WIND energy is the most accessible source and is one of the fastest growing renewable energy systems. If this energy is exploited properly and well-suited to the turbine system, it would have the ability to compete economically and even be superior to other sources. For this purpose, in the high WIND speed areas different methods are applied in the bases of harvesting as much WIND energy as possible with respect to harness rotor speed at the rated value. In this paper, an extensive literature review on control and manufacturing strategies in power production and system performance of WIND energy conversion system (WECS) has been highlighted. Classic control, adaptive non-linear control, robust control and intelligent control are among the control methods presented in this study. In comparing the controllers, although adaptive and robust controllers, with less sensitivity to changes in environmental conditions, outperformed the classic controller, and the intelligent controller presented better control flexibility and power quality through estimating the system variables and appropriate adaptation to changes at the operating point.

In this paper, an interval Type-2 fuzzy logic based pitch ANGLE controller is proposed for fixed speed WIND energy system (WES) to maintain the aerodynamic power at its rated value. The pitch ANGLE reference is generated by the proposed controller which can compensate the non-linear characteristics of the pitch ANGLE to the WIND speed. The presence of third dimension in the Type-2 fuzzy logic controller (FLC) membership function offers an additional degree-of-freedom in the design of the Type-2 FLC controller to improve the system performance. The applicability of the proposed controller is evaluated by considering a nonlinear simulation model of the WES which is developed and implemented using OPAL-RT real time digital simulator. The results show that the proposed controller offers better performance than the conventional PI and fuzzy logic controllers.

WIND turbine is a complex nonlinear system that the exact model of this system is not available, so it can be represented as an uncertain system. Thus, the control of this system is an important topic. Most of methods that design controllers for WIND turbines consider these systems in suitable weather condition. While many turbines work in cold weather condition, in this paper, WIND turbine is considered in cold weather, and in ice on turbine blades are considered as model uncertainties. A robust controller is designed for the WIND turbine, in order to control the pitch ANGLE. Performance of the proposed controller is evaluated in a comparison study.

Conspicuously, pitch ANGLE control strategy has been applied to mitigate the influence of mechanical load and also output power control at above-rated WIND speeds. In this paper, a WIND turbine is modeled based on simplified two-mass model and an adaptive sliding mode controller (ASMC) is designed based on individual pitch control (IPC) strategy. To do this, the single-blade approach is used and the WIND turbine was divided into aerodynamics and mechanical subsystems and governing equations of each subsystem were derived. By designing and applying the ASMC to two-mass model, system behavior is observed and simulated in terms of step and turbulent WIND speed inputs. In addition, to verify the validity of the ASMC, the proposed controller is implemented in the FAST environment and the WIND speed profiles are generated using TurbSim. In order to analyze the environmental effects on the dynamic behavior of the system, the controller performance is explored in presence of parametric uncertainties. It should be noted that rotor speed tracking error is evaluated and demonstrated through different criteria.

Although fossil fuel resources are declining, their use also pollutes the environment. Also, due to the increase in the average WIND speed in the world, the use of WIND turbines, which are classified in structures with new and renewable energy, will be very cost-effective. WIND turbine towers can be made of concrete, steel, conical, lattice, wood, or multi material. Given that the investment cost to build a WIND farm and connect it to the transmission network is 75 to 85 percent, and the cost of building the structure is 15 to 25 percent of the total cost. Steel lattice towers can reduce the cost of building a WIND turbine structure by 30 percent and therefore, a complete and correct model for analyzing these types of structures will be very important and economically noteworthy. WIND turbine lattice towers are usually made and executed with bolt connections. In this case, the number of bolts is very high, which increases the need for cyclical and reciprocal loads. Joint slip in these structures refers to the relative displacement of bolt connection under the influence of force. Therefore, creating a joint slip will be inevitable due to the ease and speed of execution in which the bolt hole is made of a larger bolt diameter. Joint slip increase the displacement of lattice towers So much so that the maximum displacement of the tower is twice as high as that of static methods. And not considering it will destroy the tower and assuming the reliability factor will make it uneconomical. In this type of structure, the tower is often made of ANGLE and single ANGLEs are used in cross members and bracing and double ANGLEs are mostly used in the bases of lattice towers. With this explanation, in this study, the force curve of the displacement of the of three samples with single ANGLE section in the laboratory and four samples with double ANGLE section in Abaqus software was modeled and were affected by reciprocating loads and then the results of numerical modeling were validated with laboratory samples. In the models modeled in the software, after sensitivity analysis, the type and size of the mesh is precisely minimized the resulting error. In this investigation available data in joint slip develops bolt connections which include ANGLEs with equal leg. It offers force-displacement curve of different connections for double ANGLEs and their connections damping ratio are calculated likewise and the effectiveness of each variable on the slip of the node is expressed in double ANGLEs. The results show that joint slip occurs during service loads and this effect depends on the number of bolt, the diameter of the bolt, the bolt cross-sectional area, the thickness of the ANGLE and the effective cross-sectional area among these, screw diameter is the most important variable for predicting joint behavior. Also, the viscosity damping ratio for single and double ANGLE connections is almost equal and can be assumed to be 42. 5. This ratio increases with increasing number and decreasing bolt diameter. This investigation is beneficial for designing WIND turbine lattice towers and in it, provides structure behavior to the designer more accurately.

The purpose of this paper is optimal location of distributed generation in electric distribution networks. Load uncertainty and desired voltage range has been modeled using fuzzy data theory. The objective function includes loss reduction, improvement of profile index and voltage stability index with their relevant constraints, voltage constraints and transmittable power from the line. Load variation has been shown for three different time durations (peak, off peak and average).PSO technique has been used to optimize the objective function while Max-Min method has been applied to select the answer. Results produced from the proposed model have been provided in 5 different scenarios on a 33 bus system of IEEE.