Abstract: The present invention discloses a Bipolar VSC-HVDC and UPFC Hybrid Topology and its operation method. The first control circuit includes a positive and a negative circuit at the series side, in which the VSC converter can operate in bipolar mode; the second control circuit includes a positive and a negative circuit, in which the VSC converter can operate in bipolar mode; the third control circuit is the same as the second control circuit in terms of structure; the positive electrode and negative electrode of the second control circuit are connected to the DC bus via a DC breaker respectively; the other end of the DC transmission line is connected to the third control circuit via a DC breaker.

Abstract: The present invention provides an online monitoring circuit of the series compensation spark gap divider return circuit. Said series compensation spark gap divider return circuit includes a voltage equalization link and a voltage sampling link. Said voltage link includes the capacitor C which series said voltage equalization link. Said online monitoring circuit includes the voltage sampling input module, series compensation current input module and the compare module. Said sampling voltage input module after amplified the voltage of the two ends of the series capacitor C converts it into direct current signal.

Abstract: An apparatus for evaluating an electrical insulator includes: a frame having a base and a pair of spaced-apart resilient arms each having a distal end; and a flexible probe disposed between the arms, the flexible probe being generally U-shaped and having a pair of distal ends, each distal end of the probe being connected to a respective distal end of one of the arms.

Abstract: A method for inspection of tubes in a boiler is disclosed. The method of inspecting includes the steps of providing an apparatus having a sensor and a housing adapted to contain the sensor. The method further including the steps of extending the apparatus into a tube bundle until a desired tube for inspection is reached; rotating the apparatus until the sensor is positioned over the tube to be inspected; clamping the housing around the tube to be inspected, thereby clamping the sensor around the tube; transmitting a pulse of guided waves into the tube to be inspected and detecting reflected signals; and acquiring data from the reflected signals and determining the condition of the tube.

Abstract: A modeling method and system for a diode clamped cascaded multi-level converter. All corresponding diodes of each bridge arm are equivalent to an auxiliary diode; all corresponding capacitors of each bridge arm are equivalent to a controlled voltage source; and power modules of each bridge arm are connected in series to be equivalent to an equivalent module, the equivalent module comprising a loss resistor and a composite equivalent model connected to the loss resistor. Since a plurality of components, at the same positions, in each power module of each bridge arm of the diode clamped cascaded multi-level converter are equivalent to a component, the node voltage equation order can be reduced, the simulation efficiency is improved, and the simulation efficiency cannot be reduced with the increase in the number of power modules.

Abstract: The invention provides a lithium battery and redox flow battery energy storage systems hybrid energy storage power station real-time power distribution method and system. The system comprises a communication module, a data storage and management module, a gross power coordination control module and a real-time power distribution module. The said method and system not only can complete the real-time distribution of each battery energy storage units in the battery energy storage station, but also the aims of effective control and distribution of the lithium-liquid flow cell combined energy storage power station and aims of effective control and distribution of the lithium-flow flow joint energy storage power station real-time power can be achieved.

Abstract: The present invention provides a method for detecting the anti-island protection performance of an inverter. An RLC circuit is serially connected between the inverter and a grid connection switch, the resonant frequency of the RLC load is set as three different numerical values for enabling the same to present resistance, capacitance and inductance, and a time value from the disconnection of the grid connection switch to the operation stop of the inverter under detection is recorded after a fundamental current value of the grid connection switch is set to a different value each time; and weighted calculation is performed on the time value to obtain a test result and grade evaluation of the anti-island protection ability of the inverter.

Abstract: The present application discloses a method for optimized design of an independent micro-grid system, the independent micro-grid system comprising diesel generators, wind powered generators, a photovoltaic array, and an energy storage battery, the optimization method referring specifically to a multi-objective optimization design model based on the independent micro-grid system. In terms of the optimization planning design model, the method takes into account a combined start-up mode for a plurality of diesel generators and a control strategy for coordinating between the energy storage battery and the diesel generators, such that the usage rate of renewable energy in the independent micro-grid is higher, and operations more economical and environmentally friendly. Regarding the stability of the system optimization planning design model, the method takes into account the reserve capacity needed for stability of the independent micro-grid.

Abstract: A sensor and method for identifying a downed power transmission conductor or structure is disclosed. The method includes the steps of securing a sensor to a power transmission conductor or structure, using the sensor to measure inclination of the power transmission conductor or structure, comparing the measured inclination to a set threshold, and alerting a utility if the measured inclination exceeds the set threshold.

Abstract: A multi-functional automatic switching circuit for direct current ice melting and a switching method thereof are provided. The automatic switching circuit comprises at least one sub-switching circuit. The sub-switching circuit comprises a six-pulse current converter (R) with no saturable reactor, six reactors (L1a, L1b, L1c, L2a, L2b, and L2c), three three-phase knife switches (Sac1, Sac2, and Sac3), and five single-phase knife switches (SV1, SV2, SV3, SV4, and SV5). The sub-switching circuits in series connection or parallel connection, four direct current side switching knife switches (Sdc1, Sdc2, Sdc3, and Sdc4), an isolation knife switch (K), a breaker (QF) and a control and protection system (CP) may form an automatic switching circuit for six-pulse or twelve-pulse direct current ice melting.

Abstract: A sensor apparatus for detecting leakage current in a post-type insulator of an electrical power system includes: a sensor unit having a housing, the sensor unit including: a sensor assembly operable to generate an analog signal proportional to a received leakage current; an electronics module operable to covert the analog signal to a digital value; and a communications system operable to wirelessly transmit the digital value to an external receiver; a collection band adapted to be connected to an exterior surface of the insulator; and a transfer lead interconnecting the sensor assembly and the collection band, the transfer lead operable to transfer leakage current from the insulator from the collection band to the sensor assembly.

Abstract: A low-frequency band suppression enhanced anti-reversal power system stabilizer is presented by the invention. Currently the widely used PSS2B power system stabilizer needs lead elements above Order 2 to meet the phase compensation requirement of DC blocking signal of active power, thus quickly increasing high-frequency band gain, restricting allowable total setting gain of PSS, limiting low-band gain and reducing low-frequency band suppression ability of power system stabilizer. The invention will add generator speed signal ? (which is treated by DC blocking element and corrected by parallel proportional differential PD) and active power signal Pe (which is treated by DC blocking element and gained by gain factor Ks3) to get equivalent synthetic mechanical power of power system stabilizer.

Abstract: smart power distribution system and a method to progressively dispatch the power is described. The method steps are all automatic and self-adaptive. The method can be executed in an unattended manner to automatically correlate real time data vs. historical data, planning data vs. operation data. Based on a long cycle periodical variation and short-term random variations in load, and taking into account the temporary load power supply and maintenance needs, a multi-stage progressive multiple time scales optimal dispatching method is developed, including the distributed power, micro-grids, energy storage devices, electric vehicles charge-discharge facility and other elements of the Intelligent power distribution systems, to achieve coordinated operation of the network, power, load resources to ensure a continuous safe and reliable smart power distribution system operated at high quality and efficiency.

Abstract: A system for staring a large-scale power load in a micro grid comprises a PCC grid connection switch, a micro grid alternating-current bus, an active power filter (APF), an energy storage inverter, an energy storage battery, a current-limiting resistor R, contactors K1-K3, a time relay KT, a power supply relay board, a micro grid maser control system, a frequency converter rectifying circuit, a frequency converter filter circuit, and a frequency converter inverter circuit. There are the advantages: an output torque of a power load can be effectively improved by using a variable frequency starting apparatus, and a starting current is also small; the provided method can effectively reduce a harmonic current when a variable frequency starting apparatus starts a power load, the phenomenon that two power sources supply power on a direct-current side of the variable frequency starting apparatus at the same time is avoided, thereby improving the stability and the economy of a micro grid.

Abstract: The invention provides a global optimization and dispatching method based on time scales. The method uses a target value system and a dispatch model. The global optimization and dispatching method takes input from the results from a variety of subtopics. The methods provide adjustment and optimization in accordance with the time scales that are given in the sub goal of each sub topic: long-term, mid-long-term, short-term, ultra short term and real time optimization. Smart distribution grid can improve operational efficiency, integrated application of new elements in the distribution network of distribution energy network, micro grid, energy storage device and non-linear loads. This invention is fully adapted to the smart grid trends, with a good prospective.

Abstract: An apparatus and method for continuously monitoring substation disconnects and transmission line switches to detect improper closing of the disconnects or switches is disclosed. The method includes the step of providing an apparatus adapted to measure, process, and transmit data associated with a disconnect or switch. The method further includes the steps of positioning the apparatus on or in close proximity to the disconnect or switch, using the apparatus to collect data of the disconnect or switch and processing the data for transmission to a remote receiver, and transmitting the processed data to a remote receiver.

Abstract: A cleaner and method for maintaining bearings, bushings, linkage pins and chains used in various types of machinery, including industrial machinery is disclosed. The cleaner is effective to rejuvenate spent grease and includes a polar fraction, a miscible non-polar fraction, and a non-ionic surface activating agent.

Abstract: The invention provides a method for overcoming the influence of out-flowing current on bus differential protection. The method comprises the following steps: acquiring and processing branch current signals; selecting a fault bus, and determining the branch current with maximum amplitude from branches connected with the fault bus; calculating differential current and restraint current of a large differential element, and determining whether the large differential element acts. The method for overcoming the influence of out-flowing current on bus differential protection does not need to reduce the braking coefficient during splitting operation in a two-bus connecting mode, can adaptively improve the sensitivity of bus differential protection under an internal fault in the presence of out-flowing current, and simultaneously ensures the reliability under an external fault.

Abstract: A system configured to provide cathodic protection to buried and/or submerged metal components and/or structures, such as pipes is disclosed. The system includes a cathodic protection apparatus having at least one upright support and a plurality of sacrificial anodes secured to the at least one upright support in a vertical orientation to provide variable cathodic protection to the metallic structures.

Abstract: Disclosed are a method for searching a cross-regional power supply area based on a common information model (CIM) and a system thereof. In the method, a hash function is first created according to a size of a power grid in which a power source is located; identification numbers of all devices in the power grid are mapped to a discrete hash table according to the hash function, and a collision is solved by using separate chaining; and a hash topological graph of the power grid is formed by using the discrete hash table; and a power supply area of a designated device is searched by using the hash topological graph. According to the present invention, devices in a power supply area are located rapidly and accurately by creating a discrete hash table for all device resources, so that the amount of computation is greatly reduced, and the efficiency of searching the power supply area is significantly improved.