CN112838767A - Hybrid three-level bidirectional DC-DC converter and neutral point voltage balance control method thereof - Google Patents
Hybrid three-level bidirectional DC-DC converter and neutral point voltage balance control method thereof Download PDFInfo
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- CN112838767A CN112838767A CN202110291918.6A CN202110291918A CN112838767A CN 112838767 A CN112838767 A CN 112838767A CN 202110291918 A CN202110291918 A CN 202110291918A CN 112838767 A CN112838767 A CN 112838767A
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- 230000002457 bidirectional effect Effects 0.000 title claims abstract description 39
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- 230000007935 neutral effect Effects 0.000 title claims abstract description 9
- 230000010363 phase shift Effects 0.000 claims abstract description 104
- 239000003990 capacitor Substances 0.000 claims abstract description 80
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- 239000008384 inner phase Substances 0.000 claims description 33
- 238000004804 winding Methods 0.000 claims description 20
- 238000004590 computer program Methods 0.000 claims description 11
- 238000004364 calculation method Methods 0.000 claims description 9
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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
- H02M3/00—Conversion of DC power input into DC power output
- H02M3/22—Conversion of DC power input into DC power output with intermediate conversion into AC
- H02M3/24—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
- H02M3/28—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC
- H02M3/325—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
- H02M3/33584—Bidirectional converters
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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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Abstract
The invention discloses a mixed three-level bidirectional DC-DC converter, the topological structure mainly comprises: a direct current power supply, a three-level structure and an H-bridge structure. The topology of the converter comprises a three-level structure, so that the voltage stress of the switching tube can be reduced, and the voltage of a direct current side can be improved. The phase shift addition duty ratio control is realized by increasing a phase shift angle, so that different voltage waveforms are output by the AC side of the converter, and the control is more flexible. The neutral point voltage balance control method can effectively solve the problem of neutral point clamping capacitor voltage deviation of a three-level structure, thereby avoiding the problems of increased capacitance loss, reduced service life, increased output waveform harmonic content and the like and ensuring the long-term reliable operation of the hybrid three-level bidirectional DC/DC converter.
Description
Technical Field
The invention belongs to the technical field of power electronics, and particularly relates to a hybrid three-level bidirectional DC-DC converter and a midpoint voltage balance control method of the hybrid three-level bidirectional DC-DC converter.
Background
The isolated bidirectional DC/DC converter is usually a bidirectional full-bridge circuit structure and consists of two H-bridges, a high-frequency transformer and two direct-current voltage-stabilizing capacitors. Although the topological structure can realize electric isolation and bidirectional energy flow, the voltage stress of the switching tube of the structure is equal to the input or output voltage. Therefore, the higher the input or output voltage is, the higher the withstand voltage value of the switching tube is required to be, so that only the power device with higher withstand voltage level can be selected to meet the design requirement, which inevitably increases the system cost and reduces the efficiency and reliability of the system.
The traditional phase shift control of the hybrid three-level bidirectional DC/DC converter is realized by changing the phase shift angle between a three-level full bridge and an H bridge, the soft switching range is reduced when the voltages at two ends of the transformer are not matched by the control method, the effective value of the current is larger, the loss of the converter is increased, and the efficiency is reduced.
In circuit topologies with cascaded capacitors, midpoint voltage balancing has been the focus of research. The problem of unbalanced voltage at two ends of the capacitor can occur under the conditions that the charging voltage between the cascaded capacitors is different, or the switching-on time of the switching tube is delayed, and the like. In three-phase inverters, midpoint voltage balancing has been studied intensively, but in dc converters, the problem has been studied little.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, provides a hybrid three-level bidirectional DC-DC converter, and solves the problems of high requirement on the withstand voltage value of a switching tube, high system cost and low efficiency of the traditional bidirectional transformer.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows.
In a first aspect, the present invention provides a hybrid three-level bidirectional DC-DC converter comprising: the circuit comprises a direct-current power supply, a voltage division capacitor circuit, a three-level circuit, a transformer, an H-bridge circuit and a load resistor;
the voltage division capacitor circuit comprises a first capacitor and a second capacitor which are connected in series; two ends are respectively connected with the positive end and the negative end of the direct current power supply; the series midpoint of the first capacitor and the second capacitor is used as a voltage division end of the voltage division capacitor circuit;
the three-level circuit comprises two ends of a first half-bridge arm and a second half-bridge arm which are connected in parallel, wherein the two ends of the first half-bridge arm and the second half-bridge arm are respectively connected with the positive end and the negative end of a direct-current power supply; the input end of the first half-bridge arm and the input end of the second half-bridge arm are respectively connected with the voltage dividing end of the voltage dividing capacitor circuit; the middle point of the first half-bridge arm and the center of the second half-bridge arm are respectively connected with two ends of a first winding of the transformer;
one end of a second winding of the transformer is connected with a first inductor in series and then is connected with a first input end of the H-bridge circuit, and the other end of the second winding of the transformer is connected with a second input end of the H-bridge circuit;
the middle points of two bridge arms of the H-bridge circuit are connected with a third capacitor and a load resistor which are connected in parallel.
Optionally, the three-level circuit includes: the first diode, the second diode, the third diode, the fourth diode, the first switching tube, the second switching tube, the third switching tube, the fourth switching tube, the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube;
the first half-bridge arm is formed by a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first diode and a second diode, and the second half-bridge arm is formed by a fifth switch tube, a sixth switch tube, a seventh switch tube, an eighth switch tube, a third diode and a fourth diode;
the first switching tube, the second switching tube, the third switching tube and the fourth switching tube are sequentially connected in series in a forward direction, and two ends of the first switching tube, the second switching tube, the third switching tube and the fourth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply; the first diode and the second diode are connected in series in the forward direction, and two ends of the first diode and the second diode are respectively connected with the series midpoint of the first switching tube and the second switching tube and the series midpoint of the third switching tube and the fourth switching tube; the series midpoint of the first diode and the second diode is used as the input end of a first half-bridge arm and is connected with the voltage dividing end of the voltage dividing capacitor circuit;
the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube are sequentially connected in series in the forward direction, and two ends of the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply; the third diode and the fourth diode are connected in series in the forward direction, and two ends of the third diode and the fourth diode are respectively connected with the series midpoint of the fifth switching tube and the sixth switching tube and the series midpoint of the seventh switching tube and the eighth switching tube; the series midpoint of the third diode and the fourth diode is used as the input end of the second half-bridge arm and is connected with the voltage dividing end of the voltage dividing capacitor circuit;
the series midpoint of the second switching tube and the third switching tube is used as the midpoint of the first half-bridge arm and is connected with one end of a first winding of the transformer; and the serial midpoint of the sixth switching tube and the seventh switching tube is used as the center of the second half-bridge arm and is connected with the other end of the first winding of the transformer.
Optionally, the method further includes:
when the first to third internally shifted phase angles are zero, the midpoint voltage outputs two-level alternating-current voltage;
when the first internal phase shift angle is not zero and the second and third internal phase shift angles are zero, the midpoint voltage outputs three-level alternating current voltage;
when the first and second internal phase shift angles are not zero and the third phase shift angle is zero, the midpoint voltage outputs four-level alternating current voltage;
when the first to third internally shifted phase angles are all zero, the midpoint voltage outputs an alternating current voltage with five levels;
the first internal phase shifting angle is a phase shifting angle between driving signals of the first switching tube and the third switching tube, the second internal phase shifting angle is a phase shifting angle between driving signals of the first switching tube and the seventh switching tube, and the third internal phase shifting angle is a phase shifting angle between the second switching tube and the eighth switching tube.
Optionally, the H-bridge circuit includes: a ninth switching tube, a tenth switching tube, an eleventh switching tube and a twelfth switching tube;
the ninth switching tube and the tenth switching tube are connected in series in the forward direction, the series midpoint of the ninth switching tube and the tenth switching tube is used as a first input end of the H-bridge circuit, and the ninth switching tube and the tenth switching tube are connected with one end of a second winding of the transformer after being connected with the first inductor in series;
the eleventh switching tube and the twelfth switching tube are connected in series in the forward direction, and the series midpoint of the eleventh switching tube and the twelfth switching tube is used as the second input end of the H-bridge circuit and is connected with the other end of the second winding of the transformer;
the connection middle points of the ninth switching tube and the eleventh switching tube as well as the tenth switching tube and the twelfth switching tube are used as the middle points of two bridge arms of the H-bridge circuit and are connected with the third capacitor and the load resistor which are connected in parallel.
Optionally, the method further includes:
when the fourth internal phase shift angle is zero, the midpoint voltage outputs two-level alternating-current voltage;
when the fourth internal phase shift angle is not zero, the midpoint voltage outputs three-level alternating-current voltage;
and the fourth internal phase shift angle is a phase shift angle between driving signals of the ninth switching tube and the twelfth switching tube.
In a second aspect, in order to solve the problem of midpoint voltage balance of the hybrid three-level bidirectional DC/DC converter, the present invention provides a method for controlling midpoint voltage balance of the hybrid three-level bidirectional DC/DC converter, including the following steps:
acquiring three-level circuit output power, H-bridge circuit output power, direct-current power supply voltage and load resistance voltage when the converter works in a steady state;
calculating a first inner shift phase angle, a second inner shift phase angle, a third inner shift phase angle, a fourth inner shift phase angle and a first outer shift phase angle when the converter works in a steady state based on the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load, wherein the first inner shift phase angle, the second inner shift phase angle, the third inner shift phase angle, the fourth inner shift phase angle and the first outer shift phase angle are used as a first initial inner shift phase angle, a second initial inner shift phase angle, a third initial inner shift phase angle, a fourth;
collecting a first capacitor voltage and a second capacitor voltage and making a difference between the first capacitor voltage and the second capacitor voltage; performing PI adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
taking the sum of the voltage compensation angle and each initial internal shift phase angle and the first initial external shift phase angle as each internal shift phase angle and the first external shift phase angle;
and determining a driving signal corresponding to the switching tube based on each internal phase shifting angle and the first external phase shifting angle so as to enable the voltages of the two capacitors to be equal and realize midpoint voltage balance.
In a third aspect, the present invention further provides a midpoint voltage balance control device of a hybrid three-level bidirectional DC/DC converter, including:
the data acquisition module is used for acquiring the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load resistor when the converter works in a steady state;
the initial phase shift angle calculation module is used for calculating and obtaining a first inner phase shift angle, a second inner phase shift angle, a third inner phase shift angle, a fourth inner phase shift angle and a first outer phase shift angle when the converter works in a stable state based on the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of a load, and the first inner phase shift angle, the second inner phase shift angle, the third inner phase shift angle, the fourth inner phase shift angle and the first outer phase shift angle are used as a first initial inner phase shift angle, a second initial inner phase shift angle, a third initial inner phase;
the compensation angle calculation module is used for acquiring the first capacitor voltage and the second capacitor voltage and performing difference on the first capacitor voltage and the second capacitor voltage; performing PI adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
the driving signal calculation module is used for taking the sum of the voltage compensation angle and each initial inward shift phase angle and the first initial outward shift phase angle as each inward shift phase angle and the first outward shift phase angle; and determining a driving signal corresponding to the switching tube based on each internal phase shifting angle and the first external phase shifting angle so as to enable the voltages of the two capacitors to be equal and realize midpoint voltage balance.
In a fourth aspect, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which when executed by a processor, implements the midpoint voltage balance control method of the hybrid three-level bidirectional DC/DC converter according to the second aspect.
Compared with the prior art, the invention has the following beneficial effects:
1) the voltage stress of the switching tube can be reduced by the three-level structure side, and the voltage of the direct current side is improved; the output voltage can be adjusted more flexibly by phase-shifting and duty ratio control, and the control is simple and convenient;
2) the neutral point voltage balance control method can effectively solve the problem of neutral point clamping capacitor voltage deviation of a three-level structure, thereby avoiding the problems of increased capacitance loss, reduced service life, increased output waveform harmonic content and the like, and ensuring the long-term reliable operation of the hybrid three-level bidirectional DC/DC converter.
Drawings
FIG. 1 is a schematic diagram of the circuit configuration of the present invention;
fig. 2 is a specific working example of the hybrid three-level bidirectional DC/DC converter of the present invention, in which the voltages of the first inductor and the first inductor are respectively the bridge arm midpoint voltage of the three-level structure, the bridge arm midpoint voltage of the H-bridge, and the current of the first inductor from top to bottom;
fig. 3 is a control block diagram of the midpoint voltage balance control method of the hybrid three-level bidirectional DC/DC converter of the present invention.
Description of reference numerals:
1-a direct current power supply; 2-a first capacitance; 3-a second capacitance; 4-a first diode; 5-a second diode; 6-a first switch tube; 7-a second switching tube; 8-a third switching tube; 9-a fourth switching tube; 10-a third diode; 11-a fourth diode; 12-a fifth switching tube; 13-a sixth switching tube; 14-seventh switching tube; 15-eighth switching tube; 16-a first winding; 17-a second winding; 18-a first inductance; 19-a ninth switching tube; 20-tenth switching tube; 21-eleventh switching tube; 22-a twelfth switching tube; 23-a third capacitance; 24-load resistance.
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
Example 1
In an embodiment of the present invention, a hybrid three-level bidirectional DC/DC converter is shown in fig. 1, and includes: the circuit comprises a direct current power supply 1, a voltage division capacitor circuit, a three-level circuit, a transformer, an H-bridge circuit and a load resistor 24;
the voltage division capacitor circuit comprises a first capacitor 2 and a second capacitor 3 which are connected in series; two ends of the voltage division capacitor circuit are respectively connected with the positive end and the negative end of the direct current power supply 1;
the three-level circuit includes: the circuit comprises a first diode 4, a second diode 5, a third diode 10, a fourth diode 11, a first switch tube 6, a second switch tube 7, a third switch tube 8, a fourth switch tube 9, a fifth switch tube 12, a sixth switch tube 13, a seventh switch tube 14 and an eighth switch tube 15.
A first half-bridge arm is formed by a first switch tube 6, a second switch tube 7, a third switch tube 8, a fourth switch tube 9, a first diode 4 and a second diode 5, and a second half-bridge arm is formed by a fifth switch tube 12, a sixth switch tube 13, a seventh switch tube 14, an eighth switch tube 15, a third diode 10 and a fourth diode 11;
the first switching tube 6, the second switching tube 7, the third switching tube 8 and the fourth switching tube 9 are sequentially connected in series in the forward direction, and two ends of the first switching tube, the second switching tube, the third switching tube and the fourth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply 1; the first diode 4 and the second diode 5 are connected in series in the forward direction, and two ends of the first diode and the second diode are respectively connected with the series midpoint of the first switch tube 6 and the second switch tube 7 and the series midpoint of the third switch tube 8 and the fourth switch tube 9; the series midpoint (as the input end of a first half-bridge arm) of the first diode 4 and the second diode 5 is connected with the series midpoint (as the voltage dividing end of the voltage dividing capacitor circuit) of the first capacitor 2 and the second capacitor 3;
a fifth switching tube 12, a sixth switching tube 13, a seventh switching tube 14 and an eighth switching tube 15 are sequentially connected in series in the forward direction, and two ends of the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply 1; the third diode 10 and the fourth diode 11 are connected in series in the forward direction, and two ends of the third diode are respectively connected with the series midpoint of the fifth switching tube 12 and the sixth switching tube 13 and the series midpoint of the seventh switching tube 14 and the eighth switching tube 15; the series midpoint (as the input end of the second half-bridge arm) of the third diode 10 and the fourth diode 11 is connected with the series midpoint (as the voltage dividing end of the voltage dividing capacitor circuit) of the first capacitor 2 and the second capacitor 3;
the series midpoint (as the midpoint output end of the first half-bridge arm) of the second switching tube 7 and the third switching tube 8 is connected with one end of a first winding 16 of the transformer; the serial connection midpoint of the sixth switching tube 13 and the seventh switching tube 14 (as the midpoint output end of the second half-bridge arm) is connected to the other end of the first winding 16 of the transformer;
the H-bridge circuit includes: a ninth switching tube 19, a tenth switching tube 20, an eleventh switching tube 21 and a twelfth switching tube 22;
the ninth switching tube 19 and the tenth switching tube 20 are connected in series in the forward direction, and the series midpoint (as the first input end of the H-bridge circuit) of the ninth switching tube 19 and the tenth switching tube 20 is connected in series with the first inductor 18 and then connected with one end of the second winding 17 of the transformer;
the eleventh switch tube 21 and the twelfth switch tube 22 are connected in series in the forward direction, and the series midpoint (as the second input end of the H-bridge circuit) of the eleventh switch tube 21 and the twelfth switch tube 22 is connected to the other end of the second winding 17 of the transformer;
the third capacitor 23 and the load resistor 24 connected in parallel are connected to both ends of the H-bridge circuit.
The direct-current side of the three-level structure of the hybrid three-level bidirectional DC/DC converter can be connected with a medium-high voltage direct-current power supply, and two capacitors are connected in parallel at two ends of the direct-current power supply for voltage division, so that the voltage stress borne by a switch tube in the three-level structure is half of the voltage of the direct-current side. For a three-level circuit topological structure, the basic working principle is that different alternating-current voltages are output from the middle points of two bridge arms by controlling the duty ratio of each switching tube driving signal and the phase shift angle between the switching tube driving signals.
The driving signal of the third switch tube 8 is complementary to the driving signal of the first switch tube 6; the driving signal of the second switch tube 7 is complementary to the driving signal of the fourth switch tube 9; the driving signal of the fifth switch tube 12 is complementary to the driving signal of the seventh switch tube 14; the driving signal of the sixth switching tube 13 is complementary to the driving signal of the eighth switching tube 15. The first internal phase shift angle is a phase shift angle between driving signals of the first switch tube 6 and the third switch tube 8, the second internal phase shift angle is a phase shift angle between driving signals of the first switch tube 6 and the seventh switch tube 14, and the third internal phase shift angle is a phase shift angle between the second switch tube 7 and the eighth switch tube 15. The midpoint voltage output of the three-phase bridge circuit includes alternating voltages of two, three, four and five levels. The two levels are respectively positive direct current voltage and negative direct current voltage, the three levels are respectively positive direct current voltage, negative direct current voltage and zero level, the four levels are respectively half of positive direct current voltage and half of negative direct current voltage and negative direct current voltage, and the five levels are respectively half of positive direct current voltage and positive direct current voltage, half of negative direct current voltage and zero level.
The first to third internal phase shift angles between driving signals of the switching tube are controlled to enable the midpoint voltages of the two bridge arms of the three-level structure to output alternating-current voltages of two levels, three levels, four levels and five levels. The method specifically comprises the following steps:
when the first to third internally shifted phase angles are zero, the midpoint voltage outputs two-level alternating-current voltage;
when the first internal phase shift angle is not zero and the second and third internal phase shift angles are zero, the midpoint voltage outputs three-level alternating current voltage;
when the first and second internal phase shift angles are not zero and the third phase shift angle is zero, the midpoint voltage outputs four-level alternating current voltage;
when the first to third internally shifted phase angles are all zero, the midpoint voltage outputs an alternating current voltage with five levels.
When the first, second, seventh and eighth switching tubes are all conducted, the positive direct-current voltage is obtained;
when the first, second, seventh and eighth switching tubes are all turned off, the negative direct-current voltage is obtained;
when the first switch tube and the second switch tube are switched on, the seventh switch tube and the eighth switch tube are switched off, or when the seventh switch tube and the eighth switch tube are switched on, the first switch tube and the second switch tube are in zero level when switched off;
when the first, second and seventh switching tubes are switched on, the eighth switching tube is switched off, or when the second, seventh and eighth switching tubes are switched on, the first switching tube is switched off and is one half of the positive direct current voltage;
the eighth switching tube is turned on, and when the first, second and seventh switching tubes are turned off or when the first switching tube is turned on, the second, seventh and eighth switching tubes are turned off, the voltage is one half of the negative direct current voltage.
The H bridge direct current side of the hybrid three-level bidirectional DC/DC converter is connected to a load, and the output voltage and power can be adjusted by adjusting the size of the load. For the H-bridge circuit topological structure, the basic working principle is that different alternating-current voltages are output from the middle points of two bridge arms by controlling the duty ratio of each switching tube driving signal and the phase shift angle between the switching tube driving signals.
The driving signal of the ninth switching tube 19 is complementary to the driving signal of the tenth switching tube 20; the driving signal of the eleventh switch tube 21 is complementary to the driving signal of the twelfth switch tube 22, and the fourth internal phase shift angle is a phase shift angle between the driving signals of the ninth switch tube 19 and the twelfth switch tube 22. The midpoint voltage output of the two bridge arms of the H-bridge structure comprises alternating-current voltages of two levels and three levels. The two levels are respectively positive direct current voltage and negative direct current voltage, and the three levels are respectively positive direct current voltage, negative direct current voltage and zero level.
And the fourth internal phase shift angle between the driving signals of the ninth switching tube and the twelfth switching tube is controlled to enable the midpoint voltage of the two bridge arms of the H-bridge structure to output two-level and three-level alternating-current voltages. The method specifically comprises the following steps:
when the fourth internal phase shift angle is zero, the midpoint voltage outputs two-level alternating-current voltage; when the fourth internally shifted phase angle is not zero, the midpoint voltage outputs three-level alternating current voltage.
When the ninth switching tube and the twelfth switching tube are both conducted, the direct current voltage is positive;
when the ninth switching tubes are all turned off, the voltage is negative direct current voltage;
when the ninth switch tube is turned on and the twelfth switch tube is turned off or when the twelfth switch tube is turned on and the ninth switch tube is turned off, the zero level is obtained.
A first outward shift phase angle exists between bridge arms of the three-level structure and the H-bridge structure, and the transmission power can be effectively adjusted by adjusting the magnitude of the first outward shift phase angle.
The working modes of the three-level bidirectional DC-DC converter are divided into two modes, wherein one mode is that energy flows from the high-voltage network side to the low-voltage network side, the high-voltage side three-flat bridge is in an inversion state, the low-voltage network side H bridge circuit is in a rectification state, and a first outward phase shift angle between the high-voltage network side three-flat bridge and the low-voltage network side H bridge circuit is positive; the other is that energy flows from the low-voltage network side to the high-voltage network side, at the moment, the three-flat bridge on the high-voltage network side is in a rectification state, the H-bridge circuit on the low-voltage network side is in an inversion state, and a first outward-shift phase angle between the three-flat bridge on the high-voltage network side and the H-bridge circuit on the low-voltage side is negative. The two operation modes are most different from the positive and negative of the first outward phase angle, the analysis shows the same process, and in order to avoid repetition, the first operation mode is taken as an example for detailed description.
The input of the circuit structure for the hybrid three-level bidirectional DC/DC converter is direct current voltage, multi-level alternating current voltage is generated through the three-level structure, the output of the output port is stable direct current voltage, and the output direct current voltage and power can be adjusted by adjusting the size of a load.
Fig. 2 is a waveform of a working example of the proposed hybrid three-level bidirectional DC/DC converter, where the first waveform is a waveform of a midpoint voltage of a bridge arm of a three-level circuit, and the midpoint voltage is a three-level voltage, and at this time, a first phase shift angle between driving signals of a first switching tube and a seventh switching tube is not zero, and second and third phase shift angles are zero; the second waveform is a voltage waveform of a midpoint of an H bridge arm, wherein the voltage of the midpoint is two-level voltage, and a fourth internal phase shift angle between driving signals of a ninth switching tube and a twelfth switching tube is zero at the moment; at this time, a first phase shift angle between the three-level structure and the H-bridge structure is not zero; the third waveform is the voltage waveform of the first inductor; the fourth waveform is the current waveform of the first inductor.
Example 2
Accordingly, the method for controlling the midpoint voltage balance of the hybrid three-level bidirectional DC/DC converter of the present invention, as shown in fig. 3, includes the following steps:
step 1, firstly, acquiring output power of a three-level circuit, output power of an H-bridge circuit, direct-current power supply voltage and load resistance voltage in a hybrid three-level bidirectional DC/DC converter;
step 2, obtaining a first initial internal phase shift angle, a second initial internal phase shift angle, a third initial internal phase shift angle, a fourth initial internal phase shift angle and a first initial external phase shift angle through an optimization process according to the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load resistor; the first initial internal shift phase angle, the second initial internal shift phase angle, the third initial internal shift phase angle, the fourth initial internal shift phase angle and the first initial external shift phase angle respectively correspond to the first internal shift phase angle, the second internal shift phase angle, the third internal shift phase angle, the fourth internal shift phase angle and the first external shift phase angle when the converter works in a steady state.
The optimization process is to establish a port power model, namely an expression between port power and direct current voltage and between each phase shift angle according to the working waveform of the converter. And obtaining the constraint conditions of power and direct-current voltage according to the optimization target, and combining a power model to obtain an expression of the phase shift angle. The phase shift angle can be calculated by determining the specific values of the direct current voltage and the transmission power and substituting the values into the phase shift angle expression.
Step 3, collecting a first capacitor voltage and a second capacitor voltage, and after filtering and conditioning links, making a difference between the first capacitor voltage and the second capacitor voltage; performing Proportional Integral (PI) adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
the conditioning part is used for processing the sampled signals to make the signals suitable for the input of an A/D converter in the DSP. And selecting a proper resistor according to the acquired voltage grade, and adjusting the sampling signal into a proper voltage signal after the proper resistor passes through the operational amplification circuit. When the first capacitor voltage and the second capacitor voltage have deviation, the difference value of the capacitor voltages is subjected to PI regulation, so that the difference value is gradually reduced until the difference value is zero, and the steady-state error of the system can be reduced. If the PI link is not available, the balance control can not be realized.
Step 4, the voltage compensation angle, each initial internal shift phase angle and the first initial external shift phase angle jointly form each internal shift phase angle and a first external shift phase angle; the method specifically comprises the following steps: the voltage compensation angle and the first initial phase shift angle jointly form (refer to the sum of angles) a first phase shift angle, the voltage compensation angle and the second initial phase shift angle jointly form a second phase shift angle, the voltage compensation angle and the third initial phase shift angle jointly form a third phase shift angle, and the voltage compensation angle and the fourth initial phase shift angle jointly form a fourth phase shift angle; the voltage compensation angle and the first initial outward shift phase angle jointly form a first outward shift phase angle;
and step 5, determining a driving signal corresponding to the switching tube according to the first internal phase shift angle to the fourth internal phase shift angle and the first external phase shift angle, so that the converter works to continuously reduce the difference value of the two capacitor voltages, and finally, the two capacitor voltages are equal to realize midpoint voltage balance.
The driving signals of all the switching tubes are square wave signals, and the driving signals can be obtained by PWM modulation. The phase shift angle corresponds to the delay time of the driving signal of each switching tube, and the delay time = phase shift angle 2 pi/cycle. The on-off of the switch tube can be determined by determining a driving signal (delay time) according to the phase shift angle, so that the converter works to continuously reduce the difference value of the voltages of the two capacitors, and finally the voltages of the two capacitors are equal to realize midpoint voltage balance.
The neutral point voltage balance control method can effectively solve the problem of neutral point clamping capacitor voltage deviation of a three-level structure, thereby avoiding the problems of increased capacitance loss, reduced service life, increased output waveform harmonic content and the like and ensuring the long-term reliable operation of the hybrid three-level bidirectional DC/DC converter.
Example 3
Based on the same inventive concept as embodiment 2, the present invention provides a midpoint voltage balance control device for a hybrid three-level bidirectional DC/DC converter, including:
the data acquisition module is used for acquiring the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load resistor when the converter works in a steady state;
the initial phase shift angle calculation module is used for calculating and obtaining a first inner phase shift angle, a second inner phase shift angle, a third inner phase shift angle, a fourth inner phase shift angle and a first outer phase shift angle when the converter works in a stable state based on the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of a load, and the first inner phase shift angle, the second inner phase shift angle, the third inner phase shift angle, the fourth inner phase shift angle and the first outer phase shift angle are used as a first initial inner phase shift angle, a second initial inner phase shift angle, a third initial inner phase;
the compensation angle calculation module is used for acquiring the first capacitor voltage and the second capacitor voltage and performing difference on the first capacitor voltage and the second capacitor voltage; performing PI adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
the driving signal calculation module is used for taking the sum of the voltage compensation angle and each initial inward shift phase angle and the first initial outward shift phase angle as each inward shift phase angle and the first outward shift phase angle; and determining a driving signal corresponding to the switching tube based on each internal phase shifting angle and the first external phase shifting angle so as to enable the voltages of the two capacitors to be equal and realize midpoint voltage balance.
The specific implementation process of each module of the device refers to each step of the method.
Example 4
Based on the same inventive concept as embodiment 2, a computer-readable storage medium of the present invention, on which a computer program is stored, implements the above-described midpoint voltage balance control method of a hybrid three-level bidirectional DC/DC converter when the computer program is executed by a processor.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (8)
1. A hybrid three-level bidirectional DC-DC converter, comprising: the circuit comprises a direct-current power supply, a voltage division capacitor circuit, a three-level circuit, a transformer, an H-bridge circuit and a load resistor;
the voltage division capacitor circuit comprises a first capacitor and a second capacitor which are connected in series; two ends are respectively connected with the positive end and the negative end of the direct current power supply; the series midpoint of the first capacitor and the second capacitor is used as a voltage division end of the voltage division capacitor circuit;
the three-level circuit comprises two ends of a first half-bridge arm and a second half-bridge arm which are connected in parallel, wherein the two ends of the first half-bridge arm and the second half-bridge arm are respectively connected with the positive end and the negative end of a direct-current power supply; the input end of the first half-bridge arm and the input end of the second half-bridge arm are respectively connected with the voltage dividing end of the voltage dividing capacitor circuit; the middle point of the first half-bridge arm and the center of the second half-bridge arm are respectively connected with two ends of a first winding of the transformer;
one end of a second winding of the transformer is connected with a first inductor in series and then is connected with a first input end of the H-bridge circuit, and the other end of the second winding of the transformer is connected with a second input end of the H-bridge circuit;
the middle points of two bridge arms of the H-bridge circuit are connected with a third capacitor and a load resistor which are connected in parallel.
2. A hybrid three-level bidirectional DC-DC converter as claimed in claim 1, wherein said three-level circuit comprises: the first diode, the second diode, the third diode, the fourth diode, the first switching tube, the second switching tube, the third switching tube, the fourth switching tube, the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube;
the first half-bridge arm is formed by a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first diode and a second diode, and the second half-bridge arm is formed by a fifth switch tube, a sixth switch tube, a seventh switch tube, an eighth switch tube, a third diode and a fourth diode;
the first switching tube, the second switching tube, the third switching tube and the fourth switching tube are sequentially connected in series in a forward direction, and two ends of the first switching tube, the second switching tube, the third switching tube and the fourth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply; the first diode and the second diode are connected in series in the forward direction, and two ends of the first diode and the second diode are respectively connected with the series midpoint of the first switching tube and the second switching tube and the series midpoint of the third switching tube and the fourth switching tube; the series midpoint of the first diode and the second diode is used as the input end of a first half-bridge arm and is connected with the voltage dividing end of the voltage dividing capacitor circuit;
the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube are sequentially connected in series in the forward direction, and two ends of the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube are respectively connected with the positive end and the negative end of the direct-current power supply; the third diode and the fourth diode are connected in series in the forward direction, and two ends of the third diode and the fourth diode are respectively connected with the series midpoint of the fifth switching tube and the sixth switching tube and the series midpoint of the seventh switching tube and the eighth switching tube; the series midpoint of the third diode and the fourth diode is used as the input end of the second half-bridge arm and is connected with the voltage dividing end of the voltage dividing capacitor circuit;
the series midpoint of the second switching tube and the third switching tube is used as the midpoint of the first half-bridge arm and is connected with one end of a first winding of the transformer; and the serial midpoint of the sixth switching tube and the seventh switching tube is used as the center of the second half-bridge arm and is connected with the other end of the first winding of the transformer.
3. A hybrid three-level bidirectional DC-DC converter as recited in claim 2, further comprising:
when the first internally shifted phase angle, the second internally shifted phase angle and the third internally shifted phase angle are all zero, the midpoint voltage outputs alternating-current voltage with two levels;
when the first internal phase shift angle is not zero and the second and third internal phase shift angles are zero, the midpoint voltage outputs three-level alternating current voltage;
when the first and second internal phase shift angles are not zero and the third phase shift angle is zero, the midpoint voltage outputs four-level alternating current voltage;
when the first internally shifted phase angle, the second internally shifted phase angle and the third internally shifted phase angle are all not zero, the midpoint voltage outputs an alternating current voltage with five levels;
the first internal phase shifting angle is a phase shifting angle between driving signals of the first switching tube and the third switching tube, the second internal phase shifting angle is a phase shifting angle between driving signals of the first switching tube and the seventh switching tube, and the third internal phase shifting angle is a phase shifting angle between the second switching tube and the eighth switching tube.
4. A hybrid three-level bidirectional DC-DC converter as claimed in claim 1, wherein said H-bridge circuit comprises: a ninth switching tube, a tenth switching tube, an eleventh switching tube and a twelfth switching tube;
the ninth switching tube and the tenth switching tube are connected in series in the forward direction, the series midpoint of the ninth switching tube and the tenth switching tube is used as a first input end of the H-bridge circuit, and the ninth switching tube and the tenth switching tube are connected with one end of a second winding of the transformer after being connected with the first inductor in series;
the eleventh switching tube and the twelfth switching tube are connected in series in the forward direction, and the series midpoint of the eleventh switching tube and the twelfth switching tube is used as the second input end of the H-bridge circuit and is connected with the other end of the second winding of the transformer;
the connection middle points of the ninth switching tube and the eleventh switching tube as well as the tenth switching tube and the twelfth switching tube are used as the middle points of two bridge arms of the H-bridge circuit and are connected with the third capacitor and the load resistor which are connected in parallel.
5. The hybrid three-level bidirectional DC-DC converter of claim 4, further comprising:
when the fourth internal phase shift angle is zero, the midpoint voltage outputs two-level alternating-current voltage;
when the fourth internal phase shift angle is not zero, the midpoint voltage outputs three-level alternating-current voltage;
and the fourth internal phase shift angle is a phase shift angle between driving signals of the ninth switching tube and the twelfth switching tube.
6. The method for controlling the midpoint voltage balance of a hybrid three-level bidirectional DC/DC converter according to any one of claims 1 to 5, comprising the steps of:
acquiring three-level circuit output power, H-bridge circuit output power, direct-current power supply voltage and load resistance voltage when the converter works in a steady state;
calculating a first inner shift phase angle, a second inner shift phase angle, a third inner shift phase angle, a fourth inner shift phase angle and a first outer shift phase angle when the converter works in a steady state based on the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load, wherein the first inner shift phase angle, the second inner shift phase angle, the third inner shift phase angle, the fourth inner shift phase angle and the first outer shift phase angle are used as a first initial inner shift phase angle, a second initial inner shift phase angle, a third initial inner shift phase angle, a fourth;
collecting a first capacitor voltage and a second capacitor voltage and making a difference between the first capacitor voltage and the second capacitor voltage; performing PI adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
taking the sum of the voltage compensation angle and each initial internal shift phase angle and the first initial external shift phase angle as each internal shift phase angle and the first external shift phase angle; and determining a driving signal corresponding to the switching tube based on each internal phase shifting angle and the first external phase shifting angle so as to enable the voltages of the two capacitors to be equal and realize midpoint voltage balance.
7. A midpoint voltage balance control device of a hybrid three-level bidirectional DC/DC converter is characterized by comprising:
the data acquisition module is used for acquiring the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of the load resistor when the converter works in a steady state;
the initial phase shift angle calculation module is used for calculating and obtaining a first inner phase shift angle, a second inner phase shift angle, a third inner phase shift angle, a fourth inner phase shift angle and a first outer phase shift angle when the converter works in a stable state based on the output power of the three-level circuit, the output power of the H-bridge circuit, the voltage of the direct-current power supply and the voltage of a load, and the first inner phase shift angle, the second inner phase shift angle, the third inner phase shift angle, the fourth inner phase shift angle and the first outer phase shift angle are used as a first initial inner phase shift angle, a second initial inner phase shift angle, a third initial inner phase;
the compensation angle calculation module is used for acquiring the first capacitor voltage and the second capacitor voltage and performing difference on the first capacitor voltage and the second capacitor voltage; performing PI adjustment on the capacitance voltage difference value to obtain a voltage compensation angle;
the driving signal calculation module is used for taking the sum of the voltage compensation angle and each initial inward shift phase angle and the first initial outward shift phase angle as each inward shift phase angle and the first outward shift phase angle; and determining a driving signal corresponding to the switching tube based on each internal phase shifting angle and the first external phase shifting angle so as to enable the voltages of the two capacitors to be equal and realize midpoint voltage balance.
8. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out a method of controlling the neutral voltage balance of a hybrid three-level bidirectional DC/DC converter according to claim 6.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118508760A (en) * | 2024-05-08 | 2024-08-16 | 合肥工业大学 | Heat balance method based on three-phase DC-DC converter |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103051228A (en) * | 2012-12-12 | 2013-04-17 | 江苏大学 | Method and device for balancing neutral point voltage deviation on direct current side of diode-clamped three-level inverter |
| CN103138591A (en) * | 2011-11-24 | 2013-06-05 | 深圳古瑞瓦特新能源有限公司 | Voltage balance control method and device for three-level conversion neutral point, and three-level converter |
| CN111092553A (en) * | 2019-10-21 | 2020-05-01 | 华中科技大学 | A Bidirectional DC/DC Converter Based on Isolated Full-Bridge ANPC and H-Bridge |
| CN112054694A (en) * | 2020-09-16 | 2020-12-08 | 广东电网有限责任公司电力科学研究院 | Bidirectional converter optimization control method and device based on minimum current stress |
| CN112332688A (en) * | 2020-05-28 | 2021-02-05 | 哈尔滨工程大学 | A composite controller for a three-level DC converter and its composite control method and energy control method |
-
2021
- 2021-03-18 CN CN202110291918.6A patent/CN112838767A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103138591A (en) * | 2011-11-24 | 2013-06-05 | 深圳古瑞瓦特新能源有限公司 | Voltage balance control method and device for three-level conversion neutral point, and three-level converter |
| CN103051228A (en) * | 2012-12-12 | 2013-04-17 | 江苏大学 | Method and device for balancing neutral point voltage deviation on direct current side of diode-clamped three-level inverter |
| CN111092553A (en) * | 2019-10-21 | 2020-05-01 | 华中科技大学 | A Bidirectional DC/DC Converter Based on Isolated Full-Bridge ANPC and H-Bridge |
| CN112332688A (en) * | 2020-05-28 | 2021-02-05 | 哈尔滨工程大学 | A composite controller for a three-level DC converter and its composite control method and energy control method |
| CN112054694A (en) * | 2020-09-16 | 2020-12-08 | 广东电网有限责任公司电力科学研究院 | Bidirectional converter optimization control method and device based on minimum current stress |
Non-Patent Citations (1)
| Title |
|---|
| K.NARASIMHA RAJU ET AL: "Hybrid Modulation Technique for Neutral Point Clamped Inverter to eliminate neutral point shift with minimum switching loss", 《TENCON 2015 - 2015 IEEE REGION 10 CONFERENCE》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118508760A (en) * | 2024-05-08 | 2024-08-16 | 合肥工业大学 | Heat balance method based on three-phase DC-DC converter |
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