96 results about "Iec standards" patented technology

With audio data reduction on the basis of ISO/IEC standard 11172-3, a frame length varying by 8 bits is used at a sampling frequency of 44.1 kHz in order to arrive, on average, at a particular fixed data rate. The lengthening of a data frame is signalled by a padding bit in the header of the frames. The invention dispenses with evaluation of the padding bit. Instead, the mean frame length L is calculated, L is rounded down to the next integer, for the subsequent frame it is first established whether the expected sync word for this frame appears, and, if this is so, this frame is decoded without taking into account the padding bit, but if the expected sync word for this frame does not appear, the decoding of the frame is started one 8-bit later without taking into account the padding bit.

A system for decoding variable length coded DVC data and methods of operating the same result in a variable length decoder engine that receives video frames having a plurality of digital interchange format (DIF) sequences and provides contiguous decoded run-length amp pairs. The variable length decode engine comprises a concatenation engine configured to contiguously format a plurality of DIF blocks of a DIF sequence to provide contiguous DCT blocks. The concatenation engine has a controller that utilizes several passes capable of running simultaneously to return the DIF blocks coded according to IEC standards to their original variable length sequences. A run-length amp pair generator coupled to the concatenation engine configured to decode the contiguous DCT blocks to provide the run-length amp pairs.

The present disclosure provides a method and system for operation of substations in which protection, control and measurement devices (e.g., Intelligent Electronic Devices (IEDs)) exchange operational data over a data network, for example, according to IEC standard 61850. During maintenance, commissioning and fault situations, when one or several IEDs are inoperable, the data that these IEDs would have produced is substituted to ensure availability of the substation. To this effect, a dedicated substitute device is permanently installed that can take the role of any IED, and that is automatically configured out of a standard configuration description (SCD) file that describes the SA system.

The invention discloses a method for diagnosing a fault of a transformer on the basis of a clustering algorithm and a neural network. The method comprises the following steps that (a) the type of the fault is determined according to an IEC standard and a DL/T722-2000 guideline, and the characteristic quantities of a fault sample set are selected from an original sample set; (b) clustering is carried out on samples by utilizing a K-means clustering method; (c) an RBF neural network is established; (d) parameter learning is carried out to determine the number, the center position, the width and the output weight of hidden layers; (e) optimization training is carried out by adopting PSO to determine the positions of the centers of the hidden layers, and the number, the width and the weight of the hidden layers are determined by utilizing a test method, a minimum distance method and a pseudo-inverse method respectively; (f) training samples are input, the posterior probability is solved, and the type of the fault is judged. According to the method for diagnosing the fault of the transformer on the basis of the clustering algorithm and the neural network, the training samples and the test samples can be evenly divided from the total samples, more complete test on the neural network can be carried out by good test samples, and therefore the neural network can be evaluated correctly and reasonably.

The invention discloses a method for calculating the conductor temperature of a cable. The method comprises the following steps: calculating a relation expression between a calculated value of the conductor temperature of the cable in a steady state and a heat-conductivity coefficient of a structural material of each layer of the cable by using a thermal-circuit method; calculating a functional relation between the heat-conductivity coefficient of the structural material of each layer of the cable and a corresponding sensitivity by using a sensitivity principle, and calculating the value of a sensitivity corresponding to the heat-conductivity coefficient of the structural material of each layer of the cable according to the functional relation; and adjusting the value of a selected heat-conductivity coefficient according to the value of the sensitivity, then calculating the conductor temperature of the cable according to the adjusted value of the heat-conductivity coefficient. The invention also provides a device for calculating the conductor temperature of the cable. By using the technology of the invention, the conductor temperature can be calculated accurately and the current-carrying capacity of the cable can be assessed accurately; and the calculated value of the conductor temperature of the cable is significantly improved on the basis of a calculated value stipulated in IEC (international electrotechnical commission) standards, thereby avoiding the occurrence of a problem that a result of the conductor temperature of the cable, calculated according to the IEC standards, has an excessive margin and a large error; and the method and device disclosed by the invention provide references for the real-time monitoring of the cable and the improvement of transmission capacity and operation of the cable.

The invention discloses a dynamic modeling method of a conventional substation based on the IEC standard, which includes the steps as follows: firstly, building an object-oriented model; secondly, obtaining an entity model through mapping and supplementation; thirdly, building a UCIM model of a master station system as per the entity model; and fourthly, updating the UCIM model. The method effectively solves the problems of communication collision and efficiency between communication of an information point oriented dispatching master station and communication of an object-oriented substation, improves the efficiency of technology upgrade and innovation of a great amount of conventional substations, and reduces working pressure of substations and management maintenance staff for dispatching automatization.

This invention provides a power conversion apparatus capable of improving the power factor of the power supply and making the harmonic component of the power supply match or very closer to the IEC standard, and an air conditioner using the same. The power conversion apparatus includes a conversion section for rectifying and smoothing an AC voltage supplied from an AC power supply and converting the AC voltage into a DC voltage, an inversion section for converting the DC voltage prepared by conversion into an AC voltage and supplying the AC voltage to a load, a reactor series-connected to the power supply side of the conversion section, a booster for forcibly short-circuiting the AC power supply via the reactor, and a controller for setting the short-circuiting conduction time by the booster so as to optimize the power factor of the AC power supply in accordance with any one or a plurality of differences between the voltage of the AC power supply, the inductance of the reactor, the circuit arrangement of the conversion section, and an input power. The air conditioner drives a compressor for forming a refrigeration cycle using the power conversion apparatus.

The invention discloses a wind generator set engine room transfer function subregional fitting method. The method comprises the steps of 1, determining a target set, and collecting running data of a wind measurement mast and the target set within the same time; 2, determining the hub height H of the target set and calculating average wind speed data of the wind measurement mast at the height H; 3, utilizing IEC standards and the average wind speed data calculated in the step 2 as the basis, and removing abnormal running data in the step 1; 4, calculating a transfer function of an engine room of the target set, and correcting the transfer function, wherein the step 4 comprises the substep 4-1 of conducting fitting on a low wind speed area and a high speed wind speed area which are obtained by using the rated wind speed value as the limit and the substep 4-2 of calculating a fitting function order of the low wind speed area and a fitting function order of the high wind speed area respectively. By correcting the wind speed of the engine room, the wind speed of free flow at the center of a wind generator set wind wheel is obtained, and a power curve of the performance of the set can be more objectively reflected.

The invention discloses a phase difference correction method applied to self-adaptive sampling of a power grid having a wide range of frequency fluctuation. The method overcomes lower measurement precision of phase difference correction methods upon dynamic variation of a fundamental frequency by increasing computing of frequency change rate, predicting real-time fundamental frequency for each measurement, correcting sample frequency so as to carry out measurement. Therefore, the method herein effectively reduce spectral frequency leakage and increases measurement precision. The method herein conducts simulation analysis on variety-frequency power grid signals by using phase difference correction method which is based on Harming window, verifies the feasibility of self-adaptive sampling methods. The method can produce high magnitude and phase measurement precision when a frequency is stable, and can also reach IEC standard requirements for magnitude measurement precision when the fundamental frequency has wide range of fluctuation, so that the method herein effectively reduce phase difference errors, can real-time reflect state of a system, and is suitable for on-line monitoring harmonic waves of a power grid which has a wide range of frequency fluctuation.

The invention, which belongs to the solar cell device preparation field, relates to a lightweight film solar module and a manufacturing method thereof. A technology scheme is characterized in that: (1) toughened glasses or half toughened glasses are used to substitute common float glasses as a substrate of a film solar cell; (2) a packaging material possessing a reflection effect is adopted to substitute a titanium dioxide back reflection layer or a metal back reflection layer and a transparent packaging material; (3) a polymer composite film containing a metal layer is used as a back plate of the film solar cell; (4) an insulation tape is used to paste an electrode lead-out wire of a junction box; (5) a glue or an adhesive tape is used to seal film solar module edges; (6) a hook, which substitutes an aluminum frame, is bonded on the back of the film solar module so that the solar module can connect with an installing support. In the invention, the film solar module can be guaranteed to satisfy an IEC standard request; weight of an unit area of the film solar module can be reduced by 42%; simultaneously, production costs can be reduced and a production technology can be simplified.

The invention relates to a polyamide-imide insulating varnish. The polyamide-imide insulating varnish is characterized in that the varnish comprises the following components in parts by weight: 100-120 parts of polyamide-imide solution and 2-5 parts of sepiolite material, wherein the polyamide-imide solution mainly comprises the following components in parts by weight: 20-35 parts of polyamide-imide resin and 20-60 parts of organic solvent; the organic solvent is one or a combination of N-methylpyrrolidone, chlorobenzene, bromobenzene, dichlorobenzene, dibromobenzene, 1-tetralone, fenchone, phorone and isophorone; and the sepiolite material mainly comprises sepiolite. The polyamide-imide insulated enamel wire provided by the invention forms a homogeneous stable system, the surface friction coefficient is below 0.30, and each index meets the International Electrotechnical Commission (IEC) standard requirement; and the polyamide-imide insulating varnish is suitable to be used as the enamel wire insulating varnish for coating the surface of the copper wire.

The invention discloses a fan authentication test system analysis platform. For fan authentication test analysis software developed based on FAMOS, BLADED and MATLAB, five modules, namely a data analysis module, a power test module, a performance test module, a load test module and a system identification module are distinguished; mainly aimed at professional equipment based on GL/IEC standards, data formats and IEC test standard specification requirements are tested; and according to the GL/IEC standards, a test report is automatically made. The platform can realize not only functions of test data calibration, captured matrix analysis, sector screening, scattered point curve graph analysis, load rain-flow analysis, time-domain spectral analysis, test and simulation analysis comparison, theoretical simulation model system identification and the like but also automated generation of a fan performance test analysis report, a power test analysis report and a load test analysis report in a GL-D professional format. Moreover, the wind generator unit authentication test data processing is more systematized and modularized.

The invention provides a flexible direct current power transmission converter performance testing platform and a control method thereof. The direct current side of a first modularized multi-level converter and the direct current side of a second modularized multi-level converter are connected in a back-to-back mode, and three phases of the alternating current side of the first modularized multi-level converter are connected with three phases of the alternating current side of the second modularized multi-level converter correspondingly, so that a power circulation pathway is formed; a test power source is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter and provides loss power for steady-state operation testing; a short circuit generator is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter. According to the testing platform and the control method thereof, the requirement for power grid capacity is low; meanwhile, the direct current side power supply mode is adopted in the testing platform, and therefore the single test power source is adopted for the whole platform. With regard to test items of the short circuit and over-current turn-off required by IEC standards, due to the fact that the basic structure of the platform is basically the same with that of practical engineering, the short circuit test and the over-current turn-off test can be set through the platform according to double-pole short-circuit faults in a practical flexible direct current power transmission system.

The invention relates the modifier, which is used to make and modify high-heat polyurethane paint wire insulating paint. The modifier comprises 20-30% phenolic resin, 10-20% amido resin, 10-20% acrylic resin, 2-5% organosilicon surface active agent, and 30-60% M-and P-cresols. The method comprises the following steps: putting the phenolic resin, amidogen resin, acrylic resin and organosilicon surface active agent into M-and P-cresols, then mixing, dissolving, heating to 40-60Deg.C, stirring, and getting the mixture. The modifier is used to make high-heat polyurethane paint wire insulating paint. The method improves the continuity and pinhole property of polyurethane paint wire insulating paint, without reducing heat-proof grade of paint. The properties of the paint modified by the modifier meet international electrician IEC standard.

The invention is a proposed extension to ISO/IEC standard 14496-6 (DMIF) and is partly described in ISO/IEC working document 14496-6 V2 WD 3.0. Specifically, the invention is a novel method for allowing the delivery of a streamed multimedia service across a heterogeneous network configuration without establishing a new session. In one embodiment, the invention is applicable to a scenario in which first and second terminals are directly connected to a first network and indirectly connected to a second network via respective access networks. Each terminal comprises terminal middleware and there is also a network middleware component connected to the terminals and to the access networks and to the second network. In essence, the method comprises the steps of establishing a session between the first and second terminals through the first network; transmitting a first plurality of multimedia streams from the first terminal to the second terminal across the first network, each stream being associated with a respective desired quality of service (QoS); measuring the QoS of each of the first plurality of streams; and if the measured QoS of one or more of the first plurality of streams is less than the respective desired QoS, transmitting said at least one or more of the first plurality of streams through the access networks and the at least one second network during said session.

Digital video data streams that conform to standards such as the ITU-T H.263 and MPEG-4 ISO/IEC standards are compressed to reduce the amount of memory needed to store these streams. Information for groups of pixels are compressed into segments of encoded information. Each segment of encoded information includes luminance values that are rounded and truncated, the full-length values of chrominance information for the first pixel in the group, and codes that represent differences in chrominance values between adjacent pixels in the remainder of the group. A special "escape" code is used to represent the chrominance value for a pixel whenever the difference in chrominance values between that pixel and the preceding pixel exceeds a threshold.

The invention discloses an adjacent harmonic and inter-harmonic separation and measurement method under an IEC (international electrotechnical commission) framework. The method includes the following steps: firstly, performing discrete sampling on a power grid signal; secondly, performing ten-cycle Hanning window addition DFT/FFT (discrete Fourier transform/fast Fourier transform) spectral transformation on a sampling value according to IEC standards so as to obtain a spectrum; thirdly, multiplying the spectrum by rotary phase factors to obtain a new spectrum; fourthly, solving a vector sum of neighboring spectral lines of the new spectrum so as to offset sidelobe interference of rest components on the new spectrum, and solving corresponding frequency, a frequency deviation value and amplitude phase via a spectral line phase cancellation interpolation method; fifthly, rejecting spectrum leakage values of a fundamental component and the rest components at spectral line attention positions on a frequency domain; sixthly, solving a harmonic spectrum value to obtain parameters of h subharmonics, and solving parameters of inter-harmonics adjacent to the h subharmonics. By the method, the problem that the parameters of the two adjacent harmonics and inter-harmonics cannot be measured accurately during limited data asynchronous sampling is solved.

The invention discloses a harmonic wave measurement method based on spectral energy interpolation. According to ten cyclic wave detection environments meeting the IEC standard, concrete parameters of a certain component are detected out accurately, and an IEC method only can roughly detect out the amplitude of signals within the certain frequency band; from the point of view of spectral energy in a signal frequency domain for the first time, transformation and interpolation of an energy spectrum are carried out by multiplying the frequency spectrum by a rotation phase factor, influence of overlaid leakage of sidelobes of the frequency spectrum is eliminated by mutual offset of energy of interference components, and the detection precision of the frequency, the amplitude and the phase position is improved; when the components in signals are likely submerged in noise signals, main signals are highlighted through transformation of the spectrum energy, and therefore usable signals are extracted from the noise signals effectively. The method is based on a DFT/FFT algorithm recommended by the IEC standard, the principle is simple, the effect and stability are good, and the method has certain engineering application value and good application prospects.

A system, method, and device for protecting an induction motor are disclosed. The exemplary system may have a module for determining the current drawn by the motor and a module for determining the state of the motor. The system may calculate a used thermal capacity based on a first formula when the motor is in an active state. The system also calculates the used thermal capacity based on a second formula when the motor is in an inactive state. When the used thermal capacity attains a threshold, the relay is tripped thus removing current to the motor and preventing motor from overheating. A method to derive thermal time constants from desired trip time limits (such as those defined by IEC standards or the thermal limit curves provided by motor manufacturers) is also presented. For example, the thermal time constants can then be used in tacking motor used thermal capacity throughout various motor states.

The invention relates to self-lubricating polyamide imide enameled wire insulating paint, which comprises the following compositions according to the portions by weight: 20 to 35 portions of polyamide imide resin, 10 to 30 portions of isocyanate, 1 to 10 portions of a lubricant, 1 to 5 portions of an organosilicon surfactant, and 30 to 60 portions of N-methyl pyrrolidine, wherein the lubricant consists of polyphenyl thioether and melamine cyanurate. According to a formulation, the polyamide imide resin, the isocyanate, the lubricant and the organosilicone surfactant are mixed and dissolved in the N-methyl pyrrolidine to prepare a stable transparent liquid oily substance after even agitation at a temperature of between 40 and 60 DEG C. The insulating paint has the advantages of remarkably improving the lubricating performance and friction coefficient of polyamide imide enameled wire paint film while not reducing performance indexes at the same time through directly adding a mixture of the lubricant and the organosilicon surfactant with the performance indexes meeting IEC standards, greatly reducing the friction coefficient and meeting the requirements of high-speed winding.

The invention discloses a high-power electromagnetic pulse protection module used for a power line. The whole high-power electromagnetic pulse protection module is a comprehensive protection module formed by integration of a time domain transient suppression circuit and a frequency domain wave filtering circuit, and the whole module conducts shielding by using a metal housing. The time domain transient suppression part is formed by combining a voltage dependent resistor high in response speed and a TVS diode in a high-low cooperation mode and includes a voltage dependent resistor M, a voltage dependent resistor M1, a voltage dependent resistor M2, a decoupling inductor L1, a decoupling inductor L2 and the TVS diode; the rear portion of the TVS diode is connected with the frequency domain wave filtering part; the frequency domain wave filtering part is formed through the combination of a pi type wave filtering circuit and a capacitor wave filtering circuit, and includes a capacitor C1, a capacitor C2, an inductance coil L, a capacitor C3 and a capacitor C4, the capacitor C1, the capacitor C2 and the inductance coil L together form the pi type wave filtering circuit, and the capacitor C3 and the capacitor C4 are connected between grounding wires to filter out common-mode interference. According to the module, all circuits are simple, the protection effect passes the inspection of a testing system built by reference to the IEC standard, and the module has a better application and popularization prospect.

The invention provides a flicker precision detection method for a digital electric energy quality monitoring terminal and a system thereof. The method comprises the steps that standard signals meeting the IEC61850-9-2 requirement are transmitted to the digital electric energy quality monitoring terminal; sampling is performed on the standard signals by the digital electric energy quality monitoring terminal and an MMS message is outputted; minute data of a short-term flicker index are confirmed according to the MMS message; and a short-term flicker measured value of the digital electric energy quality monitoring terminal is confirmed according to the minute data of the short-term flicker index. The IEC standard, detection precision and dynamic flicker detection capacity of the digital electric energy quality monitoring terminal can be identified, and flicker test capability of the electric energy quality terminal used for a digital transformer substation can be conveniently and rapidly assessed.

The invention designs a polyamide imide insulating paint, which is characterized by comprising 100-120 parts by weight of polyamide imide solution and 2-5 parts by weight of montmorillonite material, wherein the polyamide imide solution mainly comprises the following components in parts by weight: 20-35 parts of polyamide imide resin and 20-60 parts of organic solvent, and the organic solvent is one or more of N-methyl pyrrolidone, chlorobenzene, bromobenzene, dichlorobenzene, dibromobenzene,1-tetralone, fenchone, phorone and isophorone; and the montmorillonite material mainly comprises montmorillonite. According to the invention, the polyamide imide insulating enamelled wire forms a homogeneous and stable system, has the surface friction coefficient below 0.30 and indexes satisfying standard requirements of international electrotechnical commission (IEC), and is particularly suitable to be used as enamelled wire insulating paint for coating the surface of a copper wire.

The invention discloses a wave beam transmitting method of an ultrasonic diagnostic apparatus and the ultrasonic diagnostic apparatus. An array element of a probe is controlled to transmit ultrasonic according to the combination of a set high-power transmission mode and a set transmission-stop mode, at least one parameter of the high transmission power and high-power transmission duration of the high-power transmission mode and the transmission-stop duration of the transmission-stop mode is obtained by calculating the normal transmission power of the continuously working apparatus under current transmission conditions. According to the invention, not only can the quality of ultrasound patterns be improved, but also the surface temperature rising of the probe can be controlled to meet the requirements of IEC standard.

The invention relates to a pump circuit (300a+b), which serves as a charge pump while being provided for an electronic ballast (EVG) for the high-frequency operation of one or more series-connected low-pressure gas discharge lamps (LA1, LA2). Said ballast serves to rectify the alternating voltage (UNetz) supplied by a power supply mains, to filter mains harmonic waves, and to carrying out a method, which is based on an expanded Active Valley Fill (AVF) principle and which is provided for correcting the power factor lambda (PFC) in order to enable an approximate sinusoidal current consumption, for example, in accordance with IEC Standard 1000-3-2. To this end, a pump capacitor (C2) of a pump circuit (300a+b) is supplied with power by the galvanically separated decoupling of the current flowing through the lamp so that when the lamp fails, the pump mechanism automatically comes to a standstill whereby eliminating the problem of load shedding.

The invention relates to a humid heat simulation test accelerating method for a photovoltaic module, which comprises the following steps of: selecting a material sample for the photovoltaic module, wherein the testing environment is 121+/-2 DEG C/100+/-5percent RH or 121+/-2 DEG C/85+/-5percent RH; and performing a humid heat simulation test of the material sample for the photovoltaic module by utilizing the testing environment. The humid heat simulation test accelerating method can be equivalent to 1,000 hours of a standard humid heat test in international electrotechnical commission (IEC) within 60 hours, is efficient and fast, can fulfill the aim of a long-term exposed humid heat test outdoors through a short-term test indoors, solves actual problems of a development party and an application party, and facilitates application and promotion of the material of the photovoltaic module.