CN218867922U - Hybrid power supply system and air conditioner - Google Patents

Abstract

The utility model discloses a mix power supply system and air conditioner, this system includes: the photovoltaic anode of the solar photovoltaic module is connected to the first input end of the first boosting module after passing through the first switch module; the output end of the first boosting module is connected to the first input end of the second boosting module; the photovoltaic cathode of the solar photovoltaic component is connected to the second input end of the first boosting module; after the alternating current commercial power passes through the second switch module and the rectifying module, the first output end of the rectifying module is connected to the first input end of the second boosting module; the first output end of the second boosting module is connected to the anode of the bus capacitor unit; the second output end of the rectifying module is connected to the first input end of the second boosting module on the one hand, and is connected to the negative electrode of the bus capacitor unit and grounded on the other hand. According to the scheme, the boost circuit of the solar photovoltaic power supply is connected in series with the boost circuit of the commercial power supply system, so that the utilization rate of the boost circuit of the alternating-current commercial power supply is improved.

Description

Hybrid power supply system and air conditioner

Technical Field

The utility model belongs to the technical field of the power supply, concretely relates to mix power supply system and air conditioner especially relates to an idle call mix power supply circuit (like the mix power supply circuit of the mixed power supply system that solar air conditioner, inverter air conditioner used) and air conditioner.

Background

In order to protect the environment and save energy, clean and renewable solar energy is applied to the air conditioner. In related schemes, the air conditioning technology of commercial power and photovoltaic hybrid power supply is more, and the hybrid power supply mode adopted by the schemes is to directly integrate a photovoltaic power generation grid-connected system into the direct current side of an air conditioning power supply system with mature technology and form a hybrid power supply system with the commercial power.

However, in the above scheme, the commercial power and the solar photovoltaic power supply both have separate boost circuits, and in the scene that the solar power supply energy is enough, the air conditioner only needs solar power supply and does not need alternating commercial power supply, the boost circuit of the alternating current commercial power supply is idle and does not work, and at least, the problem of low utilization rate of the boost circuit of the alternating current commercial power supply exists.

The above is only for the purpose of assisting understanding of the technical solutions of the present invention, and does not represent an admission that the above is the prior art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a mix power supply system and air conditioner, in order to solve in the scheme of commercial power and the mixed power supply of solar photovoltaic power supply, directly incorporate photovoltaic power generation grid-connected system into the direct current side of commercial power supply system, constitute mixed power supply system with the commercial power, under the scene that does not need alternating current mains power supply, alternating current mains power supply's boost circuit is idle out of work, the problem that there is alternating current mains power supply's boost circuit utilization ratio not high at least, reach the boost circuit through making solar photovoltaic power supply's boost circuit and commercial power supply system's boost circuit and establish ties, in order to form solar photovoltaic power supply's two-stage boost circuit, the effect of alternating current mains power supply's boost circuit's utilization ratio can be promoted at least.

The utility model provides a hybrid power supply system, include: the system comprises a solar photovoltaic power supply, an alternating current commercial power supply and a bus capacitor unit; the solar photovoltaic power supply comprises: the solar photovoltaic module comprises a solar photovoltaic module, a first switch module and a first boosting module; the alternating current commercial power supply comprises: the rectifier module, the second switch module and the second boost module; the photovoltaic positive electrode of the solar photovoltaic module is connected to the first input end of the first boosting module after passing through the first switch module; the output end of the first boosting module is connected to the first input end of the second boosting module, so that the first boosting module and the second boosting module are connected in series to form a two-stage boosting module of the solar photovoltaic power supply; the photovoltaic cathode of the solar photovoltaic component is connected to the second input end of the first boosting module; after the alternating current commercial power passes through the second switch module and the rectifying module, the first output end of the rectifying module is connected to the first input end of the second boosting module; the first output end of the second boosting module is connected to the anode of the bus capacitor unit; the second output end of the second boosting module is connected to the negative electrode of the bus capacitor unit; and the second output end of the rectifying module is connected to the first input end of the second boosting module on one hand, and is connected to the negative electrode of the bus capacitor unit and grounded on the other hand.

In some embodiments, the first boost module comprises: the first inductor module, the first diode module and the first switch tube module; the photovoltaic voltage output by the solar photovoltaic module passes through the first switch module and the first inductance module to obtain a first boost voltage; the first boosting voltage is input to a collector of a first switching tube module in the first boosting module and is also input to an anode of the first diode module; after passing through the first diode module, obtaining a second boost voltage which is recorded as a photovoltaic boost voltage; the photovoltaic boosting voltage is output to the second boosting module from the cathode of the first diode module, is boosted again by the second boosting module and then is output to the anode of the bus capacitor unit, and the direct-current bus voltage of the hybrid power supply system is obtained.

In some embodiments, the second boost module comprises: the second inductance module, the second diode module and the second switch tube module; wherein, under the condition that the second switch module is closed, the alternating current commercial power outputs rectified voltage after passing through the second switch module and the rectification module: under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module exists, the rectified voltage and the photovoltaic boosted voltage obtained by boosting through the first boosting module are input to a collector of a second switching tube module in the second boosting module and are also input to an anode of the second diode module after passing through the second inductance module; after passing through the second diode module, the direct current bus voltage of the hybrid power supply system is obtained by outputting the direct current bus voltage from the cathode of the second diode module to the anode of the bus capacitor unit; under the condition that photovoltaic boosted voltage obtained by boosting of the first boosting module does not exist, the rectified voltage passes through the second inductance module, and then is input to a collector of a second switch tube module in the second boosting module and is also input to an anode of the second diode module; after passing through the second diode module, the direct current bus voltage of the hybrid power supply system is obtained by outputting the direct current bus voltage from the cathode of the second diode module to the anode of the bus capacitor unit; under the condition that the second switch module is turned off and under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module exists, the photovoltaic boosted voltage obtained by boosting through the first boosting module is input to a collector electrode of a second switch tube module in the second boosting module after passing through the second inductance module and is also input to an anode of the second diode module; and after passing through the second diode module, the direct current bus voltage of the hybrid power supply system is obtained by outputting the direct current bus voltage from the cathode of the second diode module to the anode of the bus capacitor unit.

With above-mentioned system phase-match, the utility model discloses another aspect provides an air conditioner, include: the hybrid power supply system described above.

Therefore, the proposal of the utility model aims at the first Boost circuit of the solar photovoltaic power supply and the second Boost circuit of the AC commercial power supply, the first Boost circuit connected with the solar photovoltaic power supply is connected to the rear of the rectifier bridge of the AC commercial power supply and the front of the second Boost circuit, when only the solar photovoltaic power supply supplies power, the first Boost circuit boosts a lower solar photovoltaic voltage VDC1 to a proper voltage VDC2, and then the second Boost circuit boosts the voltage VDC2 to a direct-current bus voltage VDC4; when the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously, the first Boost circuit boosts the solar photovoltaic voltage VDC1 to a voltage VDC2, the voltage VDC2 needs to be equal to the voltage VDC3 rectified by the alternating current commercial power after passing through a diode D1, and the second Boost circuit boosts the voltage VDC3 to a direct current bus voltage VDC4; therefore, the boost circuit of the solar photovoltaic power supply is connected in series with the boost circuit of the commercial power supply system to form a two-stage boost circuit of the solar photovoltaic power supply, and the utilization rate of the boost circuit of the alternating-current commercial power supply can be at least improved. Meanwhile, the boost multiple of the boost circuit of the solar photovoltaic power supply is reduced, and the cost is saved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention.

The technical solution of the present invention is further described in detail by the accompanying drawings and examples.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the hybrid power supply system of the present invention;

fig. 2 is a schematic diagram of a topology of an embodiment of the ac and photovoltaic hybrid power supply circuit according to the present invention;

fig. 3 is a schematic diagram of a working flow of the hybrid power supply of an embodiment of the ac and photovoltaic hybrid power supply circuit according to the present invention during startup;

fig. 4 is a schematic diagram of a working flow of a hybrid power supply operation according to an embodiment of the ac and photovoltaic hybrid power supply circuit of the present invention;

fig. 5 is a schematic flowchart illustrating an embodiment of a control method of a hybrid power supply system of an air conditioner according to the present invention;

fig. 6 is a schematic flow chart of an embodiment of a first process of the method of the present invention for controlling the hybrid power supply system of the air conditioner to operate after starting;

fig. 7 is a schematic flow chart of an embodiment of a method for controlling a power supply process according to photovoltaic power and load demand power when the photovoltaic power is greater than the power threshold;

fig. 8 is a schematic flowchart of an embodiment of a second process of controlling the hybrid power supply system of the air conditioner to operate after starting according to the method of the present invention;

fig. 9 is a schematic flow chart illustrating an embodiment of controlling a power supply process according to the photovoltaic power and the load demand power in the case where the maximum power point output power of the solar photovoltaic module and the photovoltaic power is less than or equal to the load demand power in the method of the present invention;

fig. 10 is a flowchart illustrating an embodiment of a third process of controlling the hybrid power supply system of the air conditioner to operate after starting according to the method of the present invention.

Detailed Description

To make the purpose, technical solution and advantages of the present invention clearer, the following will combine the embodiments of the present invention and the corresponding drawings to clearly and completely describe the technical solution of the present invention. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In consideration of the above, in the air conditioning technology of the commercial power and photovoltaic hybrid power supply of the related scheme, the photovoltaic power generation grid-connected system is directly incorporated into the direct current side of the air conditioning power supply system with mature technology, and forms a hybrid power supply system with the commercial power. However, since the commercial power and the solar photovoltaic power supply have separate boost circuits, when the solar power supply energy is enough, the air conditioner only needs solar power supply, and does not need alternating current commercial power supply, the boost circuit of the alternating current commercial power supply is idle and does not work, and at least, the problem of low utilization rate of the boost circuit of the alternating current commercial power supply exists.

Moreover, the solar photovoltaic power supply is limited by the number of photovoltaic components, the connection mode, the solar illumination intensity and other factors, and the output voltage range of the solar photovoltaic power supply greatly fluctuates and can be as low as 50V or less at least. The voltage required by driving the air-conditioning compressor is boosted from 50V (generally about 380V), the boosting multiple is large, a boosting circuit needs a large inductance, the duty ratio of a switching tube is also increased, the conduction power consumption is large, and the cost and the reliability are influenced.

Therefore, the utility model discloses a scheme provides a hybrid power supply system, specifically is a hybrid power supply circuit of hybrid power supply system that solar air conditioner, variable frequency air conditioner used to can promote alternating current mains power supply's boost circuit's utilization ratio at least.

According to the utility model discloses an embodiment provides a hybrid power supply system. Referring to fig. 1, a schematic diagram of an embodiment of the system of the present invention is shown. The hybrid power supply system may include: the solar photovoltaic power supply, the alternating current commercial power supply and a bus capacitor unit, wherein the bus capacitor unit is a bus capacitor C. The solar photovoltaic power supply comprises: the solar photovoltaic module, first switch module and first Boost module, first switch module is like switch K1, and first Boost module is like first Boost circuit, the multiple that steps up of first Boost module can be less than the settlement multiple that steps up. The alternating current commercial power supply comprises: the rectifier module, second switch module and second Boost module, second switch module for example switch K2, second Boost module for example second Boost circuit.

The photovoltaic anode of the solar photovoltaic module is connected to the first input end of the first boosting module after passing through the first switch module. The output end of the first boosting module is connected to the first input end of the second boosting module, so that the first boosting module and the second boosting module are connected in series to form a two-stage boosting module of the solar photovoltaic power supply. And the photovoltaic cathode of the solar photovoltaic component is connected to the second input end of the first boosting module.

And after the alternating current commercial power passes through the second switch module and the rectifying module, the first output end of the rectifying module is connected to the first input end of the second boosting module. The first output end of the second boosting module is connected to the anode of the bus capacitor unit; and the second output end of the second boosting module is connected to the negative electrode of the bus capacitor unit. And the second output end of the rectifying module is connected to the first input end of the second boosting module on one hand, and is connected to the negative electrode of the bus capacitor unit and grounded on the other hand.

Aiming at the air conditioning system with mixed power supply of commercial power and a solar power supply, under the scene that only solar power supply is needed and alternating commercial power supply is not needed, the boost circuit of the alternating commercial power supply is idle, so that the problem that the utilization rate of the boost circuit of the alternating commercial power supply is not high is solved. The utility model discloses a scheme provides a pair of hybrid power supply system, specifically a solar air conditioner, the hybrid power supply circuit of the hybrid power supply system that variable frequency air conditioner used, boost circuit (if first Boost circuit) through making solar photovoltaic power supply establishes ties with mains supply system's Boost circuit (if second Boost circuit), with the two-stage Boost circuit that forms solar photovoltaic power supply, at least, in commercial power and solar photovoltaic power hybrid power supply's scheme has been solved, directly incorporate into mains supply system's direct current side with photovoltaic power generation grid-connected system, constitute hybrid power supply system with the commercial power, under the scene that does not need alternating current mains supply, alternating current mains supply's Boost circuit is idle out of work, the problem that the Boost circuit utilization ratio is not high that has alternating current mains supply's at least.

Meanwhile, before a Boost circuit (such as a first Boost circuit) of the solar photovoltaic power supply is connected in series with a Boost circuit (such as a second Boost circuit) of a mains supply system, when the output voltage of the solar photovoltaic power supply is low, the Boost multiple of the Boost circuit of the solar photovoltaic power supply needs to be set higher, and the problems that the Boost circuit of the solar photovoltaic power supply needs a large-inductance inductor and the conduction power consumption of a switching tube is large exist. In the scheme of the utility model, because the Boost voltage-boosting circuit (such as the first Boost voltage-boosting circuit) of the solar photovoltaic power supply is connected in series with the Boost voltage-boosting circuit (such as the second Boost voltage-boosting circuit) of the commercial power supply system, the two-stage Boost circuit of the solar photovoltaic power supply can be formed, so that the Boost multiple of the Boost circuit of the solar photovoltaic power supply does not need to be large, the cost can be reduced, and the reliability of the Boost circuit of the solar photovoltaic power supply can be improved.

In some embodiments, the first boost module comprises: the inductor comprises a first inductor module such as an inductor L1, a first diode module such as a diode D1 and a first switch tube module such as a switch tube Q1.

The photovoltaic voltage (such as the voltage VDC 1) output by the solar photovoltaic module passes through the first switch module and the first inductance module to obtain a first boosting voltage (such as the voltage VDC 2). The first boost voltage is input to a collector of a first switching tube module in the first boost module, and is also input to an anode of the first diode module. And obtaining a second boost voltage after passing through the first diode module, and recording the second boost voltage as a photovoltaic boost voltage. The photovoltaic boosting voltage is output to the second boosting module from the cathode of the first diode module, is boosted again by the second boosting module and is output to the anode of the bus capacitor unit, and the direct-current bus voltage (such as voltage VDC 4) of the hybrid power supply system is obtained.

In some embodiments, the second boost module comprises: the inductor comprises a second inductor module, a second diode module and a second switch tube module, wherein the second inductor module is an inductor L2, the second diode module is a diode D2, and the second switch tube module is a switch tube Q2.

Wherein, when the second switch module is closed, the ac utility power outputs a rectified voltage (e.g. voltage VDC 3) after passing through the second switch module and the rectifying module:

under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module exists, the rectified voltage and the photovoltaic boosted voltage obtained by boosting through the first boosting module are input to a collector of a second switch tube module in the second boosting module and are also input to an anode of the second diode module after passing through the second inductance module. And after passing through the second diode module, the voltage is output to the anode of the bus capacitor unit from the cathode of the second diode module, so that the direct-current bus voltage (such as the voltage VDC 4) of the hybrid power supply system is obtained.

Under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module is not available, the rectified voltage is input to a collector of a second switching tube module in the second boosting module and is also input to an anode of the second diode module after passing through the second inductance module. And after passing through the second diode module, outputting the voltage from the cathode of the second diode module to the anode of the bus capacitance unit to obtain the direct-current bus voltage (such as voltage VDC 4) of the hybrid power supply system.

Under the condition that the second switch module is turned off and under the condition that the photovoltaic boosting voltage obtained by boosting of the first boosting module exists, the photovoltaic boosting voltage obtained by boosting of the first boosting module is input to a collector electrode of a second switch tube module in the second boosting module and is also input to an anode of the second diode module after passing through the second inductance module. And after passing through the second diode module, outputting the voltage from the cathode of the second diode module to the anode of the bus capacitance unit to obtain the direct-current bus voltage (such as voltage VDC 4) of the hybrid power supply system.

Fig. 2 is a schematic diagram of a topology structure of an embodiment of the ac and photovoltaic hybrid power supply circuit according to the present invention. As shown in fig. 2, the ac and photovoltaic hybrid power supply circuit includes: the solar photovoltaic power supply, the alternating current commercial power supply and the bus capacitor C. And a direct-current bus voltage VDC4 output by the bus capacitor C supplies power to a motor in the compressor after passing through the inverter.

Wherein, solar photovoltaic power includes: the photovoltaic module comprises a solar photovoltaic module, a switch K1 and a first Boost circuit. A first Boost voltage Boost circuit comprising: inductor L1, switching tube Q1 and diode D1. An alternating current mains power supply comprising: switch K2, rectifier bridge, and second Boost circuit. A second Boost voltage Boost circuit comprising: inductor L2, switching tube Q2 and diode D2. The solar photovoltaic component and the alternating current commercial power are external power supplies.

In the example shown in fig. 2, the solar photovoltaic module supplies power to the air conditioner, the photovoltaic voltage output by the solar photovoltaic module is VDC1, the photovoltaic voltage firstly passes through a switch K1, and the switch K1 may be a dc contactor, a dc relay, or the like. The other end of the switch K1 (i.e., the end of the switch K1 away from the solar photovoltaic module) is connected to the first Boost circuit. The first Boost circuit comprises an inductor L1, a diode D1 and a switching tube Q1. The first Boost circuit functions to Boost the photovoltaic voltage VDC1 to a voltage VDC2 while performing a maximum power tracking algorithm.

The AC commercial power supplies power to the air conditioner, the AC commercial power firstly passes through a switch K2, and the switch K2 can be an AC contactor, an AC relay and the like. The other end of the switch K2 (i.e. the end of the switch K2 away from the ac mains) is connected to the rectifier bridge. The rectifier bridge outputs direct current with the voltage of VDC3. The other end of the rectifier bridge (i.e. the end of the rectifier bridge far away from the switch K2) is connected to the second Boost circuit. The second Boost circuit comprises an inductor L2, a diode D2 and a switching tube Q2. The second Boost circuit is used for boosting the rectified voltage VDC3 output by the rectifying bridge into a direct current bus voltage VDC4. The dc bus supplies power to an internal load of the air conditioner, such as a motor in a compressor, using the dc bus voltage VDC4. A capacitor with a large capacitance value (namely a direct-current bus capacitor C) is connected between the positive end and the negative end of the direct-current bus, and the direct-current bus capacitor C plays the roles of energy storage, voltage stabilization and filtering. The cathode of the diode D1 of the first Boost circuit is connected to the anode ("+" pole) of the output terminal of the rectifier bridge.

Thus, referring to the example shown in fig. 2, the first Boost circuit and the second Boost circuit are connected in series to form a two-stage Boost circuit of the solar photovoltaic power supply. Specifically, a first Boost circuit connected with a solar photovoltaic power supply is connected to the rear of a rectifier bridge of an alternating current commercial power supply and the front of a second Boost circuit, so that the solar photovoltaic power supply forms a two-stage Boost topological structure.

When only a solar photovoltaic power supply supplies power, the first Boost circuit boosts a lower solar photovoltaic voltage VDC1 to a suitable voltage VDC2 (such as 200 VDC), and then the second Boost circuit boosts the voltage VDC2 to a dc bus voltage VDC4 (generally 380 VDC). Under the working state, the boosting multiples (or boosting ratios) of the first Boost circuit and the second Boost circuit are lower than the boosting multiples of the solar photovoltaic voltage VDC1 boosted to the direct-current bus voltage VDC4 only by the first Boost circuit, so that the reliability of the hybrid power supply circuit is improved.

When the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously, the first Boost circuit boosts the solar photovoltaic voltage VDC1 to a voltage VDC2, the voltage VDC2 needs to be equal to the voltage VDC3 (generally 260 VDC-320 VDC) rectified by the alternating current commercial power after passing through the diode D1, and the second Boost circuit boosts the voltage VDC3 to a direct current bus voltage VDC4. Under the working state, the boosting multiple of the first Boost circuit is lower than that of the first Boost circuit for boosting the photovoltaic voltage VDC1 to the direct-current bus voltage VDC4, so that the reliability of the hybrid power supply circuit is improved.

Adopt the technical scheme of the utility model, first Boost voltage circuit and the second Boost voltage circuit of alternating current mains supply to solar photovoltaic power supply, with the first Boost voltage circuit that solar photovoltaic power supply connects, connect to after alternating current mains supply's the rectifier bridge and before the second Boost voltage circuit, in order to establish ties first Boost voltage circuit and second Boost voltage circuit, form photovoltaic power supply's two-stage voltage Boost circuit, when only solar photovoltaic power supply supplies power, first Boost voltage circuit will step up lower solar photovoltaic voltage VDC1 to suitable voltage VDC2 earlier, then rethread second Boost voltage Boost circuit steps up voltage VDC2 to direct current bus voltage VDC4. When the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously, the first Boost circuit boosts the solar photovoltaic voltage VDC1 to a voltage VDC2, the voltage VDC2 needs to be equal to a voltage VDC3 rectified by the alternating current commercial power after passing through the diode D1, and the second Boost circuit boosts the voltage VDC3 to a direct current bus voltage VDC4. Therefore, the boost circuit of the solar photovoltaic power supply is connected in series with the boost circuit of the commercial power supply system to form a two-stage boost circuit of the solar photovoltaic power supply, and the utilization rate of the boost circuit of the alternating-current commercial power supply can be at least improved. Meanwhile, the boost multiple of the boost circuit of the solar photovoltaic power supply is reduced, and the cost is saved.

According to the utility model discloses an embodiment still provides an air conditioner corresponding to hybrid power supply system. The air conditioner may include: the hybrid power supply system described above.

Since the processing and functions of the air conditioner of this embodiment are basically corresponding to the embodiments, principles and examples of the system, reference may be made to the related descriptions in the foregoing embodiments for details which are not described herein in this embodiment.

Adopt the technical scheme of the utility model, first Boost voltage circuit and the second Boost voltage circuit of alternating current mains supply to solar photovoltaic power supply, with the first Boost voltage circuit that solar photovoltaic power supply connects, connect to after alternating current mains supply's the rectifier bridge and before the second Boost voltage circuit, in order to establish ties first Boost voltage circuit and second Boost voltage circuit, form photovoltaic power supply's two-stage voltage Boost circuit, when only solar photovoltaic power supply supplies power, first Boost voltage circuit will step up lower solar photovoltaic voltage VDC1 to suitable voltage VDC2 earlier, then rethread second Boost voltage Boost circuit steps up voltage VDC2 to direct current bus voltage VDC4. When the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously, the first Boost circuit boosts the solar photovoltaic voltage VDC1 to a voltage VDC2, the voltage VDC2 needs to be equal to a voltage VDC3 rectified by the alternating current commercial power after passing through the diode D1, the second Boost circuit boosts the voltage VDC3 to a direct current bus voltage VDC4, the Boost multiple of the first Boost circuit to the photovoltaic voltage can be reduced, and the utilization rate of the second Boost circuit is improved. The reliability of the hybrid power supply circuit is improved.

According to the embodiment of the present invention, there is also provided a control method of a hybrid power supply system of an air conditioner corresponding to the air conditioner, as shown in fig. 5. The control method of the hybrid power supply system of the air conditioner may include: the process of controlling the start of the hybrid power supply system of the air conditioner may specifically include: step S110 to step S150.

At step S110, when the hybrid power supply system of the air conditioner is started, the second switch module is controlled to be closed, so as to start the ac mains supply.

At step S120, a photovoltaic voltage (e.g., a voltage VDC 1) output by the solar photovoltaic module is obtained.

At step S130, it is determined whether the photovoltaic voltage output by the solar photovoltaic module is greater than a set voltage threshold (e.g., a voltage threshold Vst).

In step S140, if it is determined that the photovoltaic voltage output by the solar photovoltaic module is greater than the voltage threshold, the first switch module is controlled to be closed to start the solar photovoltaic power supply to supply power. And controlling at least one of the switching frequency and the duty ratio of a first switching tube module in the first boosting module so as to boost the photovoltaic voltage output by the solar photovoltaic module to a first boosting voltage, wherein the first boosting voltage is greater than the photovoltaic voltage output by the solar photovoltaic module and less than the direct-current bus voltage of the hybrid power supply system. And at the same time, controlling at least one of the switching frequency and the duty ratio of a second switching tube module in the second boosting module, so that the rectified voltage output by the rectifying module and a second boosted voltage output by the second boosting module based on the first boosted voltage are boosted to the direct-current bus voltage of the hybrid power supply system and supplied to an electric load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being powered by the commercial power alternating-current power supply and the solar photovoltaic power supply together.

In step S150, if it is determined that the photovoltaic voltage output by the solar photovoltaic module is less than or equal to the voltage threshold, the second switch module is kept closed, the first switch module is kept open, and at least one of the switching frequency and the duty ratio of the second switch tube module in the second boost module is controlled, so that the rectified voltage output by the rectifier module is boosted to the dc bus voltage of the hybrid power supply system and is supplied to an electrical load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being powered only by the commercial power alternating-current power supply.

Fig. 3 is a schematic diagram of a working flow of the hybrid power supply of an embodiment of the ac and photovoltaic hybrid power supply circuit when starting up. The following describes an exemplary control method for hybrid power supply of the ac and photovoltaic hybrid power supply circuit, with reference to the examples shown in fig. 2 and 3. As shown in fig. 3, the hybrid ac and photovoltaic power supply circuit shown in fig. 2, a hybrid power supply control method at startup, includes:

and 11, when the solar photovoltaic module is started, closing the switch K2, and detecting the output voltage VDC1 of the solar photovoltaic module through the voltage detection circuit, wherein the output voltage VDC1 is recorded as the photovoltaic voltage VDC1.

Step 12, judging whether the photovoltaic voltage VDC1 is larger than a set voltage threshold value Vst: if yes, go to step 13, otherwise go to step 14.

And step 13, the photovoltaic voltage VDC1 is larger than a set voltage threshold value Vst, the solar photovoltaic module can supply power, and the switch K1 is closed. The solar photovoltaic voltage VDC1 is boosted to a voltage VDC2 by controlling the switching frequency and the duty ratio of the switching tube Q1. The voltage of the voltage VDC2 minus the voltage drop of the diode D1 is the voltage VDC3. The voltage VDC3 should be equal to or higher than the voltage of the ac mains after rectification by the rectifier bridge. The voltage VDC3 is boosted to the dc bus voltage VDC4 by controlling the switching frequency and the duty ratio of the switching tube Q2.

And 14, when the photovoltaic voltage VDC1 is smaller than the set voltage threshold value Vst, the solar photovoltaic module cannot supply power, and the switch K1 is switched off. And the alternating-current commercial power is rectified by the rectifier bridge to obtain rectified voltage VDC3, and the rectified voltage VDC3 supplies power to the direct-current bus after passing through the second Boost voltage boosting circuit to obtain direct-current bus voltage VDC4 of the hybrid power supply system. And the direct-current bus voltage VDC4 is output by controlling the switching frequency and the duty ratio of the switching tube Q2.

In some embodiments, the control method of the hybrid power supply system of an air conditioner according to the aspect of the present invention further includes: the method comprises a first process of controlling the hybrid power supply system of the air conditioner to run after starting, in particular to a process of controlling whether state switching is carried out or not in a state 1.

Referring to fig. 6, an embodiment of a flowchart of a first process of the hybrid power supply system of the air conditioner after being started according to the method of the present invention is further described, where the first process of the hybrid power supply system of the air conditioner after being started includes: step S210 to step S250.

Step S210, after the hybrid power supply system of the air conditioner is started, determining the load demand power of the air conditioner. For example: and calculating the power Pout required by the whole air conditioner according to the target frequency of the compressor in the air conditioner, and recording the power Pout as the load required power Pout.

Step S220, using an MPPT algorithm to control at least one of a switching frequency and a duty ratio of a first switching tube module in the first boost module, so that the solar photovoltaic module outputs power at a set maximum power point. And under the condition that the solar photovoltaic component outputs power at the maximum power point, determining the maximum power which can be output by the solar photovoltaic component, and recording as photovoltaic power (such as power Pdc). Specifically, determining the maximum power that the solar photovoltaic module can output, which is denoted as photovoltaic power (e.g., power Pdc), includes: under the condition that the solar photovoltaic component outputs power at the maximum power point, acquiring photovoltaic voltage (such as voltage VDC 1) output by the solar photovoltaic component, and acquiring photovoltaic current (such as current I1) output by the solar photovoltaic component. And under the condition that the solar photovoltaic module outputs power at the maximum power point, determining the maximum power which can be output by the solar photovoltaic module according to the photovoltaic voltage output by the solar photovoltaic module and the photovoltaic current output by the solar photovoltaic module, and recording the maximum power as photovoltaic power (such as power Pdc).

Step S230, determining whether the photovoltaic power of the solar photovoltaic module is greater than a set power threshold.

Step S240, if it is determined that the photovoltaic power of the solar photovoltaic module is less than or equal to the power threshold, under the condition that the first switch module is closed, controlling the first switch module to be opened, so as to control at least one of a switching frequency and a duty ratio of a second switch tube module in the second boost module, so that the rectified voltage output by the rectifier module is boosted to a dc bus voltage of the hybrid power supply system, and is supplied to an electric load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being powered only by the commercial power alternating-current power supply.

Step S250, if the photovoltaic power of the solar photovoltaic assembly is determined to be larger than the power threshold, controlling the operation process of the hybrid power supply system according to the photovoltaic power of the solar photovoltaic assembly and the load demand power of the air conditioner. At this time, the hybrid power supply system works in a working state of supplying power by the commercial power alternating current power supply and the solar photovoltaic power supply together.

Fig. 4 is a schematic diagram illustrating a working flow of the hybrid power supply operation according to an embodiment of the ac and photovoltaic hybrid power supply circuit of the present invention. When the hybrid ac and photovoltaic power supply circuit shown in fig. 2 operates, the hybrid ac and photovoltaic power supply circuit shown in fig. 2 may operate in any one of state 1, state 2, and state 3. The state 1 is a state in which the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously. And the state 2 is a state that the solar photovoltaic power supply supplies power independently and supplies power to the direct current bus through the first Boost circuit and the second Boost circuit. And the state 3 is a state that the alternating current commercial power supply supplies power independently and supplies power to the direct current bus through the second Boost circuit.

As shown in fig. 4, the ac and photovoltaic hybrid power supply circuit shown in fig. 2, a hybrid power supply control method during operation, includes:

step 21, under the condition that the electric load of the alternating current and photovoltaic hybrid power supply circuit shown in fig. 2 is an air conditioner (such as a variable frequency air conditioner), calculating the power Pout required by the complete air conditioner according to the target frequency of the compressor operation in the variable frequency air conditioner, and recording the power Pout as the load required power Pout.

Step 22, judging whether the air conditioner operates in a state 1, a state 2 or a state 3 according to the working states of the switching tube Q1 and the switching tube Q2: when the air conditioner is operated in the state 1 (i.e. the state that the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously), the steps 23 to 28 are entered. When the air conditioner is operated in the state 2 (i.e., the state in which the solar photovoltaic power supply is solely supplied with power), the flow proceeds to steps 29 to 35. When the air conditioner is operated in the state 3 (i.e., the state where the ac mains is supplied alone), steps 36 to 39 are entered.

As shown in fig. 4, the hybrid ac and photovoltaic power supply circuit shown in fig. 2 further includes:

when the air conditioner is operated in the state 1 (i.e., the state where the solar photovoltaic power supply and the ac commercial power supply are simultaneously supplied with power), steps 23 to 28 are performed. And 23, controlling the switching frequency and the duty ratio of the switching tube Q1 by using a maximum power point tracking algorithm, so that the photovoltaic module outputs power at the maximum power point. And calculating the maximum power Pdc which can be output by the solar photovoltaic assembly according to the photovoltaic voltage VDC1 and the current I1 output by the solar photovoltaic assembly, and recording the maximum power Pdc as photovoltaic power Pdc.

Step 24, comparing the photovoltaic power Pdc with a set power threshold Pst, specifically, judging whether the photovoltaic power Pdc is smaller than the set power threshold Pst: if so, step 25 is performed, otherwise, step 26 is performed.

And step 25, if the photovoltaic power Pdc is smaller than the set power threshold Pst, judging that the output energy of the solar photovoltaic power supply is insufficient, and turning off the solar photovoltaic power supply. Firstly, the switch tube Q1 is controlled not to work, then the switch K1 is disconnected, and the operation is switched to a state 3 (namely, the state of independent power supply of the alternating current commercial power supply). The rectified voltage VDC3 output by the rectified AC mains supply is boosted into the DC bus voltage VDC4 by controlling the switching frequency and the duty ratio of the switching tube Q2.

And step 26, if the photovoltaic power Pdc is larger than or equal to the set power threshold Pst, comparing the photovoltaic power Pdc with the load required power Pout.

In some embodiments, in the case that the photovoltaic power of the solar photovoltaic module is greater than the power threshold in step S250, a specific process of an operation process of the hybrid power supply system is controlled according to the photovoltaic power of the solar photovoltaic module and the load demand power of the air conditioner, as shown in the following exemplary description.

Referring to fig. 7, the method of the present invention further illustrates a specific process of controlling the power supply process according to the photovoltaic power and the load demand power in the step S250 when the photovoltaic power is greater than the power threshold, including: step S310 to step S330.

Step S310, under the condition that the photovoltaic power of the solar photovoltaic assembly is larger than the power threshold, determining whether the photovoltaic frequency of the solar photovoltaic assembly is larger than the load demand power of the air conditioner.

Step S320, under the condition that the photovoltaic power of the solar photovoltaic module is greater than the power threshold, if it is determined that the photovoltaic frequency of the solar photovoltaic module is greater than the load demand power of the air conditioner, under the condition that a second switch tube module in the second boost module operates, after the second switch tube module in the second boost module is controlled to stop operating, the second switch module is controlled to be turned off, so that the second boost voltage boosted by the first boost module is used as the dc bus voltage to the hybrid power supply system and is supplied to the electric load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being independently powered by the solar photovoltaic power supply.

Step S330, under the condition that the photovoltaic power of the solar photovoltaic module is greater than the power threshold, if the photovoltaic frequency of the solar photovoltaic module is determined to be less than or equal to the load demand power of the air conditioner, maintaining the first switch module to be closed and maintaining the second switch module to be both closed, determining the commercial power of the alternating current commercial power supply, and cooperatively controlling at least one of the switching frequency and the duty ratio of the first switch tube module in the first boost module and the second switch tube module in the second boost module, so that the sum of the photovoltaic power of the solar photovoltaic module and the commercial power of the alternating current commercial power supply is greater than or equal to the load demand power of the air conditioner. At this time, the hybrid power supply system works in a working state of supplying power by the commercial power alternating current power supply and the solar photovoltaic power supply together.

As shown in fig. 4, the ac and photovoltaic hybrid power supply circuit shown in fig. 2 further includes:

in step 26, specifically, it is determined whether the photovoltaic power Pdc is greater than the load required power Pout: if so, go to step 27, otherwise go to step 28.

And 27, if the photovoltaic power Pdc is larger than the load required power, only the solar photovoltaic power supply is needed to supply power, and the alternating current commercial power supply is not needed to supply power, firstly controlling the switch tube Q2 not to work, then disconnecting the switch K2, and switching to the state 2 (namely the state of independent power supply of the solar photovoltaic power supply).

And step 28, if the photovoltaic power Pdc is less than or equal to the load required power, maintaining the state 1 (namely, the state that the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously). And calculating power Pac output by the alternating current mains supply according to rectified voltage VDC3 output by the alternating current mains supply after passing through the rectifier bridge and current I2 output by the alternating current mains supply after passing through the rectifier bridge, and recording the power Pac as mains supply power Pac. By coordinately controlling the switching frequency and the duty ratio of the switching tube Q1 and the switching tube Q2, the photovoltaic power Pdc plus the commercial power Pac is equal to or greater than the load demand power Pout.

In some embodiments, the control method of the hybrid power supply system of an air conditioner according to the present invention further includes: and controlling a second process of the hybrid power supply system of the air conditioner to run after starting, specifically controlling whether to switch the state in the state 2.

Referring to fig. 8, an embodiment of a flowchart of a second process of the hybrid power supply system of the air conditioner after being started according to the method of the present invention is further described, where the specific process of the second process of the hybrid power supply system of the air conditioner after being started includes: step S410 to step S450.

And step S410, after the hybrid power supply system of the air conditioner is started, determining the load demand power of the air conditioner. For example: and calculating the power Pout required by the whole air conditioner according to the target frequency of the operation of the compressor in the air conditioner, and recording the power Pout as load required power Pout.

Step S420, using an MPPT algorithm to control at least one of a switching frequency and a duty ratio of a first switching tube module in the first boost module, so that the solar photovoltaic module outputs power at a set maximum power point. And under the condition that the solar photovoltaic component outputs power at the maximum power point, determining the maximum power which can be output by the solar photovoltaic component, and recording the maximum power as photovoltaic power (such as power Pdc). Specifically, determining the maximum power that the solar photovoltaic module can output, which is denoted as photovoltaic power (e.g., power Pdc), includes: under the condition that the solar photovoltaic component outputs power at the maximum power point, acquiring photovoltaic voltage (such as voltage VDC 1) output by the solar photovoltaic component, and acquiring photovoltaic current (such as current I1) output by the solar photovoltaic component. And under the condition that the solar photovoltaic module outputs power at the maximum power point, determining the maximum power which can be output by the solar photovoltaic module according to the photovoltaic voltage output by the solar photovoltaic module and the photovoltaic current output by the solar photovoltaic module, and recording the maximum power as photovoltaic power (such as power Pdc).

Step S430, determining whether the photovoltaic frequency of the solar photovoltaic module is greater than the load demand power of the air conditioner under the condition that the solar photovoltaic module outputs power at the maximum power point.

Step S440, under the condition that the solar photovoltaic module outputs power at the maximum power point, if it is determined that the photovoltaic frequency of the solar photovoltaic module is greater than the load demand power of the air conditioner, under the condition that the first switch module and the second switch module are both turned on, controlling the second switch module to be turned off, and at the same time, controlling at least one of the switching frequency and the duty ratio of the first switch tube module in the first boost module, so that the first boost module outputs a second boost voltage based on the photovoltaic voltage boost voltage of the solar photovoltaic module, and controlling at least one of the switching frequency and the duty ratio of the second switch tube module in the second boost module, so that the second boost module boosts the dc bus voltage of the hybrid power supply system based on the second boost voltage output by the first boost voltage, and supplies the dc bus voltage to an electric load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being independently powered by the solar photovoltaic power supply. In this case, the second boost voltage, for example, VDC3 obtained based on VDC2, is between the photovoltaic voltage VDC1 and the dc bus voltage VDC4.

Step S450, under the condition that the solar photovoltaic module outputs power at the maximum power point, if the photovoltaic frequency of the solar photovoltaic module is determined to be smaller than or equal to the load demand power of the air conditioner, the operation process of the hybrid power supply system is further controlled according to the photovoltaic power of the solar photovoltaic module and the load demand power of the air conditioner.

As shown in fig. 4, the ac and photovoltaic hybrid power supply circuit shown in fig. 2 further includes:

when the air conditioner is operated in the state 2 (i.e., the state in which the solar photovoltaic power source is supplied with power alone), steps 29 to 35 are performed. And 29, controlling the switching frequency and the duty ratio of the switching tube Q1 by using a maximum power point tracking algorithm to enable the solar photovoltaic module to output power at the maximum power point, and calculating the maximum power Pdc which can be output by the photovoltaic module according to the photovoltaic voltage VDC1 and the current I1 output by the solar photovoltaic module and recording the maximum power Pdc as photovoltaic power Pdc.

Step 30, comparing the photovoltaic power Pdc with the load required power Pout, specifically, judging whether the photovoltaic power Pdc is greater than the load required power Pout: if so, step 31 is performed, otherwise, step 33 is performed.

And step 31, if the photovoltaic power Pdc is greater than the load required power Pout, switching off the switch K2, and maintaining the state 2. The photovoltaic voltage VDC1 is boosted to a voltage VDC3 by controlling the switching frequency and the duty ratio of the switching tube Q1. In the operating state 2, the voltage VDC3 is a value between the photovoltaic voltage VDC1 and the dc bus voltage VDC4, which is set for the control logic. For example: the dc bus voltage VDC4 is 380VDC, and when the photovoltaic voltage VDC1 is 50VDC, the voltage VDC3 may be set to 150VDC. Or the dc bus voltage VDC4 is 380VDC, and when the photovoltaic voltage VDC1 is 200VDC, the voltage VDC3 may be set to 300VDC, after which step 32 is performed.

And step 32, boosting the voltage VDC3 to the voltage VDC4 of the direct-current bus by controlling the switching frequency and the duty ratio of the switching tube Q2.

In some embodiments, in step S450, in the case that the solar photovoltaic module outputs power at the maximum power point and the photovoltaic frequency of the solar photovoltaic module is less than or equal to the load demand power of the air conditioner, a specific process of an operation process of the hybrid power supply system is further controlled according to the photovoltaic power of the solar photovoltaic module and the load demand power of the air conditioner, see the following exemplary description.

The following description, with reference to fig. 9, illustrates an embodiment of a flow diagram of a power supply process controlled according to photovoltaic power and load demand power under the condition that the maximum power point output power of the solar photovoltaic module and the photovoltaic power are less than or equal to the load demand power in the method of the present invention, further explaining a specific process of controlling the power supply process according to the photovoltaic power and the load demand power under the condition that the maximum power point output power of the solar photovoltaic module and the photovoltaic power are less than or equal to the load demand power in step S450, including: step S510 to step S530.

Step S510, controlling at least one of a switching frequency and a duty ratio of a first switching tube module in the first boost module, so that the first boost module outputs a second boost voltage based on the photovoltaic voltage boost voltage of the solar photovoltaic module, and after the second boost voltage is greater than the rectified voltage output by the rectifying module, the second switching module is controlled to be turned on when the second switching module is turned off.

Step S520, controlling at least one of a switching frequency and a duty ratio of a first switching tube module in the first boost module, so that the first boost module outputs a second boost voltage based on the photovoltaic voltage boost voltage of the solar photovoltaic module, and the rectified current output by the rectifier module can be increased according to a set mode to determine the commercial power of the ac commercial power supply.

Step S530, at least one of the switching frequency and the duty ratio of the first switching tube module in the first boost module and the second switching tube module in the second boost module is coordinately controlled, so that the sum of the photovoltaic power of the solar photovoltaic module and the utility power of the ac utility power supply is greater than or equal to the load demand power of the air conditioner. At this time, the hybrid power supply system works in a working state of supplying power by the commercial power alternating current power supply and the solar photovoltaic power supply together.

As shown in fig. 4, the ac and photovoltaic hybrid power supply circuit shown in fig. 2 further includes:

and step 33, when the air conditioner operates in the state 2 (namely, the state that the solar photovoltaic power supply supplies power independently), comparing the photovoltaic power Pdc with the load required power Pout, specifically, after judging whether the photovoltaic power Pdc is greater than the load required power Pout, if the photovoltaic power Pdc is less than or equal to the load required power Pout, the solar photovoltaic power supply and the alternating current commercial power supply are required to supply power simultaneously. Firstly, the switching frequency and the duty ratio of the switching tube Q1 are controlled to make the voltage VDC3 after the first Boost is higher than the voltage rectified by the alternating current mains supply, then the switch K2 is closed, and then step 34 is executed.

For example: the photovoltaic power supply is 100VDC, when the photovoltaic power supply runs in a state 2, the first voltage boosting module boosts 100VDC to 200VDC, and the second voltage boosting module boosts 200VDC to a bus voltage of 360VDC. At this time, the switching speed and the duty ratio of the switching tube Q2 of the second boosting module are both suitable for boosting 200VDC to 360VDC. If the switch K2 is directly closed at this time, the voltage 308VDC rectified by the ac mains supply instantaneously replaces the voltage 200VDC output by the first voltage boosting module, and the switching speed and the duty ratio of the switching tube Q2 are not adjusted in time in the future, so that the second voltage boosting module is out of control (the output voltage of the second voltage boosting module is too high).

And step 34, controlling the switching frequency and the duty ratio of the switching tube Q1 to enable the first Boost circuit to output a proper voltage VDC2, wherein the voltage VDC2 can gradually increase the current I2 output by the alternating current mains supply, and then executing step 35.

For example: first, the first voltage boosting module boosts the photovoltaic voltage to 310VDC, which is 308VDC higher than the rectified voltage of the ac mains, and then closes the switch K2, the ac mains supplies power, but at this time, the 308VDC is still lower than 310VDC, and the current I2 is still 0. The switching speed and the duty ratio of a switching tube Q1 of the first boosting module are reduced, so that the output voltage of the first boosting module is reduced to 308VDC and then gradually reduced to 300VDC, and the current I2 is gradually increased in the process. The purpose of increasing the current I2 is: the current I1 is the current provided by the photovoltaic power supply, and the current I2 is the current provided by the AC mains supply. Because the photovoltaic power Pdc is less than or equal to the load required power Pout, the solar photovoltaic power supply and the alternating current commercial power supply are required to supply power simultaneously, so increasing I2 is to increase the power Pac provided by the alternating current commercial power to the load.

And step 35, calculating the power Pac output by the mains supply according to the voltage VDC3 and the current I2, and recording the power Pac as the mains supply power Pac. By means of coordinated control of the switching frequency and the duty ratio of the switching tube Q1 and the switching tube Q2, the photovoltaic power Pdc plus the PacPac is equal to or greater than the load demand power Pout, and the vehicle runs in the state 1.

In some embodiments, the control method of the hybrid power supply system of an air conditioner according to the present invention further includes: and controlling a third process of the hybrid power supply system of the air conditioner to run after starting, specifically controlling whether to switch the state in the state 3.

With reference to fig. 10, an embodiment of a flowchart of a third process of the hybrid power supply system of the air conditioner after being started to operate according to the method of the present invention is further described, wherein the specific process of the third process of the hybrid power supply system of the air conditioner after being started to operate includes: step S610 to step S640.

Step S610, determining a load demand power of the air conditioner after a hybrid power supply system of the air conditioner is started. For example: and calculating the power Pout required by the whole air conditioner according to the target frequency of the compressor in the air conditioner, and recording the power Pout as the load required power Pout.

Step S620, acquiring a photovoltaic voltage (e.g., voltage VDC 1) output by the solar photovoltaic module.

And determining whether the photovoltaic voltage output by the solar photovoltaic module is greater than a set voltage threshold (such as a voltage threshold Vst).

Step S630, if it is determined that the photovoltaic voltage output by the solar photovoltaic module is greater than the voltage threshold, under a condition that the first switch module is turned off, controlling the first switch module to be turned on, and controlling at least one of a switching frequency and a duty ratio of a first switch tube module in the first boost module, so as to boost the photovoltaic voltage output by the solar photovoltaic module to a first boost voltage, so that a second boost voltage output by the first boost module based on the first boost voltage is greater than or equal to a rectified voltage output by the rectification module. At this time, the hybrid power supply system works in a working state of supplying power by the commercial power alternating current power supply and the solar photovoltaic power supply together.

Step S640, if it is determined that the photovoltaic voltage output by the solar photovoltaic module is less than or equal to the voltage threshold, controlling at least one of a switching frequency and a duty ratio of a second switching tube module in the second boost module, so that the rectified voltage output by the rectifying module is boosted to a dc bus voltage of the hybrid power supply system and supplied to an electrical load (such as a motor in a compressor) of the air conditioner. At this time, the hybrid power supply system works in a working state of being solely supplied with power by the commercial power alternating-current power supply.

As shown in fig. 4, the ac and photovoltaic hybrid power supply circuit shown in fig. 2, a hybrid power supply control method during operation, includes:

when the air conditioner is operated in the state 3 (i.e., the state where the ac commercial power is supplied alone), steps 36 to 39 are performed.

And step 36, detecting the output voltage VDC1 of the solar photovoltaic module through a voltage detection circuit, and recording as the photovoltaic voltage VDC1.

Step 37, comparing whether the photovoltaic voltage VDC1 is greater than a set voltage threshold Vst: if so, go to step 38, otherwise go to step 39.

And step 38, if the photovoltaic voltage VDC1 is larger than the set voltage threshold value Vst, the solar photovoltaic power supply can supply power, the switch K1 is closed, the switching frequency and the duty ratio of the switching tube Q1 are controlled, the photovoltaic voltage VDC1 is boosted to be a voltage VDC2, the voltage drop of the diode D1 subtracted from the voltage VDC2 is equal to or larger than a voltage VDC3, and then the operation of the state 1 is started.

And step 39, when the photovoltaic voltage VDC1 is less than or equal to the set voltage threshold value Vst, maintaining the state 3, controlling the switching frequency and the duty ratio of the switching tube Q2, and boosting the voltage VDC3 into a direct-current bus voltage VDC4.

The utility model discloses a scheme connects first Boost voltage circuit's diode D1 to after the rectifier bridge, before second Boost voltage circuit's inductance L2, forms the form of establishing ties with second Boost voltage circuit. Instead of the diode D1 of the first Boost circuit, is connected to the dc bus in parallel with the second Boost circuit. Therefore, the first Boost circuit and the second Boost circuit are connected in series to form a two-stage Boost circuit for the solar photovoltaic power supply, the photovoltaic power supply VDC1 is boosted to VDC3 through the first Boost circuit, and the photovoltaic power supply VDC4 is boosted through the second Boost circuit in sequence, the boosting multiple of the first Boost circuit on the photovoltaic voltage can be reduced, and the reliability of the hybrid power supply circuit is improved. In addition, the second Boost circuit is multiplexed with the direct-current voltage VDC3 rectified by the alternating-current mains supply and the direct-current voltage VDC2 boosted by the photovoltaic power supply, and the utilization rate of the second Boost circuit is improved.

Since the processing and functions implemented by the method of this embodiment substantially correspond to the embodiments, principles and examples of the air conditioner, reference may be made to the related descriptions in the foregoing embodiments without being detailed in the description of this embodiment.

By adopting the technical scheme of the embodiment, aiming at a first Boost circuit of a solar photovoltaic power supply and a second Boost circuit of an alternating current commercial power supply, the first Boost circuit connected with the solar photovoltaic power supply is connected to the rear of a rectifier bridge of the alternating current commercial power supply and the front of the second Boost circuit so as to connect the first Boost circuit and the second Boost circuit in series to form a two-stage Boost circuit of the photovoltaic power supply, when only the solar photovoltaic power supply supplies power, the first Boost circuit boosts a lower solar photovoltaic voltage VDC1 to a proper voltage VDC2, and then the second Boost circuit boosts the voltage VDC2 to a direct current bus voltage VDC4; when the solar photovoltaic power supply and the alternating current commercial power supply power simultaneously, the first Boost circuit boosts the solar photovoltaic voltage VDC1 to a voltage VDC2, the voltage VDC2 needs to be equal to a voltage VDC3 rectified by the alternating current commercial power after passing through the diode D1, and the second Boost circuit boosts the voltage VDC3 to a direct current bus voltage VDC4, so that the Boost multiple of the first Boost circuit is reduced, the cost is saved, and the reliability of the hybrid power supply circuit is also improved.

In conclusion, it is readily understood by those skilled in the art that the advantageous modes described above can be freely combined and superimposed without conflict.

The above description is only an example of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims (4)

1. A hybrid power supply system, comprising: the system comprises a solar photovoltaic power supply, an alternating current commercial power supply and a bus capacitor unit; the solar photovoltaic power supply comprises: the solar photovoltaic module, the first switch module and the first boosting module; the alternating current commercial power supply comprises: the rectifier module, the second switch module and the second boost module; wherein, the first and the second end of the pipe are connected with each other,

the photovoltaic anode of the solar photovoltaic module is connected to the first input end of the first boosting module after passing through the first switch module; the output end of the first boosting module is connected to the first input end of the second boosting module, so that the first boosting module and the second boosting module are connected in series to form a two-stage boosting module of the solar photovoltaic power supply; the photovoltaic cathode of the solar photovoltaic component is connected to the second input end of the first boosting module;

after the alternating current commercial power passes through the second switch module and the rectifying module, a first output end of the rectifying module is connected to a first input end of the second boosting module; the first output end of the second boosting module is connected to the anode of the bus capacitor unit; the second output end of the second boosting module is connected to the negative electrode of the bus capacitor unit; and the second output end of the rectifying module is connected to the first input end of the second boosting module on one hand, and is connected to the negative electrode of the bus capacitor unit and grounded on the other hand.

2. The hybrid power supply system of claim 1, wherein the first boost module comprises: the first inductor module, the first diode module and the first switch tube module; wherein, the first and the second end of the pipe are connected with each other,

photovoltaic voltage output by the solar photovoltaic module passes through the first switch module and the first inductance module to obtain first boosted voltage; the first boosting voltage is input to a collector of a first switching tube module in the first boosting module and is also input to an anode of the first diode module; after passing through the first diode module, obtaining a second boost voltage which is recorded as a photovoltaic boost voltage; the photovoltaic boosting voltage is output to the second boosting module from the cathode of the first diode module, is boosted again by the second boosting module and then is output to the anode of the bus capacitor unit, and the direct-current bus voltage of the hybrid power supply system is obtained.

3. The hybrid power supply system according to claim 1 or 2, wherein the second boost module comprises: the second inductor module, the second diode module and the second switch tube module; wherein the content of the first and second substances,

under the condition that the second switch module is closed, the alternating current commercial power outputs rectified voltage after passing through the second switch module and the rectification module:

under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module exists, the rectified voltage and the photovoltaic boosted voltage obtained by boosting through the first boosting module are input to a collector of a second switching tube module in the second boosting module and are also input to an anode of the second diode module after passing through the second inductance module; after passing through the second diode module, the direct current bus voltage of the hybrid power supply system is obtained by outputting the direct current bus voltage from the cathode of the second diode module to the anode of the bus capacitor unit;

under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module is not available, the rectified voltage is input to a collector of a second switching tube module in the second boosting module and is also input to an anode of the second diode module after passing through the second inductance module; after passing through the second diode module, the direct current bus voltage of the hybrid power supply system is obtained by outputting the direct current bus voltage from the cathode of the second diode module to the anode of the bus capacitor unit;

under the condition that the second switch module is turned off and under the condition that the photovoltaic boosted voltage obtained by boosting through the first boosting module exists, the photovoltaic boosted voltage obtained by boosting through the first boosting module is input to a collector electrode of a second switch tube module in the second boosting module after passing through the second inductance module and is also input to an anode of the second diode module; and after passing through the second diode module, outputting the voltage from the cathode of the second diode module to the anode of the bus capacitor unit to obtain the direct-current bus voltage of the hybrid power supply system.

4. An air conditioner, comprising: the hybrid power supply system according to any one of claims 1 to 3.

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