**5. Planning**

Planning wind PV hybrid power system (WPVHPS) involves a cost-effective design on priority. The various aspects that are optimally adjusted before commencing are size, fluctuation of load and generation. But, some design considerations such as tilt angle of PV panel and a hub height of wind turbine too have importance. Besides the priority objective, when the reliability of supply is seen, the optimum number of units plays an important role. The years of service life is also important in planning. Graphical construction and probabilistic approaches in combination with an optimization method are used for planning. Planning has become a multiobjective optimization with multi-dimension.

Yang et al. [29] optimally designed wind- solar-battery system for the minimal annualized cost satisfying the limit of loss of power supply probability (LPSP). The five factors such as number PV module, wind turbine and battery units; module inclination, and height of wind turbine have been optimized by genetic algorithm (GA). The result is indicative that the minimum number of wind turbine with some batteries and PV panels with the location-dependent tilt angle is a good solution.

After going through various traditional approaches for their suitability for wind-PV hybrid systems Sinha et al. [30] suggest for using a hybrid of multiple algorithms which can remove the shortcomings of a single method. Abbassi et al. [31] discuss the battery for energy storage which is slow but super-capacitor is fast in giving away the power to the peak load. The energy management is influenced by proper sizing of these storages. The statistical probability density functions are considered for wind speed and irradiation. Discrete Fourier transform (DFT) of the output power to different fast and slow components is done. Monte Carlo simulation (MCS) for different scenarios is very useful for confirming a design for such stochastic variations of generation and load. One contribution of the storage in such system is towards the frequency management. In a similar line, Arabali et al. [32] suggest a new strategy to meet the controllable heating, ventilation, and air conditioning (HVAC) load with a hybrid-RES and ES system. From recorded weather data and load stochastic model of the wind generation, PV generation, and load are developed by Fuzzy C-Means (FCM) clustering dividing data into 10 clusters to show seasonal variations. A multi-objective GA is employed to get the optimal size, cost, and availability DC micro-grid systems with PV and wind [33]. When planned with high-temporal resolution data increased control, improved export, availability of power and decreased variability than for hourly data set. The diesel generator is initially thought as an alternate supply once power fails because it is well transferrable, standard and has a high power-to-weight ratio [2]. When various DERs are integrated into the system, these can affect the voltage profile of the system and demands frequent tap change, but if the voltage is set based on one fixed point, there may be an overvoltage at another. During planning in addition to

**125**

*6.1.1 Centralized control*

*Grid-Connected Distributed Wind-Photovoltaic Energy Management: A Review*

equipment and inverter control are also to be considered [34].

ing, and voltage regulation of a distribution transformer.

overall operational cost, the capacity of capacitor bank or power factor correction

Energy management system (EMS) is an integration of all the algorithms procedures and devices to control and reduce the usage and the cost of energy used to deliver the load with its specifications. In a critical review [35] it has been pointed out that, most of the EMS for RES is concerned with flow and control of power and efficient battery utilization for its durability. But, a full-fledged control approach is

Wu et al. [36] proposed optimal scheduling of the PV system for saving the timeof-use (TOU) cost. Sichilalu et al. [37] focused on a net-zero-energy building by demand side management. The energy management of a grid-connected WPVHPS has been introduced in hardware [38]. In this paper, the hardware, communication and how to meet its requests and functions are emphasized. The system could manage both grid-connected mode and stand-alone mode. EMS for both standalone and grid-connected hybrid RES are reviewed by Olatomiwa et al. [39]. EMS based on linear programming, intelligent techniques and Fuzzy logic controllers is discussed for various combinations. In the study [40] an EMS for controlling end-user building loads, AC, light, ice storage discharge, with adequate solar rooftop PV systems in groups to absorb PEV penetration using practical charging situations are developed without delaying EV charging. The EMS is developed in [41] for a micro-grid with RES that checks net excess generation, battery power and SOC and takes the decision whether to charge/discharge the battery, reduce PV generation, shed load or increase generation of PV by MPPT to control load end voltage. Boukettaya et al. [42] developed a supervisory control in a MG with WPVHPS, a flywheel energy storage system (FESS). Reihani et al. [43] studied the EMS for a MW-range battery energy storage system (BESS) with actual grid data serving for peak load shaving, power smooth-

A distributed algorithm that extracts renewable energy sources on high priority through monitor and prediction of generation and loads online is proposed in [44]. It works to reduce cost and improve system stability. In [45] reports a battery management system (BMS) based on physics-based models of lithium-ion (Li-ion) batteries and vanadium redox-flow (VRF) BESS. In [46] a VRF storage device for frequency regulation and peak-shaving tasks is demonstrated. Multiple BMSs are required in order to reach the desired capacities at grid level demand. A part of the (EMS) in order to achieve specific operational objectives is described in [47]. Gelazanskas et al. [48] review demand-side management (DSM) and DR, including incentives, non-critical load scheduling and peak shaving methods.

Vasiljevska et al. [49] demonstrated an EMS in a medium voltage (MV) network with several MGs by a hierarchical multi-level decentralized arrangement. A power management system (PMS) is proposed for a PV-battery-based hybrid DC/AC MGs for both grid-connected and islanded modes [50]. It balances the power flows, regu-

A grid-connected hybrid system with battery is studied and tested for centralized control under three scenarios by [51]. The control strategy developed could

lates bus voltage automatically under different operating circumstances.

*DOI: http://dx.doi.org/10.5772/intechopen.88923*

**6. Operation**

**6.1 Energy management**

yet to be developed.

overall operational cost, the capacity of capacitor bank or power factor correction equipment and inverter control are also to be considered [34].
