CN110071651B - Non-isolated boost inverter circuit with symmetrical structure - Google Patents
Non-isolated boost inverter circuit with symmetrical structure Download PDFInfo
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- CN110071651B CN110071651B CN201910508590.1A CN201910508590A CN110071651B CN 110071651 B CN110071651 B CN 110071651B CN 201910508590 A CN201910508590 A CN 201910508590A CN 110071651 B CN110071651 B CN 110071651B
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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
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
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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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
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Abstract
The invention discloses a non-isolated boost inverter circuit with symmetrical structure, which relates to the technical field of power electronic inversion and is used for improving the boost capability of a non-isolated inverter. The non-isolated boost inverter circuit with symmetrical structure adopts variable duty ratio and changes a capacitor discharge path to realize boost inversion. The system comprises a boosting network, an energy transmission network and an inversion network. Wherein the boost network comprises: input DC power supply U in Inductance L1, switching tube S4. The energy transfer network includes: DC power supply U in Inductance L1, diode D2, capacitor C1, and capacitor C2. The inverter network consists of a capacitor C1, a capacitor C2, a switching tube S3, a switching tube S5, a switching tube S6 and a load. The non-isolated boost inverter circuit with symmetrical structure has the boost function, continuous input current, low circuit switching loss and high system reliability. The method is suitable for the occasions with low input voltage and large range variation.
Description
Technical Field
The invention relates to the technical field of power electronic inversion, in particular to a non-isolated boost inverter circuit with symmetrical structure.
Background
The continuous promotion of industrialization makes the demand of human beings for energy continuously increase, and the exhaustion of resources has become a serious crisis facing human beings. An inverter is an important power conversion device in the field of power electronics, and is widely applied in various industrial fields, and a traditional inverter can only perform buck-boost inversion, so in practical application, a boost inverter circuit is adopted to achieve the boost function.
At present, the non-isolated inverter circuit can realize boosting by two methods, the first method is realized by cascading a primary DC-DC chopper circuit on a DC side to raise the voltage level and then forming a two-stage circuit through an inverter, and the two-stage circuit structure has multiple conversion stages, so that the system is complex, the cost is high, and the number of devices is large and the operation is complex. Another method is to use single stage boost inversion, which makes the inverter circuit work in buck-boost mode by adding a passive impedance network between the input power side and the inverter bridge. The direct-connection duty ratio is introduced to complete boosting, the duty ratio is limited by the modulation factor of the inverter, boosting capacity is limited, and power loss of a switching tube is large, so that a circuit structure with strong boosting capacity, high operation efficiency, simple control and high reliability is selected to be a key point of research.
Disclosure of Invention
The purpose of the invention is that: the invention discloses a non-isolated boost inverter circuit with symmetrical structure, which adopts variable duty ratio and changes a capacitor discharge path to realize boost inversion. The topology structure is symmetrical, and has the characteristics of larger boosting capacity, fewer passive devices, continuous input current and high output voltage precision.
In order to achieve the purpose of the invention, the following technical scheme is adopted: input voltage U through boost network in Boosting is performed. The voltage at two ends of the capacitor in the energy transmission network cannot be suddenly changed after the circuit enters a steady state after the voltage boosting network is inserted, so that the voltage disturbance at the input side can be inhibited, the reliability of the circuit is improved, the waveform distortion of the output voltage is reduced, the voltage impact of the switching tube is reduced, and the stability of the circuit is increased.
The non-isolated boosting inversion circuit with symmetrical structure comprises a boosting network, an energy transmission network and an inversion network, wherein the boosting network comprises the following components: input DC power supply Uin, inductance L1, switching tube S4, the energy transmission network includes: the DC power supply Uin, the inductor L1, the diode D2, the capacitor C1 and the capacitor C2, and the inverter network consists of the capacitor C1, the capacitor C2, the switching tube S3, the switching tube S5, the switching tube S6 and a load.
The concrete connection mode is as follows: the positive electrode of the input direct current power supply Uin is connected with one end of an inductor L1, the negative electrode of the input direct current power supply Uin is connected with the source electrode of a switch tube S1 and the source electrode of a switch tube S4 respectively, the positive electrode of a capacitor C1 is connected with one end of a drain electrode of the switch tube S1 and one end of the inductor L1, the positive electrode of a capacitor C2 is connected with the drain electrode of the switch tube S4 and one end of the inductor L1, the negative electrode of the capacitor C1 is connected with the source electrode of a switch tube S2 and the anode of a diode D1 respectively, the negative electrode of the capacitor C2 is connected with the source electrode of the switch tube S5, the cathode of the diode D2 is connected with the source electrode of the switch tube S4 respectively, the drain electrode of the switch tube S2 is connected with the drain electrode of the switch tube S6, the source electrode of the switch tube S6 is connected with the drain electrode of the switch tube S5 respectively, the source electrode of the switch tube S3 is connected with the anode of the diode DS3 and the cathode respectively, and the source electrode of the switch tube S6 and the drain electrode of the switch tube S2 are connected with the two ends of the switch tube S5 respectively.
Compared with the traditional voltage source type boost inverter circuit, the non-isolated boost inverter circuit with symmetrical structure reduces the number of passive devices in the circuit, and has the advantages of simple modulation method, low switching loss and symmetrical topological structure. The direct current power supply and the input inductor L1 form a boosting network, the inductor plays a role in voltage boosting when discharging, the two intermediate capacitors are charged to store energy, energy is transferred to a load after the capacitors store energy, the voltage amplitude of the direct current bus can be increased, and the boosting inversion function is realized by adopting the switching-on time sequence change of four switching tubes in the energy transferring process.
Compared with the prior art, the invention has the following technical effects:
(1) The single-stage boosting inversion function is achieved, the circuit is not required to be connected into an isolation transformer for boosting, and the cascade chopper circuit at the front stage of inversion is not required, so that the circuit volume and cost are reduced, and the system integration level is improved.
(2) The boost inversion is realized by adopting a variable duty ratio and changing a capacitor discharge path, and the amplitude of the output voltage can be adjusted.
(3) The energy transmission network is inserted after the voltage boosting network, the voltage at two ends of the capacitor in the energy transmission network cannot be suddenly changed after the circuit enters a steady state, the voltage disturbance at the input side can be inhibited, and the reliability of the circuit is improved.
(4) The control method of the inverter circuit is simple, fewer switching tubes work in a high-frequency state, and switching loss is reduced.
Drawings
Fig. 1 is a schematic diagram of a non-isolated boost inverter circuit with symmetrical structure according to the present invention.
Fig. 2 is an equivalent circuit diagram of the symmetrical non-isolated boost inverter circuit of the present invention when the output current is forward.
Fig. 3 is an equivalent circuit diagram of the symmetrical non-isolated boost inverter circuit of the present invention when the output current is reversed.
Fig. 4 is a switching control sequence diagram of the non-isolated boost inverter circuit with symmetrical structure according to the invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings: as shown in fig. 1, fig. 1 is a schematic diagram of a non-isolated boost inverter circuit with symmetrical structure according to the present invention. The non-isolated boosting inversion circuit with symmetrical structure consists of a boosting network, an energy transmission network and an inversion network; wherein the boost network comprises: input DC power supply U in The inductance L1, the switching tube S1 and the switching tube S4, and the energy transmission network comprises: DC power supply U in The inverter network consists of a capacitor C1, a capacitor C2, a switching tube S3, a switching tube S5, a switching tube S6 and a load;
the concrete connection mode is as follows: input DC power supply U in The positive electrode is connected with one end of the inductor L1 and is input with a direct current power supply U in The negative electrode is respectively connected with the source electrode of the switch tube S1 and the source electrode of the switch tube S4, the positive electrode of the capacitor C1 is connected with one end of the switch tube S1 drain electrode and the inductor L1, the positive electrode of the capacitor C2 is connected with one end of the switch tube S4 drain electrode and the inductor L1, the negative electrode of the capacitor C1 is connected with the source electrode of the switch tube S2 and the anode of the diode D1, the negative electrode of the capacitor C2 is connected with the source electrode of the switch tube S5, the cathode of the diode D1 is connected with the source electrode of the switch tube S1, the cathode of the diode D2 is connected with the source electrode of the switch tube S4, the drain electrode of the switch tube S2 is connected with the drain electrode of the switch tube S3, the source electrode of the switch tube S3 is connected with the drain electrode of the switch tube S5, the source electrode of the drain electrode of the switch tube S3 is respectively connected with the anode of the diode DS3 and the cathode, the source electrode of the switch tube S6 is respectively connected with the anode of the diode DS6, and the drain electrode of the switch tube S2 is respectively connected with two ends of the switch tube S5.
According to the working direction of the output current, the output current forward mode and the output current reverse mode can be performed.
Fig. 2 is an equivalent circuit of the symmetrical non-isolated boost inverter circuit in the invention in the output current forward mode. As shown in fig. 2 (I), the switching transistors S3, S4, S5 are turned on, the switching transistors S1, S2, S6 are turned off, U in L1 and S4 form a closed loop, and a power supply U in Charging an input inductor L1, storing energy of the input inductor L1, and linearly rising current; the capacitor C2, the switching tubes S4, S3 and S5 and the load form a closed loop, D2 is cut off, and the capacitor C2 discharges to the load; then as shown in FIG. 2 (II), the switching tubes S1, S2, S4, S5, S6 are turned off, and the switching tube S3 is turned on, wherein U in L1, C2 and D2 form a closed loop, U in Charging the capacitor C2 with L1, the current of the input inductor L1 decreases linearly; DS6, S3 and the load form a closed loop, and the current flowing through the filter inductor also linearly decreases.
Fig. 3 is an equivalent circuit of the symmetrical non-isolated boost inverter circuit of the present invention in the output current forward mode. As shown in fig. 3 (I). The switching tubes S1, S2 and S6 are turned on, the switching tubes S3, S4 and S5 are turned off, U in L1 and S1 form a closed loop, and a power supply U in Charging an input inductor L1, storing energy of the input inductor L1, and linearly rising current; the capacitor C1, the switching tubes S1, S6 and S2 and the load form a closed loop, the D1 is cut off, and the capacitor C1 discharges to the load. Then as shown in FIG. 3 (II), the switching tubes S1, S2, S3, S4, S5 are turned off, and the switching tube S6 is turned on, wherein U in L1, C1 and D1 form a closed loop, U in Charging the capacitor C1 with L1, the current of the input inductor L1 decreases linearly; DS6, S6 and the load form a closed loop, and the current flowing through the filter inductor also linearly decreases.
Fig. 4 is a switching control sequence diagram of the non-isolated boost inverter circuit with symmetrical structure according to the invention. The opening states of S1 and S2 are consistent, the opening states of S4 and S5 are consistent in the upper half period, the opening states of S6 and S3 are consistent in the lower half period, and S6 and S3 only work in the power frequency period. The control method is simple, fewer switching tubes work in a high-frequency state, and switching loss is reduced.
Compared with the prior art, the invention has the following technical effects:
(1) The single-stage boosting inversion function is achieved, the circuit is not required to be connected into an isolation transformer for boosting, and the cascade chopper circuit at the front stage of inversion is not required, so that the circuit volume and cost are reduced, and the system integration level is improved.
(2) The boost inversion is realized by adopting a variable duty ratio and changing a capacitor discharge path, and the amplitude of the output voltage can be adjusted.
(3) The energy transmission network is inserted after the voltage boosting network, the voltage at two ends of the capacitor in the energy transmission network cannot be suddenly changed after the circuit enters a steady state, the voltage disturbance at the input side can be inhibited, and the reliability of the circuit is improved.
(4) The control method of the inverter circuit is simple, fewer switching tubes work in a high-frequency state, and switching loss is reduced.
Claims (6)
1. The non-isolated boost inverter circuit with symmetrical structure is characterized by comprising a boost network, an energy transmission network and an inverter network; wherein the boost network comprises: input DC power supply U in The inductance L1, the switching tube S1 and the switching tube S4, and the energy transmission network comprises: DC power supply U in The inverter network consists of a capacitor C1, a capacitor C2, a switching tube S3, a switching tube S5, a switching tube S6 and a load, and the circuit structure is symmetrical;
the concrete connection mode is as follows: input DC power supply U in The positive electrode is connected with one end of the inductor L1 and is input with a direct current power supply U in The negative electrode is respectively connected with the source electrode of the switch tube S1 and the source electrode of the switch tube S4, the positive electrode of the capacitor C1 is connected with one end of the drain electrode of the switch tube S1 and one end of the inductor L1, the positive electrode of the capacitor C2 is connected with one end of the drain electrode of the switch tube S4 and one end of the inductor L1, the negative electrode of the capacitor C1 is connected with the source electrode of the switch tube S2 and the anode of the diode D1, the negative electrode of the capacitor C2 is connected with the source electrode of the switch tube S5 and the anode of the diode D2, the cathode of the diode D1 is connected with the source electrode of the switch tube S1, and the cathode of the diode D2 is connected with the switch tube S4, the drain electrode of the switch tube S2 is connected with the source electrode of the switch tube S3, the drain electrode of the switch tube S3 is connected with the drain electrode of the switch tube S6, the source electrode of the switch tube S6 is connected with the drain electrode of the switch tube S5, the source electrode and the drain electrode of the switch tube S3 are respectively connected with the anode and the cathode of the diode DS3, the source electrode and the drain electrode of the switch tube S6 are respectively connected with the anode and the cathode of the diode DS6, and the drain electrode of the switch tube S2 and the drain electrode of the switch tube S5 are respectively connected with two ends of a load.
2. The non-isolated boost inverter circuit of claim 1, wherein the inverter circuit employs a variable duty cycle and a varying capacitive discharge path to achieve boost inversion.
3. The non-isolated boost inverter circuit of claim 1, wherein when the circuit is operated with an output current greater than zero, the switching transistors S3, S4, S5 are turned on, the switching transistors S1, S2, S6 are turned off, U in L1 and S4 form a closed loop, and a power supply U in Charging an input inductor L1, storing energy of the input inductor L1, and linearly rising current; the capacitor C2, the switching tubes S4, S3 and S5 and the load form a closed loop, D2 is cut off, and the capacitor C2 discharges to the load; then the switching tubes S1, S2, S4, S5, S6 are turned off, and the switching tube S3 is turned on, wherein U in L1, C2 and D2 form a closed loop, U in Charging the capacitor C2 with L1, the current of the input inductor L1 decreases linearly; DS6, S3 and the load form a closed loop, and the current flowing through the filter inductor also linearly decreases.
4. The non-isolated boost inverter circuit of claim 1, wherein when the circuit is operated with an output current less than zero, the switching transistors S1, S2, S6 are turned on, the switching transistors S3, S4, S5 are turned off, U in L1 and S1 form a closed loop, and a power supply U in Charging an input inductor L1, storing energy of the input inductor L1, and linearly rising current; the capacitor C1, the switching tubes S1, S6 and S2 and the load form a closed loop, the D1 is cut off, and the capacitor C1 discharges to the load; then the switching tubes S1, S2, S3, S4, S5 are turned off,switch tube S6 is turned on, wherein U in L1, C1 and D1 form a closed loop, U in Charging the capacitor C1 with L1, the current of the input inductor L1 decreases linearly; DS6, S6 and the load form a closed loop, and the current flowing through the filter inductor also linearly decreases.
5. The non-isolated boost inverter of claim 1, wherein the input side current of the inverter is continuous, the capacitor is primarily operative to transfer energy, and the voltage across the capacitor cannot be suddenly changed after the circuit has reached a steady state.
6. The non-isolated boost inverter circuit of claim 1, wherein the control method is simple and fewer switching tubes are operated in a high frequency state.
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| CN201910508590.1A CN110071651B (en) | 2019-06-13 | 2019-06-13 | Non-isolated boost inverter circuit with symmetrical structure |
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| CN201910508590.1A CN110071651B (en) | 2019-06-13 | 2019-06-13 | Non-isolated boost inverter circuit with symmetrical structure |
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| CN110071651B true CN110071651B (en) | 2023-05-12 |
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| CN112039363B (en) * | 2020-09-18 | 2022-04-26 | 常州大学 | Boost type voltage-free drop switch capacitor inverter |
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