CN113991986A - High-voltage square wave pulse power supply with accurate continuous frequency modulation - Google Patents
High-voltage square wave pulse power supply with accurate continuous frequency modulation Download PDFInfo
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- CN113991986A CN113991986A CN202111423100.1A CN202111423100A CN113991986A CN 113991986 A CN113991986 A CN 113991986A CN 202111423100 A CN202111423100 A CN 202111423100A CN 113991986 A CN113991986 A CN 113991986A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
- H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/38—Means for preventing simultaneous conduction of switches
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
Abstract
The invention discloses a high-voltage square wave pulse power supply with accurate and continuous frequency modulation, which consists of an air switch, a voltage regulator, a power frequency transformer, a rectifier filter, an IGBT full-bridge inversion unit, a square wave pulse transformer, a human-computer interface and an IGBT driving unit; the IGBT full-bridge inverter unit consists of 4 field effect transistors V1-V4; the IGBT driving unit consists of a programmable controller, a double-circuit dead zone generating circuit and 4 drivers. The programmable controller outputs a square wave pulse signal with continuously and accurately adjustable frequency, two paths of complementary driving signals with dead zones are generated through a dead zone generating chip, and the complementary driving signals drive an inverter bridge consisting of high-power IGBTs through an isolation driving chip, so that the frequency is automatically and continuously adjustable within a wide range of 1 kHz-20 kHz or is stably output under a certain fixed frequency.
Description
Technical Field
The invention relates to the technical field of power supplies, in particular to a high-voltage square wave pulse power supply with accurate continuous frequency modulation.
Background
The high-voltage square wave pulse power supply regulates the voltage of a power grid through a voltage regulator, isolates and boosts the voltage through a transformer, rectifies the voltage and filters the voltage into direct current voltage, then an inversion full bridge is formed by four high-power IGBTs, the direct current voltage is inverted into square wave pulse voltage, and the square wave pulse voltage is boosted to a required voltage value through a square wave pulse transformer. The high-voltage square wave pulse power supply is mainly used for evaluating the electric service life of a variable frequency motor insulation structure used in the fields of motor traction, wind power generation, new energy automobiles and the like. During testing, the high-voltage square wave pulse power supply starts to be boosted and regulated from zero by the voltage regulator, stops regulating the voltage after reaching the voltage value required by the test through rectification, inversion and boosting, keeps the voltage regulating position unchanged, and ends the test until the sample is damaged or the preset test time is reached. The required peak-to-peak voltage and frequency of the test vary according to the type of sample. However, the current high-voltage square-wave pulse power supply has the problems of difficulty in automatically adjusting the frequency in a wide range and poor stability, so that the experimental result of the electrical life evaluation is influenced.
Disclosure of Invention
The invention aims to solve the problems that the wide-range automatic frequency adjustment of the conventional high-voltage square wave pulse power supply is difficult and the stability is poor, and provides a high-voltage square wave pulse power supply with accurate and continuous frequency adjustment.
In order to solve the problems, the invention is realized by the following technical scheme:
a high-voltage square wave pulse power supply with accurate and continuous frequency modulation comprises an air switch, a voltage regulator, a power frequency transformer, a rectifier filter, an IGBT full-bridge inversion unit, a square wave pulse transformer, a human-computer interface and an IGBT driving unit; the IGBT full-bridge inverter unit consists of 4 field effect transistors V1-V4; the IGBT driving unit consists of a programmable controller, a double-circuit dead zone generating circuit and 4 drivers;
the external power supply is connected with the input side of the voltage regulator through the air switch, the output side of the voltage regulator is connected with the input side of the power frequency transformer, and the output side of the power frequency transformer is connected with the input positive end and the input negative end of the rectifier filter; the positive output end of the rectifying filter is connected with the drain electrode of the field-effect tube V1 and the drain electrode of the field-effect tube V3, and the negative output end of the rectifying filter is connected with the source electrode of the field-effect tube V4 and the source electrode of the field-effect tube V2; the source electrode of the field-effect tube V3 and the drain electrode of the field-effect tube V2 are connected with the positive end of the input side of the square wave pulse transformer, and the source electrode of the field-effect tube V1 and the drain electrode of the field-effect tube V4 are connected with the negative end of the input side of the square wave pulse transformer; the output side of the square wave pulse transformer is connected with a sample to be tested; the human-computer interface is connected with the programmable controller, the voltage regulation control end of the programmable controller is connected with the control end of the voltage regulator, and the clock control end of the programmable controller is connected with the input end of the double-circuit dead zone generating circuit; the Q' output end of the double-circuit dead zone generating circuit is connected with the input ends of the first driver and the second driver, and the Q output end of the double-circuit dead zone generating circuit is connected with the input ends of the third driver and the fourth driver; the input end of the first driver is connected with the grid of the field-effect tube V1, the input end of the second driver is connected with the grid of the field-effect tube V2, the input end of the third driver is connected with the grid of the field-effect tube V3, and the input end of the fourth driver is connected with the grid of the field-effect tube V4.
In the scheme, the double-circuit dead zone generating circuit consists of 6 exclusive-or gates U1A-U1D, U2A-U2B, resistors R1-R2 and capacitors C1-C2; 2 input ends of the exclusive-nor gate U1A and one input end of the exclusive-nor gate U2A are connected to form an input end connected with the double-circuit dead zone generating circuit; the output end of the exclusive nor gate U1A is connected with one end of the resistor R1, 2 input ends of the exclusive nor gate U1B and one input end of the exclusive nor gate U2B; the other end of the resistor R1 is connected with one end of the capacitor C1 and 2 input ends of the XOR gate U2C; the output end of the exclusive-nor gate U2C is connected with the other input end of the exclusive-nor gate U2A; the output end of the exclusive-OR gate U2A forms the Q' output end of the double-circuit dead zone generating circuit; the output end of the exclusive-nor gate U1B is connected with one end of a resistor R2, and the other end of the resistor R2 is connected with one end of a capacitor C2 and 2 input ends of an exclusive-nor gate U1D; the output end of the exclusive-nor gate U1D is connected with the other input end of the exclusive-nor gate U2B; the output end of the exclusive-OR gate U2B forms the Q output end of the double-circuit dead zone generating circuit; the other ends of the capacitor C1 and the capacitor C2 are grounded.
Compared with the prior art, the invention outputs a square wave pulse signal with continuously and accurately adjustable frequency by the programmable controller, generates two paths of complementary driving signals with dead zones by the dead zone generating chip, and drives the inverter bridge consisting of the high-power IGBTs by the complementary driving signals through the isolated driving chip, thereby realizing the automatic continuous adjustment of the frequency in a wide range of 1 kHz-20 kHz or the stable output under a certain fixed frequency.
Drawings
Fig. 1 is a schematic block diagram of a precise continuous frequency-modulated high-voltage square-wave pulse power supply.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to specific examples.
Referring to fig. 1, the high-voltage square-wave pulse power supply with precise and continuous frequency modulation comprises an air switch, a voltage regulator, a power frequency transformer, a rectifier filter, an IGBT full-bridge inversion unit, a square-wave pulse transformer, a human-computer interface and an IGBT driving unit. The IGBT full-bridge inverter unit consists of 4 field effect transistors V1-V4. The IGBT driving unit consists of a programmable controller, a double-circuit dead zone generating circuit and 4 drivers.
The double-circuit dead zone generating circuit consists of 6 exclusive-or gates U1A-U1D, U2A-U2B, resistors R1-R2 and capacitors C1-C2. 2 input ends of the exclusive-nor gate U1A and one input end of the exclusive-nor gate U2A are connected to form an input end of the double-circuit dead zone generating circuit. The output end of the exclusive nor gate U1A is connected with one end of the resistor R1, 2 input ends of the exclusive nor gate U1B and one input end of the exclusive nor gate U2B. The other end of the resistor R1 is connected with one end of the capacitor C1 and 2 input ends of the XOR gate U2C. The output end of the exclusive-nor gate U2C is connected with the other input end of the exclusive-nor gate U2A. The output terminal of the exclusive nor gate U2A forms the Q' output terminal of the two-way dead zone generating circuit. The output end of the exclusive-nor gate U1B is connected with one end of a resistor R2, and the other end of the resistor R2 is connected with one end of a capacitor C2 and 2 input ends of the exclusive-nor gate U1D. The output end of the exclusive-nor gate U1D is connected with the other input end of the exclusive-nor gate U2B. The output terminal of the exclusive nor gate U2B forms the Q output terminal of the two-way dead zone generating circuit. The other ends of the capacitor C1 and the capacitor C2 are grounded.
The external power supply is connected with the input side of the voltage regulator through the air switch, the output side of the voltage regulator is connected with the input side of the power frequency transformer, and the output side of the power frequency transformer is connected with the input positive end and the input negative end of the rectifier filter. The positive output end of the rectifying filter is connected with the drain electrode of the field-effect tube V1 and the drain electrode of the field-effect tube V3, and the negative output end of the rectifying filter is connected with the source electrode of the field-effect tube V4 and the source electrode of the field-effect tube V2. The source electrode of the field-effect transistor V3 and the drain electrode of the field-effect transistor V2 are connected with the positive end of the input side of the square wave pulse transformer, and the source electrode of the field-effect transistor V1 and the drain electrode of the field-effect transistor V4 are connected with the negative end of the input side of the square wave pulse transformer. The output side of the square wave pulse transformer is connected with a sample to be tested. The human-computer interface is connected with the programmable controller, the voltage regulation control end of the programmable controller is connected with the control end of the voltage regulator, and the clock control end of the programmable controller is connected with the input end of the double-circuit dead zone generating circuit. And the Q' output end of the double-circuit dead zone generating circuit is connected with the input ends of the first driver and the second driver, and the Q output end of the double-circuit dead zone generating circuit is connected with the input ends of the third driver and the fourth driver. The input end of the first driver is connected with the grid of the field-effect tube V1, the input end of the second driver is connected with the grid of the field-effect tube V2, the input end of the third driver is connected with the grid of the field-effect tube V3, and the input end of the fourth driver is connected with the grid of the field-effect tube V4.
The IGBT driving unit outputs a corresponding square wave pulse string according to a frequency value input by a human-computer interface through a high-speed pulse generator of a programmable controller, the square wave pulse generates two paths of pulse driving signals with dead zones and opposite phases through a two-path dead zone circuit, the two paths of pulse driving signals with the dead zones and the opposite phases respectively drive four IGBTs of an IGBT full-bridge inversion unit through 4 drivers, so that direct current voltage on a bridge circuit can be inverted into square wave pulse voltage, and the pulse voltage is boosted to a required voltage value through a high-power high-voltage square wave pulse transformer. The square wave voltage frequency of the high-voltage square wave pulse power supply is required to be continuously adjustable from 1kHz to 20kHz, and is required to have a rising edge as fast as possible, and is required to be stable and reliable when a certain frequency is output. The programmable controller adopts a built-in crystal oscillator to generate a reference clock, the pulse output end can generate square wave pulse with accurate single frequency point, and the automatic continuous frequency sweeping function at 1 kHz-20 kHz can be conveniently realized, so that the problems that an oscillation pulse signal generator formed by a traditional voltage regulation chip changes along with the temperature drift of an external RC and the automatic frequency sweeping is inconvenient are solved.
The performance of the invention was analyzed experimentally as follows:
1. the method comprises the steps of averagely dividing 20 coil samples with the same capacity and voltage-withstanding grade into A, B, C, D4 groups, setting rated test voltage of each group to be 10.00kV, setting test time to be 100h, adopting test frequency of 1kHz for A, B group samples, adopting test frequency of 20kHz for C, D group samples, adopting SG A, C group samples to generate a test device for generating complementary driving signals for testing A, C group samples, adopting the power supply device disclosed by the invention for testing B, D group samples, and simultaneously starting the test under the condition that other conditions are consistent.
2. The group A adopts a testing device for generating a complementary driving signal by SG3525 to test, the test is started, the system automatically boosts to a rated voltage of 10kV, a knob of a 20k omega potentiometer is manually adjusted to change a frequency signal generated by SG3525 to 1kHz, the actual display value of an oscilloscope fluctuates between 1kHz and 1.02kHz, and the visual inspection resolution is about 0.02 kHz. The frequency is recorded every 5 hours, and the fluctuation range of the statistical frequency value after the test of 100 hours is 0.98 kHz-1.04 kHz.
3. The group C adopts a test device which generates a complementary driving signal by SG3525 to carry out test, the test is started, the system automatically boosts to a rated voltage of 10kV, a 20k omega potentiometer knob is manually adjusted to change a frequency signal generated by SG3525 to 20kHz, the actual display value fluctuates between 19.99kHz and 20.03kHz, and the visual inspection of the resolution ratio is about 0.02 kHz. The frequency is recorded every 5 hours, and the fluctuation range of the statistical frequency value after the test of 100 hours is 19.95 kHz-20.12 kHz.
4. The group B adopts the test device to carry out the test, the test is started, the system automatically boosts to the rated voltage of 10kV, the 1kHz is manually input on the screen, and the actual display value of the oscilloscope is 1.00kHz without fluctuation. The frequency was recorded every 5 hours, and the statistical frequency value fluctuation range was 1.00kHz after the 100-hour test was completed, with no fluctuation.
5. The group D adopts the test device to carry out the test, the test is started, the system automatically boosts to the rated voltage of 10kV, the 20kHz is manually input on the screen, and the actual display value of the oscilloscope is 20.00kHz without fluctuation. The frequency is recorded every 5 hours, and the fluctuation range of the statistical frequency value after the test of 100 hours is 20.00 kHz-20.01 kHz.
Through monitoring and analysis, the traditional test device for generating complementary driving signals by adopting SG3525 has the defects that the temperature drift of the resistor and the capacitor of an adjusting device is greatly influenced, and the adjusting range and the resolution of frequency are influenced by adjusting the resistance value of the resistor. The square wave pulse signal output by the programmable controller can be randomly set in a wide range and accurately output, and the output frequency is stable and reliable.
The invention develops a high-voltage square wave pulse power supply with wide-range accurate frequency modulation, which has the characteristics of continuous adjustability in a wide frequency range and stable output frequency, wherein the output frequency is continuously adjustable in a range of 1 kHz-20 kHz, and the precision and the stability are within 0.1 percent.
It should be noted that, although the above-mentioned embodiments of the present invention are illustrative, the present invention is not limited thereto, and thus the present invention is not limited to the above-mentioned embodiments. Other embodiments, which can be made by those skilled in the art in light of the teachings of the present invention, are considered to be within the scope of the present invention without departing from its principles.
Claims (2)
1. A high-voltage square wave pulse power supply with accurate and continuous frequency modulation is characterized by comprising an air switch, a voltage regulator, a power frequency transformer, a rectifier filter, an IGBT full-bridge inversion unit, a square wave pulse transformer, a human-computer interface and an IGBT driving unit; the IGBT full-bridge inverter unit consists of 4 field effect transistors V1-V4; the IGBT driving unit consists of a programmable controller, a double-circuit dead zone generating circuit and 4 drivers;
the external power supply is connected with the input side of the voltage regulator through the air switch, the output side of the voltage regulator is connected with the input side of the power frequency transformer, and the output side of the power frequency transformer is connected with the input positive end and the input negative end of the rectifier filter; the positive output end of the rectifying filter is connected with the drain electrode of the field-effect tube V1 and the drain electrode of the field-effect tube V3, and the negative output end of the rectifying filter is connected with the source electrode of the field-effect tube V4 and the source electrode of the field-effect tube V2; the source electrode of the field-effect tube V3 and the drain electrode of the field-effect tube V2 are connected with the positive end of the input side of the square wave pulse transformer, and the source electrode of the field-effect tube V1 and the drain electrode of the field-effect tube V4 are connected with the negative end of the input side of the square wave pulse transformer; the output side of the square wave pulse transformer is connected with a sample to be tested;
the human-computer interface is connected with the programmable controller, the voltage regulation control end of the programmable controller is connected with the control end of the voltage regulator, and the clock control end of the programmable controller is connected with the input end of the double-circuit dead zone generating circuit; the Q' output end of the double-circuit dead zone generating circuit is connected with the input ends of the first driver and the second driver, and the Q output end of the double-circuit dead zone generating circuit is connected with the input ends of the third driver and the fourth driver; the input end of the first driver is connected with the grid of the field-effect tube V1, the input end of the second driver is connected with the grid of the field-effect tube V2, the input end of the third driver is connected with the grid of the field-effect tube V3, and the input end of the fourth driver is connected with the grid of the field-effect tube V4.
2. The precise continuous frequency modulation high-voltage square wave pulse power supply as claimed in claim 1, wherein the two-way dead zone generating circuit is composed of 6 exclusive or gates U1A-U1D, U2A-U2B, resistors R1-R2 and capacitors C1-C2;
2 input ends of the exclusive-nor gate U1A and one input end of the exclusive-nor gate U2A are connected to form an input end connected with the double-circuit dead zone generating circuit; the output end of the exclusive nor gate U1A is connected with one end of the resistor R1, 2 input ends of the exclusive nor gate U1B and one input end of the exclusive nor gate U2B; the other end of the resistor R1 is connected with one end of the capacitor C1 and 2 input ends of the XOR gate U2C; the output end of the exclusive-nor gate U2C is connected with the other input end of the exclusive-nor gate U2A; the output end of the exclusive-OR gate U2A forms the Q' output end of the double-circuit dead zone generating circuit; the output end of the exclusive-nor gate U1B is connected with one end of a resistor R2, and the other end of the resistor R2 is connected with one end of a capacitor C2 and 2 input ends of an exclusive-nor gate U1D; the output end of the exclusive-nor gate U1D is connected with the other input end of the exclusive-nor gate U2B; the output end of the exclusive-OR gate U2B forms the Q output end of the double-circuit dead zone generating circuit; the other ends of the capacitor C1 and the capacitor C2 are grounded.
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| CN202111423100.1A CN113991986A (en) | 2021-11-26 | 2021-11-26 | High-voltage square wave pulse power supply with accurate continuous frequency modulation |
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| CN202111423100.1A CN113991986A (en) | 2021-11-26 | 2021-11-26 | High-voltage square wave pulse power supply with accurate continuous frequency modulation |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114944747A (en) * | 2022-06-08 | 2022-08-26 | 哈尔滨理工大学 | Novel carborundum MOSFET drive circuit |
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2021
- 2021-11-26 CN CN202111423100.1A patent/CN113991986A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114944747A (en) * | 2022-06-08 | 2022-08-26 | 哈尔滨理工大学 | Novel carborundum MOSFET drive circuit |
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