CN114285292B - Five-level ANPC full-bridge isolation DC-DC converter and control method thereof - Google Patents
Five-level ANPC full-bridge isolation DC-DC converter and control method thereof Download PDFInfo
- Publication number
- CN114285292B CN114285292B CN202210010034.3A CN202210010034A CN114285292B CN 114285292 B CN114285292 B CN 114285292B CN 202210010034 A CN202210010034 A CN 202210010034A CN 114285292 B CN114285292 B CN 114285292B
- Authority
- CN
- China
- Prior art keywords
- state
- full
- anpc
- bridge
- switching
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
The invention discloses a five-level ANPC full-bridge isolation DC-DC converter and a control method thereof, belonging to the field of DC-DC converters, wherein the converter comprises: the main circuit comprises a transformer and active bridges at two sides of the transformer, and a 5L-ANPC full-bridge circuit is arranged in at least one active bridge; the 5L-ANPC full-bridge circuit is based on a five-level active neutral point clamping full-bridge circuit, and is provided with a bus positive electrode at a direct current side and a switching tube S connected with the bus positive electrode at the direct current side 1 Between which is connected in series a switching tube S 9 Negative electrode of direct-current bus and switching tube S connected with negative electrode of direct-current bus 4 Between which is connected in series a switching tube S 10 The zero states of O1, O2 and O3 are obtained; and the control driving unit is used for controlling the O3 state in the 5L-ANPC full-bridge circuit to be an intermediate state for switching between the O1 state and the O2 state, and realizing the switching between the zero state and the non-zero state through the O1 state and the O2 state. The dead zone effect existing in dead zone time of two adjacent half periods when the converter works can be eliminated, and the high-voltage switching tube can realize full-soft switching.
Description
Technical Field
The invention belongs to the field of direct current-direct current converters, and particularly relates to a five-level ANPC full-bridge isolation DC-DC converter and a control method thereof.
Background
A dual active bridge (Double Active Bridge, DAB) isolated DC-DC converter is one of the preferred circuits for constructing DC transformers. The bridge arm structure of the traditional DAB isolation DC-DC converter is usually an H-bridge circuit, and the voltage stress born by each switch tube is the DC bus voltage. The bidirectional DC-DC converter with the structure is difficult to realize application under high-pressure conditions under the limitation of the voltage-resistant level of a switching tube. In addition, the high-voltage-resistant switching tube has the problems of high switching loss and low switching frequency, and the improvement of the performance and the efficiency of the converter is limited.
In high voltage high power applications, DAB converters employ multi-level topologies. The five-level active neutral point clamped (5Level Active Neutral Point Clamped,5L-ANPC) full bridge topology is capable of reducing voltage stress and has excellent performance in medium-voltage high-power applications. The 5L-ANPC full-bridge topology is introduced into the DAB converter, so that more control degrees of freedom can be provided, the control flexibility is enhanced, and the DAB performance is improved. The 5L-ANPC DAB converter needs to perform balance control of the midpoint potential. Because of the parameter dispersion of the switch device and the direct current side capacitor and the influence of external disturbance, the midpoint voltage of the direct current bus of the converter is easy to diverge, and if no measures are taken, the circuit cannot work normally, and even the circuit is damaged. In addition, if the DAB converter (5L-ANPC DAB) is constructed directly using the 5L-ANPC full-bridge topology, there is a dead zone effect in the dead zone time at two adjacent half-cycles, resulting in a jump from zero level to non-zero level in the ac output voltage of the 5L-ANPC full-bridge, and an increase in system electromagnetic interference (Electromagnetic Interference, EMI). Therefore, it is necessary to introduce a new topology to acquire more switching states to eliminate such dead zone effects and to ensure that the midpoint potential of the circuit stabilizes at half the dc bus voltage.
Disclosure of Invention
Aiming at the defects and improvement demands of the prior art, the invention provides a five-level ANPC full-bridge isolation DC-DC converter and a control method thereof, and aims to solve the technical problem that dead zone time exists in dead zone time at two adjacent half periods when the DAB converter constructed by the existing 5L-ANPC full-bridge topological structure works.
In order to achieve the above object, according to one aspect of the present invention, there is provided a five-level ANPC full-bridge isolated DC-DC converter, including a main circuit and a control driving unit, the main circuit including a transformer and two active bridges respectively connected to both sides of the transformer, at least one of the active bridges being provided with a 5L-ANPC full-bridge circuit; in the 5L-ANPC full-bridge circuit, a switching tube S which is sequentially connected in series in the forward direction is arranged between the positive electrode and the negative electrode of a direct current side bus 9 、S 1 、S 2 、S 3 、S 4 And S is 10 A switching tube S which is sequentially connected in forward direction in series is arranged between the E1 and the E2 5 And S is 6 A switching tube S which is sequentially connected in forward series is arranged between F1 and F2 7 And S is 8 E1 is S 1 And S is 2 E2 is S 3 And S is 4 F1 is S 9 And S is 1 F2 is S 4 And S is 10 Has three zero states of O1 state, O2 state and O3 state; s in O1 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,0,1,0,1,1,1; s in O2 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,1,0,1,0,1,1; s in O3 state 1 -S 10 The switch states of (a) are as follows: 1,0,0,1,1,1,1,1,0,0; wherein 0 represents an off state, and 1 represents an on state; the control driving unit is used for controlling the on-off of each switching tube, so that the O3 state in the 5L-ANPC full-bridge circuit is an intermediate state switched between the O1 state and the O2 state, and the switching between the zero state and the non-zero state is realized through the O1 state and the O2 state.
Still further, in the 5L-ANPC full bridge circuit, the non-zero states include a P1 state, a P2 state, a P3 state, a PP state, an N1 state, an N2 state, an N3 state, and an NN state; switch tube S in P1 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,0,1,0,1,1,1; switch tube S in P2 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,1,0,0,1,1,1; switch tube S in P3 state 1 -S 10 The switch states of (a) are as follows: 0,1,1,0,1,1,0,1,1,1; switch tube S in PP state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,1,0,0,1,1,1; switch tube S in N1 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,1,0,1,0,1,1; switch tube S in N2 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,0,1,1,0,1,1; switch tube S in N3 state 1 -S 10 The switch states of (a) are as follows: 0,1,1,0,1,1,1,0,1,1; switch tube S in NN state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,0,1,1,0,1,1.
Further, the control driving unit is configured to control and drive the switching process of the switching state of the 5L-ANPC full-bridge circuit in one period to: o3- & gtO 1- & gtP 2- & gtP 3- & gtP 1- & gtPP- & gtP 1- & gtP 3- & gtP 2- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtN 1- & gtNN- & gtN 1- & gtN 3- & gtN 2- & gtO 3.
Further, in the 5L-ANPC full-bridge circuit, a switching tube S 5 And S is 6 The SiC tube and the rest of the switch tubes are Si tubes.
Further, the control driving unit is configured to control and drive the switching process of the switching state of the 5L-ANPC full-bridge circuit in one period to: o3- & gtO 1- & gtP 3- & gtPP- & gtP 3- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtNN- & gtN 3- & gtO 2- & gtO 3.
Furthermore, in the 5L-ANPC full-bridge circuit, a voltage-dividing capacitor C which is sequentially connected in series is also arranged between the positive electrode and the negative electrode of the direct-current side bus 1 And C 2 ，C 1 And C 2 Is connected with S 2 And S is 3 Is connected and serves as a neutral point O-point.
Further, the two sides of the main circuit are respectively connected with a direct current power supply and a load, and the direct current power supply is a three-port direct current power supply or a two-port direct current power supply; when the direct current power supply is a three-port direct current power supply, the connection point of the two voltage dividing capacitors in the 5L-ANPC full-bridge circuit is connected with the midpoint of the three-port direct current power supply.
Still further, the control driving unit includes a midpoint potential balance control unit and a driving waveform generator, and the midpoint potential balance control unit drives and controls the active bridge through the driving waveform generator.
According to another aspect of the present invention, there is provided a control method of the five-level ANPC full-bridge isolated DC-DC converter as described above, employing a control strategy of controlling a driving unit as described above to control driving the five-level ANPC full-bridge isolated DC-DC converter.
In general, through the above technical solutions conceived by the present invention, the following beneficial effects can be obtained:
(1) Compared with a 5L-ANPC full-bridge circuit applied in a traditional converter, the switching tube S is connected in series 9 、S 10 The circuit after the positive electrode and the negative electrode of the direct current side bus are respectively introduced, the formed topological redundant zero state is expanded from two of O1 and O2 to three of O1, O2 and O3, the output of a bridge arm is kept at zero level in the process of switching between the O1 and O2 and O3, no level jump phenomenon occurs, and the state of O3 is controlled to be an intermediate state of switching between the O1 state and the O2 state, so that on one hand, dead zone effect is effectively eliminated, and system electricity is reducedThe magnetic interference improves the reliability of the system, on the other hand, as the current in the O3 state has two parallel flow paths, the loss of the switching tube is reduced to a certain extent, and the O3 state is taken as the main zero state, the system loss can be reduced, and the efficiency is improved; in addition, the control strategy can ensure that all high-voltage switching tubes in the 5L-ANPC full-bridge circuit realize full-soft switching, so that the converter can be suitable for application occasions with high voltage level and high switching frequency, and ensures that the midpoint potential is stabilized near a given value and the converter is ensured to run stably and reliably;
(2) Aiming at the formed topology, an optimal modulation strategy of O3- & gtO 1- & gtP 2- & gtP 3- & gtP 1- & gtPP- & gtP 1- & gtP 3- & gtP 2- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtN 1- & gtNN- & gtN 1- & gtN 3- & gtN 2- & gtO 3 is provided to concentrate all hard switches in the 5L-ANPC full-bridge circuit on S 5 And S is 6 On, S is 5 And S is 6 The converter is provided with the SiC tube, so that the on-state loss and the switching loss can be reduced to the greatest extent by using the minimum SiC tube, and the maximum improvement of the converter efficiency can be realized at the lowest cost.
Drawings
FIG. 1 is a block diagram of a five-level ANPC full-bridge isolated DC-DC converter provided by an embodiment of the present invention;
FIG. 2 is a circuit diagram of a 5L-ANPC full-bridge topology applied in an inverter;
FIG. 3 is a circuit diagram of a 5L-ANPC full-bridge topology provided by an embodiment of the present invention;
FIG. 4 is a circuit diagram of an isolated bi-directional DC/DC converter based on a 5L-ANPC full-bridge circuit provided by an embodiment of the present invention;
fig. 5A to 5C are equivalent circuit diagrams of the 5L-ANPC full-bridge topology provided by the embodiment of the present invention in the O1 state, the O2 state, and the O3 state in sequence;
fig. 6A to fig. 6H are equivalent circuit diagrams of the 5L-ANPC full-bridge topology provided by the embodiments of the present invention in PP state, P1 state, P2 state, P3 state, NN state, N1 state, N2 state, N3 state;
fig. 7 is a waveform diagram of a modulation strategy in a control driving unit according to an embodiment of the present invention;
FIG. 8 is a waveform of a simulation of steady-state voltage and current of a five-level ANPC full-bridge isolated DC-DC converter according to an embodiment of the present invention;
fig. 9 is a simulation waveform of a steady-state midpoint potential of the five-level ANPC full-bridge isolated DC-DC converter according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
In the present invention, the terms "first," "second," and the like in the description and in the drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.
Fig. 1 is a block diagram of a five-level ANPC full-bridge isolated DC-DC converter according to an embodiment of the present invention. Referring to fig. 1, in conjunction with fig. 2 to 9, a detailed description will be given of the five-level ANPC full-bridge isolated DC-DC converter in this embodiment.
Referring to fig. 1, the five-level ANPC full-bridge isolated DC-DC converter includes a main circuit and a control drive unit. The main circuit comprises a transformer and active bridges respectively connected to two sides of the transformer, and a 5L-ANPC full-bridge circuit is arranged in at least one active bridge.
In the full-bridge circuit of 3,5L-ANPC, a switching tube S which is sequentially connected in series in the forward direction is arranged between the positive electrode and the negative electrode of a DC side bus 9 、S 1 、S 2 、S 3 、S 4 And S is 10 A switching tube S which is sequentially connected in forward direction in series is arranged between the E1 and the E2 5 And S is 6 A switching tube S which is sequentially connected in forward series is arranged between F1 and F2 7 And S is 8 E1 is S 1 And S is 2 E2 is S 3 And S is 4 F1 is S 9 And S is 1 F2 is S 4 And S is 10 Is connected to the connecting point of (c).
See5A-5C, the 5L-ANPC full-bridge circuit has three zero states, an O1 state, an O2 state, and an O3 state. S in O1 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,0,1,0,1,1,1, as shown in fig. 5A. S in O2 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,1,0,1,0,1,1, as shown in fig. 5B. S in O3 state 1 -S 10 The switch states of (a) are as follows: 1,0,0,1,1,1,1,1,0,0, as shown in fig. 5C. Wherein 0 represents an off state and 1 represents an on state.
The control driving unit is used for controlling the on-off of each switching tube, so that the O3 state in the 5L-ANPC full-bridge circuit is an intermediate state for switching between the O1 state and the O2 state, and the switching between the zero state and the non-zero state is realized through the O1 state and the O2 state.
FIG. 2 is a topology of a five-level active neutral point clamped full bridge circuit commonly used in converters, which, unlike the 5L-ANPC full bridge circuit of the present embodiment, does not include a switching tube S 9 And S is 10 Its switch tube S 1 、S 4 Is directly connected with the positive electrode and the negative electrode of the direct current side bus respectively. For the topology shown in fig. 2, to ensure that the circuit is functioning properly, the following rules should be followed: s is S 1 And S is equal to 2 、S 5 Complementary conduction, S 4 And S is equal to 3 、S 6 Complementary conduction, S 7 And S is equal to 8 Complementary turn-on, the topology has two redundant zero states.
In comparison with the topology shown in FIG. 2, in the embodiment of the present invention, the switching tubes S are connected in series 9 、S 10 After the circuit is introduced, the switch tube S is controlled 9 、S 10 Disconnection can realize S 1 And S is equal to 2 、S 5 Simultaneously turn on S 4 And S is equal to 3 、S 6 Simultaneously turn on and S 7 And S is equal to 8 And meanwhile, the circuit is opened without influencing the normal operation of the circuit, so that the redundant zero state of the topology is expanded to three types (marked as O1, O2 and O3) as shown in the figures 5A-5C respectively. O1, O2 and the switch state of the output non-zero level are switched, O3 is the intermediate state of the state switching of O1 and O2, and in the switching process of O1, O2 and O3, the output of a bridge arm is kept at zero level, and no level jump phenomenon occurs. By such zero shapeThe state switching mode effectively eliminates dead zone effect and reduces electromagnetic interference of the system on one hand; on the other hand, the current in the O3 state has two parallel flow paths, so that the loss of the switching tube is reduced to a certain extent, and the O3 state is taken as a main zero state, so that the system loss can be reduced, and the efficiency is improved.
According to an embodiment of the present invention, the control driving unit includes a midpoint potential balance control unit and a driving waveform generator. The neutral potential balance control unit drives and controls the active bridge through the driving waveform generator.
Specifically, referring to fig. 1, in the five-level ANPC full-bridge isolated DC-DC converter, a main circuit is sequentially configured with an auxiliary inductor L, a primary active bridge, and a primary DC power supply or load on a primary side of a transformer T, and a secondary active bridge and a secondary DC power supply or load on a secondary side of the transformer. At least one side of the primary side active bridge and the secondary side active bridge circuits comprises a 5L-ANPC full bridge circuit.
Referring to fig. 3,5L-ANPC full-bridge circuit includes ten switching tubes S 1 、S 2 、S 3 、S 4 、S 5 、S 6 、S 7 、S 8 、S 9 And S is 10 Two direct-current side voltage dividing capacitors C 1 And C 2 。S 5 And S is 6 The connection midpoint A of the capacitor is the bridge arm alternating current output end and is connected with the auxiliary inductor L. S is S 7 And S is 8 The connection midpoint B of the transformer is a bridge arm alternating current input end and is connected with the transformer T. Voltage dividing capacitor C 1 And C 2 The series connection is arranged between the positive electrode and the negative electrode of the direct current side bus, namely, two ends are respectively connected with the high-voltage end and the low-voltage end of a power supply or a load, and the series connection midpoints O and S 2 And S is 3 Is connected at the mid-point of the series.
Referring to FIG. 4, taking a primary side active bridge and a secondary side active bridge as an example, the primary side 5L-ANPC full bridge circuit is denoted as B1, and the secondary side 5L-ANPC full bridge circuit is denoted as B2. The direct current side of the primary side 5L-ANPC full-bridge circuit is connected with a primary side power supply or load; the direct current side of the secondary side 5L-ANPC full-bridge circuit is connected with a secondary side power supply or load; the auxiliary inductor L is connected with the alternating current side of the primary side 5L-ANPC full-bridge circuit; the auxiliary inductor L is connected with the primary side of the transformer.
When energy flows from the primary side to the secondary side, the primary side 5L-ANPC full-bridge circuit is in an inversion state, and the secondary side 5L-ANPC full-bridge circuit is in a rectification state; when energy flows from the secondary side to the primary side, the primary side 5L-ANPC full-bridge circuit is in a rectifying state, and the secondary side 5L-ANPC full-bridge circuit is in an inverting state.
The two sides of the main circuit are respectively connected with a direct current power supply and a load, and at least one direct current power supply of a primary side direct current power supply or a load and a secondary side direct current power supply or a load is used as an energy source of the system. The direct current power supply is a three-port direct current power supply or a two-port direct current power supply. When the direct current power supply is a three-port direct current power supply, the connection point of the two voltage dividing capacitors in the 5L-ANPC full-bridge circuit is connected with the midpoint of the three-port direct current power supply.
Referring to the single 5L-ANPC full-bridge circuit topology shown in FIG. 3, V dc 、V dc1 、V dc2 、V AB And I represents a dc side voltage, a dc side upper bus capacitor voltage, a dc side lower bus capacitor voltage, an ac side voltage, and an ac side current thereof, respectively. As shown in fig. 3, for the B1 side, V dc ＝V 1 ,V dc1 ＝V 11 ,V dc2 ＝V 12 ,V AB ＝V p ,I＝i L The method comprises the steps of carrying out a first treatment on the surface of the For the B2 side, V dc ＝V 2 ,V dc1 ＝V 21 ,V dc2 ＝V 22 ,V AB ＝V s ,I＝-ni L . Wherein n is 1 is the transformation ratio of the transformer.
In the 5L-ANPC full-bridge circuit, the non-zero state comprises a P1 state, a P2 state, a P3 state, a PP state, an N1 state, an N2 state, an N3 state and an NN state, and the switching tube S is arranged in each state 1 -S 10 The switching states of (2) are shown in table 1.
TABLE 1
Wherein '0' and '1' respectively represent the switch of the switching tubeBreaking and conducting; v (V) PP 、V P 、V O 、V N And V NN Respectively represent V dc 、V dc /2、0、-V dc 2 and-V dc Is a voltage level of the output voltage of (a); PP and NN respectively represent output V PP 、V NN A corresponding switch state; p1, P2, P3 represent the output V P Three redundant switch states of (2); n1, N2, N3 represent the output V N Three redundant switch states of (2); o1, O2, O3 represent the output V O Is provided for the three redundant switch states. Will output V O The switching state of a level is referred to as zero state, and the switching state of the other level output is referred to as non-zero state. In the 5L-ANPC full-bridge circuit, the PP state is shown in FIG. 6A, the P1 state is shown in FIG. 6B, the P2 state is shown in FIG. 6C, the P3 state is shown in FIG. 6D, the NN state is shown in FIG. 6E, the N1 state is shown in FIG. 6F, the N2 state is shown in FIG. 6G, and the N3 state is shown in FIG. 6H.
In an embodiment of the present invention, the control driving unit is configured to control and drive a switching process of a switching state of the 5L-ANPC full-bridge circuit in one period to: o3- & gtO 1- & gtP 2- & gtP 3- & gtP 1- & gtPP- & gtP 1- & gtP 3- & gtP 2- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtN 1- & gtNN- & gtN 1- & gtN 3- & gtN 2- & gtO 3. Under the modulation strategy, the modulation waveform of each switch tube is shown in FIG. 7, wherein G 1 -G 10 Representing a switching tube S 1 -S 10 T is set as the driving signal of (1) s Representing an output period, T hs Representing half of the output period.
All switching processes between different switch states of the same output voltage level, including O1-O3-O2, P1-P3-P2, N1-N3-N2, can be considered as switching processes between a single current path state and a dual current path state. Taking O1-O3-O2 switching as an example, when the zero state is switched from O1 to O3, the switching tube S is turned off first 2 、S 9 And S is 10 Then turn on S 1 、S 5 、S 7 . During the handover process, S 2 、S 9 And S is 10 Is zero current off (zero current switching turn-off, ZCS-off). And at S 1 、S 5 、S 7 If the influence of parasitic capacitance of the switching tube is considered in the switching-on process, the switching-on speed of the low-voltage tube is higherFast S 1 、S 5 Will precede the high-pressure tube S 7 Turn on, thus S 7 Is approximately zero voltage on (zero voltage switching turn-on, ZVS-on); in high power applications, the parasitic capacitance of the switch tube is generally negligible, S 1 、S 5 、S 7 Are ZVS-on. When the switching state O3 is switched to O2, the switching tube S is turned off first 4 、S 6 And S is 8 Then turn on the switching tube S 3 、S 9 And S is 10 。S 4 、S 6 And S is 8 During shutdown, the tube drop remains at 0, thus turning off at zero voltage (zero voltage switching turn-off, ZVS-off). If neglecting the influence of parasitic capacitance of the switching tube, the switching tube S 3 、S 9 And S is 10 The current remains zero during the turn-on process, thus turning on for zero current (zero current switching turn-on, ZCS-on). The switching process of P1-P3-P2 and N1-N3-N2 can be analyzed in a similar way, so that the switching process between the single current path state and the double current path state can realize the soft switching action of the switching tube without generating switching loss.
For switching process between switching states of different output voltage levels, including O1-P2, P1-PP, O2-N2, N1-NN, only in switching tube S 5 And S is 6 There is a hard switching loss on the upper. Therefore, under this modulation strategy, the switching tube S is switched on 5 And S is 6 The switching tube is arranged as a SiC tube, and the rest of the switching tubes are arranged as Si tubes. On the one hand, when the zero level and the non-zero level are output, the current flows through the switch tube S 5 And S is 6 Thus S 5 And S is 6 The on-state loss generated on the silicon carbide is more remarkable than that of other low-voltage switching tubes, and the SiC device generally has better on-state performance than that of the Si device and is used for S 5 And S is 6 The on-state loss can be reduced to the greatest extent; on the other hand, based on the modulation strategy, switching losses are concentrated in S during all switching processes 5 And S is 6 In this way, the hard switching operation is concentrated on the SiC device, and switching loss can be greatly reduced.
In another embodiment of the present invention, the control driving unit is used for controlling and driving the 5L-ANPC full-bridge circuitThe switching process of the switch state in one period is as follows: o3- & gtO 1- & gtP 3- & gtPP- & gtP 3- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtNN- & gtN 3- & gtO 2- & gtO 3. Under the modulation strategy, five levels can be output when the converter operates normally, and meanwhile, the operation performance of the converter is improved. In the respective switching states given in table 1, I always has two current paths in the P3, N3 and O3 switching states, with lower on-state losses, regardless of the direction of the output current I. Therefore, in the present modulation strategy, the P3 switch state is selected as the output V P The main switching state of the level is N3 switching state as output V N The main switching state of the level is selected from the O3 switching state as the output V O The main switching state of the level.
Under the two modulation strategies, the high-voltage switch tube S 7 、S 8 、S 9 And S is 10 All are soft switching operations, so DAB converters can still achieve higher switching frequencies even in high voltage class applications.
Taking the experimental parameters shown in table 2 as an example, the five-level ANPC full-bridge isolation DC-DC converter based on the 5L-ANPC full-bridge circuit is taken to describe the performance of the converter in this embodiment. When the provided converter works in a steady state, the experimental result is shown in fig. 8, and it can be seen that the five-level voltage waveform without level jump can effectively reduce electromagnetic interference. By applying the modulation strategy in this embodiment, the midpoint potential waveforms of the B1 and B2 sides are shown in fig. 9, and it can be seen that the midpoint potential on both sides is stably controlled to be about 200V and 160V, the stabilizing effect is good, the midpoint potential ripple on the primary side is lower than 1V, and the midpoint potential ripple on the secondary side is lower than 7V.
TABLE 2
In summary, the five-level ANPC full-bridge isolation DC-DC converter provided in the embodiment can eliminate level jump caused by dead zone effect, effectively reduce voltage change rate dv/dt, thereby reducing EMI and improving reliability of the system; all high-voltage switching tubes in the 5L-ANPC full-bridge DAB converter can realize full soft switching, and the converter can be suitable for application occasions with high voltage class and high switching frequency. The modulation strategy adopted in the embodiment adopts the switching state of the double-current branch to reduce on-state loss, realizes the soft switching action of eight switching tubes through the switching of the single-current branch state and the double-current branch state, and concentrates the switching loss on two inner tubes of a bridge arm; furthermore, the two inner pipes are realized by the SiC switching tube, so that on-state loss and switching loss can be greatly reduced, and the efficiency of the converter is improved; in addition, the control driving unit adopts a neutral point potential balance control method based on duty ratio change and hysteresis control, so that the neutral point potential can be ensured to be stabilized near a given value, and the DAB converter can be ensured to run stably and reliably.
The embodiment of the invention also provides a control method of the five-level ANPC full-bridge isolation DC-DC converter. The method adopts a control strategy for controlling a driving unit in the five-level ANPC full-bridge isolation DC-DC converter shown in the figures 1-9 to control and drive the five-level ANPC full-bridge isolation DC-DC converter. For details, please refer to the five-level ANPC full-bridge isolated DC-DC converter shown in fig. 1-9, which is not described herein.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (9)
1. The five-level ANPC full-bridge isolation DC-DC converter is characterized by comprising a main circuit and a control driving unit, wherein the main circuit comprises a transformer and two active bridges respectively connected to two sides of the transformer, and a 5L-ANPC full-bridge circuit is arranged in at least one active bridge;
in the 5L-ANPC full-bridge circuit, a switching tube S which is sequentially connected in series in the forward direction is arranged between the positive electrode and the negative electrode of a direct current side bus 9 、S 1 、S 2 、S 3 、S 4 And S is 10 ，E1、E2 are sequentially connected in series with a switching tube S in forward direction 5 And S is 6 ，F1、F2 are sequentially connected in series with a switching tube S in forward direction 7 And S is 8 ，E1 is S 1 And S is 2 Is connected with the connecting point of the (c),E2 is S 3 And S is 4 Is connected with the connecting point of the (c),F1 is S 9 And S is 1 Is connected with the connecting point of the (c),F2 is S 4 And S is 10 Has three zero states of O1 state, O2 state and O3 state; s in O1 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,0,1,0,1,1,1; s in O2 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,1,0,1,0,1,1; s in O3 state 1 -S 10 The switch states of (a) are as follows: 1,0,0,1,1,1,1,1,0,0; wherein 0 represents an off state, and 1 represents an on state;
the control driving unit is used for controlling the on-off of each switching tube, so that the O3 state in the 5L-ANPC full-bridge circuit is an intermediate state switched between the O1 state and the O2 state, and the switching between the zero state and the non-zero state is realized through the O1 state and the O2 state.
2. The five-level ANPC full-bridge isolated DC-DC converter of claim 1, wherein the non-zero states in the 5L-ANPC full-bridge circuit include a P1 state, a P2 state, a P3 state, a PP state, an N1 state, an N2 state, an N3 state, and an NN state;
switch tube S in P1 state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,0,1,0,1,1,1;
switch tube S in P2 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,1,0,0,1,1,1;
switch tube S in P3 state 1 -S 10 The switch states of (a) are as follows: 0,1,1,0,1,1,0,1,1,1;
switch tube S in PP state 1 -S 10 The switch states of (a) are as follows: 1,0,1,0,1,0,0,1,1,1;
switch tube S in N1 state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,1,0,1,0,1,1;
switch tube S in N2 state 1 -S 10 In turn of the switch state of (a)The method comprises the following steps: 1,0,1,0,0,1,1,0,1,1;
switch tube S in N3 state 1 -S 10 The switch states of (a) are as follows: 0,1,1,0,1,1,1,0,1,1;
switch tube S in NN state 1 -S 10 The switch states of (a) are as follows: 0,1,0,1,0,1,1,0,1,1.
3. The five-level ANPC full-bridge isolated DC-DC converter of claim 2, wherein the control driving unit is configured to control a switching process of driving the switching state of the 5L-ANPC full-bridge circuit in one cycle to: o3- & gtO 1- & gtP 2- & gtP 3- & gtP 1- & gtPP- & gtP 1- & gtP 3- & gtP 2- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtN 1- & gtNN- & gtN 1- & gtN 3- & gtN 2- & gtO 3.
4. The five-level ANPC full-bridge isolated DC-DC converter of claim 3, wherein in the 5L-ANPC full-bridge circuit, switching tube S 5 And S is 6 The SiC tube and the rest of the switch tubes are Si tubes.
5. The five-level ANPC full-bridge isolated DC-DC converter of claim 2, wherein the control driving unit is configured to control a switching process of driving the switching state of the 5L-ANPC full-bridge circuit in one cycle to: o3- & gtO 1- & gtP 3- & gtPP- & gtP 3- & gtO 1- & gtO 3- & gtO 2- & gtN 3- & gtNN- & gtN 3- & gtO 2- & gtO 3.
6. The five-level ANPC full-bridge isolation DC-DC converter as set forth in claim 1, wherein a voltage-dividing capacitor is further arranged between the positive and negative poles of the DC bus in the 5L-ANPC full-bridge circuit in seriesC 1 AndC 2 ，C 1 andC 2 is connected with S 2 And S is 3 Is connected and serves as a neutral point O-point.
7. The five-level ANPC full-bridge isolated DC-DC converter of any one of claims 1-6, wherein the two sides of the main circuit are connected to a DC power supply and a load, respectively, the DC power supply being a three-port DC power supply or a two-port DC power supply;
when the direct current power supply is a three-port direct current power supply, the connection point of the two voltage dividing capacitors in the 5L-ANPC full-bridge circuit is connected with the midpoint of the three-port direct current power supply.
8. The five-level ANPC full-bridge isolated DC-DC converter of any one of claims 1-6, wherein the control drive unit includes a midpoint potential balance control unit and a drive waveform generator, the midpoint potential balance control unit driving controlling the active bridge by the drive waveform generator.
9. A control method of a five-level ANPC full-bridge isolated DC-DC converter as claimed in any one of claims 1-8, characterized in that the control strategy of the control driving unit is adopted to control driving the five-level ANPC full-bridge isolated DC-DC converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210010034.3A CN114285292B (en) | 2022-01-06 | 2022-01-06 | Five-level ANPC full-bridge isolation DC-DC converter and control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210010034.3A CN114285292B (en) | 2022-01-06 | 2022-01-06 | Five-level ANPC full-bridge isolation DC-DC converter and control method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114285292A CN114285292A (en) | 2022-04-05 |
| CN114285292B true CN114285292B (en) | 2023-10-20 |
Family
ID=80880527
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210010034.3A Active CN114285292B (en) | 2022-01-06 | 2022-01-06 | Five-level ANPC full-bridge isolation DC-DC converter and control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114285292B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109756138A (en) * | 2019-01-29 | 2019-05-14 | 河海大学 | A kind of control circuit of five Level Full Bridges inverter |
| CN110299861A (en) * | 2019-08-02 | 2019-10-01 | 江苏固德威电源科技股份有限公司 | Boost active neutral-point-clamped type five-level converter |
| CN113078820A (en) * | 2021-03-05 | 2021-07-06 | 华中科技大学 | Nine-switch tube five-level active neutral point clamped dual-active bridge isolation DC-DC converter |
-
2022
- 2022-01-06 CN CN202210010034.3A patent/CN114285292B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109756138A (en) * | 2019-01-29 | 2019-05-14 | 河海大学 | A kind of control circuit of five Level Full Bridges inverter |
| CN110299861A (en) * | 2019-08-02 | 2019-10-01 | 江苏固德威电源科技股份有限公司 | Boost active neutral-point-clamped type five-level converter |
| CN113078820A (en) * | 2021-03-05 | 2021-07-06 | 华中科技大学 | Nine-switch tube five-level active neutral point clamped dual-active bridge isolation DC-DC converter |
Non-Patent Citations (2)
| Title |
|---|
| A DAB Converter Constructed by Nine-Switch Five-Level Active-Neutral-Point-Clamped Bridges;Na Gao等;《2021 IEEE Energy Conversion Congress and Exposition (ECCE)》;第2563-2569页 * |
| 基于IGBT 行为模型的有源中点钳位 五电平变换器损耗特性分析;叶伟伟等;《电工技术学报》;第第36卷卷;第218-230页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114285292A (en) | 2022-04-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8780585B2 (en) | Double phase-shifting full-bridge DC-to-DC converter | |
| CN101479917B (en) | A zero voltage zero current switching converter | |
| CN1210390A (en) | Sub-resonant series resonant converter having improved form factor and reduced EMI | |
| KR20130043612A (en) | Dc-dc converter circuit for high input-to-output voltage conversion | |
| US20120187879A1 (en) | Zero-voltage-transition soft switching converter | |
| CN110798072B (en) | Modulation method and system of ANPC active bridge applied to DAB structure | |
| CN109104098B (en) | Converter and driving method thereof | |
| US10432101B2 (en) | Power conversion apparatus | |
| CN110768534B (en) | Isolated double-half-bridge ANPC active bridge three-level DC/DC converter | |
| US11437915B2 (en) | Converter | |
| JP2019118234A (en) | Isolated bidirectional dc/dc converter and control method of the same | |
| CN111490577A (en) | Double-end output charging circuit and auxiliary circuit switch control method thereof | |
| CN111092553A (en) | Bidirectional DC/DC converter based on isolated full-bridge ANPC and H bridge | |
| TWI479795B (en) | Near zero current-ripple inversion or rectification circuits | |
| CN110707939B (en) | DC-DC converter based on three levels of isolated half-bridge ANPC and H bridge | |
| CN113078820B (en) | Nine-switch tube five-level active neutral point clamped dual-active bridge isolation DC-DC converter | |
| KR20200024491A (en) | New Phase-Shifted Full-Bridge DC-DC Converter Using Center-Tapped Clamp Circuit | |
| CN115664223B (en) | quasi-Z-source full-bridge converter and control method | |
| CN114285292B (en) | Five-level ANPC full-bridge isolation DC-DC converter and control method thereof | |
| KR20050083812A (en) | Zero-voltage-switching single-switched resonant dc link with minimized conduction loss | |
| CN111384858A (en) | Full-bridge circuit and full-bridge converter | |
| CN109194144A (en) | A kind of double positive activation type booster circuits of crisscross parallel | |
| CN115149809A (en) | Non-isolated full-bridge cascaded converter circuit and control method thereof | |
| Choi et al. | A Novel Switching Algorithm to improve Efficiency at light load conditions for Three-Phase DAB Converter in LVDC Application | |
| WO2018157797A1 (en) | Full-bridge resonant converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |