1046 results about "Electricity system" patented technology

Enclosed is an active and reactive coordination control method for permanent-magnet direct-driven wind turbines in the low-voltage ride-through process. Two different control strategies are employed for a grid side converter according to amplitude change of power grid voltage: when the power grid voltage is in a normal state, the grid side converter is in an active-priority maximum power tracing control mode so that the wind turbines capture wind energy to the maximum extent; when the power grid voltage is beyond the normal range, the grid side converter is in an active priority control mode so that the dynamic reactive current which is injected into an electricity system meets the requirements of grid combining. An engine side converter is in a direct-current voltage control mode based on rotor energy storage, power unbalance of the direct-current side of the engine side converter is relieved and the direct-current voltage is stabilized by utilizing the self rotating speed of the permanent-magnet direct-driven wind turbines and the change of the kinetic energy. The active and reactive coordination control for the wind turbines before or after the sudden change of the power grid voltage is realized according to the amplitude change of the power grid voltage, the fluctuation of the direct-current bus voltage is restrained by releasing or storing the rotor kinetic energy, so that the low-voltage ride-through capability of the permanent-magnet direct-driven wind turbines is improved, reactive power support is rapidly and accurately provided for the power grid, and certain support is given to restoration of the power grid voltage.

A waste heat recovery system, method and device executes a thermodynamic cycle using a working fluid in a working fluid circuit which has a high pressure side and a low pressure side. Components of the system in the working fluid circuit include a waste heat exchanger in thermal communication with a waste heat source also connected to the working fluid circuit, whereby thermal energy is transferred from the waste heat source to the working fluid in the working fluid circuit, an expander located between the high pressure side and the low pressure side of the working fluid circuit, the expander operative to convert a pressure/enthalpy drop in the working fluid to mechanical energy, a recuperator in the working fluid circuit operative to transfer thermal energy between the high pressure side and the low pressure side of the working fluid circuit, a cooler in thermal communication with the low pressure side of the working fluid circuit operative to control temperature of the working fluid in the low side of the working fluid circuit, a pump in the working fluid circuit and connected to the low pressure side and to the high pressure side of the working fluid circuit and operative to move the working fluid through the working fluid circuit, and a mass management system connected to the working fluid circuit, the mass management system, method and device having a working fluid vessel connected to the low pressure side of the working fluid circuit and configured to passively control an amount of working fluid mass in the working fluid circuit.

There is provided a battery including a positive electrode, a negative electrode, a separator at least including a porous film, and an electrolyte. The positive electrode includes a positive electrode current collector having a pair of surfaces, and a positive electrode active material layer provided on each of the surfaces of the positive electrode current collector. The positive electrode active material layer contains a positive electrode active material. The positive electrode active material layer has an area density S [mg/cm2] more than or equal to 30 mg/cm2. The porous film included in the separator has a porosity ε [%] and an air permeability t [sec/100 cc] which satisfy a predetermined formula.

The invention discloses a method for estimating a state of health (SOH) and a state of charge (SOC) of a storage battery. The method is applied to a backup power system. The method comprises the following steps of: estimating the SOH and the SOC of the storage battery by using two branches simultaneously; comparing deviation of estimated values of the two branches; and selecting and determining the estimated values. In the method, a backup battery pack is not needed and measurement can be finished on line; quantitative measurement can be realized and the accuracy is high; and during measurement, complicated equipment is not needed, so that the cost is reduced.

The present invention relates to a tray comprising: a) a base panel having two opposite edges adapted for sliding within grooves of a structure; b) a pair of electrical contacts located on the two opposite edges of the base adapted to conduct electricity; c) a battery recharging system adapted to provide one or more electromagnetic fields capable of transferring an electrical charge to a properly equipped electrical device having a rechargeable battery or a connection for a portable electronic device adapted to connect the portable electronic device to the power system of a host and/or other electronic systems of the host; d) means for connecting the pair of electrical contacts to the battery recharging system or to the connection to the portable electronic device; e) one or more display panels providing a surface for resting one or more rechargeable portable electric devices upon, such panels adapted to allow one or more users of portable electronic device to view one or more displays of the portable electronic devices; f) panels for connecting the base panel and one or more display panels and for enclosing the tray. The tray is adapted for use in a host system which supplies power to the tray. In a preferred embodiment, the host system is or is utilized in a vehicle.

The invention discloses a unit combination method for resolving and considering wind power volatility. Compared with the existing unit combination method, the method has the benefits that by applying an interval linear programming theory, the system security can stability can be theoretically ensured within a wind power output fluctuation scope, and the economy of the system is improved on the premise of safety; and under the realistic background that wind power and other new energy resources are largely introduced, the ability of the power system to answer the wind power volatility can be effectively improved, and the system safety and the stability are improved.

The present invention discloses parameter regulating method of non-linear electricity system stabilizer based on frequency domain test and pertains to the technical field of stability control of electric power system. The present invention is characterized in that: test the non-frequency-compensation linear property curves and test the phase angle under different frequency points in the low frequency vibrating range of 0.2 to 2.0Hz from the output point of the stabilizer to the voltage of the generator after the working condition of tested machine unit is fixed; then calculate the lead and lag angle a 1 of the linear part of the output signals of the stabilizer under different frequencies, added with phase angle that has corresponding frequency property, and then decide whether surpass the lead and lag range relative with Delta Omega axle prescribed by national standard; if not surpass, the feedback factor k1, k2 and k3 of the linear part can be calculated out; then the damping coefficient C1 and the gain coefficient C2 can be decided with critical amplification times method and load phase step method. The present invention is easy to be comprehended by commissioning operators and is easy to be populated.

The invention belongs to the technical field of electric power systems and particularly relates to a method for electric vehicle load prediction based on an efficiency maximization principle. First a space-time distribution model of electric vehicles is established based on a trip chain, information such as initial departure time, driving destination, driving distance and stopping time is analyzed, and charging space-time distribution of the electric vehicles is obtained. Charging stations most favorable for users are selected based on the efficiency maximization principle to charge the electric vehicles, and finally space-time distribution of electric vehicle charging loads is given. On the basis of the fact that the electric vehicle load prediction by previous scholars is only confined to the time level and the regional level, the method for electric vehicle load prediction based on the efficiency maximization principle is provided, and the load prediction can be detailed to the charging stations.

In some embodiments, the present invention includes the use of one or more electric power supply system, or systems, and the electric vehicle, or vehicles, connected thereto, to provide load-based utility grid frequency regulation by varying the amount of power drawn by the vehicle or vehicles.

A storage assembly for use in a passenger compartment of a vehicle provides power to an electronic device from a vehicle power system. The storage assembly includes a storage bin having an exterior surface, an opening, and a storage space accessible through the opening. The storage assembly also includes a door having an outer surface which is pivotally coupled to the storage bin. A retractable cord is attached to a detachable member which is releasably attached to the storage bin. The retractable cord includes a first end having a first connector which is configured to connect the vehicle power system and a second end having a second connector configured to connect to the electronic device. A notch is formed in the housing adjacent the opening. The notch allows the second connector to extend beyond the exterior surface of the housing when a door is in the closed position.

The invention discloses a multi-target dynamic scheduling method for a wind storage hydrothermal power system based on multi-source complementation, and the method comprises the following steps: 1, building a multi-target dynamic economical scheduling model: 1.1, building four optimization targets: take the minimum thermal power coal consumption, the minimum thermal power output adjustment volume, the maximum thermal power generation and the minimum load fluctuation after the thermal power is inputted to a power grid; 1.2, determining the constraint conditions of the four optimization targets; 2, carrying out the weighting and conversion of the four optimization targets, and obtaining a target function F of the multi-target dynamic economical scheduling model; 3, combining with the target function F, and solving the multi-target dynamic economical scheduling model through employing the improved plant growth simulation algorithm. According to the invention, the method gives full consideration to the economical performance and stability of thermal power operation, the utilization rate of the wind power and hydropower and the adjustment effect of a pumped storage power station, and guarantees the economical performance and stability of operation of the thermal power generating unit while promoting the consumption of the wind power.

The invention provides an electric vehicle charging guidance method considering road-network-vehicle, which considers the charging demand difference of different types of electric vehicles, performs optimized guidance scheduling on the electric vehicles in slow charging and fast charging modes from two aspects of day-ahead and real-time. The method comprises the following steps: establishing an electrical traffic cooperative control architecture; formulating a charging station selection and navigation strategy; formulating a time-sharing and zoning electricity price to guide quick charging; and establishing a double-layer optimization scheduling model to guide slow charging. According to the method, on the premise that the safety and economy of a power distribution system are guaranteed, the satisfaction degree of power consumers is considered, and different charging requirements, time and space and other factors are considered to research the guide strategy and operation mode of the electric vehicle. Analysis of the charging station and system load conditions before and after optimization shows that the method enables the system load to be gentler than that in a free charging mode, plays a role in peak clipping and valley filling to a certain extent, and improves the operation safety and economy of a power system.

The invention discloses a wind power eliminating method considering the interruptible load and the day-ahead hour electricity price. A day-ahead hour electricity price optimization and an interruptible load under a wind power uncertainty condition are established to participate in a standby power system dispatching two-layer planning model containing wind power, and the outer layer is a day-aheadhour electricity price optimization model, and the inner layer is a daily electric power system dispatching model. A random scheduling method is adopted, and the optimal day-ahead hour electricity price, the wind electricity eliminating and electricity system economic dispatching in a plurality of scenes can be realized. According to the invention, the non-flexibility of the single electricity price and the peak-valley time-sharing electricity price is overcome, and the system abandoning amount is reduced. The power generation efficiency of the power grid is improved, the peak shaving capacityof the power grid is improved, the power generation cost of the thermal power generation is reduced, and the benefit of the user is increased.

The invention relates to a power scheduling operation method, in particular to a wind-fire-water co-scheduling method on the basis of a multi-agent system. The method solves the problem that a conventional power scheduling operation method cannot meet the requirement on the large-scale wind power grid-connected operation. The wind-fire-water co-scheduling method on the basis of the multi-agent system is implemented by adopting the following steps of: 1, constructing a wind-fire-water co-scheduling model on the basis of the multi-agent in a scheduling Agent; 2, acquiring predicted data of a load demand in a power system by a load Agent in the power system; 3, sending acquired basic data and real-time data into the wind-fire-water co-scheduling model on the basis of the multi-agent by each thermal power Agent; and 4, issuing and executing a scheduling command by each thermal power Agent and a hydroelectric Agent. The wind-fire-water co-scheduling method is suitable for large-scale wind power grid-connected operation scheduling.

An apparatus and method for operating a fuel cell power system utilizing a low voltage power source and system power to power an airmover. The fuel cell power system uses a low voltage power source to power the airmover during start-up and transitions to using system power to power the airmover as the fuel cell stack increases its voltage output. During a shutdown operation the fuel cell power system transitions from using system power to using the low voltage power source to power the airmover enabling a purging operation to be performed. A controller coordinates the operation of the airmover between using the low voltage power source and using electrical power produced by the fuel cell stack to power the airmover.

A method is proposed for real-time economic dispatch in power system operation, especially in systems that include renewable power sources that may cause heavy deviations from a generation schedule due to their uncertain outputs. According to the method an optimal generation schedule is obtained based on forecasted load data. This schedule has to be adjusted if the actual load and renewable energy source outputs unexpectedly deviate from the forecasted value. An algorithm employed in the method is capable of dictating generation adjustments which minimize total generation costs. The algorithm is a modification of the base point and participation factor method. It differs from existing methods in that a precise model of transmission losses is adopted in the algorithm to achieve higher accuracy in optimization. The proposed method also has significant advantage in execution speed so that it is suitable for real-time operation.