Three phase three level inverter digital control based on over sample and multi-time calculation

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.

Download Full-text

Digital Control of Three Phase PWM Inverter for UPS Application based on Disturbance Observer and Deadbeat Control.

IEEJ Transactions on Industry Applications ◽

10.1541/ieejias.113.617 ◽

1993 ◽

Vol 113 (5) ◽

pp. 617-624 ◽

Cited By ~ 5

Author(s):

Tomoki Yokoyama ◽

Atsuo Kawamura

Keyword(s):

Digital Control ◽

Disturbance Observer ◽

Deadbeat Control ◽

Pwm Inverter ◽

Three Phase

Download Full-text

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

E3S Web of Conferences ◽

10.1051/e3sconf/201911802071 ◽

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.

Download Full-text