Pulse high-voltage source with compact structure and small interference and laser

Abstract

The utility model discloses a pulse high-voltage source with a compact structure and small interference and a laser. The pulse high-voltage source comprises an interference elimination circuit, a DC / DC conversion circuit with adjustable output voltage, a self-oscillation circuit, an isolated resonant transformer high-voltage generation circuit, a voltage doubling rectifying circuit, a solid Marx parallel charging and series discharging nanosecond high-voltage pulse generation circuit and a synchronous magnetic isolation driving circuit. Input voltage generates adjustable output voltage VC after passing through the interference elimination circuit and the output voltage adjustable DC / DC conversion circuit, then generates standard sine high-voltage signals after passing through the self-oscillation circuit and the isolated resonant transformer high-voltage generation circuit, and then is subjected to high-voltage rectification by the voltage doubling rectification circuit to form direct-current high voltage HV. And finally, pulse high voltage is generated through a solid Marx parallel charging and series discharging nanosecond high-voltage pulse generation circuit and a synchronous magnetic isolation driving circuit. The pulse high-voltage source with compact structure and small interference and the laser have the characteristics of small volume, small interference, fast conversion speed, high reliability and the like.

Description

Technical Field

[0001] The utility model belongs to the field of electronic technology, and in particular relates to a pulse high-voltage source and a laser with compact structure and small interference. Background Art

[0002] In solid-state lasers, pulsed high voltage can compress continuous or pulsed laser energy, making the output laser peak power higher and the laser pulse width narrower. Pulsed high peak power lasers have simple structures and stable performance, and have been widely used in laser ranging and laser guidance. High-quality pulsed high voltage can meet the needs of narrow pulse high-power laser technology. A lot of research has been done on the working characteristics and features of pulsed high voltage at home and abroad to improve the output performance of lasers.

[0003] The pulse high voltage source generally requires a high voltage pulse of several thousand volts and nanoseconds, so the pulse high voltage signal cannot be transmitted over long distances. The pulse high voltage source should be as close to the laser as possible, so the pulse high voltage source is required to be small in size and compact in structure.

[0004] Pulse high-voltage sources have rapid changes in high voltage, so they will produce large electromagnetic interference. High-power narrow-pulse lasers are mostly used in laser ranging and laser guidance. These applications all require weak electrical signal detection. How to reduce the impact of interference on weak electrical signal detection has become one of the key technologies of the system. Utility Model Content

[0005] In order to solve the technical problems existing in the prior art, the utility model provides a pulse high-voltage source and a laser with compact structure and small interference, which have the characteristics of small size, small interference, fast conversion speed, high reliability and the like.

[0006] The technical solutions adopted by the utility model to solve the above technical problems are as follows:

[0007] A pulse high-voltage source with compact structure and low interference, comprising an interference elimination circuit, a DC / DC conversion circuit with adjustable output voltage, a self-excited oscillation circuit, an isolated resonant transformer high-voltage generation circuit, a voltage doubling rectification circuit, a solid Marx parallel charging and series discharging circuit to generate nanosecond-level high-voltage pulses, and a synchronous magnetic isolation drive circuit;

[0008] The input voltage generates an adjustable output voltage VC after passing through the interference elimination circuit and the DC / DC conversion circuit with adjustable output voltage, and then generates a standard sinusoidal high voltage signal through the self-excited oscillation circuit and the isolated resonant transformer high voltage generation circuit, and then is rectified into a DC high voltage HV by the voltage doubler rectifier circuit, and finally generates a nanosecond high voltage pulse circuit and a synchronous magnetic isolation drive circuit to generate a pulse high voltage.

[0009] Furthermore, the interference elimination circuit includes a differential mode capacitor C1, a Y capacitor and a common mode inductor L1; two ends of the input voltage sequentially pass through the differential mode capacitor C1 and the Y capacitor and then enter two input ends of the common mode inductor L1.

[0010] Further, the DC / DC conversion circuit with adjustable output voltage includes a DC / DC converter U1, a second resistor R2, a fourth resistor R4 and a fifth resistor R5;

[0011] The negative pole of the two output ends of the common-mode inductor L1 is grounded, and the positive pole is connected to the input end of the DC / DC converter U1. The output end of the DC / DC converter U1 is grounded through the second resistor R2 and the fourth resistor R4; the input level signal V1 is connected to the feedback end FB of the DC / DC converter U1 through the fifth resistor R5. The feedback end FB of the DC / DC converter U1 is also connected to the connection point of the second resistor R2 and the fourth resistor R4. The output end of the DC / DC converter U1 generates an adjustable output voltage VC.

[0012] Furthermore, the interference elimination circuit also includes a common mode inductor L3, and an input voltage generates an input level signal V1 after passing through the common mode inductor L3.

[0013] Furthermore, the DC / DC conversion circuit with adjustable output voltage further includes a first resistor R1, a third capacitor C3, a fifth capacitor C5 and an eighth capacitor C8;

[0014] The enable end of the DC / DC converter U1 is connected to the positive electrode of the two output ends of the common-mode inductor L1 through the first resistor R1, the soft start end of the DC / DC converter U1 is grounded through the fifth capacitor C5, and the third capacitor C3 and the eighth capacitor C8 are connected to both ends of the second resistor R2 and the fourth resistor R4 respectively.

[0015] Further, the self-excited oscillation circuit includes a first transistor V1, a second transistor V2, a sixth capacitor C6, a sixth resistor R6 and a light-emitting diode H1; the isolated resonant transformer high-voltage generating circuit includes a transformer T1;

[0016] The bases of the two transistors are connected to the first winding of the primary stage of the transformer T1, the collectors of the two transistors are connected to the second winding of the primary stage of the transformer T1, and the emitters of the two transistors are grounded; the sixth capacitor C6 is connected to the collectors of the two transistors, the adjustable output voltage VC is connected to the tap of the second winding and is also grounded through the sixth resistor R6 and the light-emitting diode H1; the secondary stage of the transformer T1 generates a standard sinusoidal high voltage signal.

[0017] Further, the voltage doubler rectifier circuit includes a first diode D1, a second diode D2, a third diode D3, a seventh capacitor C7 and a seventh resistor R7;

[0018] The anode of the third diode D3 is connected to one end of the secondary stage of the transformer T1, the cathode of the third diode D3 is connected to the cathode of the first diode D1 and the anode of the second diode D2, the anode of the first diode D1 is connected to the other end of the secondary stage of the transformer T1, and the cathode of the second diode D2 is connected to the other end of the secondary stage of the transformer T1 through the seventh capacitor C7 and the seventh resistor R7 connected in parallel.

[0019] Furthermore, the solid Marx parallel charging and serial discharging circuit for generating nanosecond-level high-voltage pulses includes n-level solid Marx circuits; each level of the solid Marx circuit includes two diodes, a MOSFET tube and a high-voltage capacitor;

[0020] The last stage of solid Marx circuit generates nanosecond falling edge high voltage pulse.

[0021] Furthermore, the synchronous magnetic isolation driving circuit includes a magnetic ring, one input generates n control outputs, and controls n-level solid-state Marx circuits.

[0022] A laser uses any one of the above-mentioned pulse high voltage sources with compact structure and small interference to generate pulse high voltage.

[0023] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0024] 1. The self-resonant circuit and Marx circuit are used to generate high-voltage pulses up to several thousand volts, while ensuring the small size of the circuit structure and low power consumption, so as to achieve a compact structure of the pulse high-voltage source.

[0025] 2. The use of transformer-isolated resonant conversion, synchronous isolated magnetic drive and integrated differential-mode and common-mode interference elimination circuits can effectively suppress the interference generated during the circuit operation process, solving the problem of pulsed high-voltage source interference affecting the signal-to-noise ratio of weak current signal processing such as laser ranging.

[0026] 3. By adjusting the amplitude of the level signal, the pulse high voltage signal of several thousand volts can be continuously adjusted to meet the requirements of adaptability to different temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The overall block diagram of the pulse high voltage source with compact structure and low interference;

[0028] Figure 2 The circuit diagram of the interference elimination circuit and the DC / DC conversion circuit with adjustable output voltage;

[0029] Figure 3 The circuit diagram is a self-excited oscillation circuit, an isolated resonant transformer high voltage generation circuit and a voltage doubler rectifier circuit;

[0030] Figure 4 is a circuit diagram of a synchronous magnetic isolation drive circuit;

[0031] Figure 5 The circuit diagram of the solid Marx parallel charging and series discharging circuit to generate nanosecond high voltage pulses;

[0032] Figure 6 This is the nanosecond high-voltage pulse waveform measured by the high-voltage probe. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation methods described herein are used to explain the utility model and are not used to limit the utility model. In addition, the technical features involved in each implementation method of the utility model described below can be combined with each other as long as they do not conflict with each other.

[0034] The utility model provides a pulse high-voltage source and a laser with compact structure and small interference, which have the characteristics of small volume, small interference, fast conversion speed, high reliability and the like.

[0035] The utility model has a compact structure and low interference pulse high voltage source, comprising:

[0036] The self-excited oscillation circuit (N3) generates a pulse width modulation signal (PWM). The transistors V1 and V2 are used to form a mirror circuit to generate self-excited oscillation. By setting different parameters, a PWM signal that meets the design requirements is generated.

[0037] An isolated resonant transformer high voltage generating circuit (N4) generates a standard sinusoidal voltage signal at the primary stage through transformer primary and capacitor parameters, and an isolated transformer secondary stage generates a standard sinusoidal high voltage signal, converting a DC power supply into an AC high voltage power supply through voltage resonance;

[0038] The voltage doubler rectifier circuit (N5) rectifies the standard sinusoidal high voltage signal generated by the transformer secondary stage into a DC high voltage through capacitors and diodes;

[0039] Solid Marx parallel charging and serial discharging nanosecond high-voltage pulse generating circuit (N6), n-level solid Marx circuit, the solid Marx circuit is composed of MOSFET Q1-Qn and diodes D4-Dn. When the driving signal is low, the high-voltage source charges the parallel capacitor through the diode. When the driving signal is high, the capacitor voltages are superimposed in series and output nanosecond falling edge high-voltage pulses;

[0040] Synchronous magnetic isolation drive circuit (N7), using magnetic ring, 1-level input controls n-level isolated synchronous floating output, respectively controls Q1-Qn to turn on or off;

[0041] The DC / DC conversion circuit (N2) with adjustable output voltage has a wide range of DC power input, and the output high voltage amplitude can be adjusted in a wide range through a potentiometer or a level signal (DA signal). When the pulse high voltage is generated, strong electromagnetic interference will be generated. If no interference elimination measures are taken, it will affect the normal operation of the system. Common mode inductors and Y capacitors are used to eliminate common mode interference (N1), and capacitors and magnetic beads are used to eliminate differential mode interference.

[0042] In some embodiments, the self-excited oscillation circuit (N3) generates a PWM signal only through the self-excited oscillation circuit composed of transistors V1 and V2, and does not require the dedicated chip (PWM chip, single-chip microcomputer, ARM, FPGA, etc.), dedicated chip power supply circuit, dedicated chip peripheral circuit and software required for traditional PWM signal generation, making the circuit simple and compact.

[0043] In some embodiments, the primary stage of the resonant transformer generates a standard sinusoidal voltage, and the secondary stage of the resonant transformer generates a standard high-voltage sinusoidal voltage. Voltage resonant conversion is used to reduce switching interference during the conversion process. The primary and secondary stages are isolated and block the transmission path of the interference source, thereby effectively suppressing interference.

[0044] In some embodiments, a solid Marx parallel charging and serial discharging nanosecond high-voltage pulse generating circuit is mainly composed of a small-package high-voltage MOSFET, a high-voltage capacitor and a diode. The Marx parallel charging and serial discharging circuit consumes energy only during parallel charging when the power is turned on. During the switching process, the voltage on the capacitor remains unchanged and no energy is released. Therefore, this part of the circuit has low power consumption. Since the required power supply power is small, a small-package DC / DC conversion circuit, a resonant transformer and a power MOSFET can be selected, so the driver is small in size and compact in structure.

[0045] In some embodiments, a synchronous magnetic isolation drive circuit, with one input generating n synchronous floating outputs, has a small size and compact structure, and input and output isolation effectively reduces interference.

[0046] In some embodiments, the DC / DC power conversion has a wide input voltage range, a wide range of applications, and an adjustable output voltage over a wide range, suitable for different types of loads. It can be adjusted using a potentiometer or a level signal, and is easy to debug.

[0047] In some embodiments, the power supply circuit loop and the control signal circuit loop adopt common mode and differential mode comprehensive interference elimination measures to reduce the impact of interference on the system.

[0048] like Figure 1As shown, the pulse high voltage source of this embodiment has a compact structure and low interference, including an interference elimination circuit (N1); a DC / DC conversion circuit with adjustable output voltage (N2); a self-excited oscillation circuit (N3) for generating a pulse width modulation signal (PWM); an isolated resonant transformer high voltage generating circuit (N4); a voltage doubling rectifier circuit (N5); a solid Marx parallel charging and series discharging circuit for generating nanosecond-level high voltage pulses (N6); a synchronous magnetic isolation drive circuit (N7), etc.

[0049] The principle is: a common-mode inductor and a Y capacitor eliminate a common-mode interference circuit (N1); a DC / DC conversion circuit (N2) with adjustable output voltage, which adjusts the power supply output size through the amplitude of the level signal, and realizes continuous adjustment of the pulse high-voltage signal of several thousand volts to meet the requirements of different temperature environments; a self-excited oscillation circuit (N3) generates a pulse width modulation signal, which only requires two transistors, a capacitor, and a resistor to self-resonate and generate a PWM signal; an isolated resonant transformer high-voltage generation circuit (N4), the primary and secondary of the transformer are isolated, and the resonant conversion rather than the hard switch conversion effectively reduces the switching interference of the high-voltage generation circuit; a voltage doubler rectifier circuit (N5), which doubles and rectifies the sinusoidal voltage generated by N4; a solid Marx parallel charging and series discharging nanosecond high-voltage pulse generation circuit (N6), the parallel charging loop has a large resistance and a small capacitance, so the current during the charging process is very small (only a few microamperes); during the series discharge process, only the parasitic capacitance of Q1-Qn is discharged, and the capacitor voltage remains unchanged, so the discharge process consumes almost no energy, which can reduce the volume of the power supply and reduce the electromagnetic interference to the power supply. The synchronous magnetic isolation driving circuit (N7) realizes n-channel output synchronous isolation driving signals by adopting a small magnetic ring.

[0050] Figures 2 to 6 This is an embodiment of a compact interference small pulse high voltage source. Figure 2 As shown, a power chip is used as a DC / DC conversion circuit (N1) with adjustable output. Under the combined action of R2, R4 and input V1 (level signal), the output voltage VC of N1 can be adjusted. Figure 3 As shown, VC generates a standard sinusoidal voltage signal at the primary stage of the transformer through the self-excited oscillation circuit, and the isolated secondary stage of the transformer generates a standard sinusoidal high voltage. The standard sinusoidal high voltage generated by the secondary stage of the transformer is rectified into a DC high voltage HV through diodes D1, D2 and capacitor C7. Figure 4 As shown, the synchronous magnetic isolation drive circuit uses a magnetic ring (L5), and the 1st level input controls the 10th level of isolated synchronous floating output, which controls Q1-Q10 to turn on or off respectively. Figure 5As shown in the figure, the 10-level solid Marx circuit composed of MOSFET Q1-Q10, capacitor C9-C18, and diode D4-D23, when the drive signal is low, Q1-Q10 is turned off, and the high voltage source charges the parallel C9-C18 through the diode. When the drive signal is high, Q1-Q10 is turned on, and the voltage of C9-C18 is superimposed in series, and a nanosecond falling edge high voltage pulse is output. Figure 6 As shown in the figure, this is the nanosecond high voltage pulse waveform measured by a 1000:1 high voltage probe.

[0051] The utility model also provides a laser, which uses any one of the above-mentioned pulse high-voltage sources with compact structure and small interference to generate pulse high voltage.

[0052] In summary, the utility model designs a pulse high-voltage source with compact structure and small interference, which includes an interference elimination circuit (N1), a DC / DC conversion circuit with adjustable output voltage (N2), a self-excited oscillation circuit (N3), an isolated resonant transformer high-voltage generation circuit (N4), a voltage doubling rectification circuit (N5), a solid Marx parallel charging and series discharging nanosecond high-voltage pulse generation circuit (N6), and a synchronous magnetic isolation drive circuit (N7). The utility model is used to eliminate the common mode interference circuit (N1) of the common mode inductor and the Y capacitor, and the DC / DC conversion circuit (N2) with adjustable output voltage, which adjusts the power supply output size by the amplitude of the level signal, realizes the continuous adjustment of the high voltage pulse signal of several thousand volts, and meets the requirements of different temperature environments; the self-excited oscillation circuit (N3) generates a pulse width modulation signal, and only needs two triodes, capacitors, and resistors to self-resonate and generate a PWM signal; the isolated resonant transformer high voltage generating circuit (N4), the transformer primary and secondary isolation, resonant conversion rather than hard switch conversion, effectively reduces the switching interference of the high voltage generating circuit; the voltage doubling rectification circuit (N5), using diodes and capacitors to rectify the sinusoidal high voltage generated by N4; the solid Marx parallel charging and series discharging nanosecond high voltage pulse generating circuit (N6), the parallel charging loop resistance is very large, the capacitance is very small, so the current in the charging process is very small (only a few microamperes); in the series discharge process, only the parasitic capacitance of Q1-Qn is discharged, and the voltage of C1-Cn remains unchanged, so the discharge process consumes almost no energy, which can reduce the power supply volume and reduce the electromagnetic interference to the power supply. The synchronous magnetic isolation driving circuit (N7) realizes n-channel output synchronous isolation driving signals by adopting a small magnetic ring.

[0053] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pulsed high voltage source with compact structure and low interference, characterized in that: It includes interference elimination circuit, DC / DC conversion circuit with adjustable output voltage, self-excited oscillation circuit, isolated resonant transformer high voltage generation circuit, voltage doubling rectification circuit, solid Marx parallel charging and series discharging circuit to generate nanosecond high voltage pulse circuit and synchronous magnetic isolation drive circuit; The input voltage generates an adjustable output voltage VC after passing through the interference elimination circuit and the DC / DC conversion circuit with adjustable output voltage, and then generates a standard sinusoidal high voltage signal through the self-excited oscillation circuit and the isolated resonant transformer high voltage generation circuit, and then is rectified into a DC high voltage HV by the voltage doubler rectifier circuit, and finally generates a nanosecond high voltage pulse circuit and a synchronous magnetic isolation drive circuit to generate a pulse high voltage.

2. The pulse high voltage source with compact structure and low interference according to claim 1 is characterized in that: The interference elimination circuit includes a differential mode capacitor C1, a Y capacitor and a common mode inductor L1; two ends of the input voltage enter the two input ends of the common mode inductor L1 after passing through the differential mode capacitor C1 and the Y capacitor in sequence.

3. The pulse high voltage source with compact structure and low interference according to claim 2 is characterized in that: The DC / DC conversion circuit with adjustable output voltage includes a DC / DC converter U1, a second resistor R2, a fourth resistor R4 and a fifth resistor R5; The negative pole of the two output ends of the common-mode inductor L1 is grounded, and the positive pole is connected to the input end of the DC / DC converter U1. The output end of the DC / DC converter U1 is grounded through the second resistor R2 and the fourth resistor R4; the input level signal V1 is connected to the feedback end FB of the DC / DC converter U1 through the fifth resistor R5. The feedback end FB of the DC / DC converter U1 is also connected to the connection point of the second resistor R2 and the fourth resistor R4. The output end of the DC / DC converter U1 generates an adjustable output voltage VC.

4. The pulse high voltage source with compact structure and low interference according to claim 3 is characterized in that: The interference elimination circuit further includes a common mode inductor L3. An input voltage generates an input level signal V1 after passing through the common mode inductor L3.

5. The pulse high voltage source with compact structure and low interference according to claim 3 is characterized in that: The DC / DC conversion circuit with adjustable output voltage further includes a first resistor R1, a third capacitor C3, a fifth capacitor C5 and an eighth capacitor C8; The enable end of the DC / DC converter U1 is connected to the positive electrode of the two output ends of the common-mode inductor L1 through the first resistor R1, the soft start end of the DC / DC converter U1 is grounded through the fifth capacitor C5, and the third capacitor C3 and the eighth capacitor C8 are connected to both ends of the second resistor R2 and the fourth resistor R4 respectively.

6. The pulse high voltage source with compact structure and low interference according to claim 1 is characterized in that: The self-excited oscillation circuit includes a first transistor V1, a second transistor V2, a sixth capacitor C6, a sixth resistor R6 and a light-emitting diode H1; the isolated resonant transformer high-voltage generating circuit includes a transformer T1; The bases of the two transistors are connected to the first winding of the primary stage of the transformer T1, the collectors of the two transistors are connected to the second winding of the primary stage of the transformer T1, and the emitters of the two transistors are grounded; the sixth capacitor C6 is connected to the collectors of the two transistors, the adjustable output voltage VC is connected to the tap of the second winding and is also grounded through the sixth resistor R6 and the light-emitting diode H1; the secondary stage of the transformer T1 generates a standard sinusoidal high voltage signal.

7. The pulse high voltage source with compact structure and low interference according to claim 6 is characterized in that: The voltage doubler rectifier circuit includes a first diode D1, a second diode D2, a third diode D3, a seventh capacitor C7 and a seventh resistor R7; The anode of the third diode D3 is connected to one end of the secondary stage of the transformer T1, the cathode of the third diode D3 is connected to the cathode of the first diode D1 and the anode of the second diode D2, the anode of the first diode D1 is connected to the other end of the secondary stage of the transformer T1, and the cathode of the second diode D2 is connected to the other end of the secondary stage of the transformer T1 through the seventh capacitor C7 and the seventh resistor R7 connected in parallel.

8. The pulse high voltage source with compact structure and low interference according to claim 1 is characterized in that: The solid Marx parallel charging and serial discharging circuit for generating nanosecond high-voltage pulses includes n-level solid Marx circuits; each level of the solid Marx circuit includes two diodes, a MOSFET tube and a high-voltage capacitor; The last stage of solid Marx circuit generates nanosecond falling edge high voltage pulse.

9. The pulse high voltage source with compact structure and low interference according to claim 8 is characterized in that: The synchronous magnetic isolation driving circuit includes a magnetic ring, one input generates n control outputs, and controls n-level solid Marx circuits.

10. A laser, characterized in that: The laser generates pulsed high voltage by using the pulsed high voltage source with compact structure and small interference as described in any one of claims 1 to 9.

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