High-voltage transient waveform generating device and construction method

Abstract

The application discloses a high-voltage transient waveform generating device and a construction method. The device comprises a signal source, a switching device, a power supply A, a power supply B, a coupling transformer and a load. The voltage of the power supply B is output to the load to provide a rated voltage required by an airborne equipment for normal operation. The signal source provides a trigger signal for the switching device under the control of a graphical program to control the conduction and turn-off of the switching device. The power supply A superimposes a transient voltage on both ends of the load through the self-made coupling transformer under the control of the switching device to generate a high-voltage transient waveform. The voltage of the power supply B is 270-540 V DC voltage. The application can be used in the high-voltage power supply compatibility test of the airborne equipment and can construct overvoltage transient and undervoltage transient voltage waveforms.

Description

Technical Field

[0001] This invention relates to the field of electronic equipment technology, and in particular to a high-voltage transient waveform generator and its construction method. Background Technology

[0002] The power supply characteristics and requirements for aircraft electrical equipment are specified in GJB 181B-2012. This standard applies to the coordination between aircraft power supply systems, external power sources, and electrical equipment. Based on the characteristics of aircraft power supply systems, the mainstream power supply systems currently provide the following voltage types: DC 28V, DC 270V, single-phase AC (115V, 400Hz), three-phase AC (115V / 200V, 400Hz), single-phase variable frequency AC (115V), three-phase variable frequency AC (115V / 200V), and single-phase AC (220V, 50Hz)—a total of seven types.

[0003] Under different voltages, the corresponding operating states can be divided into six categories: normal, transition, abnormal, emergency, engine electric start, and power supply failure. Under normal operating conditions, power supply compatibility testing mainly includes five assessment items: load characteristics, normal steady-state voltage, voltage distortion spectrum, pulsation, and normal voltage transients. For different assessment items, the programmable power supply needs to output different test waveforms and test levels. Normal voltage transients are divided into overvoltage transients, undervoltage transients, mixed transients, and repetitive transients: an overvoltage transient can be represented as a short voltage pulse of a specific magnitude superimposed on the steady-state voltage; an undervoltage transient can be represented as a short voltage pulse of a certain magnitude decreasing the steady-state voltage; and a mixed transient can be represented as both overvoltage and undervoltage short pulses superimposed on the steady-state voltage.

[0004] The patent application with application number CN201710084936.0 can be used to measure the input voltage performance of equipment powered by DC power systems in telecommunications environments. It is applicable to the testing and analysis of the ANSI T1.315 standard, improving the reliability and operation and maintenance efficiency of optical communication networks while reducing R&D and operation costs. The purpose of this invention is to provide a low-cost undervoltage and overvoltage transient measurement device for the R&D and maintenance of telecommunications transmission equipment. To ensure the practical feasibility of transient testing, an undervoltage and overvoltage transient measurement circuit was designed, providing a convenient, fast, and low-cost solution for measuring the power transient performance of communication equipment. This voltage transient testing scheme can flexibly change various test conditions and is applicable to some standard-compatible tests and analyses. It mainly achieves the output of overvoltage and undervoltage pulses by controlling the switching of MOSFET devices via pulses. However, the maximum voltage amplitude of this output is only 75.2V. For some systems requiring high-voltage power supply (rated voltage greater than 270V), this testing device cannot provide the required voltage and amplitude. Summary of the Invention

[0005] To address the shortcomings of the prior art, this invention provides a high-voltage transient waveform generation device and construction method. By employing pulse control with an adjustable duty cycle, the steady-state voltage and transient voltage are superimposed, thereby constructing a normal high-voltage transient voltage waveform. This invention can superimpose a voltage signal with a specific voltage pulse onto a specific supply voltage.

[0006] The primary objective of this invention is to provide a device for generating high-voltage transient waveforms.

[0007] The second objective of this invention is to provide a method for constructing high-voltage transient waveforms.

[0008] The first objective of this invention can be achieved by adopting the following technical solution:

[0009] A high-voltage transient waveform generator includes a signal source, switching devices, power supply A, power supply B, a coupling transformer, and a load. Power supply B outputs voltage to the load to provide a rated voltage. Under the control of a graphical program, the signal source provides a trigger signal to the switching devices to control their on / off states. Under the control of the switching devices, power supply A superimposes the transient voltage across the load via the coupling transformer to generate a high-voltage transient waveform. The voltage of power supply B is a DC voltage of 270–540V.

[0010] Preferably, the signal source, under the control of a graphical program, provides a trigger signal to the switching device to control the switching device's on and off states, including:

[0011] The computer accesses the VISA serial port via a network cable through a graphical program. The output signal of the VISA serial port control signal source is a PWM square wave signal, and the output is enabled in the output program of the signal source. The PWM square wave signal controls the switching devices to turn on and off.

[0012] Preferably, before controlling the signal source using a graphical program, the IP addresses of the signal source and the computer are set so that the signal source and the computer are on the same local area network.

[0013] Preferably, the graphical program is implemented using the LabVIEW language, and the library functions corresponding to the signal source are deployed in the LabVIEW library file.

[0014] Preferably, the switching device is a MOS device.

[0015] Preferably, the MOS device is a B2M030120H silicon carbide MOS transistor; the signal output of the signal source is connected between the gate and source of the B2M030120H silicon carbide MOS transistor, and the load is connected between the drain and source of the B2M030120H silicon carbide MOS transistor.

[0016] Preferably, the switching time between the voltages of power supply A and power supply B is less than the order of milliseconds.

[0017] Preferably, the voltage of the power supply A is determined according to the transient voltage value of the relevant industry standard, and the voltage output by the signal source is 0 to 3V.

[0018] Preferably, if the turns ratio of the coupling transformer is 1:1, the primary side of the coupling transformer is wound with two cables in parallel on a magnetic ring, and the secondary side is wound with a single coil output.

[0019] The second objective of this invention can be achieved by adopting the following technical solution:

[0020] A method for constructing a high-voltage transient waveform, based on the aforementioned high-voltage transient waveform generator, includes:

[0021] The voltage of power supply B is output to the load to provide the rated voltage; the voltage of power supply B is 270-540V DC.

[0022] The signal source is controlled by a graphical program to output a square wave pulsating signal; the high-level amplitude of the square wave signal is 10V, the low-level amplitude is 0V, the duty cycle of the square wave is 50%, the period of the square wave signal is 0.1ms, and the corresponding frequency is 10kHz.

[0023] The signal source outputs a signal to control the switching device's on / off state; the MOSFET's on-threshold V... GS(th) The voltage is 2.3 to 3.5V; therefore, the signal source outputs a square wave signal with a high voltage of 3V, a low voltage of 0V, and a frequency of 10kHz; the high level of 3V has reached the turn-on voltage of the MOSFET, so the switching device is synchronously turned on and off according to the high voltage level of the signal source.

[0024] When the switching device is turned on, the transient voltage of power supply A is superimposed on the load terminals through the coupling transformer to generate a high-voltage transient waveform; the amplitude of the transient waveform is:

[0025]

[0026] Where T is the square wave signal period of 0.1ms, and t is the time axis.

[0027] The present invention has the following advantages over the prior art:

[0028] The high-voltage transient waveform generation device and construction method provided by the present invention can be used in the high-voltage power supply compatibility test of airborne equipment, and can construct voltage waveforms of overvoltage transients and undervoltage transients. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the high-voltage transient waveform generator according to an embodiment of the present invention;

[0031] Figure 2 This is a flowchart of a graphical program according to an embodiment of the present invention;

[0032] Figure 3 A schematic diagram illustrating the setting of the signal source IP address in an embodiment of the present invention;

[0033] Figure 4 A schematic diagram illustrating the setting of computer IP addresses in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the hardware portion of an embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the pin distribution of the B2M030120H silicon carbide MOS transistor according to an embodiment of the present invention;

[0036] Figure 7 This is a circuit diagram of the switching device when it is disconnected according to an embodiment of the present invention;

[0037] Figure 8 This is a schematic diagram of the voltage waveform signal output by the switching device when it is disconnected according to an embodiment of the present invention;

[0038] Figure 9 This is a circuit diagram of the switching device when it is closed according to an embodiment of the present invention;

[0039] Figure 10 This is a schematic diagram of the voltage waveform signal output when the switching device is closed according to an embodiment of the present invention;

[0040] Figure 11 This is a schematic diagram of the transformer winding according to an embodiment of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be understood that the specific embodiments described are merely used to explain this application and are not intended to limit this application.

[0042] Example:

[0043] like Figure 1 As shown, this embodiment provides a high-voltage transient waveform generator, including a graphical program and a hardware component. The hardware component includes a signal source, switching devices, power supply A, power supply B, a coupling transformer, and a load, wherein:

[0044] (1) Graphical program part.

[0045] A signal source is used to provide trigger signals to switching devices to control their on / off states. The output delay and waveform of the trigger signal are controlled by a graphical program. Controlling the high-voltage signal provided by power supply A using a low-voltage signal from the signal source can effectively improve the operational safety of the equipment and ensure the safety of the operators.

[0046] When the graphics program controls the output to a high level, it can effectively turn on the MOS device. At this time, the signal in power supply A is directly output to the load through the coupling transformer.

[0047] refer to Figure 2 The graphical program accesses the VISA serial port resources through the computer's network port, and then controls the output signal of the signal source to be a square wave signal, and configures the output (T) of the signal source Output program to be enabled; then the signal source outputs the corresponding square wave signal from the port of the signal generator to control the conduction and shutdown of the switching MOS device.

[0048] The graphical program is implemented using LabVIEW, a language that can interoperate and control C and Python. To achieve the corresponding functions, the IP address of the signal source first needs to be set. In this embodiment, the IP address of the signal source is set to 192.168.0.253, and the subnet mask is set to 255.255.0.0. To enable normal communication between the signal source and the host computer, the IP address of the computer running the host computer software needs to be set to 192.168.0.252, and the subnet mask needs to be set to 255.255.0.0. This ensures that the signal source and the computer are on the same network segment and can maintain normal communication. (Refer to...) Figure 3, 4 .

[0049] After completing the setup, you can use the Windows command window to ping the signal source's IP address to check for a response. After setting the IP address, you need to start writing the signal source control program. Since the host computer and the signal source are connected via a network port, in most cases the network port cannot directly control the instrument from the PC; therefore, a driver program is required. This driver program needs to use the corresponding signal source driver. For example, if using an Agilent 33500B Series signal source, the corresponding library function needs to be deployed in the LabVIEW library file; and the library function needs to be placed in the instr.lib file in the National Instruments folder under the installation folder to complete the driver deployment.

[0050] After installing and configuring the library functions, you need to edit them in the LabVIEW program interface. Figure 2 In the Waveform Generator VISA Resource, the TCP / IP interface address between the signal generator and the computer is used to enable communication between the host computer and the signal generator. Then, the signal control function of the signal generator is called to control the output waveform to be a square wave with a frequency of 10000Hz; and the signal output module is enabled (T) for signal output. This completes the control and output of the signal generator.

[0051] (2) Hardware part.

[0052] The schematic diagram for the hardware part can be referenced. Figure 5 . Figure 5 In the diagram, V3 represents the waveform output by the graphical control program's control signal source, V2 represents power supply A, V1 represents power supply B, and S2 represents the switching MOS device. Subsequently, the transient signal is output to the load R1 through the 1:1 coupling transformer T2, thereby achieving the purpose of superimposing the signal on the high-voltage waveform.

[0053] (2-1) Signal source.

[0054] Used to output a PWM square wave signal to control the on and off of the switching device. The pulse width and frequency of the PWM square wave signal can be defined according to actual needs. A high level turns on the switching device, allowing the voltage of power supply A to be output to the load through the coupling transformer.

[0055] (2-2) Switching devices.

[0056] Since the switching device needs to withstand voltage from power supply A during and after the switching process, the withstand voltage of the switching device should be at least able to withstand the voltage U of power supply A simultaneously.A That is, the breakdown voltage U of the device breakdown It should be at least ≥ U A In this embodiment, 540V is used as the basic DC voltage. Therefore, with a margin of 2, the breakdown voltage of the switching device is at least 1080V. Furthermore, the switching between the two power supplies should be on the order of milliseconds; therefore, the switching time of the switching device should be at least on the order of microseconds. Information on this device can be found in the relevant information in the single-tube datasheet.

[0057] In practical applications, to meet the demand for domestically produced products, the B2M030120H silicon carbide MOSFET was selected as the switching device. The relevant parameters of this device are shown in Table 1.

[0058] Table 1 Performance Specifications of B2M030120H Silicon Carbide MOSFET

[0059]

[0060] The transistor can withstand a voltage of 1200V, thus meeting the breakdown voltage requirement. Table 2 shows the transistor's turn-on delay time (t). d(on) =44ns) and rise time (t r The sum of (32ns) is 76ns, which is much smaller than the microsecond-level conversion time requirement; similarly, the single-tube turn-off delay time (t) d(off) =39ns) and fall time (t f The sum of (12ns) is 51ns, which is also much smaller than the conversion time requirement of microseconds.

[0061] Table 2. Switching characteristics of B2M030120H silicon carbide MOSFET

[0062]

[0063] In actual connection, connect the signal output of the signal source between the gate (Gate(1)) and source (Source(3)) of the MOSFET, and connect the load between the drain (Drain(2)) and source (Source(3)). The pinout of the MOSFET can be found in [reference needed]. Figure 6 .

[0064] (2-3) Power supply A and power supply B.

[0065] Power supply B is used to provide a high-voltage DC signal, serving as the main high-voltage source. Power supply A works in conjunction with power supply B, achieving waveform superposition through switching control.

[0066] By controlling the on / off state of the switching device, the output of power supply A is superimposed on the load at a specific moment to form a high-voltage transient waveform.

[0067] In this embodiment, power supply B is used to provide 540V DC voltage, and power supply A outputs 0-10V.

[0068] Under the control of a graphical program, the signal source signals superimpose the outputs of power supply A and power supply B onto the load equipment through switching devices, thereby achieving an output with a specific high-voltage transient waveform.

[0069] When the switching device is open, the corresponding circuit is as follows: Figure 7 As shown, a voltage of 0V for signal source V3 indicates that the switching device is in the off state. Figure 8 The corresponding waveform is the DC voltage waveform signal of the load outputting 540V alone (that is, when the switching device is in the open state, the output is not superimposed), and this signal continuously outputs a stable 540V.

[0070] Figure 9 This indicates that the switching device in the circuit is in the ON state. Figure 10 The corresponding waveform is the voltage waveform signal output by the load, that is, the output of power supply A and the output of power supply B are superimposed on the load.

[0071] Because transient signals have a rich spectral content, and high-voltage transients are characterized by short duration and high energy, using a general-purpose 1:1 signal transformer in series with the signal at the moment the signal source is switched on will inevitably cause deviations in the response of the downstream load or damage to the transformer due to its inability to handle the high power. Therefore, the transformer used in high-voltage transient generators needs to be designed according to the following specifications: Figure 11 The schematic diagram shows the winding process. Two cables are wound in parallel around a magnetic ring. By winding the two coils, the input impedance of the transformer can be reduced under the same signal input, thereby increasing the power intensity that the corresponding transformer winding can withstand, and ultimately achieving a good output of transient signals.

[0072] This embodiment also provides a method for constructing a high-voltage transient waveform, implemented based on the aforementioned high-voltage transient waveform generator, including:

[0073] The voltage (DC 540V) of power supply B is output to the load to provide the rated voltage, as shown in the output value. Figure 8 As shown, the voltage output amplitude is displayed as 540.000V in Channel A.

[0074] The signal source is controlled by a graphical program to output a 10V square wave pulsating signal (the high level amplitude of the square wave signal is 10V, the low voltage amplitude is 0V, the duty cycle of the square wave is 50%, the period of the square wave signal is 0.1ms, and the corresponding period is 10kHz).

[0075] The signal source outputs a signal to control the switching device's on and off states. According to Table 3, the MOSFET's on-threshold (V...)... GS(th) =2.3~3.5V), so the signal source outputs a square wave signal with a high voltage of 3V, a low voltage of 0V, and a frequency of 10kHz; the high level of 3V has reached the conduction voltage of the MOSFET, so the switching device is synchronously turned on and off according to the high voltage level of the signal source.

[0076] Table 3 Electrical characteristics of B2M030120H silicon carbide MOSFET

[0077]

[0078] When the switching device is turned on, the transient voltage of power supply A is superimposed across the load through a coupling transformer to generate a high-voltage transient waveform. The amplitude of the transient waveform is shown below as a square wave signal: Where T is the square wave signal with a period of 0.1 ms, and t is the time axis. The waveform on the load is as follows: Figure 10 As shown, the voltage exhibits a periodic variation from 540V to 549.901V. It is precisely through the control of the graphical program and the coordination of the hardware in this solution that the device outputs... Figure 10 The high-voltage transient waveform shown is shown.

[0079] The specific implementation of each step can be found in the description of the above device, and will not be repeated here.

[0080] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. A device for generating high-voltage transient waveforms, characterized in that, The device includes a signal source, a switching device, a power supply A, a power supply B, a coupling transformer, and a load. The voltage output of power supply B is supplied to the load to provide the rated voltage. Under the control of a graphical program, the signal source provides a trigger signal to the switching device to control the switching device to turn on and off. Under the control of switching devices, power supply A superimposes transient voltage onto the load terminals through a coupling transformer to generate a high-voltage transient waveform; power supply B has a voltage of 270-540V DC.

2. The generating apparatus according to claim 1, characterized in that, Under the control of a graphical program, the signal source provides trigger signals to the switching devices to control their on / off states, including: The computer accesses the VISA serial port via a network cable through a graphical program. The output signal of the VISA serial port control signal source is a PWM square wave signal, and the output is enabled in the output program of the signal source. The PWM square wave signal controls the switching devices to turn on and off.

3. The generating apparatus according to claim 2, characterized in that, Before using a graphical program to control the signal source, set the IP addresses of the signal source and the computer so that the signal source and the computer are on the same local area network.

4. The generating apparatus according to any one of claims 1 to 3, characterized in that, The graphical program is implemented using the LabVIEW language, and the library functions corresponding to the signal sources are deployed in the LabVIEW library file.

5. The generating apparatus according to claim 1, characterized in that, The switching device is a MOS device.

6. The generating apparatus according to claim 5, characterized in that, The MOS device is a B2M030120H silicon carbide MOS transistor; the signal output of the signal source is connected between the gate and source of the B2M030120H silicon carbide MOS transistor, and the load is connected between the drain and source of the B2M030120H silicon carbide MOS transistor.

7. The generating apparatus according to claim 1, characterized in that, The switching time between the voltages of power supply A and power supply B is less than the order of milliseconds.

8. The generating apparatus according to any one of claims 1 and 7, characterized in that, The voltage of power supply A is determined according to industry standards for transient voltage values, and the voltage output by the signal source is 0-3V.

9. The generating apparatus according to any one of claims 1 to 3, 5 to 7, characterized in that, If the turns ratio of the coupling transformer is 1:1, then the primary side of the coupling transformer uses two cables wound in parallel on a magnetic ring, and the secondary side uses a single-coil output winding method.

10. A method for constructing a high-voltage transient waveform, characterized in that, The device for generating high-voltage transient waveforms, as described above, includes: The voltage of power supply B is output to the load to provide the rated voltage; the voltage of power supply B is 270-540V DC. The signal source is controlled by a graphical program to output a square wave pulsating signal; the voltage output by the signal source is 0-3V; the amplitude of the square wave pulsating signal is 0-10V; the duty cycle of the square wave pulsating signal is 50%; and the period of the square wave pulsating signal is 0.1ms. The switching device is controlled by the output signal of the signal source. The turn-on threshold of the MOSFET is 2.3 to 3.5V. When the switching device is turned on, the transient voltage of power supply A is superimposed on the load terminals through the coupling transformer to generate a high-voltage transient waveform; the amplitude of the transient waveform is: Where T is the square wave signal period of 0.1ms, and t is the time axis.

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