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Nowadays the series wound DC traction motor driven locomotives are still widely used. These vehicles inject harmonics into the AC line and distort the line voltage. In our work we examined and compared current control methods that can be achieved by "network-friendly" locomotives connected to the distorted line.The modern locomotives strive to consume sinusoidal current from the AC network, in phase with the network voltage fundamental. We compared current control methods with this "common" strategy. One of them can reduce the consumed root mean square or fundamental current of a distorted line connected modern locomotive in motor mode. Other one can increase the generated RMS and fundamental current in generator mode. With these strategies the harmonic currents can be used for active power. Moreover it turned out that the harmonic content of the network can be reduced by the "new" strategies. We built simulation models and double domain simulation was used for this study.

Modern battery management systems (BMS) for advanced battery energy storages are expected to provide sufficient and reliable State-of-Charge (SoC) and State-of-Health (SoH) IntroductionE-mobility and large-scale stationary energy storages specify even more specific and safety-critical requirements on advanced battery systems, hereby boosting the development need of special purpose electrical battery cell models. In opposite to this, applied research focuses more on the scalability and modularity.In technical point of view, developing electrical battery cell models has two main driving forces. One is the offline (continuous-time with floating-point number representation) circuit simulation of battery systems providing I-V characteristics for electrical system design purpose [1]. In applications, where the battery pack is connected to nonlinear systems (especially high power motor drives, or grid-connected energy storages), it is crucial to verify the designed battery system behavior [2].The other is the online simulation, where the goal is to create a real-time electrical battery cell model, which can be run in real-time simulations and in online, i.e. model-based SoC and SoH estimation algorithms, as well [3,4]. Such online model is essential in advanced battery energy storages. Expected modularity allows extra functions to be attached easily, and the required scalability enables level-to-pack extensions within certain error tolerances and additional dependencies of parameters [5,6]. All these complex requirements lead the developers to switch rather to FPGA from MCU in the BMS for running high performance, online SoC and SoH estimation algorithms. Next to this, if the battery cell model is available in synthesizable form, then one more great advantage is that it can be used also in modern FPGA-based Hardware-In-the-Loop (HIL) simulators. HIL is a test approach, where, in this case, the BMS is tested involving the original BMS electronics and the real-time simulator of the battery on the expected cell-or pack level solving the state equations numerically step by step [7]. By using battery HIL simulator, also the extreme failure cases are reproducible, which is not possible in the real system [8].In this paper, an FPGA-synthesizable electrical battery cell model is introduced using fixed-point number representation, which is designed and verified in MATLAB/Simulink. This online Simulink model can be used in FPGA or in processorbased BMS and also in real-time HIL simulators.

Several non-linear loads are connected to the low voltage public grid, for example: compact fluorescent lamps (CFL) or electronic devices contain switched mode power supplies (SMPS) and diode rectifiers. These distort the grid with current harmonics therefore the grid voltage waveform become distorted. We worked out a new current control strategy for grid-connected inverters of domestic power plants. The root mean square (RMS) value and the fundamental of the generated AC current can be increased and the harmonic content of the network can be reduced with the new method, that we call reversed strategy. We compared it with the commonly used sinusoidal current control method. An analytical comprehension of the two strategies is discussed in this paper. By comparing their consumed RMS and fundamental currents we defined coefficients (k RMS_rev_sin and k fund_rev_sin ), which depend only on the total harmonic distortion of the network voltage (THD U )