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The decreased demand for new vehicles will put pressure on the economy of the Czech Republic, a country deeply integrated into global value chains, as part of global vehicle production. The aim of this research was to define an appropriate industrial policy for the Czech Republic that will ensure that the country maintains its competitive position in the global market. A constrained optimization model was built, based on input–output analysis, to determine the optimal value-added structure and the intersectoral structure of the Czech economy for the country to retain its exporting character. The optimization problem was solved by using a particle swarm optimization algorithm. The results suggest that the optimal industrial policy plan for the country is the structural transformation of production, mainly targeting the development of technologically advanced sectors of manufacturing (such as: chemicals and chemical products; basic pharmaceutical products; computer, electronic, and optical products; electrical equipment; and machinery and equipment). The suggested restructuring process increased the domestic value-added in gross exports as a share of total exports by 6.77%, creating optimal production capabilities for the economy. The Czech Republic appears to have the potential for the implementation of an industrial policy, avoiding the increasingly vulnerable motor-vehicle sector.

Power System Stability is a major domain of renewed interest for electrical power system researchers worldwide. Among the different stability classification domains, large disturbance rotor angle (transient) stability studies are of high concern due to the decommissioning of conventional power plants which leads to a dramatic decrease of inertia and shortcircuit capacity. In this paper, the superiority of a proposed Supplementary Damping Control (SDC) scheme, concerning with transient stability enhancement, is demonstrated against other existing controls, namely, a common form of low-voltage ride through (LVRT) controller with a post-fault ramp, and Voltage Dependent Active Power Injection (VDAPI) control strategy. Based on the analysis done with the modified IEEE 9 bus system with 52% and 75 % share of wind generation, it has been found that proposed SDC has quick damping of oscillations, and also causes a higher reduction of the magnitude of the first rotor angle swing, and has lesser impact on the overall system frequency performance. The controllers’ performance against rotor angle stability threats is tested via EMT modelling and simulation with RSCAD software, which is a real-time digital simulation (RTDS) platform., Accepted author manuscript, Intelligent Electrical Power Grids, Photovoltaic Materials and Devices

The decommissioning of synchronous generators, and their replacement by decoupled renewable power plants, has a significant impact on the transient stability performance of a power system. This paper concerns with an investigation of the degree of transient stability enhancement that can be achieved in power systems with high shares (e.g., around 75%) of wind generation. It is considered that the wind generators can work either under the principle of current control or under the principle of fast local voltage control. In both cases, a power–angle modulation (PAM) controller is superimposed on the current control loops of the grid side converters of the wind generators. The investigation of the degree of enhancement takes into account different approaches of the tuning of PAM. It considers a simple approach in the form of parametric sensitivity, and also a sophisticated approach in the form of a formal optimization problem. Besides, the paper gives insight on what is a suitable objective function of the optimization problem, which entails the best performance of PAM. The whole investigation is conducted based on a synthetic model of the Great Britain (GB) system, Intelligent Electrical Power Grids

Traditionally, electrical power systems have been based on fossil-fuel fired generation plants to satisfy the load demand. However, due to environmental targets for significant CO2 reduction, a gradual decommission of the aforementioned plants is observed whereas renewable energy sources are gaining gradually increasing momentum, which entails radical changes in the dynamic behavior of electrical power systems. Among the existing renewable energy technologies, variable speed wind generators which utilize full–scale power electronics units, are a preferred technological solution to tackle the variability of renewable energy. Increasing renewable power generation caused a reduction of system inertia and short circuit capacity. This reduction challenges the rotor angle stability of remaining synchronous generators when large disturbance occur. This paper presents a study on modifications of the outer control loops of the grid side converter of wind generators type IV to limit the magnitude of the first rotor angle swing while increasing the overall damping performance of a power system. The study includes a comparison between three different wind generation controllers. Namely, a basic Low Voltage Right Through (LVRT) with a post-fault ramp in the active power injection strategy, a voltage dependent active power injection scheme and a Supplementary Damping control (SDC) method are examined and tested through a power hardware-in-the-loop (PHIL) based test bench. It has been found that SDC supports quick damping of oscillations and high reduction of magnitude of the first swing with respect to the other two control schemes., Accepted author manuscript, Photovoltaic Materials and Devices, Intelligent Electrical Power Grids

During the last few years, electric power systems have undergone a widespread shift from conventional fossil-based generation toward renewable energy-based generation. Variable speed wind generators utilizing full-scale power electronics converters are becoming the preferred technology among other types of renewable-based generation, due to the high flexibility to implement different control functions that can support the stabilization of electrical power systems. This paper presents a fundamental study on the enhancement of transient stability in electrical power systems with increasing high share (i.e., above 50%) of power electronic interfaced generation. The wind generator type IV is taken as a representative form of power electronic interfaced generation, and the goal is to investigate how to mitigate the magnitude of the first swing while enhancing the damping of rotor angle oscillations triggered by major electrical disturbances. To perform such mitigation, this paper proposes a power-angle modulation (PAM) controller to adjust the post-fault active power response of the wind generator type IV, after a large disturbance occurs in the system. Based on a small size system, the PAM concept is introduced. The study is performed upon time-domain simulations and analytical formulations of the power transfer equations. Additionally, the IEEE 9 BUS system and the test model of Great Britain's system are used to further investigate the performance of the PAM controller in a multi-machine context, as well as to perform a comparative assessment of the effect of different fault locations, and the necessary wind generators that should be equipped with PAM controllers., Intelligent Electrical Power Grids

During the last years, electric power generation was based mainly on large centralized fossil fuelled power plants. However, nowadays and in the future, efforts are made to increase the share from renewable sources, as a result of increasing environmental concern. Indeed, in some networks areas, wind generators gradually start to replace conventional synchronous generators, while the European Union has set a “20 - 20 - 20” target plan, which aims to achieve a 20% reduction in green house gas emissions compared to 1990 levels, have 20% of the energy on the basis of consumption coming from renewable sources and a 20% increase in energy efficiency by 2020. Due to the increment of wind generator share, power system stability and reliability may be affected. This is attributed to the fact that the characteristics of wind turbines are different from the ones of conventional plants. Therefore different frequency, voltage and transient stability system performances arise which require different measures to be tackled. This report, underlines the importance of rotor angle stability studies in power systems with high share of power electronic interfaced generation units. These studies are related to the ability of the synchronous generators to remain in synchronism when subjected to large disturbances (e.g. faults). A supplementary damping control as a mitigation solution against rotor angle stability threats is studied in power systems dominated by full-scale power electronics wind generation units. This solution, as it is shown in this report, is cost-effective and is adopted for modification of the outer control of fully decoupled wind generators. Concerning related work reported in existing literature, several researchers have used the frequency deviation as input for power system stabilizer added to the grid side converter of a fully decoupled wind generator, whereas other researchers have used the terminal voltage. However, rotor angle remote signals for damping the Syn, MIGRATE H2020, Electrical Engineering