeling diodes integrated in IGBT 1 and IGBT 2. The bidirectional RCD absorption loop has a better absorption effect than the ordinary RC system loop and is more suitable for the shutdown absorption of large short-circuit currents. At the same time, the freewheeling diode integrated in the IGBT itself is used as the absorption diode, which not only improves the absorption effect, but also simplifies the circuit and saves costs. In addition, the circuit topology of the present invention directly connects the absorption capacitor in parallel at both ends of the switching device, which can minimize the stray inductance of the absorption loop and the switching device, thereby reducing the shutdown overvoltage generated by this part of the inductance.

[0029] The following examples are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.

[0030] [Example 1]

[0031] See Figure 1The main circuit of a reusable high-voltage fast electronic fuse is composed of an IGBT 1 and its freewheeling diode 3, an IGBT 2 and its freewheeling diode 4, an absorption capacitor 5, an absorption capacitor 6, an absorption resistor 7, an absorption resistor 8, and a Hall current transformer 9. The IGBT 1 and the IGBT 2 are connected in reverse series and are used to turn on / off the main circuit. When the main circuit is working normally, the two IGBTs are turned on. The Hall current transformer 9 monitors the current of the main circuit. When a short circuit fault occurs in the main circuit, the two IGBTs are locked. The IGBT 1 and the IGBT 2 are respectively used to turn off the fault current in two directions to form a bidirectional blocking circuit. When the main circuit is working normally, the freewheeling diode 3 and the freewheeling diode 4 serve as the freewheeling diodes of the corresponding IGBTs to form the flow path of the normal working current. When a short circuit fault occurs in the main circuit, they serve as the RCD absorption diodes of the IGBT 1 and the IGBT 2. The absorption capacitors 5 and 6 are used to absorb the turn-off voltage generated by the main circuit inductance at the moment when the IGBT is turned off. The absorption resistors 7 and 8 are used to damp the oscillating current formed between the absorption capacitor and the main circuit inductance.

[0032] See Figure 2 When the main circuit works normally, the reusable high-voltage fast electronic fuse is equivalent to a wire. At this time, IGBT 1 and IGBT 2 are triggered to turn on, and IGBT 1 and freewheeling diode 4 form a flow path for current I1 from right to left, and IGBT 2 and freewheeling diode 3 form a flow path for current I2 from left to right.

[0033] See Figure 3 When a short circuit occurs in the main circuit, a reusable high-voltage fast electronic fuse is used to act as a fuse. Since the IGBT device is used as a breaking device, the speed of breaking the short-circuit current is much higher than the melting speed of the traditional fusible fuse, and it has the characteristic of being reusable. When the fault current flows from right to left at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor 5 through the freewheeling diode 4, that is, the current I3. The absorption capacitor 5 is connected in parallel with the IGBT 1 to suppress the overvoltage generated at the moment of IGBT 1 shutdown. When the voltage across the absorption capacitor 5 reaches a peak value, the absorption capacitor 5 reversely charges the main circuit inductance 10 through the absorption resistor 8, that is, the current I4. The absorption resistor 8 provides a damping effect for the oscillating current and quickly exhausts the oscillation energy.

[0034] See Figure 4When the fault current flows from left to right at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor 6 through the freewheeling diode 3, that is, the current I5. The absorption capacitor 6 is connected in parallel with the IGBT 2 to suppress the overvoltage generated at the moment of shutdown of the IGBT 2. When the voltage across the absorption capacitor 6 reaches the peak value, the absorption capacitor 6 reversely charges the main circuit inductance 10 through the absorption resistor 7, that is, the current I6. The absorption resistor 7 provides a damping effect for the oscillating current and quickly consumes the oscillation energy.

[0035] See Figure 5 , is the voltage waveform diagram at the moment of IGBT shut-off. The first peak V1 is the instantaneous overvoltage caused by the stray inductance between the absorption capacitor and the IGBT at the moment of IGBT shut-off. Since the absorption capacitor and the IGBT are directly connected in parallel, there are fewer circuit components, which can minimize the stray inductance (the first shut-off peak V1). The second peak V2 is the instantaneous overvoltage induced by the main circuit inductance. Since the RCD absorption circuit is adopted, the shutdown current charges the absorption capacitor through the diode during the overvoltage absorption stage (the shutdown current does not leave the absorption resistor), so the absorption effect is much better than the conventional RC absorption circuit. At the same time, the present invention cleverly uses the IGBT freewheeling diode to serve as the RCD absorption diode during the IGBT shutdown period. Therefore, without increasing the cost and structural complexity, the absorption effect of the absorption circuit is greatly improved, and the overvoltage at the moment of short-circuit current cut-off is effectively suppressed. In addition, due to the use of the RCD absorption circuit, the present invention (absorption resistor) can quickly damp the system oscillation current during the period of cutting off the fault short-circuit current, and can quickly reach a stable state during the shutdown period, thereby improving the speed of the equipment cutting off the fault current.

Claims

1. A reusable high-voltage fast-acting electronic fuse, characterized in that: It includes power tube IGBT 1, power tube IGBT 2, freewheeling diode 1, freewheeling diode 2, RCD absorption circuit 1, and RCD absorption circuit 2. Power tube IGBT 1 and power tube IGBT 2 are connected in reverse series, freewheeling diode 1 is connected in parallel with power tube IGBT 1, freewheeling diode 2 is connected in parallel with power tube IGBT 2, RCD absorption circuit 1 is connected in parallel with power tube IGBT 1, and RCD absorption circuit 2 is connected in parallel with power tube IGBT 2.

2. A reusable high-voltage fast-acting electronic fuse according to claim 1, characterized in that: The RCD absorption circuit 1 includes an absorption capacitor 1 and an absorption resistor 1 connected in parallel, and the RCD absorption circuit 2 includes an absorption capacitor 2 and an absorption resistor 2 connected in parallel.

3. A reusable high-voltage fast-acting electronic fuse according to claim 1, characterized in that: It also includes a current transformer and a main circuit inductor. One end of the power tube IGBT 1 is provided with a current transformer, which is used to detect the current in the main circuit of the high-voltage fast electronic fuse. The other end of the power tube IGBT 2 is connected to the main circuit inductor.

4. A control method for a reusable high-voltage fast electronic fuse according to any one of claims 1 to 3, characterized in that: When the current sensor detects that the current in the main circuit of the high-voltage fast electronic fuse exceeds the set value, the power tube IGBT 1 and the power tube IGBT 2 are locked. The contents are as follows: When the fault current flows from right to left at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor one through the freewheeling diode two. When the voltage across the absorption capacitor one reaches the peak value, the absorption capacitor one reversely charges the main circuit inductance through the absorption resistor two. When the fault current flows from left to right at the moment of shutdown, the residual current of the main circuit inductance charges the absorption capacitor 2 through the freewheeling diode pair. When the voltage across the absorption capacitor 2 reaches the peak value, the absorption capacitor 2 reversely charges the main circuit inductance through the absorption resistor pair.

5. The control method of a reusable high-voltage fast electronic fuse according to claim 4, characterized in that: The freewheeling diode 1 is used as the absorption diode of the RCD absorption circuit 1, and the freewheeling diode 2 is used as the absorption diode of the RCD absorption circuit 2; Absorption capacitor 1 is used to absorb the turn-off voltage generated by the instantaneous main circuit inductance of power tube IGBT 1, and absorption capacitor 2 is used to absorb the turn-off voltage generated by the instantaneous main circuit inductance of power tube IGBT 2; Absorption resistor 1 is used for damping the oscillating current formed between the capacitor and the main circuit inductance, and absorption resistor 2 is used for damping the oscillating current formed between the capacitor and the main circuit inductance.

6. A computer device, characterized in that: include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the control method of the reusable high-voltage fast electronic fuse described in any one of claims 4-5.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the control method of the reusable high-voltage fast electronic fuse as described in any one of claims 4-5.

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