107results about How to "Reduce the impact of volatility" patented technology

The present invention relates to a method for replacing cache files comprising the following steps: acquiring the historical access frequency and the current access frequency of the each stored cache file,acquiring the average access frequency of each cache file according to the historical access frequency, the current access frequency, the weight value of the preset historical access frequency, and the weight value of the preset current access frequency, wherein the weight value of the preset historical access frequency is less than the weight value of the preset current access frequency,acquiring the cache file with the smallest average access frequency,and replacing the cache file with the smallest average access frequency by using the new cache file. The method for replacing the cache file can improve the effectiveness of the cache decision. Besides, the present invention also discloses a device for replacing cache files and a network system thereof.

The invention relates to the field of engineering manufacture, in particular to an optimal design method for production line layout. The technical problem that the influence of production fluctuation on production efficiency cannot be reduced by the conventional method so as to reduce enterprise benefits is solved. According to the scheme, the optimal design method for new production line layout mainly comprises the following steps of: acquiring the labor house data of original sub-procedures; generating functional segments and a station number by adopting a line balancing planning method, so that the cycle time of a single line in each functional segment is shortest; when total investment C is determined, finding all N and S combinations consistent with a constraint condition by using an enumeration method; calculating the cycle time of each functional segment; calculating the overall cycle time of each [N, S] scheme; and performing calculation according to the steps, and when the total investment C is determined, determining a scheme with the shortest cycle time in all the [N, S] schemes as a target scheme. The method can be used for the design of the new production line layout and the modification of the conventional production line layout.

To obtain a semiconductor device and a method of manufacturing the same which can reduce influence of fluctuation in characteristic among transistors due to fluctuation in laser light irradiation number and laser light intensity on a semiconductor. There is provided a semiconductor device with plural pixels having transistors forming a matrix pattern, in which: the transistors have semiconductors crystallized by laser light irradiation; the semiconductors stretch over at least two pixels; the length of each of the semiconductors is longer than the pixel pitch of the pixels; and when the scan pitch of the laser light is given as M and the pixel pitch of the pixels is given as N, the semiconductors are irradiated with the laser light N / M times or more.

The invention discloses a minitype F-P reflective index sensor of a full optical fiber ring-type reflecting surface structure, which comprises a general mono-mode optical fiber, a large-core diameter hollow-core optical fiber and an optical fiber with a through hole at the center which are welded and fixed in succession; the large-core diameter hollow-core optical fiber and the optical fiber with the through hole at the center are communicated; the contact surface of the optical fiber with the through hole at the center and the large-core diameter hollow-core optical fiber forms the ring-shaped reflecting surface; the invention has the beneficial technical effects that the invention provides the novel reflective index sensor which is simple to manufacture, small in volume and high in measurement accuracy, and has wide application range and strong capability of resisting disturbance.

A defrosting method for air-cooled heat pump system features that the condensing pressure is controlled by pressure difference control valve and / or condensing pressure regulating valve. Its defrosting device is composed of air heat exchanger, liquid storage unit, pressure controller, and one-way valve.

The invention discloses a ring oscillator. The ring oscillator mainly comprises three differential delay units D1, D2 and D3 connected in series and an injection unit INJ. 180-degree phase shift is realized from the input end of the first delay unit to the output end of the third serial-connection delay unit, the delay time is reduced through feedback of multiple loops, and the oscillation frequency is further improved. Each differential delay unit is provided with a rough tuning circuit and a fine tuning circuit, wherein the rough tuning circuit is used for setting the minimum delay or the maximum delay, and the fine tuning unit is used for adjusting the minimum delay and the maximum delay. Subharmonic signals at the frequency of output signals are injected to a grid electrode of the injection unit, and the shaking performance of the oscillator is improved. The ring oscillator has the rough tuning and fine tuning functions within the wide-frequency range, is low in voltage sensitivity, reduces the influences of bias voltage fluctuation, realizes low-shaking output clock signals and can be applied to a wireless receiver frequency synthesizer or a clock data recovery circuit.

The invention discloses an enzyme immunoassay method for progestational hormone in excrement of sows. The method comprises the steps of: (1) sample collection: collecting the excrement of the sows, weighing and dissolving 0.5 g of excrement of the sows into 20 ml of measuring buffer liquid, carrying out centrifuging, taking and placing supernatant at 4 DEG C to be detected; and (2) measuring content of progestational hormone in a sample by utilizing competitive ELISA (enzyme-linked immuno sorbent assay): measuring according to an ELISA process. According to the enzyme immunoassay method for the progestational hormone in the excrement of the sows, the detection sensitivity of progesterone reaches 0.2 ng / ml or 8 ng / g; the recovery rate of the progesterone is 95.78%; inter-assay and intra-assay variable coefficients are respectively 6.8% (n is equal to 9) and 11.23% (n is equal to 8); the specificity of the progesterone is that the cross reaction rates of the progesterone to estradiol, estriol and oestrone are all less than 0.01%, and the cross reaction rate of the progesterone to testosterone is 0.35%; the stability is good; the required sample is easy to collect, animals are not injured, a measured result is reliable, and a method for measuring blood of the animals can be replaced to monitor a series of reproductive activities of the animals.

The invention discloses a stabilizing circuit of a charge pump output voltage. The stabilizing circuit of the charge pump output voltage comprises two comparison paths, a comparison device and a controller; the two comparison paths are used for providing two input ends of a reference voltage and a detection voltage to the comparison device, the controller controls a charge pump according to a comparison result so as to make the output voltage maintain steady. When the two comparison paths conduct mirroring through an NMOS pipe and make the output voltage steady through two sub-circuits, the image current of the two comparison paths is irrelevant with supply voltage and the two comparison paths have positive temperature coefficients. The output voltage of the charge pump is the superposition of all resistive voltages which have positive temperature coefficients in a second comparison path, and all diode voltages which have negative temperature coefficients and all source-drain voltages of second NMOS pipes which have negative temperature coefficients, the superposition of the positive and negative temperature coefficients can make the temperature coefficients of the output voltage of the charge pump decrease to be approaching zero, and thus the stability of the output voltage of the charge pump can be improved. The stabilizing circuit of the charge pump output voltage can also shorten the time for refreshing the reference voltage and the detection voltage, and thus lowering the power dissipation.

The invention discloses a comprehensive urban distribution network saturated load forecasting method, which can forecast a power grid saturated load value by determining a comprehensive optimal power grid saturated load forecasting model. The determination of the comprehensive optimal power grid saturated load forecasting model can boil down to the solution of the mathematical expectations of optimal and better comprehensive power grid saturated load forecasting models in order to reduce the fluctuation and randomness of the forecast result change law. The solution of the comprehensive optimal power grid saturated load forecasting model can be regarded as a probability optimization problem. The comprehensive urban distribution network saturated load forecasting method has the advantage that the method can realize the organic combination of single forecasting methods and help to reduce the affection of randomness and fluctuation.

The invention discloses a double-end direct current power distribution network protection method, comprising the following steps: using the current variance value to replace the current difference value and serving as the starting threshold to constitute the inverse time current variance protection and reduce the fluctuation impact caused by transition resistance and load changes; using the voltage as an acceleration factor to speed up the removal rate of reverse time over-current protection on near-end fault of a line; and introducing a current differential direction to realize the distinction between the inside area of a faulty line and the outside area of the faulty line so as to accelerate the speed of direction judgment to prevent the protection malfunction. The invention is based on the local measurement quantity, does not need communications, can act quickly, and has certain ability to withstand transition resistance.

The invention discloses a method for projecting traveling wave of a same-tower double-circuit HVDC transmission line. The method includes employing different criteria for and setting the upper and lower layers of pole wires respectively, eliminating outer-zone faults of the upper-layer pole wire through voltage change rate and current direction, eliminating outer-zone faults of the lower-layer pole wire through ground-mode change rate, employing voltage integration ratio to distinguish the fault of the very pole wire, for the upper-layer pole wire, from that of the other pole wire, and employing voltage integration ratio and modulus integration ratio to distinguish the fault of the very pole wire, for the lower-layer pole wire, from that of the other pole wire. The method has the advantage of high sensitivity, less operation burden and short determination time, the information of the very round is needed, communication between different rounds is not required, and influence of transition resistance is minimal. The fault pole wire of a same-tower double-circuit DC transmission line can be rapidly determined, and misjudgement hardly occurs.

The invention discloses a system and a method for producing a fracturing propping agent by taking red mud as a raw material. The system comprises a charging machine, a high temperature furnace, a swing-out device, a blanking bin, a tempering furnace and screening equipment, wherein the high temperature furnace is connected with the blanking bin or the swing-out device; dosing is performed by taking inorganic solid wastes as raw materials; and the product is prepared by performing high-temperature melting in the high temperature furnace and molding in a molding device. The method comprises the following steps: (1) dosing, namely mixing pure red mud or red mud with one or more of fluorite, silica sand, potassium (or sodium) feldspar and dolomite; (2) mixing and performing wet grinding, namely mixing and performing wet grinding on the prepared materials; (3) drying and granulating; (4) melting the granulated materials in the high temperature furnace; (5) molding the granulated materials into propping agent granules by utilizing the molding device; and (6) screening, weighing and packaging the propping agent granules by virtue of the screening equipment. The system and the method are high in product yield, high in production efficiency and low in cost.

The invention provides temperature measuring equipment, a temperature measuring module and a temperature measuring method based on a thermistor. A reference resistor and the thermistor are arranged inseries to supply power, and when the thermistor is at a reference temperature, voltage values at two ends of the reference resistor and voltage values at two ends of the thermistor are measured; whenthe thermistor is at a target temperature, voltage values at two ends of the reference resistor and voltage values at two ends of the thermistor are measured; a specific value expression between a target thermosensitive resistance value and a reference thermosensitive resistance value of the thermistor is deduced, a corresponding position in the expression is described by substituting resistancevalue-temperature characteristics of the thermistor into the expression to obtain a final expression of the target temperature. According to the application, the reference voltage is collected in realtime by utilizing a voltage division principle, so that the influence of voltage source fluctuation is reduced, the actual resistance value of the thermistor does not need to be calculated, an intermediate variable is used for temperature calculation, the influence of reference resistance error is eliminated, and data transmission between equipment is facilitated.

The invention provides a two-time-scale-based user-side energy management method, which can be simultaneously applicable to fluctuation of distributed power generation equipment and demands of power generation, power purchase, power selling, power utilization, energy storage and load regulation of a user, also has low complexity and is easy to operate. A user side comprises the distribution power generation equipment, a load and energy storage equipment, a two-time scale comprises a large time slot and a small time slot, and the large time slot comprises K small time slots. The method comprises the steps of building a total utility function of the user under the large time slot, optimizing load power utilization quantity of the user in the large time slot, service electric quantity and charge-discharge electric quantity of energy storage equipment by taking the optimal total utility function of the user as a target, and regulating the load in the small time slot according to a forecast error of the charge-discharge electric quantity of the energy storage equipment so that the fluctuation of power generation quantity of the distributed power generation equipment is offset, wherein the forecast error is difference between a forecast value and an actual value of the charge-discharge electric quantity of the energy storage equipment in the small time slot.

The invention relates to a desulfurization / vermiculization / inoculation-integrated vermicular cast iron modifier and a preparation technique thereof. The modifier is mainly composed of the following components in percentage by weight: 6-10% of limestone flour, 76-80% of rare-earth magnesium alloy particle, 13-16% of flake high-purity graphite powder and the balance of adhesive. The preparation technique comprises the following steps: by using the limestone flour as the desulfurizer, the rare-earth magnesium alloy as the vermiculizer, the flake high-purity graphite powder as the retarder and inoculator and the water glass as the adhesive, crushing the alloy, carrying out primary mixing and secondary mixing, naturally setting, and drying. The modifier can complete the desulfurization, vermiculization and inoculation operations in one vermicular cast iron production process, and can stably obtain the vermicular cast iron with the vermicular ratio of higher than 85%.

The invention discloses a paver material splitting system for increasing material splitting material level stability and a control method. The control method comprises the following steps: step one, computing a needed material amount delta according to the walking speed V, the paving width B and the paving thickness H of a paver; step two, computing the material splitting rotating speed X1 according to the needed material amount delta as well as the radius R and the thread pitch P of a material splitting blade, and using the material splitting rotating speed X1 as a control reference signal, wherein X1 is equal to delta / (pi*R*R*P); step three, measuring the material level by material level sensors which are arranged at two ends of a material splitting groove, sending the material level toa controller, and generating a control signal X2 according to measured actual material level values of the two ends of the material splitting groove by the controller; step four, outputting a final control signal X to a material splitting hydraulic pump for controlling the material splitting rotating speed of a material splitting motor according to preset control weights K1 and K2, wherein X is equal to K1*X1+K2*X2, K1 is larger than K2 and the sum of K1 and K2 is equal to 1. According to the control method disclosed by the invention, the problems of non-uniform material level and too fast material splitting rotating speed within a length range of a whole material groove can be well solved, and the uniformity of flatness and compactness of a paved pavement can be increased.

The invention provides a microgrid energy storage optimization scheduling method based on a sparrow search algorithm, and the method comprises the steps: 1, carrying out the analysis of all distributed power supplies and storage battery energy storage equipment in a microgrid, collecting a renewable energy power generation power prediction curve, a load prediction curve and a gradient electricity price of each distributed power supply and storage battery energy storage equipment in the microgrid; and step 2, with the lowest cost under the dynamic gradient electricity price as a target, establishing a micro-grid optimization operation target function, determining operation constraint conditions of the micro-grid optimization operation target function, and establishing a micro-grid optimization scheduling model according to the micro-grid optimization operation target function and the operation constraint conditions. According to the method, the total cost of electricity price is reduced by performing optimal scheduling on the energy storage system of the micro-grid, the limitation of the maximum charge and discharge depth of the storage battery is considered, the sparrow search algorithm is combined, stable and safe operation of the micro-grid is realized, and the influence of renewable energy power generation intermittency and volatility in the micro-grid is reduced.

The invention provides a heat accumulation type electric furnace flue gas waste heat recovery system which comprises a perpendicular type connecting flue, a heat accumulation type water-cooling settling chamber, a heat convection waste heat boiler, a feed water heater, a steam heat accumulator and the like. After flue gas inside a combustion settling chamber passes through the perpendicular type connecting flue, the temperature and the flow rate of the flue gas are preliminarily integrated through the heat accumulation type water-cooling settling chamber, and then the flue gas sequentially enters the heat convection waste heat boiler and is exhausted to the atmosphere after the flue gas is cooled through the feed water heater and dust of the flue gas is removed through a dust remover. Raw water is heated through the feed water heater and then enters a deaerator for removing oxygen in the raw water. Then, the raw water flows through the heat convection waste heat boiler and the heat accumulation type water-cooling settling chamber and generates saturated steam to be fed into the steam heat accumulator. The steam enters a superheater after being buffered by the steam heat accumulator, and the superheated steam is output stably in a superheated mode. According to the heat accumulation type electric furnace flue gas waste heat recovery system, due to the fact that the two peak clipping trough levelling measures of the heat accumulation type water-cooling settling chamber and the steam heat accumulator are set, flue gas waste heat, generated by an electric furnace, with unstable fluctuations passes through the heat accumulation type electric furnace flue gas waste heat recovery system so as to stably and efficiently output the superheated steam.

The invention relates to the technical field of storage battery energy storage and quick charging, in particular to a super-capacitance high-energy pulse source based on an embedded microcontroller. The super-capacitance high-energy pulse source aims to solve the problems of power supply fluctuation and harmonic pollution in the charging process of a common pulse source, and remarkably improve the quick charging effect. By the adoption of the technical scheme, the super-capacitance high-energy pulse source comprises an embedded microcontroller main control unit and a super capacitor, the main control unit is respectively connected with a capacitor charging control switch unit and a battery charging control switch unit, a super-capacitance unit is connected between the capacitor charging control switch unit and the battery charging control switch unit, the super capacitor unit is connected with a capacitance balancing circuit, and a charging source is sequentially connected with the capacitor charging control switch unit, the battery charging control switch unit and a battery unit in serial.

The invention discloses a preparation method of a foldable thermochromic device based on a nanowire film. According to the preparation method of the foldable thermochromic device based on the nanowirefilm, when a metal nanowire film is located under a thermochromic display layer on a substrate, the metal nanowire film is prepared by automatic blade coating, and the hermochromic display layer is prepared by silk-screen printing; and when the thermochromic display layer is located under the metal nanowire film on the substrate, the hermochromic display layer is prepared by ink jet printing, andthe metal nanowire film is prepared by spray coating. The metal nanowire film has high optical transmittance, an ultralow resistance value and a high heat conductivity coefficient, has an invisibility function on the substrate, and can be located on the same side of the substrate with a thermochromic display object; and the quantity of heat is transmitted to a thermochromic material directly andrapidly, and the display object is not shielded.

The invention discloses NaLaMgWO6:xSm<3+> red phosphor powder for an LED (Light Emitting Diode), and a preparation method of the NaLaMgWO6:xSm<3+> red phosphor powder, and belongs to the technical field of preparation of luminescent materials. The NaLaMgWO6:xSm<3+> red phosphor powder for the LED is prepared by using NaOH.H2O, WO3, La2O3, MgO and Sm2O3 as raw materials. The method has the advantages that the raw materials are simple and easily obtained, the operation is simple, the preparation period is short, and the method is pollution-free and suitable for large-scale industrial production. The prepared NaLaMgWO6:xSm<3+> red phosphor powder which is tested and analyzed by an XRD, an SEM and a fluorescence spectrophotometer is higher in purity, high in crystallinity, uniform in grain size and high in dispersity, where x is equal to 0.01 to 0.05; the coverage range of an emission wavelength is 550 to 680nm, the color purity of red light exceeds 92 percent, and the correlated color temperature reaches 1392K.

The embodiment of the invention provides a fire rescue positioning method and device, computer equipment and a storage medium. The method comprises the following steps: receiving an alarm request sent by an applet running in an instant messaging tool, wherein the alarm request contains video data collected by the applet and a first position positioned by the applet; identifying an object with an accident in the video data as a target object; calculating a second position of the target object based on the first position in the video data; and converging the plurality of second positions to a building matched with the accident on an electronic map to determine that the accident occurs in the building. According to the fire rescue positioning method provided by the embodiment of the invention, the accurate positioning of the disaster situation and the information sharing of the disaster situation are realized, so that more targeted rescue can be carried out.

The invention discloses a PWM rectifier with consideration of power quality control. The PWM rectifier comprises a central controller, at least one slave controller, and at least one rectifier main circuit. In addition, the controlling method includes: the slave controller introduces power feedward decoupling into a power inner-loop controller based on a grid need to control the rectifier main circuit to carry out reactive compensation and / or harmonic suppression. The PWM rectifier and the controlling method have the following advantages: an energy absorption mode and an energy feedback mode are realized and reactive compensation and / or harmonic suppression can be carried out in the two kinds of modes, so that a primary objective of completing active power transmission of a direct-current side can be achieved; and a power quality problem with common point existence can be solved by fully using the residual capacity of the PWM rectifier and energy storage capacity of the energy storage type load.

The invention relates to the technical field of sensor circuits, in particular to a four-quadrant sensor circuit. The four-quadrant sensor circuit comprises four sub-circuits respectively connected with a four-quadrant sensor. Each sub-circuit comprises an amplifying circuit and a filter circuit, wherein the amplifying circuit is connected with the output end of the four-quadrant sensor, the filter circuit is connected with the output end of the amplifying circuit, and a shunt circuit for noise reduction is connected to the input end of the amplifying circuit. The four-quadrant sensor circuit has the advantages that the shunt circuit for noise reduction is arranged in each sub-circuit of the four-quadrant sensor, the four-quadrant sensor circuit is simple in structure, a good noise reduction effect on signals output by the sensor can be achieved, and system control precision is guaranteed effectively.

The invention relates to a fully automatic evaporation overflow measuring device and belongs to the meteorology and water conservancy technology field. The fully automatic evaporation overflow measuring device comprises an evaporating dish, a water filling barrel, and a measuring barrel connecting the evaporating dish through a pipeline. The measuring barrel has two pairs of water level control switches, wherein an open overflow switch and a closed overflow switch control a drain solenoid valve, and an open water filling switch and a closed water filling switch control a water filling solenoidvalve. A magnetostrictive water level is placed in the measuring barrel to measure a real-time water level in the evaporating dish, and an electromagnetic flowmeter is connected to a right side pipeline of the measuring barrel so as to measure water filling and an overflow flow. A right side of the electromagnetic flowmeter is divided into a water filling pipe and an overflow pipe which are provided with a water filling solenoid valve and the drain solenoid valve, and the measuring barrel is close to a peripheral concrete wall of an evaporation pool. In the invention, fully automatic water filling and draining can be realized, manual operation can be replaced and data is stored automatically in real time.

The invention provides a power supply circuit, which comprises a rectification circuit, a first filtering circuit, a boost-buck circuit and a controller, wherein the input end of the rectification circuit is connected to an alternating current power source to receive alternating current output by the alternating current power source and carry out rectification processing on the alternating current to obtain first direct current; the input end of the first filtering circuit is connected to the output end of the rectification circuit to carry out filtering processing on the first direct current so as to obtain second direct current; the input end of the boost-buck circuit is connected to the output end of the first filtering circuit to regulate the second direct current according to a received control signal so as to obtain third direct current, the first output end of the boost-buck circuit outputs the second direct current, and the second output end outputs third direct current; and the controller is connected to the boost-buck circuit to send a control signal to the boost-buck circuit. Correspondingly, the invention also provides a control circuit for a heating device and a heating device. According to the technical scheme, the output voltage of the power supply circuit can be regulated at will to satisfy different voltage requirements of users and provide the stable voltage for the users.

The invention provides a distributed power supply fault recovery method and device, and relates to the technical field of power system fault recovery. The method comprises the following steps of: determining an optimal power supply combination scene; searching a shortest path between power supplies in the optimal power supply combination scene to generate an initial island; carrying out initial island search, dividing the island, and updating the range of the island; and judging whether the divided island meets safety evaluation constraint conditions or not, under the condition that the divided island meets the safety evaluation constraint conditions, formulating an island scheme, carrying out distributed power supply fault recovery according to the island scheme. With the method and device adopted, distributed power supply fault recovery is improved.

The invention discloses a detection information filtering method for radar target tracking. The detection information filtering method comprises steps as follows: S1, when radar tracks a target, to-be-filtered detection information and corresponding SNR (signal-to-noise) information are acquired from target detection information returned by detection each time; S2, the acquired to-be-filtered detection information is subjected to Kalman filtering, and when the designated amount of detection information is acquired, the step S3 is executed; S3, the designated amount of continuous detection information containing detection information at the current moment is acquired each time, part of data values are processed according to the data value change trend, and final detection information whichis acquired according to the detection information after integrated data processing and the corresponding SNR information is subjected to Kalman filtering until filtering of all detection formation iscompleted. The method has the advantages that the implementation is simple, influence caused by filtering signal fluctuation during Kalman filtering can be reduced, the filtering effect is good, theradar detection precision is high, and the like.

The invention relates to the technical field of water quality detector and particularly discloses a multi-parameter sensor for pH, conductivity and temperature. The multi-parameter sensor comprises a sensor shell and a glass electrode shell and is characterized in that the glass electrode shell is sleeved in the sensor shell, and the sensor shell is further provided with a conductivity measuring component and a temperature measuring element respectively. The conductivity measuring component comprises a first conductive electrode, an insulator and a second conductive electrode. An annular cavity is arranged between the sensor shell and the glass electrode shell, added fluid and compressed gas are filled in the annular cavity, and the glass electrode shell is provided with a liquid adding hole communicated with the annular cavity and the inside of the glass electrode shell. A measuring probe can simultaneously measure the three parameters of pH, conductivity and temperature, and accordingly the sensor is convenient for on-site mounting and unified introducing processing of signals. In addition, the cost performance of the multi-parameter sensor is increased greatly, and the service life of the multi-parameter sensor is prolonged greatly.

The invention relates to a manufacturing method of a SiC-based super-junction IGBT (Insulated Gate Bipolar Transistor) with low off-state loss. The manufactured SiC-based super-junction IGBT has low off-state loss. The manufacturing method comprises the steps of epitaxially growing a buffer layer of a first conductivity type at a SiC substrate of a second conductivity type; forming a drifting layer containing column regions of the first conductivity type and columns regions of the second conductivity type on the buffer layer, wherein the columns regions of the first conductivity type and the column regions of the second conductivity type are alternatively arranged in the transverse direction; epitaxially forming a body region layer of the second conductivity type on the drifting layer; forming a source region of the first conductivity type on the body region layer through ion implantation or epitaxial growth, and forming a base region of the second conductivity type through ion implantation; etching the SiC substrate so as to form a trench, wherein the trench crosses the body region layer and gets into the column region in depth; forming a gate oxidation layer in the trench; forming a gate electrode in the trench; forming source electrode metal contact in the source region and the base region, forming transmitting electrode metal contact in reverse side of the SiC substrate, and forming ohmic contact; and depositing a passivation layer on the grate electrode and the source electrode metal contact, and through-hole metal interconnection is performed.