CN-122026738-A - Fourteen-hybrid-device air conditioner variable-frequency driving converter

CN122026738ACN 122026738 ACN122026738 ACN 122026738ACN-122026738-A

Abstract

The application belongs to the technical field of power electronics, and relates to a fourteen-hybrid-device air conditioner variable-frequency driving converter which comprises a three-phase topological circuit and a control system, wherein the three-phase topological circuit is identical in structure, the control system is used for generating driving signals of switching devices, the i-phase topological circuit comprises three voltage stabilizing capacitors and three switching circuits, the voltage stabilizing capacitors II are connected in series, the first switching circuit and the second switching circuit are connected in series, the first switching circuit and the voltage stabilizing capacitors II are connected with the positive electrode of a direct-current bus, the second switching circuit and the voltage stabilizing capacitors III are connected with the negative electrode of the direct-current bus, the first switching circuit and the second switching circuit both comprise two inductors and two series circuits formed by connecting an Si IGBT and an SiC SBD in series, the third switching circuit comprises two SiC MOSFETs, two inductors and two series circuits formed by connecting an SiC MOSFET and an SiC SBD in series, and the first switching circuit inductor and the second switching circuit are connected with the third switching circuit SiC MOSFET, and the third switching circuit inductor is connected with the i-phase of a permanent magnet synchronous motor. The application has high reliability and long service life.

Inventors

ZHAO RENDE
YAN QINGZENG
HE JINKUI
XU HAILIANG
MA WENZHONG
ZHANG LONGLONG
SUN BAIQIANG

Assignees

中国石油大学(华东)

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (10)

1. The utility model provides a fourteen hybrid device air conditioner variable frequency drive converter which characterized in that includes the three-phase topology circuit that the structure is the same entirely and is arranged in generating switching device drive signal's control system in the three-phase topology circuit, i phase topology circuit includes: the voltage stabilizing component comprises a voltage stabilizing capacitor I, a voltage stabilizing capacitor II and a voltage stabilizing capacitor III which are connected in series, wherein the voltage stabilizing capacitor II is connected with the positive electrode of the direct current bus, and the voltage stabilizing capacitor III is connected with the negative electrode of the direct current bus; The first switch circuit comprises a first inductor I, a first inductor II and two series circuits formed by connecting a Si IGBT and a SiC SBD in series, wherein the cathode of the Si SBD in the first series circuit I and the collector of the Si IGBT in the first series circuit II are both connected with the positive electrode of a direct current bus, the emitter of the Si IGBT in the first series circuit I and the anode of the SiC SBD in the first series circuit II are both connected with the connection point of a voltage stabilizing capacitor II and a voltage stabilizing capacitor III, the first end of the first inductor II is connected with the connection point of the Si IGBT collector and the SiC SBD anode in the first series circuit I, and the first end of the first inductor I is connected with the connection point of the Si IGBT emitter and the SiC SBD cathode in the first series circuit II; The second switch circuit comprises a second inductor I, a second inductor II and two series circuits formed by connecting an Si IGBT and an SiC SBD in series, wherein the anode of the Si SBD in the second series circuit I and the emitter of the Si IGBT in the second series circuit II are both connected with the cathode of a direct current bus, the collector of the Si IGBT in the second series circuit I and the cathode of the SiC SBD in the second series circuit II are both connected with the connection point of a voltage stabilizing capacitor II and a voltage stabilizing capacitor III, the first end of the second inductor II is connected with the connection point of the Si IGBT emitter and the SiC SBD cathode in the second series circuit I, and the first end of the second inductor I is connected with the connection point of the Si IGBT collector and the SiC SBD anode in the second series circuit II; The third switch circuit comprises SiC MOSFETI, siC MOSFETII, a third inductor I, a third inductor II and two series circuits formed by connecting a SiC MOSFET and a SiC SBD in series, wherein the drain electrode of SiC MOSFETI is connected with the second ends of the first inductor I and the first inductor II, the source electrode of SiC MOSFETII is connected with the second ends of the second inductor I and the second inductor II, the first end of a voltage stabilizing capacitor I, the cathode of the SiC SBD in the third series circuit I and the drain electrode of the SiC MOSFET in the third series circuit II are all connected with the source electrode of SiC MOSFETI, the second end of the voltage stabilizing capacitor I, the source electrode of the SiC MOSFET in the third series circuit I and the anode of the SiC SBD in the third series circuit II are all connected with the drain electrode of SiC MOSFETII, the first end of the third inductor II is connected with the connection point of the source electrode of the SiC MOSFET and the cathode of the SiC SBD in the third series circuit II, and the second ends of the third inductor I and the third inductor II are all connected with the I phases of the air conditioner, i=a, b and c.
2. The fourteen hybrid device air conditioner variable frequency drive inverter of claim 1, wherein the control system comprises: The acquisition module is used for acquiring the actual voltage of the I-phase voltage stabilizing capacitor I and the I-phase output current; the setting module is used for setting a carrier signal and an i-phase original modulated wave signal; The split modulation wave generation module is used for generating i-phase four different split modulation wave signals based on the i-phase original modulation wave signals; The combined modulation wave generation module is used for generating I-phase two combined modulation wave signals based on the actual voltage of the I-phase voltage stabilizing capacitor I, I-phase output current, I-phase original modulation wave signals and I-phase four split modulation wave signals; the driving signal generation module generates a driving signal of the Si IGBT in the i-phase topological circuit according to the size of the i-phase original modulation wave signal, and generates a driving signal of the SiC MOSFET in the i-phase topological circuit according to the sizes of the carrier signal and the i-phase combined modulation wave signal.
3. The fourteen-hybrid device air conditioner variable frequency drive converter of claim 2, wherein the split modulation wave generating module generates the i-phase first split modulation wave signal based on the i-phase original modulation wave signal by: judging whether the i-phase original modulated wave signal is larger than or equal to a first threshold value or not; When the i-phase original modulation wave signal is smaller than the first threshold value, obtaining a first intermediate signal as a second set value; And multiplying the first intermediate signal by a set coefficient to obtain an i-phase first split modulation wave signal.
4. The fourteen-hybrid air conditioner variable frequency drive converter of claim 2, wherein the split modulation wave generating module generates an i-phase second split modulation wave signal based on the i-phase original modulation wave signal by: Judging whether the i-phase original modulated wave signal is larger than or equal to a second threshold value; When the i-phase original modulation wave signal is larger than or equal to a second threshold value, obtaining a second intermediate signal which is the i-phase original modulation wave signal plus a first set value; And multiplying the second intermediate signal by a set coefficient, and obtaining an i-phase second split modulation wave signal through amplitude limiting.
5. The fourteen-hybrid device air conditioner variable frequency drive converter of claim 2, wherein the split modulation wave generating module generates an i-phase third split modulation wave signal based on the i-phase original modulation wave signal by: judging whether the i-phase original modulated wave signal is larger than or equal to a first threshold value or not; When the i-phase original modulated wave signal is smaller than the first threshold value, obtaining a third intermediate signal as the i-phase original modulated wave signal; and multiplying the third intermediate signal by a set coefficient, and obtaining an i-phase third split modulation wave signal through amplitude limiting.
6. The fourteen-hybrid device air conditioner variable frequency drive converter of claim 2, wherein the split modulation wave generating module generates an i-phase fourth split modulation wave signal based on the i-phase original modulation wave signal by: Judging whether the i-phase original modulated wave signal is larger than or equal to a second threshold value; When the i-phase original modulation wave signal is larger than or equal to the second threshold value, a fourth intermediate signal is obtained as a first set value; and multiplying the fourth intermediate signal by a set coefficient to obtain an i-phase fourth split modulation wave signal.
7. The fourteen-hybrid device air conditioner variable frequency driving converter of claim 2, wherein the method for generating the i-phase first combined modulation wave signal by the combined modulation wave generating module comprises the following steps: Judging whether the i-phase original modulated wave signal is more than or equal to 0; When the i-phase original modulation wave signal is smaller than 0, obtaining a first modulation signal as an i-phase second split modulation wave signal, and a second modulation signal as an i-phase fourth split modulation wave signal; judging whether the i-phase output current is greater than or equal to 0; when the i-phase output current is smaller than 0, obtaining a third modulation signal as a second modulation signal, and obtaining a fourth modulation signal as a first modulation signal; judging whether the actual voltage of the I-phase voltage stabilizing capacitor I is larger than or equal to a set voltage threshold value; When the actual voltage of the I-phase voltage stabilizing capacitor I is larger than or equal to a set voltage threshold, an I-phase first combined modulation wave signal is obtained to be a third modulation signal, and when the actual voltage of the I-phase voltage stabilizing capacitor I is smaller than the set voltage threshold, an I-phase first combined modulation wave signal is obtained to be a fourth modulation signal.
8. The fourteen-hybrid device air conditioner variable frequency driving converter according to claim 2, wherein the method for generating the i-phase second combined modulation wave signal by the combined modulation wave generating module comprises the steps of: Judging whether the i-phase original modulated wave signal is more than or equal to 0; when the i-phase original modulation wave signal is smaller than 0, obtaining a fifth modulation signal which is an i-phase second split modulation wave signal, and a sixth modulation signal which is an i-phase fourth split modulation wave signal; judging whether the i-phase output current is greater than or equal to 0; When the i-phase output current is smaller than 0, obtaining a seventh modulation signal as a fifth modulation signal, and obtaining an eighth modulation signal as a sixth modulation signal; judging whether the actual voltage of the I-phase voltage stabilizing capacitor I is larger than or equal to a set voltage threshold value; When the actual voltage of the I-phase voltage stabilizing capacitor I is larger than or equal to a set voltage threshold, an I-phase second combined modulation wave signal is obtained to be a seventh modulation signal, and when the actual voltage of the I-phase voltage stabilizing capacitor I is smaller than the set voltage threshold, an I-phase second combined modulation wave signal is obtained to be an eighth modulation signal.
9. The fourteen hybrid device air conditioner variable frequency drive converter of claim 2, wherein the method for generating the drive signal of the Si IGBT in the i-phase topology circuit by the drive signal generating module comprises: comparing the i-phase original modulation wave signal with 0; When the I-phase original modulation wave signal is greater than or equal to 0, a driving signal PWMI1 of Si IGBT in a first serial circuit II and a driving signal PWMI3 of Si IGBT in a second serial circuit I in the I-phase topological circuit are obtained to be high levels, a driving signal PWMI2 of Si IGBT in the first serial circuit I and a driving signal PWMI4 of Si IGBT in the second serial circuit II in the I-phase topological circuit are obtained to be low levels, and when the I-phase original modulation wave signal is smaller than 0, a driving signal PWMI1 of Si IGBT in the first serial circuit II and a driving signal PWMI3 of Si IGBT in the second serial circuit I in the I-phase topological circuit are obtained to be low levels, and a driving signal PWMI2 of Si IGBT in the first serial circuit I and a driving signal PWMI4 of Si IGBT in the second serial circuit II in the I-phase topological circuit are obtained to be high levels.
10. The fourteen hybrid device air conditioner variable frequency drive converter of claim 2, wherein the method for generating the driving signal of the SiC MOSFET in the i-phase topology circuit by the driving signal generating module comprises: comparing the carrier signal with the i-phase first combined modulated wave signal; When the i-phase first combined modulated wave signal is smaller than the carrier signal, a drive signal PWMI5 of SiC MOSFETI in the i-phase topological circuit is low level, and a drive signal PWMI6 of SiC MOSFETII is high level; Comparing the carrier signal with the i-phase second combined modulated wave signal; When the I-phase second combined modulation wave signal is greater than or equal to the carrier signal, a driving signal PWMI7 of the SiC MOSFET in the third serial circuit II in the I-phase topological circuit is high level, a driving signal PWMI8 of the SiC MOSFET in the third serial circuit I is low level, and when the I-phase second combined modulation wave signal is smaller than the carrier signal, a driving signal PWMI7 of the SiC MOSFET in the third serial circuit II in the I-phase topological circuit is low level, and a driving signal PWMI8 of the SiC MOSFET in the third serial circuit I is high level.

Description

Fourteen-hybrid-device air conditioner variable-frequency driving converter Technical Field The application belongs to the technical field of power electronics, relates to a variable frequency air conditioner control technology, and particularly relates to a fourteen-hybrid-device air conditioner variable frequency driving converter. Background Compared with the fixed-frequency air conditioner, the variable-frequency air conditioner has the remarkable advantages of energy conservation, accurate temperature control and low running noise, and becomes a main stream product of the modern energy-saving air conditioner. The variable frequency driving converter of the air conditioner is used as a core electric control component of the variable frequency air conditioner, is a key technical carrier for realizing variable frequency adjustment of the air conditioner, and the performance of the variable frequency driving converter of the air conditioner directly determines the energy saving effect, the running stability and the service life of an air conditioning system. The air conditioner variable frequency drive converter has the core function of converting 220V/50Hz power frequency alternating current input by a power grid into alternating current with adjustable frequency and voltage, so as to regulate the rotating speed of a compressor, realize accurate control of indoor temperature, further fully exert the technical advantages of a variable frequency air conditioner and ensure that an air conditioning system dynamically adapts to running power according to room temperature. The high-efficiency and long-life variable-frequency driving converter of the air conditioner is an important basis for long-term energy conservation and reliable operation of an air conditioning system, and the characteristics of a core power device of the variable-frequency driving converter of the air conditioner are key factors for restricting the performance improvement of the variable-frequency driving converter of the air conditioner. The existing traditional air conditioner variable frequency driving current transformer generally adopts a silicon-based insulated gate bipolar transistor (Silicon Insulated Gate Bipolar Transistor, si IGBT for short) as a core power device, however, the power device has inherent performance defects that on one hand, the Si IGBT has low switching speed and relatively large switching loss, the energy conversion efficiency of the air conditioner variable frequency driving current transformer is directly influenced, and the energy consumption of an air conditioning system is difficult to further reduce. On the other hand, the highest working temperature of the Si IGBT is lower, the heat dissipation design of the air conditioner variable frequency driving converter is strictly required, the structural design complexity of an air conditioner system is increased, and the working environment suitability of the air conditioner variable frequency driving converter is also limited. In order to solve the efficiency bottleneck of the Si IGBT-based converter, a silicon carbide metal Oxide semiconductor field effect transistor (Silicon Carbide Metal-Oxide-Semiconductor Field-Effect Transistor, called SiC MOSFET for short) is gradually adopted in the industry to replace the traditional Si IGBT, and the SiC MOSFET has the advantages of low switching loss and high tolerance working temperature, can effectively improve the energy conversion efficiency of the air conditioner variable frequency driving converter, simultaneously reduces the design requirement of a heat dissipation system of the air conditioner variable frequency driving converter, and meets the development requirements of energy conservation and miniaturization of the air conditioner system. On the one hand, the SiC MOSFET has extremely high switching speed, mutual interference is easily generated between devices which are complementarily turned on and off, direct-through short-circuit faults of the variable-frequency driving converter of the air conditioner are easily caused, the devices are irreparably damaged, and finally the whole air conditioning system is paralyzed and stopped. On the other hand, the high-speed switching characteristic enables the output voltage change rate (dv/dt) of the SiC MOSFET-based air conditioner variable frequency drive converter to be far higher than that of the traditional Si IGBT-based air conditioner variable frequency drive converter, and the high-voltage change rate (dv/dt) can greatly aggravate electromagnetic interference (Electro MAGNETIC INTERFERENCE, EMI for short) of an air conditioner system while reducing switching loss, so that normal operation of peripheral sensitive circuits in the air conditioner can be interfered, running stability of the whole air conditioner system can be influenced, and reliability of the air conditioner system is remarkably reduced. In summary, the existing air conditioner variable freque