AC regenerative electric drives (AC REDs) are widely used in metallurgical rolling due to their reliability, efficiency, and power sufficient to maintain the process. This paper reviews the latest ...achievements in building the grid connection circuits for the main AC REDs of rolling mills. The paper discusses multipulse connection circuits formed by various transformer types and algorithms for preprogrammed pulse-width modulation with selective harmonic elimination technique (PPWM with SHE) of three-level active front ends (AFE), provides the theoretical and practical measurement results, and gives recommendations for improving existing systems. For 6-, 12-, and 18-pulse grid connection circuits, switching patterns of AFE semiconductor modules with a smooth downward trend within the modulation index range from 0.7 to 1.15 are provided. A simulation was performed under comparable conditions on simulation models in the Matlab/Simulink to objectively evaluate the performance and opportunities of 6-, 12-, and 18-pulse grid connection circuits, including the three-level AFE and transformer specifications. The waveforms and spectra of the grid currents and transformer secondary winding phase currents are shown; total harmonic distortion (THD) factors have been calculated up to the 60th harmonic for various PPWM with SHE patterns. The results of simulation and experimental measurement on operating equipment have been compared. The paper is expected to provide a broad overview of multipulse connection circuits of the rolling mill’s main AC REDs, in particular, identify the latest solutions capable of significantly improving their electromagnetic compatibility with the grid. The results obtained are of high genericity and can be used by researchers and engineers to provide the electromagnetic compatibility of non-linear consumers in similar circuits, as well as design them.
The problem of power stabilization in electric drives has been well studied. There exist numbers of approaches around the problem which consider the input power alone and suffer to achieve higher ...performance in power stabilization. To handle this issue, an efficient Drive State Analysis based Electric Drive Control model (DSA-EDCM) is presented in this article. The model monitors the drive state of electric drive at each duty cycle. According to the drive state and its previous conditions like voltage consumption, voltage leak, rpm and torque required, the method performs drive state analysis. The drive state analysis algorithm computes the power required at different conditions by computing Power Support value (PSV). Based on the PSV value, the method selects specific drive according to the input voltage received. Selected drive has been triggered for the cycle to maintain power stability. The proposed model improves the performance of power stability and maximizes the utilization performance.
A promising way to optimize the technical and economic characteristics of an ac electric drive is to have it designed based on an executive synchronous motor with an increased number of stator ...winding phases. However, due to the specific nature of the
m
-phase (
m
> 3) synchronous motor determined by the energy transfer by a whole spectrum of spatial field harmonics, electromechanical systems should be developed that take this feature into account. A method to study the adjustment characteristics of an
m
-phase synchronous motor is used, which is based on spectral vectors of electromagnetic parameters reduced to spatial field harmonics. A multichannel concept of realization of an
m
-phase synchronous electric drive is proposed, which enables targeted formation of the electromagnetic state of a synchronous motor through all its energy channels as a control object. Various ways of its implementation are considered. The advantages of the multiphase synchronous motor can be realized based on of the forced mutual orientation of the flux linkage vectors and the stator current for higher spatial harmonics, which provides the generation of additional constant components of the electromagnetic torque. This design of electric drives is advisable, in particular, for mobile installations with low-voltage (standalone) power sources.
Brushless dc electric motors have found application in various branches of domestic technology, including in highly important aviation applications, the creation of the electrical complexes of which ...requires minimizing the weight and size indicators of all elements. However, due to the fact that such systems are often constructed on the basis of complex unique transmission mechanisms, their optimization is reduced to the constructive elaboration of the executive electric motor. For electromechanical converters with nonoverlapping concentrated multisection windings used in multipole machines, it is possible to achieve a significant reduction in the total mass by varying the height of the teeth and the length of the machine, taking into account the accepted volume restrictions. This kind of approach to the design of electric machines with a fractional number of slots per pole and phase allows one to create a magnetic system that provides a minimum of the mass of the product while maintaining the required electromechanical parameters by changing the tooth zone. The results obtained will make it possible, even at the stage of creating the sketch appearance of the magnetic system of the executive electric motor, to determine the optimal ratios of the parameters of the magnetic circuit, taking into account the possible minimum mass, which is relevant in the design of structurally complex electromechanical aviation systems.
The current source inverter (CSI) is a power electronics topology that allows for the realization of variable speed drives (VSD). Compared to the most common voltage source inverter (VSI), which can ...be directly connected to a voltage source, the CSI needs a prestage to generate a constant current bus. This article therefore seeks to challenge this "accepted" consideration that a CSI always needs this precircuit and seeks to remove this circuit by proposing an innovative <inline-formula><tex-math notation="LaTeX">i_{dc}</tex-math></inline-formula> current control scheme. The proposed scheme is applied to a single stage motor drive driven by a CSI converter. It is shown how implementing this control scheme removes the need for the front-end stage, thus removing an unnecessary converter and optimizing the efficiency at the same time. The CSI state-space equations are presented and the developed models are verified using simulations. Stability analysis of small-signal model is considered through Nyquist criterion with the robustness in presence of variations of the most important system parameters. Experimental results driving a permanent magnet synchronous machine (PMSM) are shown confirming the validity of the proposed control, potentially paving the way to a larger adoption of the CSI topologies for motor drive applications.
•The model predictive control (MPC) represents a modern alternative to the classical electric drive control strategies.•Utilizing the L1-norm to penalize the speed in a cost function of the MPC ...criterion leads to the faster drive stabilization.•The advantages of the L1-norm stand out especially when the complete continuous control domain is considered.•The time-to-go function in the terminal cost helps to reduce computational demands while long-horizon benefits remain.•Based on the designed terminal cost, fast industry-ready MPC solution to the electric drive control problem is found.
This paper deals with the model predictive control of an electric drive system. Particularly, it focuses on the use of the L1-norm to penalize a speed deviation in a cost function of the predictive control criterion. The benefits and disadvantages of such penalization are discussed considering a model of permanent magnet synchronous motor. The main goal of the paper is to achieve a feasible predictive control algorithm with the L1-norm cost. This proceeds in two stages. First, the long-horizon part of the criterion is approximated by an appropriately designed terminal cost. Second, the short-horizon part is reduced, which facilitates optimization over a continuous control domain. Validity of the approximations and considerations are demonstrated using a set of numerical examples.
This study investigates the effect of 50-kW (about 2C) direct current fast charging on a full-size battery electric vehicle's battery pack in comparison to a pack exclusively charged at 3.3 kW, which ...is the common alternating current Level 2 charging power level. Comparable scaled charging protocols are also independently applied to individual cells at three different temperatures, 20 °C, 30 °C, and 40 °C, to perform a comparative analysis with the packs. Dominant cell-level aging modes were identified through incremental capacity analysis and compared with full packs to gain a clear understanding of additional key factors that affect pack aging.
While the cell-level study showed a minor impact on performance due to direct current fast charging, the packs showed a significantly higher rate of capacity fade under similar charging protocols. This indicates that pack-level aging cannot be directly extrapolated from cell evaluation. Delayed fast charging, completing shortly before discharge, was found to have less of an impact on battery degradation than conventional alternating current Level 2 charging.
•Implications of direct current fast charging on pack and cell.•Minimal impact to performance due to direct current fast charging.•Pack degradation cannot be directly inferred from cell evaluation.•Delayed charging improves battery life across multiple charging regimes.
The dynamics of exoskeleton model placed on a movable flying base of Flyboard Air type is considered. The impact of electric drive spinning rotors on the exoskeleton dynamics is examined. The ...importance of taking this impact into account in developing an operating mechanism is established.
This article presents the results of energy consumption research for an electric light commercial vehicle (eLCV) powered by a centrally located motor (4 × 2 drive system) or motors placed in the ...vehicle’s wheels (4 × 4 drive system). For the considered constructions of electric drive systems, mathematical models of 4 × 2 and 4 × 4 drive systems were developed in the Modelica simulation environment, based on real data. Additionally, the influence of changes in the vehicle loading condition on the operation of the motor mounted in the wheel and the energy consumption of the drive module was investigated. On the basis of the conducted research, a comparative analysis of energy consumption by electric drive systems in 4 × 2 and 4 × 4 configurations was carried out for selected test cycles. The tests carried out with the Worldwide harmonized Light vehicles Test Cycles (WLTC) test cycle showed a roughly 6% lower energy consumption by the 4 × 4 drive system compared to the 4 × 2 configuration.
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