Inverter sine wave soft compression method, system and storage medium

Abstract

The present invention provides a method, system and storage medium for inverter sinusoidal wave soft compression, the method comprising: obtaining the actual voltage value of high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output, judging whether the actual voltage value is less than the preset voltage peak value, if not, performing an inversion process of reducing the amplitude of the actual voltage value to obtain an inverter alternating current voltage; if less than, superimposing odd harmonics when performing the inversion process on the actual voltage value to obtain an inverter alternating current voltage. The present application can output a smooth alternating voltage that satisfies the requirement of not reducing the effective value at all times through simple calculations in embedded occasions.

Description

Technical Field

[0001] The present application relates to the technical field of voltage inversion, and in particular to a method, system and storage medium for soft compression of a sine wave of an inverter. Background Art

[0002] Most inverters on the market are DC-DC plus DC-AC two-stage structures. The front-stage DC-DC performs the boosting work, boosting the battery voltage to 200V-400V high-voltage DC, and then the rear-stage DC-AC inverts it into 110V or 220V AC. In order to ensure the efficiency of the power conversion of the front-stage DC-DC, the inverter usually does not stabilize the high-voltage DC, which makes the voltage of the high-voltage DC output by the front-stage DC-DC unstable.

[0003] When the battery power is reduced, the battery voltage is reduced, and the high-voltage DC voltage after boosting will also decrease. When the high-voltage DC voltage is lower than the peak voltage of the sine wave corresponding to the final output AC voltage, the AC voltage output by the inverter's rear-stage DC-AC will not reach the set value. In this case, it is necessary to compress the sine wave, and reduce the peak value of the sine wave while ensuring that the effective value of the sine wave corresponding to the final output AC voltage does not decrease, that is, reduce the peak voltage of the final output AC voltage.

[0004] At present, hard compression technology or soft compression technology is generally used. Among them, hard compression technology usually causes the sine wave corresponding to the output AC voltage to be clipped and distorted, which is not conducive to the subsequent carrying of inductive loads. In order to solve the problem of subsequent carrying of inductive loads, soft compression technology can be used, but at present, soft compression technology is usually complex in calculation and has a large amount of calculation, which may not be used in embedded occasions, or it needs to occupy a large amount of CPU resources when used. Summary of the invention

[0005] In order to output a smooth AC voltage without reducing the effective value at all times through simple calculations in embedded applications, the embodiments of the present application provide an inverter sinusoidal wave soft compression method, system and storage medium.

[0006] In a first aspect, this embodiment provides a method for inverter sine wave soft compression, the method comprising:

[0007] Obtaining the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output, determining whether the actual voltage value is less than the preset voltage peak value, and if not, performing an inversion process of reducing the amplitude of the actual voltage value to obtain an inverter alternating current voltage;

[0008] If it is less than, odd harmonics are superimposed when the actual voltage value is inverted to obtain an inverter AC voltage.

[0009] In some of the embodiments, the odd harmonic is a third harmonic.

[0010] In some embodiments, superimposing odd harmonics when inverting the actual voltage value to obtain an inverted AC voltage includes:

[0011] Subtracting the actual voltage value from the preset voltage peak value to obtain a voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic;

[0012] The actual voltage value is multiplied by the fundamental wave and added with the harmonic amplitude multiplied by the odd harmonic to obtain an AC voltage reference of the inverter AC power;

[0013] The AC voltage reference and the voltage PI loop are used to calculate to obtain the inverter AC voltage.

[0014] In some embodiments, the step of performing an inversion process on the actual voltage value to reduce the amplitude to obtain an inverted AC voltage includes:

[0015] Dividing the preset voltage peak value by the actual voltage value to obtain an amplitude gain coefficient;

[0016] Multiplying the actual voltage value by the fundamental wave and the amplitude gain coefficient to obtain an AC voltage reference of the inverter AC power;

[0017] The AC voltage reference and the voltage PI loop are used to calculate to obtain the inverter AC voltage.

[0018] In some embodiments, obtaining the actual voltage value of the high voltage direct current includes:

[0019] It is determined whether a PWM period interrupt signal is obtained. If so, a voltage value on the DC bus is obtained to obtain an actual voltage value of the high-voltage DC power.

[0020] In some embodiments, the actual voltage value is not lower than a preset reference voltage value.

[0021] In some of the embodiments, after the inverter AC voltage is obtained, an interruption end signal is also generated to end the PWM cycle interruption.

[0022] In a second aspect, this embodiment provides an inverter sine wave soft compression system, the system comprising: an acquisition module, a judgment module and a processing module; wherein:

[0023] The acquisition module is used to acquire the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output;

[0024] The judging module is used to judge whether the actual voltage value is less than the preset voltage peak value;

[0025] The processing module is used to, if it is not less than, perform an inversion process on the actual voltage value with a reduced amplitude to obtain an inverted AC voltage; if it is less than, superimpose odd harmonics when performing the inversion process on the actual voltage value to obtain an inverted AC voltage.

[0026] In some embodiments, the odd harmonic is a third harmonic, and superimposing the odd harmonic when inverting the actual voltage value to obtain the inverted AC voltage includes:

[0027] Subtracting the actual voltage value from the preset voltage peak value to obtain a voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic;

[0028] The actual voltage value is multiplied by the fundamental wave and added with the harmonic amplitude multiplied by the odd harmonic to obtain an AC voltage reference of the inverter AC power;

[0029] The AC voltage reference and the voltage PI loop are used to calculate to obtain the inverter AC voltage.

[0030] In a third aspect, this embodiment provides a computer-readable storage medium on which a computer program that can be run on a processor is stored. When the computer program is executed by the processor, a method for soft compression of a sine wave of an inverter as described in the first aspect is implemented.

[0031] By adopting the above method, the present application first obtains the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output. And by judging whether the actual voltage value is less than the preset voltage peak value, it is determined whether a soft compression operation is required. Among them, when the actual voltage value is not less than the preset voltage peak value, it indicates that only the conventional inversion operation is performed on the actual voltage value, and the voltage of the obtained alternating current will not be lower than the effective value of the voltage required by the subsequent load. At this time, the actual voltage value is subjected to an inversion process with a reduced amplitude to obtain an inverter AC voltage.

[0032] When the actual voltage value is less than the preset voltage peak value, it indicates that only the actual voltage value is subjected to conventional inversion operation, and the voltage of the AC power obtained will be lower than the effective value of the voltage required by the subsequent load. In order to ensure that the voltage of the AC power finally obtained is not lower than the effective value of the voltage required by the subsequent load, the load can be provided with the required voltage power, and the odd harmonics can be superimposed when the actual voltage value is inverted to obtain the inverted AC voltage. Among them, in order to achieve simpler calculations, the odd harmonics in this embodiment are set to the third harmonics. In this way, when the actual voltage of the high-voltage direct current is less than the preset voltage value, the inverted AC voltage that meets the requirements of the subsequent load can be obtained by superimposing the third harmonic on the sine wave for compression, avoiding the occurrence of insufficient voltage value, and better providing power for the load. Therefore, no matter whether the voltage of the DC power on the DC bus is too large or too small, there is no need to introduce any new equipment, and the required inverted voltage can be obtained by adjusting the amount of calculation with low calculation, so as to achieve smooth output of AC voltage that meets the requirement of no reduction in effective value through simple calculation at all times in embedded occasions. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the AC voltage obtained when the bus DC voltage provided in the present application is reduced without performing a compression operation.

[0034] Figure 2 It is a schematic diagram of the AC voltage obtained by performing a hard compression operation when the bus DC voltage provided in the present application is reduced.

[0035] Figure 3 This is a block diagram of an inverter sine wave soft compression method provided in an embodiment of the present application.

[0036] Figure 4 It is a block diagram of an embodiment of the present application for superimposing odd harmonics when inverting an actual voltage value to obtain an inverter AC voltage.

[0037] Figure 5 This is a schematic diagram of the AC voltage obtained by a sine wave soft compression method for an inverter provided in the present application.

[0038] Figure 6 It is a schematic diagram of the working process of an inverter sine wave soft compression method provided in an embodiment of the present application.

[0039] Figure 7 This is a framework diagram of an inverter sinusoidal wave soft compression system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. However, it should be understood by those of ordinary skill in the art that the present application can be implemented without these details. For those of ordinary skill in the art, it is obvious that various changes can be made to the embodiments disclosed in the present application, and without departing from the principles and scope of the present application, the general principles defined in the present application can be applied to other embodiments and application scenarios. Therefore, the present application is not limited to the embodiments shown, but conforms to the broadest scope consistent with the scope claimed for protection in the present application.

[0041] The embodiments of the present application are further described in detail below in conjunction with the drawings in the specification.

[0042] For ordinary inverters, if the final output AC voltage needs to reach 220V, the DC bus voltage after the inverter front-stage DC-DC processing must be greater than 220×1.414=311V. When the DC bus voltage after the inverter front-stage DC-DC processing is reduced, if the compression operation is not performed during the inverter back-stage DC-AC working process, the AC voltage output by the inverter will be reduced accordingly. Among them, AC output voltage = DC bus voltage / 1.414.

[0043] Figure 1 Schematic diagram of the AC voltage obtained when the busbar DC voltage is reduced without compression operation provided in this application. Figure 1 As shown, when the DC bus voltage is 290V, the AC voltage is not compressed, so the output AC voltage is about 205V, which does not meet the 220V voltage requirement.

[0044] Figure 2 Schematic diagram of AC voltage obtained by hard compression operation when the busbar DC voltage is reduced provided in this application. Figure 2 As shown, when the DC bus voltage is 290V, hard compression will cause the sine wave corresponding to the obtained AC voltage to be directly clipped at a value greater than 290V, resulting in obvious clipping and distortion of the waveform. The output AC voltage is approximately 215.4V, which is less than the effective value of the desired inverter AC voltage of 220V.

[0045] Figure 3 1 is a block diagram of a method for soft compression of a sine wave of an inverter provided in an embodiment of the present application. Figure 3 As shown, a method for inverter sine wave soft compression includes the following steps:

[0046] Step S100, obtaining the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output, and determining whether the actual voltage value is less than the preset voltage peak value. If not, performing an inversion process on the actual voltage value to obtain an inverter alternating current voltage.

[0047] Wherein, obtaining the actual voltage value of the high-voltage direct current includes: determining whether a PWM cycle interrupt signal is obtained, and if so, obtaining the voltage value on the DC bus to obtain the actual voltage value of the high-voltage direct current.

[0048] The present application describes the inverter sine wave soft compression method from the perspective of the inverter. The inverter uses PWM when working. At the end of the PWM cycle, a PWM cycle interrupt signal is generated. The inverter can determine whether the PWM cycle interrupt signal is obtained by checking the signal generated by itself. If there is a PWM cycle interrupt signal in the signal generated by itself, it means that the PWM cycle interrupt signal is obtained. At this time, the voltage value on the DC bus can be obtained by reading the voltage value output by the previous DC-DC, thereby obtaining the actual voltage value of the high-voltage direct current. In this way, the inverter can obtain an actual voltage value every PWM cycle without the need to introduce other additional equipment, thereby achieving low-cost and timely acquisition of the actual voltage value of the high-voltage direct current.

[0049] The above-mentioned preset voltage peak refers to the peak value of the voltage that the inverter needs to output the AC power at the end. The preset voltage peak can be determined by the staff according to the load conditions that are actually required to be driven. After the preset voltage peak is determined by the staff, it is stored in the inverter by the staff.

[0050] Since only when the actual voltage value is less than the preset voltage peak value, the problem of ensuring that the effective value of the inverter AC voltage finally output by the inverter will not be reduced based on the original setting by performing sine wave compression work, and providing a stable voltage for the load that the inverter needs to connect. Among them, the difference between the actual voltage value and the preset voltage peak value can be obtained, and when the difference is less than zero, it is determined that the actual voltage value is less than the preset voltage peak value. When the difference is not less than zero, it is determined that the actual voltage value is not less than the preset voltage peak value. It is also possible to obtain a ratio by dividing the actual voltage value by the preset voltage peak value, and when the ratio is less than one, it is determined that the actual voltage value is less than the preset voltage peak value. When the ratio is not less than one, it is determined that the actual voltage value is not less than the preset voltage peak value.

[0051] AC voltage peak = DC bus voltage / 1.414, AC voltage effective value = AC voltage peak / 1.414. When the actual voltage value is not less than the preset voltage peak value, it indicates that only the actual voltage value is subjected to conventional inversion operation, and the voltage of the AC power obtained will not be lower than the effective value of the voltage required by the subsequent load. In order to enable the inverter to output the voltage value required by the connected load and not provide an excessively high voltage to the load, the actual voltage value obtained by the previous stage DC-DC can also be subjected to an inversion process with a reduced amplitude to obtain an inverted AC voltage. Among them, the inversion process of the actual voltage value with a reduced amplitude to obtain an inverted AC voltage includes the following steps:

[0052] Step S101, dividing a preset voltage peak value by an actual voltage value to obtain an amplitude gain coefficient.

[0053] Step S102, multiplying the actual voltage value by the fundamental wave and the amplitude gain coefficient to obtain an AC voltage reference for the inverter AC power.

[0054] Step S103, using the AC voltage reference and the voltage PI loop to calculate to obtain the inverter AC voltage.

[0055] When the actual voltage value is not less than the preset voltage peak value, substitute the preset voltage value and the actual voltage value into the formula: AC voltage reference = actual voltage value × fundamental wave × preset voltage peak value ÷ actual voltage value to obtain the AC voltage reference of the inverter AC power, where the fundamental wave is a sine wave with an amplitude of 1. For example, if the actual voltage value is 330V and the preset voltage peak value is 311V, then the amplitude gain coefficient = 311÷330, and the AC voltage reference = 330×sin(ωt)×311÷330.

[0056] The obtained AC voltage reference is then sent to the voltage PI loop, so that the inverter AC voltage within this PWM cycle is obtained through calculation of the voltage PI loop. Among them, the voltage PI loop is a function carried by the inverter itself and belongs to the prior art, so it will not be repeated here. In this way, in any case where the actual voltage value of the high-voltage direct current is not less than the preset voltage value, there is no need to compress the sine wave, and the inverter AC voltage that meets the subsequent load requirements can be obtained, so as to better provide power for the load.

[0057] Step S200: If the actual voltage value is less than the preset voltage peak value, odd harmonics are superimposed when the actual voltage value is inverted to obtain an inverter AC voltage.

[0058] When the actual voltage value is less than the preset voltage peak value, it indicates that only the actual voltage value is subjected to conventional inversion operation, and the voltage of the AC power obtained will be lower than the effective value of the voltage required by the subsequent load. In order to ensure that the voltage of the AC power finally obtained is not lower than the effective value of the voltage required by the subsequent load, the load can be provided with the required voltage. When the actual voltage value is subjected to inversion processing, odd harmonics can be superimposed to obtain an inverted AC voltage. In order to achieve simpler calculation, the odd harmonics in this embodiment are set to third harmonics. Figure 4 The embodiment of the present application provides a block diagram of superimposing odd harmonics when inverting the actual voltage value to obtain an inverter AC voltage. Figure 4 As shown, when performing inversion processing on the actual voltage value, superimposing odd harmonics to obtain an inverted AC voltage includes the following steps:

[0059] Step S201 : subtracting the actual voltage value from the preset voltage peak value to obtain a voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic.

[0060] Step S202, multiplying the actual voltage value by the fundamental wave and adding the harmonic amplitude multiplied by the odd harmonics to obtain an AC voltage reference for the inverter AC power.

[0061] Step S203, using the AC voltage reference and the voltage PI loop to calculate to obtain the inverter AC voltage.

[0062] When the actual voltage value of the high-voltage direct current is less than the preset voltage peak value, the AC voltage reference of the inverter AC power is obtained by substituting the preset voltage value and the actual voltage value into the formula: AC voltage reference = actual voltage value × fundamental wave + (preset voltage peak value - actual voltage value) × third harmonic, where the fundamental wave is a sine wave with an amplitude of 1. For example, if the actual voltage value is 300V and the preset voltage peak value is 311V, then the harmonic amplitude = 311-300 = 11, and the AC voltage reference = 300×sin(ωt)+(311-300)×sin(3ωt).

[0063] The obtained AC voltage reference is then sent to the voltage PI loop, so that the inverter AC voltage within this PWM cycle is obtained through calculation of the voltage PI loop. Among them, the voltage PI loop is a function carried by the inverter itself and belongs to the prior art, so it will not be repeated here. In this way, when the actual voltage of the high-voltage direct current is less than the preset voltage value, the inverter AC voltage that meets the subsequent load requirements can be obtained by superimposing the third harmonic on the sine wave for compression, avoiding the occurrence of insufficient voltage value and better providing power to the load.

[0064] Figure 5 Schematic diagram of AC voltage obtained by a method for soft compression of sine wave of an inverter provided in this application. Figure 5As shown, when the DC bus voltage is 290V, the inverter sine wave soft compression method disclosed in this application is performed, which makes the waveform of the sine wave corresponding to the AC voltage smoother without clipping, and the AC voltage reference finally obtained is 220.4V, which meets the voltage requirement of the load. Therefore, in embedded occasions, a smooth AC voltage with no reduction in effective value can be output at all times through simple calculation.

[0065] In order to enable the inverter sine wave soft compression method disclosed in the present application to better output a smooth AC voltage that does not reduce the effective value through simple calculations at all times in embedded occasions, the actual voltage value is further limited to not be lower than a preset reference voltage value. The preset reference voltage value is a parameter set by the staff based on work experience. In this embodiment, the preset reference voltage value is set to 250V.

[0066] In addition, no matter the actual voltage value is not less than the preset voltage peak value, or the actual voltage value is less than the preset voltage peak value, an interruption end signal is generated after the inverter AC voltage is obtained to end the PWM cycle interruption, thereby entering the next PWM cycle, continuing the subsequent work, and repeating the above work after the PWM cycle ends.

[0067] Figure 6 FIG. 1 is a schematic diagram of the workflow of a method for softly compressing a sine wave of an inverter provided in an embodiment of the present application. Figure 6 As shown, first, the soft compression method is started when the PWM cycle is interrupted. Then, the voltage on the high-voltage DC bus is collected, that is, the actual voltage value is collected. Then, it is determined whether the actual voltage value is less than the preset voltage peak value. When the actual voltage value is not less than the preset voltage peak value, the formula: AC voltage reference = actual voltage value × fundamental wave × preset voltage peak value ÷ actual voltage value is used to obtain the soft-compressed AC voltage reference. When the actual voltage value is less than the preset voltage peak value, the formula: AC voltage reference = actual voltage value × fundamental wave + (preset voltage peak value - actual voltage value) × third harmonic is used to obtain the soft-compressed AC voltage reference. Immediately after obtaining the soft-compressed AC voltage reference, the actual inverter voltage, that is, the inverter AC voltage, is obtained through the output voltage PI loop calculation. Finally, after obtaining the inverter AC voltage, the PWM cycle interruption is terminated, thereby completing the soft compression work of this cycle, so that no matter whether the DC voltage on the DC bus is too large or too small, no new equipment needs to be introduced, and the required inverter voltage is obtained by low calculation adjustment, so that the AC voltage that is smooth and does not reduce the effective value can be output by simple calculation at all times in embedded occasions.

[0068] Figure 7 1 is a framework diagram of an inverter sine wave soft compression system provided in an embodiment of the present application. Figure 7As shown, an inverter sine wave soft compression system includes: an acquisition module, a judgment module and a processing module.

[0069] Among them, the acquisition module is used to obtain the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output. The judgment module is used to judge whether the actual voltage value is less than the preset voltage peak value; the processing module is used to, if not less than, perform an inversion process on the actual voltage value with a reduced amplitude to obtain an inverter alternating voltage; if less than, superimpose odd harmonics when performing the inversion process on the actual voltage value to obtain an inverter alternating voltage.

[0070] In addition, odd harmonics are third harmonics. When the actual voltage value is inverted, the odd harmonics are superimposed to obtain the inverter AC voltage, including: subtracting the actual voltage value from the preset voltage value to obtain the voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic; multiplying the actual voltage value by the fundamental wave and adding the harmonic amplitude multiplied by the odd harmonic to obtain the AC voltage reference of the inverter AC; using the AC voltage reference and the voltage IP loop to calculate to obtain the inverter AC voltage.

[0071] The other functions performed by the acquisition module, the judgment module and the processing module as well as the technical details of each function are the same as or similar to the corresponding features in the inverter sine wave soft compression method described above, so they are not repeated here.

[0072] An embodiment of the present application also provides a computer storage medium on which a computer program is stored. When the computer program is run on a computer, the computer can execute the steps of the inverter sine wave soft compression method described above.

[0073] It should be understood that, although the steps in the flowchart of the accompanying drawings are shown in sequence according to the instructions of the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless explicitly stated herein, the execution of these steps is not strictly limited in order and can be performed in other orders.

[0074] The above description is only a partial implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for soft compression of a sine wave of an inverter, characterized in that: include: Get the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output. Determine whether the actual voltage value is less than the preset voltage peak value, When the actual voltage value is not less than the preset voltage peak value, the actual voltage value is subjected to an inversion process with a reduced amplitude to obtain an inverted AC voltage; When the actual voltage value is less than the preset voltage peak value, odd harmonics are superimposed when the actual voltage value is inverted to obtain an inverter AC voltage; The odd harmonic is the third harmonic; When performing inversion processing on the actual voltage value, superimposing odd harmonics to obtain an inverted AC voltage includes: Subtracting the actual voltage value from the preset voltage peak value to obtain a voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic; The actual voltage value is multiplied by the fundamental wave and added with the harmonic amplitude multiplied by the odd harmonic to obtain an AC voltage reference of the inverter AC power, wherein the AC voltage reference=actual voltage value×fundamental wave+(preset voltage peak value-actual voltage value)×third harmonic, and the fundamental wave is a sine wave with an amplitude of one; Using the AC voltage reference and the voltage PI loop calculation to obtain an inverter AC voltage; Wherein, the actual voltage value is not lower than a preset reference voltage value; Performing an inversion process of reducing the amplitude of the actual voltage value to obtain an inverted AC voltage includes: Dividing the preset voltage peak value by the actual voltage value to obtain an amplitude gain coefficient; The actual voltage value is multiplied by the fundamental wave and the amplitude gain coefficient to obtain an AC voltage reference of the inverter AC power, wherein AC voltage reference=actual voltage value×fundamental wave×preset voltage peak value / actual voltage value; The AC voltage reference and the voltage PI loop are used to calculate to obtain the inverter AC voltage.

2. The method according to claim 1, characterized in that The obtaining of the actual voltage value of the high voltage direct current comprises: Determine whether the PWM cycle interrupt signal is obtained. When the PWM period interrupt signal is obtained, the voltage value on the DC bus is obtained to obtain the actual voltage value of the high-voltage DC power.

3. The method according to claim 2, characterized in that After the inverter AC voltage is obtained, an interruption end signal is also generated to end the PWM cycle interruption.

4. An inverter sine wave soft compression system, characterized in that: The system comprises: an acquisition module, a judgment module and a processing module; The acquisition module is used to acquire the actual voltage value of the high-voltage direct current and the preset voltage peak value of the inverter alternating current to be output; The judging module is used to judge whether the actual voltage value is less than the preset voltage peak value; The processing module is used for performing an inversion process of reducing the amplitude of the actual voltage value to obtain an inverted AC voltage when the actual voltage value is not less than the preset voltage peak value; The processing module is used for superimposing odd harmonics when performing inversion processing on the actual voltage value to obtain an inverted AC voltage when the actual voltage value is less than the preset voltage peak value; The odd harmonic is the third harmonic, When performing inversion processing on the actual voltage value, superimposing odd harmonics to obtain an inverted AC voltage includes: Subtracting the actual voltage value from the preset voltage peak value to obtain a voltage difference, and using the voltage difference as the harmonic amplitude of the odd harmonic; The actual voltage value is multiplied by the fundamental wave and added with the harmonic amplitude multiplied by the odd harmonic to obtain an AC voltage reference of the inverter AC power, wherein the AC voltage reference=actual voltage value×fundamental wave+(preset voltage peak value-actual voltage value)×third harmonic, and the fundamental wave is a sine wave with an amplitude of one; Using the AC voltage reference and the voltage PI loop calculation to obtain an inverter AC voltage; Wherein, the actual voltage value is not lower than a preset reference voltage value; Performing an inversion process of reducing the amplitude of the actual voltage value to obtain an inverted AC voltage includes: Dividing the preset voltage peak value by the actual voltage value to obtain an amplitude gain coefficient; The actual voltage value is multiplied by the fundamental wave and the amplitude gain coefficient to obtain an AC voltage reference of the inverter AC power, wherein AC voltage reference=actual voltage value×fundamental wave×preset voltage peak value / actual voltage value; The AC voltage reference and the voltage PI loop are used to calculate to obtain the inverter AC voltage.

5. A computer-readable storage medium having stored thereon a computer program that can be run on a processor, characterized in that: When the computer program is executed by the processor, the inverter sine wave soft compression method according to any one of claims 1 to 3 is implemented.

Images