The integration of renewable energy, such as PV and wind power, has exerted great impacts on the power system with its rapid development. If corresponding energy storage is configured, could be able to hold a higher proportion energy. Focusing application for output fluctuation mitigation this paper first analyses reason from four aspects frequency, unit ramp, low frequency oscillation cascading failure. In addition, rate standard grid-connected type topology are introduced. Then summary...

The rapid development of renewable energy sources such as wind power has brought great challenges to the grid. Wind penetration can be improved by using hybrid storage (ES) mitigate fluctuation. We studied strategy smoothing fluctuation and ES distribution. Firstly, an effective control extracted comparing constant-time low-pass filtering (CLF), variable-time (VLF), wavelet packet decomposition (WPD), empirical mode (EMD) model predictive algorithms with rate constraints identical...

In order to improve the automatic generation control (AGC) performance of thermal generators, this paper presents a stochastic model predictive (SMPC) approach for battery/flywheel hybrid energy storage system (HESS) distribute power. The combines an adaptive Markov chain power demand prediction HESS, scenario tree and strategy. To develop effective deal with randomness generator in response AGC command, is used describe HESS demand, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Due to limitations of topology, the series architecture electric energy router (SA-EER) for low-voltage distribution network (LVDN) has disadvantages that transmission range is limited 100% and reactive powers are unable operate flexibly. For this reason, a new type EER with series-parallel (SPA-EER) constructed in paper, it can break through above SA-EER. In addition architecture, two-degree-of-freedom power flow flexible control strategy (TDF-PFFCS) proposed further support realization...

Distributed generation is a vital component of the national economic sustainable development strategy and environmental protection, also inevitable way to optimize energy structure promote diversification. The power generated by renewable unstable, which easily causes voltage frequency fluctuations quality problems. An adaptive online adjustment particle swarm optimization (AOA-PSO) algorithm for system proposed solve technical issues large-scale wind light abandonment. Firstly, linear...

In order to support the perception and defense of operation risk medium low voltage distribution system, it is crucial conduct data mining on time series generated by system learn anomalous patterns, carry out accurate timely anomaly detection for discovery conditions early alerting. And edge computing has been widely used in processing Internet Things (IoT) data. The key challenge univariate how model complex nonlinear dependence. However, most previous works only short-term dependence,...

The uncertainty of supply and demand have different characteristics, which can adversely affect the stable operation microgrid. This paper presents a multi-time scale scheduling strategy, mainly consists day-ahead layer intraday adjustment layer. In layer, Monte Carlo method response are used to deal with both demand, stochastic optimal model is established by considering in first stage, unit commitment decisions derived optimization framework achieve minimum operating cost. second economic...

This paper describes the basic principles of flywheel energy storage technology and UPS power supply vehicle structure principle. The Application state in Beijing grid protection is analysed by portable multi-channel synchronous quality tester. test results show Flywheel has good performance, which can guarantee continuity vital user important load, meet requirements users special period enhance level service supply. applications data provide a reference for emergency users, so strong...

The circulating current is one of the important issues for parallel converters. It affects system stable operation and degrades power quality. In order to reduce converter harmonic pollution grid, a new suppression strategy proposed source without any communication line. This able realize sharing between modules by changing external characteristics thus suppress among control adopts DC-side droop AC-side virtual impedance control. used generate reference voltage each module, while...

There is a large amount of controllable loads in the microgrid. They can be described as virtual energy storage to participate microgrid tie-line power fluctuation mitigation. Firstly, order meet grid-connected requirement, wavelet packet decomposition algorithm used smooth fluctuation. Furthermore, prevent overcharge and overdischarge battery or storage, allocation between two types implemented equally based on concept energy. In addition, fuzzy control strategy applied revise its SOC (i.e....

Droop control is an effective method for the parallel operation of voltage sources without any communication among modules. However, in low-voltage microgrids (MGs) line impedance predominantly resistive that causes active and reactive power can be no longer decoupling, then finally influences sharing accuracy inverters. It has been demonstrated adding a virtual output (VOI) loops regulate Total Equivalent Impedance (TEI) between module common bus to inductive, thus improves accuracy. this...

A new perspective of impedance matching is proposed to study the power flow operation three‐phase four‐wire (3P4W) unified quality conditioner (UPQC) system. Specifically, UPQC system equivalent an adjustable network, when external conditions change, such as grid voltage sag/swell and unbalanced loads, node impedances in network will be dynamically matched. On one hand, three nodes series converter (SC) matched positive or negative with change voltages, which means that SC operates a...

Traditional schemes of UPQC and OPEN are proposed in literature to solve both the voltage quality problem load current grid. However, traditional is not flexible when configured compensate an industrial park if all loads sensitive. The previously scheme has advantages that communication coordination required. To above problems, a new topology this paper. analyzed detail control corresponding power flows given. Further application also given only achieve function conventional UPQC, but...

This paper reviews the current research status of multi-energy coordinated evaluation for energy Internet. Taking optimization effect wind energy, solar and other sources into consideration, 17 indexes, such as substitution coefficient cold heat power, ratio rate storage ratio, were designed from five aspects, including acceptance renewable complementary alternative benefits, peak valley difference, degree equipment utilization user needs. At same time, this article attaches importance to...

In order to ensure the reliable power supply of local load in micro-grid (MG), a seamless switching control technology (SSCT) suitable for grid-connected converter (GCC) is proposed. This includes silicon-controlled rectifiers (SCR) forced shutdown strategy (SCR-FSCS) and three-loop (TLCS). The SCR-SSCT adjusts voltage real time form back at inductor, which greatly reduces SCR ensures reliability supply. TLCS can easily realize between current source mode GCC. An experimental platform...

The operation of micro-grid based renewable energy usually considers efficiency and economy in comprehensive. control strategy on master micro-source (MS) constant voltage frequency (CVCF) networking is introduced. established by the MS, slave MS operated maximum power point tracking mode, order to achieved efficient economic operation. For improving function each micro-grid, a multi-functional convertor proposed. According this strategy, has forming switching public grid seamlessly, while...

Custom power devices are a set of designed to protect customers' loads from line disturbances. One class custom is the series-connected device (SC), such as dynamic voltage restorer (DVR) and series active filter (SAPF). Recently, downstream fault limiting function have been proposed integrated in some literatures an add-on feature, which can limit flow large currents, therefore restore point common coupling (PCC) well themselves. Though it sounds straightforward, there many difficulties...

IGBT modules have been widely used in many fields such as renewable energy generation and rail transportation because of their excellent switching performance. However, the application reliability is affected by factors, among which humidity one most serious factors threatening health modules. In high applications, moisture tends to penetrate inside module, lead corrosion degradation module. this paper, finite element simulation reveals that bonding line solder layer are weak points module...

With many branch lines in radiant distribution networks, diagnosing faults a network is very difficult. It of great significance to identify different types quickly and accurately for the stable operation power grid. This research presents fault identification model based on artificial neural networks. The principal component analysis first extracts features from transitory data network. resulting low-dimensional subsequently used update model. may also type fault. proposed model’s detection...

A three-phase isolated rectifier features bidirectional power conversion and galvanic isolation, is attractive as a high-efficiency energy system. However, when conventional modulation applied to this rectifier, the excessive DC-link current ripple will result in increasing switching losses or size of inductance, which not cost-effective. In order effectively reduce ripple, paper proposes “six segment” PWM (Pulse Width Modulation) strategy. It can significantly compared with existing “eight...