43 results about "Charge conservation" patented technology

The invention belongs to the technical field of physical and chemical test, and concretely relates to an apparatus for measuring the PCT curve of a material by using a solid state proton conductor, and a method thereof. The apparatus for measuring the PCT curve of a material by using a solid state proton conductor comprises a solid state proton conductor container, a DC source, a voltmeter, a transfer switch and an electric resistance furnace; when the material is measured, a DC voltage is applied to two electrodes of a proton conductor to measure the change curve of the current intensity of a circuit with the time, hydrogen in atmosphere electro-migrates to a material to be measured and capable of adsorbing hydrogen, and the hydrogen voltage can be calculated by measuring the electromotive force of a hydrogen concentration cell according to the principle of a conductor hydrogen concentration cell; and the content of hydrogen in the material can be calculated by measuring the change curve of the current according to a principle of charge conservation. The apparatus and the method enables the hydrogen pressure and the hydrogen content which are difficult to measure to be directly converted into electric signals, so it is easy to acquire and analyze data, thereby the apparatus and the method have the advantages of fast measurement, low cost and reliable data.

The invention relates to a liquid crystal compound and its preparation method and use. The liquid crystal compound has a structure shown in the formula (I). Through specific combination of two end groups of the compound shown in the formula (I), the compound has the characteristics of low viscosity and high dielectric anisotropy so that the liquid crystal composition containing the compound solves the problem that the existing TFT-LCD has a response rate not fast enough, voltage not low enough and a charge conservation rate not high enough.

The invention provides a charge pump circuit, which comprises twelve switches, three capacitors, six switch signals, a first clock signal and a second clock signal, wherein the six switch signals are used for controlling the twelve switches to be closed and broken off; the charge pump circuit comprises two input ends, namely a first input end and a second input end; the first clock signal and the second clock signal are respectively connected with the first capacitor and the second capacitor; according to the charge conservation principle of the capacitor and the charge pump circuit, the input voltage of the first input end and the input voltage of the second input end are respectively multiplied, the voltage of the first input end is reduced and then is output from the first output end and the voltage of the second input end is boosted and is then output from the second output end; and the voltage rise and voltage reduction are simultaneously realized by only using three capacitors. Therefore, according to the charge pump circuit, the area and the volume of a circuit board can be reduced.

The invention discloses a charge pump. The charge pump comprises N stages of voltage boosting circuits, wherein N in the N stages of voltage boosting circuits is an integer greater than 1; each stage of the voltage boosting circuit comprises a main capacitor; and in the output direction of voltage signals in the N stages of voltage boosting circuits, the main capacitance value in the former stage of the voltage boosting circuits is higher than or equal to that in the next stage of the voltage boosting circuits. Based on a condition of an unchanged main capacitive area, the main capacitance value in each stage is re-allocated; according to charge conservation, the charges in the next stage of the main capacitor are transmitted by the main capacitor in the former stage; if the main capacitance value of the former stage is greater than or equal to that of the next stage, the quantity of charges transmitted from the former stage to the next stage is increased, so that the speed of boosting the output voltage of the charge pump to a stable value is improved; when the main capacitance value of the former stage is higher, the more charges can be stored; and meanwhile, the capacitance value in the next stage is lower, however, the quantity of charges obtained by the capacitor in the next stage in one time is still increased.

The invention provides a method for calculating inverter bus current. By accumulating the charge of the upper and lower half bridges on the AC side of the inverter, according to the principle of charge conservation, the charge of the positive electrode of the DC bus is equal to the charge of the upper bridge, and the charge of the negative electrode of the DC bus is equal to the charge of the upper bridge. The amount of charge is equal to the amount of lower bridge charge. In this way, the DC current on the bus side can be calculated according to the charge amount of the upper bridge or the lower bridge accumulated on the AC side of the inverter in a calculation cycle and the duration of the calculation cycle. The busbar current calculation scheme avoids the dispersion characteristics of the physical sensor and the failure of the sensor, saves the DC current sensor, and reduces the product cost. In addition, the calculation accuracy is comparable to that of physical sensors, and the accuracy is stable, and the accuracy is not degraded under fault conditions, avoiding the complex calculation of losses in the power balance method.