CN110292064A - A kind of variable electric field generating device and refrigerator - Google Patents

Abstract

The invention discloses a variable electric field generating device and a refrigerator. By adding a variable voltage and frequency conversion circuit in the variable electric field generating device, the alternating current voltage is boosted by an upgrading circuit and passed through a rectifying circuit, and the alternating current input through the rectifying circuit The variable voltage and frequency circuit, the variable voltage and frequency circuit will process the input alternating current according to the temperature of the corresponding refrigerator storage room, so that the frequency and voltage of the AC point after the variable voltage and frequency conversion are the most fresh-keeping items in the storage room. Optimum frequency and voltage, thereby improving the freshness preservation effect of the refrigerator.

Description

A variable electric field generator and refrigerator

technical field

The invention relates to the technical field of refrigerators, in particular to a variable electric field generator and a refrigerator.

Background technique

The current fresh-keeping technologies all focus on appearance rather than internal quality, and rarely involve the internal aging control of fruits and vegetables. However, as a part of human food, fruits and vegetables not only satisfy the sensory experience, but also bring nutrition to people and improve health. Therefore, maintaining their inherent quality through fresh-keeping technology is an important task in the fresh-keeping industry.

In order to keep the quality and freshness of the items in the refrigerator, the existing refrigerators generally adopt fixed frequency and electric field strength, and the storage temperature of each storage area in the refrigerator is different, for example, the food in the freezing area (about -20 ℃), the food in the variable temperature area (-3 ℃) and food in the refrigerated area (5 ℃), etc., which makes it impossible for the fixed frequency and electric field strength to keep all items in the refrigerator fresh.

Contents of the invention

In view of the deficiencies of the prior art above, the object of the present invention is to provide a variable electric field generator and a refrigerator to solve the problem that it is difficult for existing refrigerators to control the destructive effects of excessive free radicals generated inside fruits and vegetables.

The technical scheme adopted in the present invention is:

A variable electric field generating device is characterized in that it includes: a boost circuit, a step-down filter circuit and a rectifier circuit connected to the boost circuit respectively, an anion generator connected to the step-down filter circuit device, at least one variable voltage and frequency circuit connected to the rectifier circuit, and an electrode plate connected to the variable voltage and frequency circuit; the input end of the boost circuit is connected to the current for providing alternating current, and the negative ion The generator is connected between the rectification circuit and the variable voltage and frequency conversion circuit, and both the negative ion generator and the step-down filter circuit are connected to the ground wire.

The variable electric field generating device, wherein, the variable voltage and frequency circuits are 3 circuits, and the 3 circuits of variable voltage and frequency circuits are connected in parallel, and are respectively connected to the electrode plates of the refrigerating room, the electrode plates of the variable room and the electrode plates of the freezing room.

The variable electric field generating device, wherein the frequency range of the alternating current output by the variable voltage and frequency conversion circuit connected to the electrode plate of the freezing chamber is 700-1000HZ, and the voltage range of the alternating current is 3000-8000v.

The variable electric field generating device, wherein the frequency range of the alternating current output by the variable voltage and frequency conversion circuit connected to the electrode plate of the variable greenhouse is 300-700hz, and the voltage range of the alternating current is 1500-3000v.

In the variable electric field generating device, the frequency range of the alternating current output by the variable voltage and frequency conversion circuit connected to the electrode plate of the refrigerator compartment is 0-300hz, and the voltage range of the alternating current is 800-1500v.

The variable electric field generating device, wherein, the variable voltage and frequency conversion circuit can be a two-level direct high-voltage inverter in series with power devices, a three-level voltage source inverter using IGCT and HV-IGBT, and a VFD using LV-IGBT One of the unit series multi-level voltage source inverters.

In the variable electric field generating device, the rectification circuit includes one of a full-wave rectification module, a negative half-wave rectification module, or a positive half-wave rectification module, or any combination thereof.

The variable electric field generating device, wherein the step-down filter circuit includes a step-down unit and a filter unit connected in sequence, the step-down unit is a step-down chip for realizing a step-down function, and the filter unit is a step-down chip for realizing a filter function filter chip.

The variable electric field generating device, wherein, the negative ion generator discharges the ground electrode to generate plasma active substances.

A variable electric field fresh-keeping refrigerator, which includes a refrigerator body, and a variable electric field generating device with a fresh-keeping function as described above, and the variable electric field generating device is installed in the refrigerator body.

Compared with the prior art: this application adds a variable voltage and frequency conversion circuit in the variable electric field generator, and the AC voltage is boosted by an upgrade circuit and passed through a rectification circuit, and the AC input through the rectification circuit is input into a voltage conversion and frequency conversion circuit. The voltage and frequency conversion circuit will perform voltage and frequency conversion processing on the input AC according to the temperature of the corresponding refrigerator storage room, so that the frequency and voltage of the AC point after voltage conversion and frequency conversion are the optimal frequency and voltage for keeping items fresh in the storage room, thereby Improve the fresh-keeping effect of the refrigerator.

Description of drawings

FIG. 1 is a functional block diagram of a preferred embodiment of a variable electric field generating device of the present invention.

Fig. 2 is a circuit diagram of a preferred embodiment of the boost circuit provided by the present invention.

Fig. 3 is a circuit diagram of a preferred embodiment of the rectification circuit provided by the present invention.

Fig. 4 is a circuit diagram of a preferred embodiment of the high-voltage electrode provided by the present invention.

Fig. 5 is a structural diagram of the refrigerator provided by the present invention.

Detailed ways

The present invention provides a variable electric field generating device and a refrigerator. In order to make the purpose, technical solution and effect of the present invention clearer and clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

It should be noted that when a component is referred to as being “fixed on” or “disposed on” another component, it may be directly on the other component or indirectly on the other component. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

It should also be noted that the same or similar symbols in the drawings of the embodiments of the present invention correspond to the same or similar components; The orientation or positional relationship indicated by "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific Orientation, construction and operation in a specific orientation, therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes, and should not be understood as limitations on this patent. For those of ordinary skill in the art, the Understand the specific meaning of the above terms.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

A variable electric field generator provided by an embodiment of the present invention, as shown in FIG. At least one voltage and frequency conversion circuit 205 and the number of electrode plates corresponding to the voltage and frequency conversion circuit 205 . The power supply input terminal of the booster circuit 201 is connected to the power supply providing AC voltage, an output terminal of the booster circuit 201 is connected to the input terminal of the rectification circuit 203, and the output terminal of the rectification circuit 203 is connected to the input terminals of the variable voltage and frequency conversion circuits 205 , the input terminals of each variable voltage and frequency conversion circuit are connected with electrode plates. Another output end of the boost circuit 201 is connected to the input end of the step-down filter circuit 202, and the output end of the step-down filter device is provided with two branches, and one branch is connected to the input end of the negative ion generator 204 , the other branch is connected to the ground wire; the output end of the negative ion generator 204 is connected to the input ends of the variable voltage and frequency conversion circuits 205 .

In this implementation, the AC power provided by the power supply is input to the boost circuit 201, and the input AC power is boosted through the boost circuit 201, and the boosted AC power is transmitted to the step-down filter circuit 202 all the way. The filter circuit 202 filters the boosted alternating current, and the filtered alternating current passes through the negative ion generator 204, so that the negative ion generator 204 produces plasma active substances, and the alternating current after passing through the negative ion generator 204 enters various voltage and frequency conversion circuits 205, The boosted AC point is transmitted to the rectifier circuit 203 in another way, and the boosted AC power is rectified by the rectifier circuit 203, and the rectified AC is merged with the AC power passing through the negative ion generator 204 and then enters various voltage and frequency conversion circuits 205: Each variable voltage and frequency conversion circuit 205 converts the voltage and frequency of the alternating current flowing into it, and transmits the alternating current after variable voltage and frequency to its corresponding electrode plate, so as to excite a variable electric field through the electrode plate. In this embodiment, the voltage and frequency conversion circuit 205 acts on the electrode plate, so that the two electrodes of the electrode plate will vibrate to generate an energy field, and the enzyme activity of the antioxidant enzyme in the stored food can be enhanced under the action of the energy field, and further Remove excessive free radicals and other harmful substances produced by the metabolism of organisms, thereby effectively extending the freshness period of food. In addition, the plasma active substances are generated by connecting to the negative ion generator 204 to discharge, and further kill the surface body on the basis of food preservation. bacteria virus.

Further, since different foods require different energy field strengths, for example, fruits and vegetables, in the environment of the appropriate energy field, the free radical scavenging system in the body (including various antioxidants such as SOD, POD, and CAT) The activity of enzymes) has been enhanced, and the production and removal of free radicals have returned to balance, which shows that the freshness period of fruits and vegetables has been extended; but if it is frozen meat, a stronger energy field is required. In the energy field of frozen meat, the ice crystals formed inside the frozen meat are smaller and rounder, so the tissue cells of the meat are less damaged by ice crystals, the blood water after thawing is less, and the nutrition is maintained better. Therefore, in this embodiment, the variable electric field generating device includes a 3-way variable voltage and frequency conversion circuit 205, and the 3-way variable voltage and frequency conversion circuit 205 is divided into a refrigerating chamber variable voltage and frequency conversion circuit, a variable temperature room variable voltage and frequency conversion circuit and Freezing chamber voltage and frequency conversion circuit; said 3-way voltage and frequency conversion circuit 205 are connected in parallel, and the input terminals of said 3-way voltage and frequency conversion circuit 205 are all connected with said rectifier circuit 203 at said anion generator 204, that is, said After the negative ion generator 204 is merged with the rectifier circuit 203, three parallel branches are arranged, and the three parallel branches are respectively used to connect the variable voltage and frequency circuit of the refrigerator room, the variable voltage and frequency circuit of the variable temperature room and the variable voltage and frequency circuit of the freezer. circuit. In addition, the electrode plates correspond to three groups, which are the electrode plates 208 for the refrigerating room, the electrode plates 206 for the variable temperature room, and the electrode plates 207 for the freezing room; the electrode plates 208 for the refrigerating room are connected to the variable voltage and frequency conversion circuit , the variable temperature room electrode plate is connected with the variable temperature variable frequency circuit of the variable temperature room, and the freezing room electrode plate is connected with the variable voltage frequency conversion circuit of the freezing room, so that the 3-way variable voltage frequency conversion circuit 205 can make The electric field frequencies and electric field strengths of the electric fields generated in the refrigerating room, the variable room and the freezing room are different, so that the food in each storage room is under the optimal electric field strength and electric field frequency, thereby improving the freshness of the food. In addition, in practical applications, any one of the three voltage and frequency conversion circuits 205 can be a two-level direct high-voltage converter in series with power devices, and a three-level voltage source using IGCT and HV-IGBT A frequency converter and one of unit series multilevel voltage source frequency converters using LV-IGBT.

Further, in this embodiment, the frequency range of the alternating current output by the variable voltage and frequency conversion circuit 205 connected to the electrode plate of the freezing chamber is 700-1000 Hz, and the voltage range of the alternating current is 0-8000 V. In this way, on the one hand, it can change the combination mode of water molecules, which can make the ice crystals formed by frozen food smaller and rounder, and it is not easy to form sharp ice crystals in one direction, so as to avoid the formation of sharp ice crystals that damage the cell structure. Frozen, frozen food accelerates through the ice crystal belt, so as to ensure that the food cell tissue is not destroyed, reduce the loss of blood and water weight and the loss of nutrients, and help to keep the food fresh.

Further, the frequency range of the alternating current output by the variable voltage and frequency conversion circuit 205 connected to the electrode plates of the variable temperature chamber is -700hz, and the voltage range of the alternating current is 1500-0v. The electric field generated in this way acts on the food in the variable temperature range of -5-0°C, which can realize the non-freezing and refrigeration of meat and seafood below the freezing point, and can be processed out of the warehouse at any time, while effectively preventing discoloration.

Further, the frequency range of the alternating current outputted by the voltage and frequency conversion circuit 205 connected to the electrode plate of the refrigerator compartment is 0-hz, and the voltage range of the alternating current is 800-1500v. In this way, a specific frequency range is used for the fruits and vegetables in the refrigerator. The electric field generated by such alternating current can directly generate an alternating electric field on the liquid water molecules, change the hydrogen bond structure between water molecules, and improve the freshness of fruits and vegetables.

Further, in an implementation manner of this embodiment, as shown in FIG. 2 , the boost circuit 201 includes a rectification unit 2011 and a boost unit 2012 connected in sequence. The rectification unit 2011 is used to isolate and rectify the AC voltage input by the power supply; the boost unit 2012 is used to boost the AC voltage that has been isolated, bucked and rectified; the boost unit 2012 is also connected with The step-down filter circuit 202 is connected to the rectification circuit 203 . The input 220V AC voltage is isolated and stepped down by the rectification unit 2011, and rectified to obtain a stable AC voltage to the booster unit 2012, and the booster unit 2012 boosts the voltage as needed to meet the high voltage demand for energy field generation.

Further, as shown in FIG. 2 , the rectification unit 2011 includes a switch S, a fuse FU, an isolation power transformer T1 and a rectification bridge VD. One end of the switch S is connected to a 220V power supply, one end of the fuse FU is connected to the other end of the switch S, the other end of the fuse FU is connected to an isolation power transformer T1, and the input end of the isolation power transformer T1 is also connected to the power supply The output terminal of the isolated power transformer T1 is connected to the rectifier bridge VD, and the output terminal of the rectifier bridge VD is connected to the boost unit 2012 .

The boost unit 2012 includes a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a potentiometer RP, a first thyristor VT, a Zener diode VS and a boost transformer T2 . The input end of the first capacitor C1 and one end of the first resistor R1 are connected to the output end of the rectifier bridge VD, and the other end of the first resistor R1 is connected to one end of the second resistor R2 and the input end of the second capacitor C2 , the other end of the second resistor R2 is connected to the output end of the Zener diode VS, the input end of the Zener diode VS is connected to the potentiometer RP, and the potentiometer RP is also connected to the first thyristor VT and the third thyristor VT. The resistor R3 is connected, the first thyristor VT is also connected to one end of the second resistor R2, the output end of the second capacitor C2 is connected to the input end of the step-up transformer T2, and the output end of the step-up transformer T2 is connected to the rectifier The circuit 203 is connected, and the first capacitor C1, the third resistor R3, the first thyristor VT and the step-up transformer T2 are all grounded.

In particular, in the embodiment of the present invention, since the optimal field strength of the high-voltage electric field required by different foods to be stored is different, optimal configuration can be performed according to the actual food to be stored, and an appropriate boost voltage can be selected to obtain a better electric field strength , the higher the voltage value of the boosted AC power supply, the greater the field strength of the high-voltage electric field output by the rectifier device.

Optionally, the booster circuit 201 can be a coil-type booster circuit 201 or an electronic booster circuit 201, and the outer side is set as a lightweight metal casing, such as an aluminum casing, which has good heat dissipation performance and has little effect on the overall weight , the surface is hard oxidized, the friction resistance is good, and it can resist the extrusion or impact of a certain external force. The safety voltage is 8V-36V, which is lower than the voltage that is harmful to the human body. It has high safety. The predetermined range of high voltage It is 1000-8000V, and the high voltage can be selected in a wide range, and the appropriate voltage can be selected according to the needs to generate an energy field of corresponding strength.

It should be noted that, in the embodiment of the present invention, in addition to the coil boost circuit 201 including a transformer and the electronic boost circuit 201 boosted by a chip, the boost circuit 201 can also use other boost methods , the present invention does not specifically limit this, and all booster circuits 201 that can meet the boosting requirement can be used.

Furthermore, in the embodiment of the present invention, the rectification circuit 203 is one of the full-wave rectification circuit 203, the negative half-wave rectification circuit 203 or the positive half-wave rectification circuit 203 or any combination thereof. Vibration is formed in the space through the rectification circuit, and the alternating electric field is directly generated on the water molecules, changing the hydrogen bond structure between the water molecules. Under the action of the electric field, the water molecules combine with proteins and carbohydrates to form bound water, which protects the proteins. and the efficacy of carbohydrates; at the same time, the activity of water is reduced and the growth of bacteria is inhibited. Preferably, the present invention adopts a full-wave rectification circuit 203, which is realized by a thyristor. In the full-wave rectification circuit 203, two thyristors are used, correspondingly, there are two gate drive circuits, and the boosted AC voltage is rectified by the rectification circuit 203, and then output to the high-voltage electrode to generate an energy field.

Specifically, referring to FIG. 3 , the full-wave rectification circuit 203 includes a second thyristor VT1 , a third thyristor VT2 and a fourth resistor R4 . One end of the second thyristor VT1 and one end of the third thyristor VT2 are respectively connected to the output end of the step-up transformer T2, and the other end of the second thyristor VT1 and the other end of the third thyristor VT2 are interconnected and connected to the fourth resistor R4 One end is connected, and the other end of the fourth resistor R4 is connected with the center tap of the step-up transformer T2.

As shown in Figure 4, in the embodiment of the present invention, the electrode plate includes a conductor layer 301, an insulating layer 302 wrapping the conductor layer 301, and a wire 303 connected to the conductor layer 301, and the wire 303 is also connected to the rectifier circuit 203 Connect with negative ion generator 204. The conductor layer 301 is wrapped by the insulating layer 302 for insulation and isolation to avoid electric shock, and then the lead wire 303 is connected to the rectifier circuit 203 to receive the boosted AC power to realize vibration between the two electrodes of the electrode plate to generate an energy field. In addition, the high-voltage electrode is made of a flexible copper plate with a thickness of 0.01-1mm and good flexibility. It can be installed in the inner liner of the refrigerator or in the middle layer between the inner liner and the outer shell, and can be bent and deformed as needed. The surface is insulated to prevent leakage. occur.

Optionally, the insulating layer 302 can also be set to partially cover the conductor, as long as the insulation isolation during use can be realized; the insulating layer 302 can be directly sealed by heat plastic sealing or cold plastic sealing technology; the conductor layer 301 is not limited to use Flexible copper plates can be made of conductive materials, such as gold, silver, copper, iron, aluminum, graphite, etc.; multiple high-voltage electrodes can be placed in different positions of the refrigerator, such as the back of the refrigerator, variable room and freezer In the foam layer of the plate, in the bottom foam layer, in the top foam layer, etc., the energy field generated between the high-voltage electrode plates interacts, and the energy field is concentrated and strengthened.

Further, the step-down filter circuit 202 includes a step-down unit and a filter unit that are connected in sequence, the step-down unit is a step-down chip that realizes a step-down function, and the filter unit is a filter chip that realizes a filter function. The step-down filter circuit 202 device can effectively reduce the impact of high-voltage current on grounding, filter high-frequency clutter and improve output quality, and at the same time, can greatly enhance the vibration properties of high-voltage electrode output, and can improve the electric field to treat polar molecules inside stored food Direct interaction with enzymes. Specifically, the embodiment of the present invention introduces the excess charge generated by the alternating voltage on the variable electric field generating device 10 into the ground through the step-down filter device, so as to avoid damage to the circuit and components caused by the impact of the excess charge. Since the step-down filtering device and the step-down chip and filter chip therein are all existing technologies, there are many alternative ways, which will not be described in detail here.

In a further embodiment, a negative ion generator 204 is connected between the rectifier circuit 203 and the high-voltage electrode, and the negative ion generator 204 discharges the ground electrode to generate plasma active substances, and further kills the surface on the basis of food preservation. Bacterial virus. For example, in order to prevent the adverse effects caused by the long-term accumulation of positive charges in the space, a negative ion generation circuit is arranged in the above-mentioned electric field space to eliminate the accumulation of positive charges. During the process of eliminating positive charges, it can further sterilize and preserve freshness and prolong the freshness period of fruits and vegetables. Since the negative ion generator 204 is very common in the market, its circuit structure is well known to those skilled in the art, and will not be repeated here.

Based on the above-mentioned variable electric field generating device, as shown in FIG. The field generating device 10 is installed in the refrigerator body. The refrigerator body includes a refrigerating chamber 21, a freezing chamber 22 and a compressor chamber 23; the variable electric field generating device includes three electrode plates, and the three electrode plates are respectively assembled in the refrigerating chamber 21 and the freezing chamber 22. And compressor room 23, make described refrigerator have fresh-keeping function. By setting the variable electric field generating device 10 in the refrigerator, an energy field is generated between the two electrodes of each electrode plate, and the energy field enhances the enzyme activity of antioxidant enzymes in the organism, and these enzymes further clear the organism Harmful substances such as excessive free radicals produced by metabolism can effectively prolong the freshness period of food, and then connect negative ion generator 204 to generate plasma active substances, and then further kill surface bacteria and viruses on the basis of food preservation.

In summary, in the electric field fresh-keeping refrigerator provided by the present invention, the present invention utilizes the boost circuit 201 to boost the AC voltage such as 220V through the boost circuit 201, passes through the rectifier circuit 203, and outputs each variable voltage and frequency conversion circuit 205, through the described The variable voltage and frequency conversion circuit 205 outputs alternating currents of different voltages to different electrodes, and generates electric fields of different frequencies and different intensities through different alternating currents, so that the refrigerator can generate electric fields for each sub-refrigerating room, variable room room and freezing room, and the cooling room , the frequency and intensity of the electric field in the freezer and variable temperature room can be determined according to the respective set temperatures, so that an electric field is generated in each electrode plate in its corresponding space, and an alternating electric field is directly generated on the water molecules, changing the water molecules. Hydrogen bond structure, under the action of an electric field, water molecules combine with molecules such as proteins and carbohydrates to form bound water, which protects proteins and carbohydrates; at the same time, the activity of water is reduced and the growth of bacteria is inhibited; in addition, variable The electric field generating device can generate an energy field of suitable strength in the refrigerator to enhance the preservation effect of cold storage, soft freezing and frozen food, and generate plasma active substances through the discharge of the negative ion generator 204, and further improve the freshness of food on the basis of food preservation. Kill surface bacteria and viruses. The booster circuit 201 used in the present invention has good physical properties, adopts a light metal shell, has good heat dissipation performance, and has little effect on the overall weight, has a hard oxidation treatment on the surface, has good friction resistance, and can resist extrusion or bumping by a certain external force. impact; strong adaptability and stability with load.

It should be understood that the application of the present invention is not limited to the above examples, and those skilled in the art can make improvements or transformations according to the above descriptions, and all these improvements and transformations should belong to the protection scope of the appended claims of the present invention.

Claims (10)

1. a kind of variable electric field generating device, characterized in that it comprises: booster circuit is connected with the booster circuit respectively The decompression filter circuit and rectification circuit connect, with it is described decompression filter circuit be connected anion generator, at least all the way with The variable voltage variable frequency circuit of the rectification circuit connection, and the electrode plate with the variable voltage variable frequency circuit connection；The boosting electricity The input terminal on road is connected with the electric current for providing alternating current, and the anion generator is connected to the rectification circuit and institute It states between variable voltage variable frequency circuit, and the anion generator is connect with ground wire with the decompression filter circuit.

2. variable electric field generating device according to claim 1, which is characterized in that the variable voltage variable frequency circuit is 3 tunnels, 3 tunnels Variable voltage variable frequency circuit in parallel, and respectively with refrigerating chamber electrode plate, temperature-changing chamber electrode plate and freezing chamber electrode plate.

3. variable electric field generating device according to claim 2, which is characterized in that the transformation of the freezing chamber electrode plate connection The frequency range of the alternating current of frequency changer circuit output is 700-1000HZ, and the voltage range of alternating current is 3000-8000v.

4. variable electric field generating device according to claim 2, which is characterized in that the transformation of the temperature-changing chamber electrode plate connection The frequency range of the alternating current of frequency changer circuit output is 300-700hz, and the voltage range of alternating current is 1500-3000v.

5. variable electric field generating device according to claim 2, which is characterized in that the transformation of the refrigerating chamber electrode plate connection The frequency range of the alternating current of frequency changer circuit output is 0-300hz, and the voltage range of alternating current is 800-1500v.

6. variable electric field generating device according to claim 1, which is characterized in that the variable voltage variable frequency circuit can be power Two level direct voltage frequency converter of devices in series, using IGCT, HV-IGBT three-level voltage source frequency converter and use LV- One of cells cascaded multilevel voltage source frequency converter of IGBT.

7. variable electric field generating device according to claim 1, which is characterized in that the rectification circuit includes full-wave rectification mould One of block, negative half-wave rectification block or positive half-wave rectification module or any combination thereof.

8. variable electric field generating device according to claim 1, which is characterized in that the decompression filter circuit includes successively connecting The pressure unit and filter unit connect, the pressure unit are the decompression chip for realizing buck functionality, and filter unit is to realize filter The filtering chip of wave energy.

9. variable electric field generating device according to claim 1, which is characterized in that the anion generator discharges to earth polar Generate plasma active object.

10. a kind of variable electric field fresh-keeping refrigerator, which is characterized in that including described in refrigerator body and claim any one of 1-9 Variable electric field generating device with fresh-keeping function, the variable electric field generating device are mounted in the refrigerator body.