Comparison of Various Configuration of Wireless Power Transfer System

This article deals with mutual comparison of different resonant tank configurations of the wireless power transfer (WPT) systems. Tested compensation configurations are classified as series-series, series-parallel, parallel-series and parallel-parallel and all of them are operated with the input and output frequency converters and other supplementary electronics. As parameter we chose the transfer distance and load. The comparison is made according to changes in overall system efficiency and power delivered to the load along varying both the load and operational distance. All theoretical findings are experimentally verified and discussed in the conclusion section

Wireless Power Transmission System for Powering Rotating Parts of Automatic Machineries

This paper deals with the analysis of a suitable compensation topology of a wireless power transmission system for powering the rotating parts of modern automatic machine tools. It summarizes the important properties of the serio-parallel compensation topology suitable for this application and demonstrates a detailed mathematical derivation using the first harmonic approximation. The paper details the industrial implementation of the system in a specific automatic machine tool application and demonstrates the strong technical advantages of the proposed design. Important theoretical conclusions and technical assumptions made when considering the system layout are verified by experimental laboratory measurements and the final deployment of the technology in the professional tool DMU 40 eVo linea

Comparison of active and passive battery balancing

The presented BMS is universal and can be used for most applications using a combination of 15 LiFePo4 type accumulators, which are the most often accumulator type in home battery storage systems. Therefore, the presented system is intended for home battery storage by default. This paper focuses on comparison of two most common balancers for equalizing accumulated charge in cells. The systems are compared with each other in terms of efficiency, complexity and the time required to balance the accumulator

Analysis of Wireless Power Transmission System Behavior for Various Compensation Topologies

This paper presents wireless high-power transfer application in wireless chargers for electro mobility, cordless tools e.g.. It discuses mutual influence of rectifiers and wireless power transfer coupling elements in various compensation topologies. The basic and derived topologies are discussed together with various rectifier topologies. Influencing factors are discussed theoretically and are further practically verified by laboratory testing. Finally, the paper presents optimal wireless power transfer and rectifier topologies combinations for specific application areas of wireless power transfer

Different approach in thermal modeling of permanent magnet synchronous motor

This work deals with different methods of thermal modelling of the stator winding in a slot. The analyzed machine is a permanent magnet synchronous motor (PMSM). The simplified lumped thermal model and model parameters are described. The finite element methods model is set up by different definitions of the winding in a slot. The results of different thermal models of stator winding are shown and discussed

Design, construction and calibration of the current sensor for medium frequency high-power electronic applications

The paper discusses design methodology, constructional alternatives and calibration procedure of current sensor suited for high-power semiconductor systems operated at medium switching frequencies (industrial contact and contactless power chargers). Even there are several types of the sensor on the market, for medium frequency operation they usually exhibit problems with measured signal and its postprocessing. Proposed sensor is designed for a current up to 200 A and 120 kHz and is based on current transformer principle. Design procedure is focused on winding analyses and its impact on operational characteristics. In order to verify proper choice of magnetic core and windings distribution, finite element analysis have been provided to verify magnetization and saturation of sensor core. Consequently, the internal structure of the sensor and its construction is being described, while it is considered that the sensor is equipped with an electronic unit in a common housing. The electronic transducer evaluates the measured data and produces the digital output signals, which are easy to transfer even to a long distance. Prototype of constructed sensor has been undertaken to experimental measurements for given frequency range in order to evaluate quality factors and accuracy. At the end of the paper, the required process of calibration was provided through the evaluation of the algorithm required by digital logic of the sensor.The paper discusses design methodology, constructional alternatives and calibration procedure of current sensor suited for high-power semiconductor systems operated at medium switching frequencies (industrial contact and contactless power chargers). Even there are several types of the sensor on the market, for medium frequency operation they usually exhibit problems with measured signal and its postprocessing. Proposed sensor is designed for a current up to 200 A and 120 kHz and is based on current transformer principle. Design procedure is focused on winding analyses and its impact on operational characteristics. In order to verify proper choice of magnetic core and windings distribution, finite element analysis have been provided to verify magnetization and saturation of sensor core. Consequently, the internal structure of the sensor and its construction is being described, while it is considered that the sensor is equipped with an electronic unit in a common housing. The electronic transducer evaluates the measured data and produces the digital output signals, which are easy to transfer even to a long distance. Prototype of constructed sensor has been undertaken to experimental measurements for given frequency range in order to evaluate quality factors and accuracy. At the end of the paper, the required process of calibration was provided through the evaluation of the algorithm required by digital logic of the sensor

Magnetic wheel optimization for undercarriage of self-acting robot

This paper deals with the dimensional and the material optimization of the robot magnetic wheel. A maximum value of the attracting force and the reduction of the weight are demanded. Three calculation techniques were used. The analytical solution shows conversion of the real wheel gap to a fictional constant gap and allows getting the total attracting force under some simplification. A numerical linear model respects dimension of the wheel exactly. Results are comparable with the precious technique. The last one technique is based on a non-linear model. It extends the linear model by accurate characteristics of the steel

Spatial harmonics in multi-phase induction machine

This paper deals with the analysis of spatial harmonic components in multiphase single or double layer windings. It describes the methodology for magnetic field synthesis in the air gap and verifies the results on a five-phase induction machine using finite element method. The conclusion formulates general rules for spatial harmonics in multiphase induction motors

Analytical Method for Compensation Choke Geometry Optimization to Minimize Losses

The article presents an analytical method for optimizing the geometry of the magnetic core of a three-phase compensation choke. The method describes the process of identification the fringing magnetic fields and the corresponding magnetic reluctances of the magnetic core, the flux density calculation even in the case of the core supersaturation and the total losses estimation. It shows finding the trade-off between the size/weight of the inductor and the magnetic core with respect to the overall losses and demonstrates their minimization. The mathematical model for the flux’s identification is based on a standard iterative calculation using the analogy to electrical circuits but includes a new approach to the calculation of fringing magnetic fields caused by the air gapped magnetic core. The presented method is verified by the finite element method (FEM) using the engineering calculation software ANSYS

Comparison of active and passive battery balancing

The presented BMS is universal and can be used for most applications using a combination of 15 LiFePo4 type accumulators, which are the most often accumulator type in home battery storage systems. Therefore, the presented system is intended for home battery storage by default. This paper focuses on comparison of two most common balancers for equalizing accumulated charge in cells. The systems are compared with each other in terms of efficiency, complexity and the time required to balance the accumulator