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Electric model based in the duality between the electric and magnetic circuit taking into account the misalignment characteristic of transformer of a Wireless Power Transfer, WPT, is proposed. Being a model based in the constructive characteristic of the transformer the model, it represents better the misalignment effect and the simulation values are more accurate in comparison with the T model that...
Highly dynamic DC-machines, used in low power applications, often contain ironless or so called bell shaped windings. Because there is no massive iron core to support the windings, one of the limiting factors for the torque of the machine is the force on the single wires of the copper weave. Therefore, the knowledge of the force distribution on the single wires could be a helpful design criterion...
Conventional model predictive control (MPC) presents high steady state ripples due to the application of only one voltage vector during one control period. Furthermore, the enumeration-based evaluation of the cost function poses high computational burden. Recently two-vector-based MPC has been proposed to improve the steady-state performance, but it still requires many calculations to obtain the two...
Many islands in China are far from the mainland and electricity is difficult to cover or the cost is high, due to this issue, the wind energy, wave energy and solar energy can be used to meet the demand of island power supply. However, the energy density of these renewable energy sources is low and the stability is poor, which may cause power supply instability. To deal with this issue, a multi-energy...
In this paper, control system and simulation of an arc-linear permanent-magnet synchronous machine with normal armature windings and compensation windings are researched. Considering the special structure of the machine, the mathematical model of the machine is investigated and established. The control scheme and the control system for the machine are also researched to reduce the torque ripple for...
The heating and cooling is very complex process for winding in large power transformer, which involves fluid dynamic, manufacture technology and numerical heat transfer and other related disciplines. Recently, the electromagnetic-Fluid-thermal coupled method and thermal network method are widely used by domestic and foreign researchers, whereas the oil flow distribution can not be taken into account...
To improve the performance of the bearingless induction motor (BIM) under disturbances, a nonsingular fast terminal sliding mode control (NFTSMC) strategy is proposed. The sliding mode surface is designed as a combination of linear sliding mode and nonsingular terminal sliding mode. Besides, considering the power function of the state variables, which make the approaching speed correlate with the...
Linear compressor is becoming more utilized in refrigeration for high efficiency, compared with the traditional rotary motor. Both stroke and frequency controls need to implement for steadiness and efficiency. In this paper, a strategy of resonant frequency tracking control based waveform fitting phase detection is presented to optimize the efficiency of the compressor. Compared with zero crossing...
Linear induction motor (LIM) drive suffers heavily from low efficiency due to its large air-gap length, the end-effects, and the partial load working conditions. Therefore, an optimization method is proposed in this paper to improve the LIM drive operating efficiency from both design and control levels. First, the genetic algorithm (GA) is applied to design optimization of LIM to attain higher efficiency...
Temperature rise is one of the main factors that affect the safe operation of electric vehicle. In order to improve the heat efficiency of the motor, the water-cooled motor of circular circumferential waterway for mini electric vehicle was studied as an object in this research, the structural parameters of the channel are optimized and analyzed from the following aspects: the width of the adjacent...
In this paper, we present the performance of massively parallel processing in finite element electromagnetic field analyses with time periodic explicit error correction. The Domain decomposition technique is used for parallelization, and the Message Passing Interface (MPI) library is used for processing communications. Results show over a 64-fold speed increase compared with the sequential solver,...
In view of the appearance of asymmetrical operation condition in the air-cooled turbo-generator, the negative sequent current is caused in stator windings, which may endanger the stability of the turbo-generator. With the 2-D and 3-D direct coupled transient electromagnetic field, the end region electromagnetic field distribution with the rated condition and single-phase earth fault condition is studied...
In order to improve the efficiency of high voltage power supply for electron beam welder, the characteristics of LCC series parallel resonant converter with capacitive filtering are studied in this paper, and the circuit model of LCC resonance in discontinuous current mode(DCM) is established. The working mode of the converter is analyzed by mathematical time domain analysis method, and the mathematical...
Most of magnetic encoder ICs are on-axis, and they are generally suitable for inner rotor PMSM, sometimes used in external rotor PMSM. However, in some special occasions, these ICs are not used for the difficulty of mounting, for example, there is an external rotor PMSM with a hollow shaft, which is convenient for passing the control wire. It is difficult to mount these encoder ICs, because there...
This paper presents an electro-thermal based junction temperature (Tj) estimation method of insulated gate bipolar transistor (IGBT) power module. Firstly, the internal structure of IGBT and its transient characteristics are researched, through which the factors affecting the power loss as well as its basic influence rule are analyze and the multivariable loss calculation model is obtained. And then...
A new approach for the computation of electric fields is described, based on the response surface methodology(RSM) and geometric feature charge simulation method (GFCSM). And the novel combination of RSM and GFCSM is applied to calculate the electric field of the high voltage SF6 arc quenching chamber in this paper. The electric field distribution with higher calculation precision has been achieved...
Spray cooling is a new type of high heat flux heat transfer cooling technology. In the process, cooling medium is dispersed certain microscale droplets through the nozzles and injected to the stator core and winding. The spray characteristics will affect directly the heat transfer coefficient. So in the paper a test rig using a nozzle was constructed to explore the atomization characteristics of spray...
In this paper, an improved control strategy (ICS) based on the duty ratio modulation, by properly matching the positive voltage vectors with the new zero voltage vectors (ZVVs), is proposed in direct torque control (DTC) of brushless DC motor (BLDCM). The traditional voltage switching table for the six switches of the converter is modified according to this strategy to minimize the torque ripple....
This paper presents a rotor position estimated method of a five-phase IPM motor based on high-frequency sinusoidal voltage injection to improve the sensorless control system performance at low speed for electric vehicles. The high-frequency sinusoidal voltage is injected into the estimated rotor reference frame. The estimated rotor position and speed are obtained by detecting and processing high-frequency...
This, paper presents a model predictive control (MPC) scheme and its model reduction approach for the brushless doubly fed twin stator induction machine (BDFTSIM). Firstly, the state-space equations of BDFTSIM, in terms of (power winding) PW flux, (rotor winding) RW flux, and (control winding) CW flux, is derived for developing the complete power model which is explicitly used to predict the future...
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