38results about How to "High voltage gradient" patented technology

The invention provides a preparation method of large-discharge-current-capacity and low-residual-voltage voltage-sensitive ceramic used for an ultrahigh voltage power transmission system. The ceramic is prepared from zinc oxide ZnO, bismuth oxide Bi2O3, antimonous oxide Sb2O3, manganese dioxide MnO2, chromic oxide Cr2O3, cobalt oxide Co2O3, silicon dioxide SiO2, silver oxide Ag2O, Ga(NO3)3 and aluminium nitrate Al(NO3)3. The method has the advantages that the leakage current is restrained, the ageing performance of a ZnO voltage-sensitive resistor manufactured according to the formula is more stable by adding elements Al and Ga together, and the defect that when only Ag ions are added, the ageing performance of the voltage-sensitive resistor is not stable is overcome.

The invention relates to a preparation method of a zinc oxide varistor sheet. The method includes the steps of: preparing a green body by using zinc oxide as the main material and auxiliary materials including bismuth oxide as raw materials, sealing the green body and then performing microwave sintering, and the microwave sintering process is as follows: heating to 1000-1100° C., Heat preservation for 1-10min; then cool down to 850-900°C, heat-retain for 1-3h, and finally cool to room temperature to obtain a zinc oxide varistor sheet. The method proposed by the invention greatly shortens the sintering time, reduces the energy consumption in the sintering process, and improves the electrical properties such as the voltage gradient and energy tolerance of the zinc oxide varistor sheet.

The invention discloses a piezoresistor material. The piezoresistor material is prepared from the following raw materials in parts by weight: 98-100 parts of zinc oxide, 50-52 parts of yttria, 3-5 parts of titanium dioxide, 50-52 parts of ytterbia, 2-4 parts of stannic oxide, 1-3 parts of selenium oxide, 5-7 parts of strontium titanate, 2-4 parts of rhenium oxide, 2-4 parts of manganese carbonate, 6-8 parts of silicon dioxide, 4-6 parts of aluminum nitrate and 10-12 parts of rare earth sinter. Yttrium ions and ytterbium ions, with radii close to those of zinc ions, are introduced, so that a traditional formula with zinc oxide as the main component is replaced with a new formula with zinc oxide, yttria and ytterbia as main components. In combination with various additives in the new formula, the prepared piezoresistor material has higher nonlinear coefficients, lower leakage currents, higher heavy current resistance capacity and higher voltage gradient.

The invention discloses an electric osmosis filter pressing based sewage sludge co-dehydration device, comprising an electric osmosis squeezing container (3), an anode plate (4) and a cathode plate (5), wherein the anode plate (4) and the cathode plate (5) are arranged in the electric osmosis squeezing container (3), sludge particulates move towards the anode plate and water molecules move towards the cathode plate under the influence of an electric field force, and a pressure is exerted between the anode plate and the cathode plate such that electrically osmosed water flows out of an electric osmosis squeezing dehydration device. After the above electric osmosis dehydration is completed, a low water content of sludge of the anode plate (4) is realized, when the sludge becomes dry, the electric osmosis dehydration is stopped, and the pressure between the anode plate (4) and the cathode plate (5) is increased to realize an ultra-high pressure mechanical filter pressing dehydration, so that the water content between the anode plate and the cathode plate is uniform. According to the electric osmosis filter pressing based sewage sludge co-dehydration device disclosed by the invention, as a co-dehydration means in the combination of an electric osmosis coupling dehydration and an ultra-high pressure mechanical dehydration is employed, energy consumption for the dehydration is reduced greatly, and a lower water content of the sludge treated according to the invention is realized.

The invention discloses a nonlinear cylindrical pressure sensitive resistor and application thereof. The nonlinear cylindrical pressure sensitive resistor is composed of a pressure sensitive resistor ceramic wafer and a non-continuous electrode. Due to doping of a zinc oxide material in the pressure sensitive resistor ceramic wafer, grains of the zinc oxide are refined, the surface density of the pressure sensitive resistor ceramic wafer is increased, the characteristics of the pressure sensitive resistor are improved, and the current-force impact resistance and nonlinear coefficient of the resistor are improved, so that the pressure sensitive resistor has high voltage gradient and beneficial electrical properties, reaches a nanosecond over-voltage response speed and is fast in over-voltage recovery and zero in follow current. The pressure sensitive resistor disclosed by the invention is safe and non-toxic in material and harmless to the human body and environment and can be widely applied to over-voltage protection of power diodes, silicon stacks, medium / low-power silicon controlled rectifiers and the like.

The invention discloses a safe environment-friendly nonlinear piezoresistor and application thereof. The safe environment-friendly nonlinear piezoresistor is composed of a piezoresistor ceramic wafer and a conductive electrode. The piezoresistor ceramic wafer is composed of zinc oxide, manganese dioxide, silicon dioxide, titanium dioxide, nonacobalt octasulfate, dinickel trisulfate, silicon carbide, zirconium nitride, zirconium titanate and copper calcium titanate. The surface density of the piezoresistor ceramic wafer is increased, the characteristics of the piezoresistor are improved, and the current impact resistance and nonlinear coefficient of the resistor are enhanced, so that the piezoresistor has higher voltage gradient and favorable electric properties. The overvoltage response speed reaches the nanosecond level; and the piezoresistor can quickly restore without after flow after overvoltage. The piezoresistive material is safe and nontoxic, and is harmless to the human body and environment.

The invention discloses a piezoresistor with a low residual voltage ratio and application of the piezoresistor. The piezoresistor with the low residual voltage ratio consists of a piezoresistor chip, a silicone rubber sealing layer, an insulated sealing layer, an electrode and an electrode lead wire. A zinc oxide material is doped, so that grain sizes of zinc oxide are refined, and surface density of a piezoresistor is increased, and therefore, the purpose of reducing the residual voltage ratio of the piezoresistor is achieved, current power impact resistance and a nonlinear coefficient of the piezoresistor are improved, so that the piezoresistor has relatively high voltage gradient.