277results about How to "Power balance" patented technology

A renewable energy resource management system manages a delivery of a power requirement from a multi-resource offshore renewable energy installation to an intelligent power distribution network. The installation includes multiple renewable energy resource components and is capable of variably and independently generating power from each to microgrids comprising the intelligent power distribution network so that the entire power requirement is satisfied from renewable energy resources. An electricity grid infrastructure is also disclosed in which power production is balanced with power consumption so that power storage requirements are minimized.

A renewable energy-based electricity grid infrastructure utilizes distributed data analytics to enable modeling and delivery of an appropriate, time-sensitive, dynamic demand response from multiple renewable energy components to an intelligent power distribution network. Data processing resources are identified and aggregated within a distributed computing infrastructure to provide dynamic demand response as a service of a dedicated grid data analytics module. Aggregation of processing resources for grid data analytics also enables the electricity grid infrastructure to virtually, optimally and adaptively make decisions about power production, distribution, and consumption so that a demand response is a moduled service of the electricity grid infrastructure, and enables distributed energy generation from multiple renewable energy resources that is responsive to various types of grid demand situations, such as customer demand, direct current-specific demand, and security issues, and so that power production is substantially balanced with power consumption.

A power transmission system manages a delivery of a power requirement from multiple renewable energy resource components to an intelligent power distribution network. The transmission system includes components capable of variably and independently generating power from the multiple renewable energy resource components to provide a dynamic demand response to a power requirement to one or more microgrids comprising the intelligent power distribution network so that the power requirement is entirely satisfied from multiple renewable energy resources from a common location. The transmission system enables distributed energy generation from the multiple renewable energy resources that is responsive to various types of grid demand situations, such as customer demand, direct current-specific demand, and security issues, and so that power production is substantially balanced with power consumption.

The invention discloses an energy control method for an independent photovoltaic hybrid energy storage system. The hybrid energy storage system comprises a storage battery, a super capacitor, a photovoltaic power generation unit, a DC bus and a DC load. The storage battery and the super capacitor are connected in parallel with the DC bus through respective bidirectional DC/DC converters. The photovoltaic power generation unit is connected to the DC bus through a BOOST converter. After data acquisition, an energy control processor calculates the power that should be borne by the hybrid energy storage system, and then the power passes through a first-order low-pass filter. According to limit control methods of different sections, the hybrid energy storage system, under different control conditions, achieves power distribution to the storage battery and the super capacitor, maintains the stability of the DC bus, stabilizes photovoltaic output power fluctuation, maintains in-system power balance, optimizes the work of energy storage equipment to a certain extent, and prolongs the service life of the energy storage equipment.

A renewable energy resource management system manages a delivery of a power requirement from a multi-resource offshore renewable energy installation to an intelligent power distribution network. The installation includes multiple renewable energy resource components and is capable of variably and independently generating power from each to microgrids comprising the intelligent power distribution network so that the entire power requirement is satisfied from renewable energy resources. An electricity grid infrastructure is also disclosed in which power production is balanced with power consumption so that power storage requirements are minimized.

A renewable energy resource management system manages a delivery of a power requirement from a multi-resource offshore renewable energy installation to an intelligent power distribution network. The installation includes multiple renewable energy resource components and is capable of variably and independently generating power from each to microgrids comprising the intelligent power distribution network so that the entire power requirement is satisfied from renewable energy resources. An electricity grid infrastructure is also disclosed in which power production is balanced with power consumption so that power storage requirements are minimized.

The invention relates to a multi-sub microgrid-contained mixed microgrid system and a control method thereof. The mixed microgrid system comprises a photovoltaic subsystem, an energy storage subsystem, a direct-current bus, a DC/AC converter and an alternating-current subsystem. The control method comprises the following steps: controlling running modes of the photovoltaic subsystem and the energy storage subsystem according a power grid instruction; controlling the running mode of the photovoltaic subsystem by using a perturbation observation method-based photovoltaic generation maximum power tracking method; and controlling the running mode of the energy storage subsystem by using a method of combination of dual-closed loop control and phase-shift control. Compared with the prior art, the provided system and the method have the advantages of electrical isolation realization, high security, and stable bus voltage and the like.

The invention discloses an automatic intelligent power distribution system and a power distribution method. The power distribution system comprises a power distribution executing unit, and the power distribution executing unit receives a power distribution command from a power distribution monitoring terminal and gates a corresponding phase line on a three-phase power transmission line to a single-phase power supply line on an output side of the power distribution executing unit to achieve intelligent power distribution. According to the automatic intelligent power distribution system, low-voltage three-phase disequilibrium distribution on an input side of a single-phase user is achieved through the power distribution executing unit on an input side of an electricity meter of the single-phase user, the power distribution monitoring terminal receives the electrical load information of each single-phase user in a wireless or power line carrier communication mode, and a basis is provided for the equilibrium distribution of single-phase user quantity on each phase line of the three-phase power transmission line on the whole; the power distribution monitoring terminal sends the power distribution command to the power distribution executing unit and the power distribution executing unit enables each single-phase user to be connected to a corresponding power supply phase line in a grouping mode, and therefore equilibrium power distribution is achieved for single-phase users on a low-voltage side.

The invention discloses a voltage and power balance control method for a modular power electric transformer. The power electric transformer to which the method is applied to comprises an input stage, an isolation stage and an output stage; the input stage adopts common duty ratio control based on single phase dp decoupling, so that stable control of high voltage side direct current voltage and flexible adjustment of sine and power factors of input current are achieved; the isolation stage adopts a voltage power double loop control strategy without a current sensor, the output voltage outer loop adjustment generates a unified reference value of each power inner loop, and the adjustment of each power inner loop generates a phase shifting angle of each module of the isolation stage; and two types of control strategies of the input stage and the isolation stage act synergistically, so that voltage and power balance of each module of the power electric transformer is achieved.

The invention relates to an energy control method of an urban rail super capacitor storage system. The method comprises the following steps that: a direct-current power supply network voltage Udc and a super capacitor module group terminal voltage Usc are collected respectively and an output branch current Isc of the super capacitor module group is connected within each control period; a charging-discharging threshold calculation module outputs a charging threshold value Uchar and a discharging threshold value Udis in real time based on the super capacitor module group terminal voltage Usc within each control period; and according to a relation between the charging threshold value, the discharging threshold value, and the direct-current power supply network voltage Udc, a current control period of an urban rail super capacitor storage system is determined to be in a charging state, discharging state or a standby state. According to the energy control method provided by the invention, multiple sets of urban rail super capacitor storage systems can work in a coordinated mode and thus the urban rail super capacitor storage systems can absorb brake energy of the train fully and effectively, thereby improving the energy utilization efficiency of the urban rail power supply system. Moreover, fluctuation of the direct-current side voltage of the power supply system can be inhibited.

The invention discloses a low-voltage crossing method of two-stage type photovoltaic grid connected system of variable power tracking path, which belongs to the field of new energy electric power system and micro power grid technology. Under the prerequisite that the original configuration of a two-stage three phase photovoltaic grid connected system is not changed and no auxiliary device is added, the power tracking path can be adjusted through the feed-forward control of the falling amplitude of voltage, the voltage at the photovoltaic cell end can be changed in a real-time manner, and the output of the photovoltaic cell power can be rapidly and effectively controlled, and the balance of power at two sides of an inverter can be realized. Through the cooperative control with a grid connected inverter, it can be guaranteed that under the prerequisite that the grid connected output of current of the inverter is not out of limit, active power and reactive power can be provided for the power grid as more as possible, the recovery of power grid voltage can be supported to the most extent, and the zero-voltage crossing of the photovoltaic grid connected system can be realized. Comparedwith the conventional control method, the invention is advantageous in that no additional device is required; safe and stable running of the system can be realized; the cost of the photovoltaic powergeneration system can be reduced, and practicality is better.

In a renewable energy-based electricity grid infrastructure, distributed data analytics enable modeling and delivery of an appropriate, time-sensitive, dynamic demand response from multiple renewable energy resource components to an intelligent power distribution network. Distributed data analytics also enable the electricity grid infrastructure to virtually, optimally and adaptively make decisions about power production, distribution, and consumption so that a demand response is a dynamic reaction across the electricity grid infrastructure in a distributed energy generation from multiple renewable energy resources responsive to various types of grid demand situations, such as customer demand, direct current-specific demand, and security issues, and so that power production is substantially balanced with power consumption.

The invention discloses a power equilibrium control method for reducing DC voltage fluctuation of a cascaded H-bridge inverter, and aims to solve the problem that power generation quantity is reduced caused by relatively large DC-side voltage fluctuation. The power equilibrium control method comprises the following steps of controlling a total DC-side voltage to achieve tracking of a maximum power point voltage of the DC-side voltage of each H-bridge unit and obtain an active current instruction value of a system; controlling decoupling of a network-side current, where independent control on an active current and reactive current can be achieved, and meanwhile, a total modulation wave voltage of the inverter is generated; and performing power equilibrium control between units, an accurate on-off state of each H-bridge unit is determined and power equilibrium control of each H-bridge unit and maximum power tracking of each H-bridge unit are achieved by sequencing an error of the DC-side voltage of each H-bridge unit. By the method, various working conditions can be adapted, stable running of the cascaded H-bridge photovoltaic inverter within a relatively large range can be achieved, moreover, the DC-side voltage fluctuation can be reduced, and the power generation quantity of the system is improved.

The invention provides an in-phase SOC (state of charge) balancing method of an MMC battery energy storage system. The energy storage system adopts carrier phase-shift modulation. The method includes collecting SOC information and charging and discharging states of energy storage batteries, namely collecting the SOC information of each power module energy storage battery and the charging and discharging states of the system at the moment through a battery management system; adjusting carrier amplitude, namely adjusting forward and backward access time ratio of corresponding power modules according to different states of a PCS system and the size of SOC of each power module energy storage battery in phase. The objective of in-phase energy storage battery SOC power balancing is realized by taking the MMC battery energy storage system as an object, collecting battery SOC and controlling carrier amplitude.

The invention discloses a modular H bridge cascade multi-level power electronic transformer control system, comprising a high-voltage rectifier circuit unit composed of a plurality of cascade single-phase H bridge rectifiers, an isolated converter circuit unit composed of a plurality of parallel high-frequency DC/DC isolated converters correspondingly connected with the single-phase H bridge rectifiers, a low-voltage inverter circuit unit connected to the output end of the isolated converter circuit unit, as well as a high-voltage side controller, an isolation level controller and a low-voltage inverter controller which are separately used for controlling the above units, wherein the controllers independently control the high-voltage rectifier circuit unit, each high-frequency DC/DC isolated converter and the low-voltage inverter circuit unit by adopting a high-voltage rectifier control module, an isolated double-loop control module and a double-loop inverter control module separately. The system simplifies the design of the controllers, and the stability and the reliability of the transformer control system are improved.

The invention discloses an economic dispatching method and system for a microgrid based on distributed network control. The method comprises S1: deriving a theoretical optimal output formula of controllable distributed generation DG under a constraint condition according to an economic dispatching model; S2: constructing a communication network according to a microgrid double-layer control model comprising a lower microgrid and an upper communication network; S3: designing a weight matrix according to the upper communication network and obtaining a distributed control law according to the weight matrix; S4: calculating a set value according to the distributed control law, and adjusting the output of the controllable distributed generation DG according to the calculated set value, thereby realizing economic optimal dispatching of the microgrid. The method and the system have the advantages that the total power generation cost of the microgrid can be minimized by realizing equal tiny increase rate of all controllable DGs; convenience is provided for an algorithm design by designing the weight matrix; and the system power balance can be ensured during the iteration process.

The invention discloses an optimization control method for a Boost PFC comprising an active energy storage unit, and belongs to the field of AC-DC power conversion. The invention aims at a problem of reference distortion, caused by the condition that an output voltage of a rectifier bridge is taken as a sine reference, in a conventional Boost PFC mean current control method. The method comprises the steps: converting an input sine voltage into a square signal through a square wave conditioning circuit, enabling a digital controller to capture the rising and falling edges of the square signal, and generating a pure sine signal as a sine reference through an anti-error capturing phase-locking algorithm, so as to improve the reference distortion; deducing an input feedforward and load feedforward algorithm on the basis that a sine reference control method is generated, so as to improve the capability of an output voltage in resisting input and load disturbance and increase the tangential velocity of a light load tangential algorithm. The method achieves the deduction of an input current of the active energy storage unit as the reference through the generated sine signal and the output current, and saves a band-pass filter circuit which samples the input current reference of the active energy storage unit. Moreover, the method improves the power density and efficiency of a converter.

A motor-gear unit, having an eccentric wheel gear, driven by a rotary drive (3), which eccentric wheel gear has an eccentric element (8), an eccentric wheel (10) rotatably supported on the eccentric element, and a driver (15), and the driver (15) cooperates with the eccentric wheel (10) by intermittent meshing, further having at least one guide bolt (22), which cooperates with the eccentric wheel (10) and both assures the eccentric motion of the eccentric wheel (10) and prevents an undesired rotation of the eccentric wheel 10. It is proposed that the eccentric wheel gear is disposed in a free installation space of the rotary drive (3).

The invention discloses a thermal power unit power prediction control system for ensuring the safety and stability of a sending-end electric grid. The thermal power unit power prediction control system comprises a high-frequency emergency state and prediction unit (1), a speed regulator prediction control unit (2) and a boiler prediction control unit (3), wherein the high-frequency emergency state and prediction unit (1) is electrically connected with the speed regulator prediction control unit (2) and the boiler prediction control unit (3); the speed regulator prediction control unit (2) is electrically connected with a servo of a speed regulating mechanism; and the boiler prediction control unit (3) is electrically connected with a boiler and an auxiliary machinery. According to the invention, when the sending-end electric grid is split, the power naturally distributed to a unit by the sending-end electric grid is measured, unit prediction power setting for keeping isolated grid balance and equitable distribution is obtained through conversion, fast and accurate control regulation is carried out through a unit prediction control method on a steam turbine and the boiler, so that the dynamic energy balance among the boiler, the steam turbine and the sending-end electric grid is effectively ensured, the problem of oscillation of OPC (Overspeed Protection Control) is solved, and the high-frequency stable level of the sending-end electric grid and the safety of the unit are greatly enhanced.