A new switching time calculation algorithm for SPWM three-phase voltaje source inverter

2017 ◽  
Author(s):  
Andres Cervantes-Hernandez ◽  
Gustavo Velazquez-Gaytan ◽  
Jose Luis Monroy-Morales
Keyword(s):  
Switching Time ◽  
Calculation Algorithm ◽  
Three Phase ◽  
Time Calculation

scholarly journals Ultraprecision Real-Time Displacements Calculation Algorithm for the Grating Interferometer System

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2409 ◽  
Author(s):  
Weinan Ye ◽  
Ming Zhang ◽  
Yu Zhu ◽  
Leijie Wang ◽  
Jinchun Hu ◽  
...  
Keyword(s):  
Real Time ◽  
Affine Transformation ◽  
Degrees Of Freedom ◽  
Diffraction Spot ◽  
Calculation Algorithm ◽  
Six Degrees Of Freedom ◽  
Time Calculation ◽  
Interference Signals ◽  
Grating Interferometer ◽  
Optical Paths

Grating interferometry is an environmentally stable displacement measurement technique that has significant potential for identifying the position of the wafer stage. A fast and precise algorithm is required for real-time calculation of six degrees-of-freedom (DOF) displacement using phase shifts of interference signals. Based on affine transformation, we analyze diffraction spot displacement and changes in the internal and external effective optical paths of the grating interferometer caused by the displacement of the wafer stage (DOWS); then, we establish a phase shift-DOWS model. To solve the DOWS in real time, we present a polynomial approximation algorithm that uses the frequency domain characteristics of nonlinearities to achieve model reduction. The presented algorithm is verified by experiment and ZEMAX simulation.

scholarly journals On Speed Control of a Permanent Magnet Synchronous Motor with Current Predictive Compensation

Energies ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 65 ◽  
Author(s):  
Meiling Tang ◽  
Shengxian Zhuang
Keyword(s):  
Permanent Magnet ◽  
Current Model ◽  
Permanent Magnet Synchronous Motor ◽  
Synchronous Motor ◽  
Sampling Step ◽  
Phase Current ◽  
Speed Tracking ◽  
Three Phase ◽  
Time Calculation ◽  
Predictive Controller

In this study, a current model predictive controller (MPC) is designed for a permanent magnet synchronous motor (PMSM) where the speed of the motor can be regulated precisely. First, the mathematical model, the specifications, and the drive topology of the PMSM are introduced, followed by an elaboration of the design of the MPC. The MPC is then used to predict the current in a discrete-time calculation. The phase current at the next sampling step can be estimated to compensate the current errors, thereby modifying the three-phase currents of the motor. Next, Simulink modeling of the MPC algorithm is given, with three-phase current waveforms compared when the motor is operated under the designed MPC and a traditional vector control for PMSM. Finally, the speed responses are measured when the motor is controlled by traditional control methods and the MPC approach under varied speed references and loads. In comparison with traditional controllers, both the simulation and the experimental results suggest that the MPC for the PMSM can improve the speed-tracking performance of the motor and that this motor has a fast speed response and small steady-state errors under the rated load.

scholarly journals Research on the Device Design for Calculation Distribution Line Loss Based on Dynamic Three-phase Unbalance Degree

2019 ◽  
Vol 118 ◽  
pp. 02071
Author(s):  
Meifang Wei ◽  
Jing Yang ◽  
Xuhua Zeng ◽  
Haiyan Wu ◽  
Di Huang
Keyword(s):  
Real Time ◽  
Distribution Network ◽  
Wireless Transmission ◽  
Loss Calculation ◽  
Sequence Identification ◽  
Phase Sequence ◽  
Three Phase ◽  
Time Calculation ◽  
Distribution Line ◽  
Line Loss

For the power distribution network line loss calculation, there are some problems, such as backward method, long calculation period, large workload and poor real-time performance. To this end, this paper proposes a real-time calculation method for distribution line loss based on dynamic three-phase unbalance, and a hardware device system with unbalanced phase sequence identification function, three-phase unbalance detection function and line loss real-time calculation function has been developed. The system uses a master-slave design based on the principle of wireless transmission. The slave collects standard three-phase current signals and transmits them to the host through wireless transmission. The host is installed on the low voltage side of the transformer in the transformer region, and the current signal of the transformer region is collected in real time. Unbalanced phase sequence identification, unbalance calculation, and line loss calculation based on dynamic unbalance are performed by comparing the current signals collected by the master and the slave. The above algorithm implementation process can be displayed online in real time. In addition to the core data processing and waveform display functions, the device also includes a battery power supply and management system, a signal storage and transmission system, and temperature measurement, and overcurrent and overvoltage protection. The test results of the device show that the device has the characteristics of convenient carrying, fast detection of three-phase unbalance, and accurate calculation of line loss. The device can monitor the running status of the distribution network transformer region in real time.

Rationality optimization of tool path spacing based on dwell time calculation algorithm

2015 ◽  
Vol 84 (9-12) ◽  
pp. 2055-2065 ◽  
Author(s):  
Ri Pan ◽  
Yajun Zhang ◽  
Jianbiao Ding ◽  
Cong Cao ◽  
Zhenzhong Wang ◽  
...  
Keyword(s):  
Dwell Time ◽  
Tool Path ◽  
Calculation Algorithm ◽  
Time Calculation

Analysis of Thyristor Switched Three-Phase Capacitor

2013 ◽  
Vol 722 ◽  
pp. 311-316 ◽  
Author(s):  
Tian Xiang Yan ◽  
Xiao Lan Xie ◽  
Xin Yu Chen ◽  
Peng Niu
Keyword(s):  
Reactive Power ◽  
Power Transmission ◽  
Switching Time ◽  
Transition Process ◽  
Fundamental Principle ◽  
Safe Operation ◽  
Voltage Quality ◽  
Three Phase ◽  
Selection Of

it can limit the reactive power transmission to improve the voltage quality of power grid by installing parallel capacitors for reactive power compensation. But due to presence of transient transition process during power capacitors switching, it will seriously affect the service life of power capacitors and the safe operation of power system if the switching process of capacitors is not properly controlled. Firstly, this article described the fundamental principle and switching conditions of Thyristor Switched Capacitor (TSC). Secondly, the selection of switching time was analyzed for Thyristor Switched Three-phase Capacitor (TSTC). Finally, the simulation for TSTC was carried out by using MATLAB to verify the feasibility of analysis.

Modeling and Identification of Feed Drive Kinematics and Cycle Time Calculation

Manufacturing ◽  
2003 ◽  
Author(s):  
Wencai Wang ◽  
Derek M. Yip-Hoi
Keyword(s):  
Machine Tool ◽  
Cycle Time ◽  
Manufacturing Systems ◽  
Kinematic Model ◽  
Cnc Machine ◽  
Machining Processes ◽  
Calculation Algorithm ◽  
Motion Data ◽  
Feed Drive ◽  
Time Calculation

Cycle time calculation plays a major role in the design of manufacturing systems. Accurate estimates are needed to correctly determine the capacity of a line in terms of the number of machines that must be purchased. Over estimation results in excess capacity and under estimation leads to unsatisfied demand. Due to the high automation and cutting speeds of modern machining processes, cycle time calculation must consider both the timing of various machining actions and the kinematics of feed motions. This paper presents a cycle time calculation algorithm that gives accurate cycle time results by considering the effects of jerk and acceleration of the machine tool drives. The kinematic model for axis motion is based on trapezoidal acceleration profiles along the toolpaths. Based on this model, an algorithm for identifying the kinematic parameters has been developed. This algorithm has the advantage of utilizing a minimal set of axis motion data thus reducing the amount of data that must be collected from experiments by the machine tool vendor or the machine tool’s enduser. The proposed cycle time calculation algorithm has been verified in machining a V6 cylinder head on a four axis CNC machine.

Sign in / Sign up

Export Citation Format

Share Document