6 results about "Partial discharge" patented technology

A method for bounce suppression of a valve member operated by a piezo actuator during the closing phase of a valve in an internal combustion engine, having the following steps: partial discharging of the piezo actuator, whereby the valve member is braked even before reaching the valve seat, interruption of the discharge of the piezo actuator, whereby the piezo actuator is upset by the valve member and builds up an electric charge, renewed discharging of the piezo actuator, the residual charge after partial discharge and the charge built up during the charge interruption being at least partially dissipated. It is provided, according to the present invention, briefly to interrupt the discharge process, whereby the piezo actuator absorbs the energy of the valve member and, even before an elastic rebound takes place, the piezo actuator is discharged again, in order to dissipate the energy absorbed by the piezo actuator.

The invention relates to the field of transformers, and provides a continuous dry-type transformer winding with free arrangement in the radial direction and a processing method thereof. The continuousdry-type transformer winding comprises an electromagnetic wire and an insulating inner cylinder, wherein the electromagnetic wire is wound on the insulating inner cylinder, the winding is a structurethat the electromagnetic wire is freely arranged in the radial direction and continuously wound on the whole in the axial direction, and the electromagnetic wire and the insulating inner cylinder areintegrally cast by resin. According to the winding method, the electromagnetic wire is wound from the winding starting end to the other side and is continuously wound on the whole in the axial direction, the electromagnetic wire is freely stacked on a winding die to form the radial height of the winding, and inter-layer insulation or inter-turn insulation is not required to be placed. According to the invention, the production efficiency is greatly improved, and materials are saved; meanwhile, the space occupancy rate of the wire in the winding is increased, the structure is simple, the winding is simple and convenient, the mechanical performance is good, the impact resistance is strong, the axial voltage gradient distribution is uniform, the inter-turn potential difference is small, thepartial discharge capacity is low, and the electrical performance is greatly improved.

The invention discloses a high voltage ceramic capacitance couple sensor with low partial discharge magnitude, which comprises a metal base, a ceramic capacitance core, a top electrode, a metal electrode and an external lead. The ceramic capacitance core is provided with a top copper electrode and a bottom copper electrode, a metal rod is arranged between the top copper electrode on the ceramic capacitance core and the top electrode, the bottom copper electrode on the ceramic capacitance core is connected with a lead bolt through a metal belt, the lead bolt, the metal belt, the ceramic capacitance core, the metal rod and the top electrode are connected successively from bottom to top and molded through epoxy resin casting, casting epoxy resin forms an encircling-coating-shaped epoxy resin coating shell, the top electrode is embedded in the upper portion of the epoxy resin coating shell, the lead bolt is embedded in the lower portion of the epoxy resin coating shell, the metal electrode is arranged on the top electrode, the external lead is connected with the metal electrode, the metal base is connected with the lower portion of the epoxy resin coating shell fixedly, and sampling impedance and a coaxial wire base are arranged inside the metal base. The sensor has a compact structure and the partial discharge magnitude of the sensor is low.

The invention discloses a transformer substation switch cabinet partial discharge state evaluation method based on a high-dimensional index. The method comprises the following steps: collecting phase decomposition partial discharge PRPD atlas data of a transformer substation switch cabinet; spectrogram construction and statistical characteristic calculation are carried out on the obtained partial discharge PRPD spectrogram data; performing preprocessing on statistical characteristics obtained by calculation of the atlas data, and constructing a spatio-temporal data set matrix; and based on a random matrix theory, sequentially selecting matrixes on the spatio-temporal data set matrix by adopting a moving sliding window method, constructing a statistical magnitude by utilizing a Chebyshev polynomial T3 to judge whether an abnormal value occurs, calculating the statistical magnitude of the matrix selected by a sliding window, and evaluating the state of the substation switch cabinet. The operation state of the transformer substation switch cabinet can be monitored, and the monitoring efficiency and accuracy of the transformer substation switch cabinet are improved.

The invention discloses a partial-discharge-free self-boosting multi-transformation-ratio standard voltage transformer and a test method, and relates to the technical field of electric energy metering. A voltage booster and a standard voltage transformer are designed in an integrated mode, the voltage transformer comprises a voltage booster coil, a standard coil and a compensation coil, the voltage transformer can be used for achieving error measurement and partial discharge and voltage withstand tests of the voltage transformer with four voltage levels of 6 kV, 10 kV, 20 kV and 35 kV and eight transformation ratios, the number of testing equipment of the transformer testing device is reduced, it is ensured that the accuracy levels of the eight transformation ratios all reach 0.01 level, the partial discharge amount of the standard device and the voltage booster is smaller than 5 pC, and efficient and accurate implementation of multiple tests is ensured.

The invention provides a device for improving the partial discharge detection sensitivity of a power distribution cable. The device comprises an A-phase HFCT, a B-phase HFCT and a C-phase HFCT, also comprises an A-phase conditioning circuit, a B-phase conditioning circuit and a C-phase conditioning circuit which are correspondingly connected with the A-phase HFCT, the B-phase HFCT and the C-phaseHFCT, and also comprises an analog-to-digital converter A/D, a random access memory DDR, a programmable gate array FPGA and a microprocessor ARM which are connected in sequence, wherein the A-phase conditioning circuit, the B-phase conditioning circuit and the C-phase conditioning circuit are all connected with the analog-to-digital converter A/D, and the microprocessor ARM is further connected with the random access memory DDR. The invention further provides a method for improving the partial discharge detection sensitivity of the power distribution cable. According to the invention, the efficiency, the signal-to-noise ratio and the sensitivity of partial discharge offline detection can be significantly improved, and the accuracy of partial discharge detection is improved.