Abb Research Ltd.

Other

Chinese Academy of Sciences

Abb Schweiz Ag

Abb Technology Ltd

Abb Power Grids Switzerland Ag

Bin Su

Youyi Li

Ying Yang

Lei Jing

Qianjin Liu

Torbjorn Einarsson

Kai Liu

Jie Ma

Lei Jiang

Jianping Wang

Zoran Gajic

Yanlin Song

Botong Li

Yongli Li

Li Chen

Shutao Wang

Jianzhong Fan

Wenjin Su

Wenwen Su

A method for preparing a nano carbon dioxide agent and an application of the agent are disclosed. The method takes cationic surfactant modified bentonite as a carrier, and the COnano agent prepared by loading cationic surfactant modified chitosan, graphene oxide and organic alkali modified hydrotalcite has the photocatalytic effect of nano materials, which can enhance photosynthesis, increase photosynthetic rate, inhibit light respiration at night, synthesize chlorophyll for crop growth, accumulate three essential elements of carbon, hydrogen and oxygen for crop growth, effectively absorb, synthesize and transform organic components such as nitrogen, phosphorus and potassium in soil, fully promote the gestation, growth and maturity of crops, and increases production and income. The COcapture agent of the disclosure can be used for both facility crops and field crops, and the CO2 capture agent under normal temperature and pressure has wide application.

Method for preparing nano carbon dioxide capture agent and application of same

The present invention discloses a catalytic phase change dielectric sphere for methanol combustion and a preparation method therefor. The catalytic phase change dielectric sphere for methanol combustion is mainly prepared from a high-temperature phase change material, an active material, a carrier material, a catalyst, a nano-semiconductor material, a nano-transition metal and an adhesive. A catalytic phase change dielectric solid sphere is prepared with a mixed pressing and sintering process, the methanol energy conversion rate reaches 87.5%, the furnace temperature of methanol combustion reaches 900&#xb0; C. or higher, and waste heat recovery is realized; or, a catalytic phase change dielectric microporous hollow sphere is prepared through electrostatic adsorption and in-site redox reaction, the methanol energy conversion rate reaches 99% or higher, the furnace temperature of methanol combustion reaches 1000&#xb0; C. or higher, and waste heat recovery is realized.

Catalytic phase change dielectric sphere for methanol combustion and preparation method therefor

The present invention discloses a method for identifying the fault by current differential protection and a device thereof. The method comprises: measuring the full component currents of the two terminals of a two-terminal line system and calculating the corresponding fault component current vectors; obtaining an operate value by calculating a first difference between an absolute value of the sum of the fault component current vectors and I; obtaining a restrain value by multiplying a second difference with a control factor, in which the second difference is calculated between the maximum of the absolute values of the fault component currents and Ior between the absolute value of the difference of said fault component currents and I; and identifying a fault as an external one or internal one by comparing the operate value with the restrain value. The solutions of the present invention achieve better reliability, sensitivity and faster speed than existing products.

Method for identifying the fault by current differential protection and device thereof

A method for identifying the type of faults occurred on a power line, characterized in that it comprises: calculating a fault point voltage on fault points based on terminal voltage and fault locations of the power line; adopting the fault point voltage corresponding to a maximum transition resistance as a setting value; comparing the fault point voltage on fault points with the setting value; and identifying the type of fault as a permanent type or a transient type based on the result of the comparison.

Method for identifying type of fault on power line

The present invention discloses a fast power swing unblocking method and apparatus for a distance protection in a power system, which is able to ensure fast phase-segregated tripping of distance protection for faults during a power swing (3-phase or 2-phase swing). The power swing unblocking method in a power system according to the present invention comprises calculating changing rates of impedances for all operating loops of the distance protection in the power system; and determining a fault loop based on the calculated changing rates. If there is a fault loop, a blocked distance zone for the fault loop is unblocked. Before calculating the changing rates, whether the power system is under a power swing is checked and a distance zone that might mal-operate under the power swing is blocked if it is checked that the power system is under the power swing. By applying this invention, the performance of the distance protection during power swings can be improved, and the distance protection can ensure faster and phase-segregated operation, which are very beneficial for the system reliability.

Fast power swing unblocking method and apparatus for distance protection in power system

Provided is a method of forming large-area directionally aligned nanowires on a silicon wafer surface with hydrophobic silicon pillars so as to form microelectrode-pair arrays, which belongs to the field of electronic circuit. The method includes grafting fluoroalkylsilane on the surface of a silicon wafer with hydrophilic silicon pillar arrays; increasing the contact angle between the surface of the hydrophilic silicon pillar arrays and water from 10&#xb0; to 150&#xb0; above and obtaining the silicon wafer with hydrophobic silicon pillar arrays; driving water solution containing materials used for forming nanowires to flow across the surface with the hydrophobic silicon pillar arrays uniformly, so that directionally aligned nanowires are formed on the tops of each two adjacent silicon pillars in the hydrophobic silicon pillar arrays; each of the nanowires connects the two adjacent silicon pillars together so as to form a microelectrode-pair, and a plurality of microelectrode-pairs constitute the microelectrode-pair arrays.

Method for forming microelectrode-pair arrays on silicon substrate surface with hydrophobic silicon pillars

The invention provides a method and apparatus for detecting communication channel delay asymmetry between transmission line protection devices. The method comprises: calculating, repeatedly, clock disparity between clocks of the protection devices and communication delays at different paths of the communication channel; comparing the latest calculated clock disparity and communication delays with previously calculated clock disparities and communication delays, respectively; determining a channel switching has happened if a change of the calculated clock disparity exceeds a first threshold, or a change of the calculated communication delays for any path exceeds a second threshold; and determining the channel delays as asymmetrical if a difference between the calculated communication delays of the different paths after the channel switching exceeds a third threshold.

Method and apparatus for detecting communication channel delay asymmetry

A synchronization method for current differential protection comprises: selecting a point on the transmission line protected by the current differential protection; measuring the current and the voltage of each of the terminals of said transmission line; calculating the compensating voltage at the selected point respectively according to the measured current and the voltage of the each terminal; detecting and calculating the synchronization error by comparing all the compensating voltages.

Synchronization method for current differential protection

A method and apparatus for fault identification in a transmission line are provided. The method may include measuring at an end of the transmission line when the transmission line has a fault to obtain a measured signal, comparing the measured signal with a predefined standard signal, the predefined standard signal having beat frequency characteristic; and identifying that the fault is a transient fault if the measured signal matches the predefined standard signal according to a result of the comparison, or the fault is a permanent fault if the measured signal does not match the predefined standard signal according to the result of the comparison.

Method and apparatus for fault identification in a power tansmission line

A method and a protection IED for supervising a secondary circuit of an instrument transformer in a power system are disclosed. The instrument transformer is connected to a power system component. The method includes: detecting, by a protection IED which is connected to the secondary circuit of the instrument transformer and protects the power system component, disturbances in a signal from the instrument transformer; and determining whether a failure occurs in the secondary circuit of the instrument transformer, according to both a disturbance detection result from the protection IED and another disturbance detection result from at least one of other protection IEDs. The other protection IEDs include protection IEDs which are connected to other secondary circuits of the instrument transformer or to secondary circuits of another instrument transformer connected to the power system component, and protection IEDs which are connected to other instrument transformers connected to other power system components connected to the same busbar as the power system component is connected to. The secondary circuit supervision solutions provide more reliable and sensitive performance and need very small amount of information to be collected.

Method and device for supervising secondary circuit of instrument transformer in power system

The present invention provides a new synchronization method named Multi-Node Echo Method (MNEM), which settles the problem of clock/data synchronization with asymmetrical channels. In MNEM, the echo messages are relayed among multi-node loop both by clockwise and anti-clockwise. Based on Multi-Node Echo Method, the invention further provides a method to detect symmetrical status of a communication network, a method to detect asymmetrical status of any channel in a communication network, and a method to calculate the sending and receiving delay values of any channel in a communication network, even when the channel is asymmetrical.

Growing community of inventors

Beijing, China

Bin Su