High-voltage discharge circuit capable of rapidly discharging

Abstract

A high-voltage discharge circuit capable of discharging quickly comprises a drive circuit, a discharge resistor, a plurality of MOS (metal oxide semiconductor) tubes and optocouplers, inputs and outputs of the MOS tubes are sequentially connected in series and then are connected with the discharge resistor, a branch formed by connection is connected in parallel with a capacitor of an external high-voltage bus, each MOS tube corresponds to one optocoupler to form a standard unit, and topological structures of the standard units are the same; an energy storage capacitor, a first resistor and a second resistor are arranged in each standard unit, in each standard unit, a first end of a controlled end of the optocoupler is connected to a D pole of the MOS tube through the first resistor, the first end is connected to an S pole of the MOS tube after being connected in series with the energy storage capacitor, and a second end of the controlled end is connected to a G pole of the MOS tube through the second resistor; and the light emitting diodes of the optocouplers are jointly connected to the output end of the driving circuit to form unified control.

Description

TECHNICAL FIELD

[0001] The utility model is applied to the capacitor discharge circuit of positive high voltage or negative high voltage bus, especially relates to a high voltage discharge circuit of quick discharge. BACKGROUND

[0002] The power device MOS tube high voltage discharge circuit applied to the capacitor discharge circuit of positive high voltage or negative high voltage bus as shown in the figure, the single tube withstand voltage requirement is high in the high voltage output discharge occasion, and needs the driver to drive the power tube. Figure 1 UTILITY MODEL CONTENT

[0003] In order to improve the deficiency of prior art, the utility model provides a high voltage discharge circuit of quick discharge.

[0004] The high voltage discharge circuit includes drive circuit, discharge resistance and multiple MOS tubes and photoelectric coupler, the input and output of each MOS tube are connected in series in turn and connected with discharge resistance, the branch formed by connection is connected in parallel with the capacitor of high voltage bus outside, each MOS tube corresponds to a photoelectric coupler to form a standard unit, and the topological structure of each standard unit is same;Energy storage capacitor, first resistor and second resistor are arranged in each standard unit, in each standard unit, the first end of the controlled end of photoelectric coupler is connected to the D pole of MOS tube through first resistor, the first end is connected to the S pole of MOS tube after being connected with energy storage capacitor in series, and the second end of the controlled end is connected to the G pole of MOS tube through second resistor;The light emitting diode of each photoelectric coupler is commonly connected to the output end of drive circuit to form unified control.

[0005] Wherein, a stabilizing tube is arranged in each standard unit, in each standard unit, the first end of the controlled end of photoelectric coupler is connected to the cathode of stabilizing tube, and the anode of stabilizing tube is connected to the S pole of MOS tube.

[0006] Wherein, the discharge resistance has multiple, and each discharge resistance is connected in series at both ends of the branch formed by MOS tube connection.

[0007] Wherein, in each standard unit, the third resistor is connected between the D pole and the S pole of MOS tube, and the resistance value of each third resistor is same.

[0008] Wherein, the third resistor has two in each standard unit, and the two are connected in series and connected in parallel with filter capacitor.

[0009] Wherein, the drive circuit includes resistor R52, NPN tube, resistor R60, resistor R61, low-voltage power supply, the low-voltage power supply is connected to one end of the control end of each photoelectric coupler through resistor R52, the other end of each control end is connected after connection and the collector of NPN tube is connected, the emitter of NPN tube is grounded, the base is connected with external control signal through resistor R60, and the base of NPN tube is connected to the emitter through resistor R61. ​

[0010] Wherein, the base of the NPN transistor is further connected to the emitter through a filter capacitor C24.

[0011] Compared with the prior art, the utility model has the following advantages:

[0012] 1. The problem of insufficient voltage resistance of power tubes in high-voltage discharge is solved.

[0013] 2. The problem of needing a driving chip to drive the power tube is solved.

[0014] 3. The problem of needing external auxiliary power supply is solved.

[0015] 4. The power supply driving is realized by using the energy storage of the capacitor, and the discharge is quickly controlled. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 A conventional discharge circuit is shown.

[0017] Figure 2 A high-voltage discharge circuit of the utility model is shown. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the utility model will be described clearly and completely below with reference to the drawings in the embodiments of the utility model.

[0019] As shown in the drawings, Figure 2 The high-voltage discharge circuit includes a driving circuit, a discharge resistor, and a plurality of MOS tubes and optocouplers. The input and output of each MOS tube are connected in series and then connected to the discharge resistor. The branch formed by the connection is connected in parallel to the capacitor of the external high-voltage bus. Each MOS tube corresponds to an optocoupler to form a standard unit, and the topological structures of the standard units are the same. An energy storage capacitor, a first resistor, and a second resistor are arranged in each standard unit. In each standard unit, the first end of the controlled end of the optocoupler is connected to the D pole of the MOS tube through the first resistor, the first end is connected to the S pole of the MOS tube after being connected in series with the energy storage capacitor, and the second end of the controlled end is connected to the G pole of the MOS tube through the second resistor. The light-emitting diodes of the optocouplers are commonly connected to the output end of the driving circuit to form unified control.

[0020] In the circuit, R2, R6, R62, and R64 are discharge resistors. C4, C8, C12, C16, and C22 are energy storage capacitors that drive MOS. When the control signal is externally given, the driving circuit is turned on, the optocouplers in the drawing are almost simultaneously turned on, the energy storage capacitor provides a driving voltage to turn on the MOS tube, and the energy of the bus capacitor is consumed through R2, R6, R62, and R64. Therefore, a single control signal is used to drive multiple switching tubes, and the driving energy is controlled to supply power to the MOS tube by using simple capacitor storage.

[0021] Further, a voltage stabilizing tube is arranged in each standard unit, in each standard unit, the first end of the controlled end of the optocoupler is connected to the cathode of the voltage stabilizing tube, and the anode of the voltage stabilizing tube is connected to the S pole of the MOS tube. Figure 2 In the embodiment, TVS2, TVS4, TVS6, TVS8 and TVS10 are voltage stabilizing tubes. The voltage stabilizing tubes can stabilize the voltage in a reasonable range, which also corresponds to the voltage value of the energy storage capacitor.

[0022] Further, the discharge resistors are multiple, each of which is connected in series at both ends of the branch formed by the MOS tubes, as protection of both ends.

[0023] In each standard unit, the third resistor is connected between the D pole and the S pole of the MOS tube, each of the third resistors has the same resistance value, and voltage equalization is achieved. In each standard unit, the third resistor has two, which are connected in series and connected in parallel with a filter capacitor.

[0024] The driving circuit includes a resistor R52, an NPN tube, a resistor R60, a resistor R61, and a low-voltage power supply. The low-voltage power supply is connected to one end of the control end of each optocoupler through the resistor R52, the other end of each control end is connected after being connected, the collector of the NPN tube is connected, the emitter is grounded, the base is connected to an external control signal through the resistor R60, and the base of the NPN tube is connected to the emitter through the resistor R61. The NPN tube provides current amplification and drives each optocoupler to conduct at the same time. The base of the NPN tube is further connected to the emitter through the filter capacitor C24, so as to avoid mis-triggering caused by jitter.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited to the scope of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalent, without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A high voltage discharge circuit with fast bleed-down, characterized by: The drive circuit, the discharge resistor and the plurality of MOS tubes and the optical coupler are included, the input and output of each MOS tube are connected in series in turn and connected with the discharge resistor, the branch formed by the connection is connected in parallel with the capacitor of the high-voltage bus outside, each MOS tube corresponds to an optical coupler to form a standard unit, and the topological structures of the standard units are the same; the energy storage capacitor, the first resistor and the second resistor are arranged in each standard unit, in each standard unit, the first end of the controlled end of the optical coupler is connected to the D pole of the MOS tube through the first resistor, the first end is connected to the S pole of the MOS tube after being connected with the energy storage capacitor in series, the second end of the controlled end is connected to the G pole of the MOS tube through the second resistor, and the light-emitting diodes of the optical couplers are commonly connected to the output end of the drive circuit to form unified control.

2. The high-voltage discharge circuit according to claim 1, characterized in that: The voltage stabilizing tube is arranged in each standard unit, in each standard unit, the first end of the controlled end of the optical coupler is connected to the cathode of the voltage stabilizing tube, and the anode of the voltage stabilizing tube is connected to the S pole of the MOS tube.

3. The high-voltage discharge circuit according to claim 1, characterized in that: The discharge resistor has a plurality of discharge resistors, and each discharge resistor is connected in series at two ends of the branch formed by the MOS tubes in series.

4. The high-voltage discharge circuit according to claim 1, characterized in that: In each standard unit, the third resistor is connected across the D pole and the S pole of the MOS tube, and the resistances of the third resistors are the same.

5. The high-voltage discharge circuit according to claim 4, characterized in that: In each standard unit, the third resistor has two third resistors which are connected in series and have the filter capacitor connected in parallel.

6. The high-voltage discharge circuit according to claim 1, characterized in that: The drive circuit includes the resistor R52, the NPN tube, the resistor R60, the resistor R61 and the low-voltage power supply, the low-voltage power supply is connected to one end of the control end of each optical coupler through the resistor R52, the other end of each control end is connected after being connected, the collector of the NPN tube is connected, the emitter of the NPN tube is grounded, the base is connected to the external control signal through the resistor R60, and the base of the NPN tube is connected to the emitter through the resistor R61.

7. The high-voltage discharge circuit according to claim 6, characterized in that: The base of the NPN tube is further connected to the emitter through the filter capacitor C24.

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