Three-phase

About: Three-phase is a research topic. Over the lifetime, 16801 publications have been published within this topic receiving 159477 citations.

Comparative study of current vector control performance of alternate fault tolerant inverter topologies for three-phase pm brushless ac machine with one phase open circuit fault

Abstract: Reliability and fault tolerance of drive systems has received renewed research interest over last decade with several fault tolerant drive topologies and control schemes having been proposed and investigated. In this paper, the performance of hysteresis current vector control methodologies when applied to three common fault tolerant drive topologies has been investigated and compared theoretically and experimentally. Their advantages and limitations in terms of current value, current and torque ripples, and operating speed range etc. are considered and verified by both simulated and measured results. It is proven that by simply modifying the hysteresis current control methodology, the maximum torque per ampere (MTPA) can still be achieved in post-fault operation, albeit with potentially increased current value, low frequency current and torque ripples, and compromised speed operating range. (6 pages)

Grid simulator for power quality assessment of micro-grids

Abstract: In this study, a grid simulator based on a back-to-back inverter topology with resonant controllers is presented. The simulator is able to generate three-phase voltages for a range of amplitudes and frequencies with different types of perturbations, such as voltage sags, steady-state unbalanced voltages, low-order harmonics and flicker. The aim of this equipment is to test the performance of a given system under such distorted voltages. A prototype of the simulator, consisting of two inverters connected back-to-back to a 380 V three-phase grid and feeding a micro-grid composed of two-inverter interfaced distributed generators and a critical load was built and tested. A set of experimental results for linear purely resistive loads, non-linear loads and current-controlled inverters is presented to prove the capabilities of the simulator. Finally, a case study is presented by testing a micro-grid.

Dynamic Modeling of Dual Three-Phase IPMSM Drives With Different Neutral Configurations

Abstract: Without prior knowledge of the geometric and design data of the employed asymmetrical dual three-phase interior permanent magnet synchronous machine (ADT-IPMSM), this paper proposes effective fundamental and enhanced harmonic models along with parameter identification for the different subspaces and with different neutral point configurations. The cross coupling between the coordinates of the different subspaces is also taken into account. The proposed method is based on simple experimental tests that can be applied to any ADT-IPMSMs. The performed computer simulations coincide to a high extent with experimental validations on a 2.5-kW ADT-IPMSM prototype.

Three phase SCR rectifier bridge with soft start control IC

Abstract: A soft start circuit for controlling a rectifier circuit, the rectifier circuit for converting power from an AC source having one or more phases to DC power having an output voltage (Vo) from a Vo+ node to a Vo- node, the rectifier circuit including: (i) at least first and second rectifier legs coupled from the Vo- node to the Vo+ node, each rectifier leg including a diode and a silicon controlled rectifier (SCR), wherein anodes of the diodes are coupled to the Vo- node, cathodes of the diodes are coupled to anodes of the SCRs at AC input nodes, and cathodes of the SCRs are coupled to the Vo+ node; and (ii) a bus capacitor coupled from the Vo+ node to the Vo- node, the soft start circuit operable to control respective firing angles of the SCRs such that: (i) the output voltage substantially linearly ramps from a low initial value to a relatively high final value, and (ii) charge up currents into the bus capacitor are controlled.

Correlation based method for phase identification in a three phase LV distribution network

Abstract: Low voltage distribution networks feature a high degree of load unbalance and the addition of rooftop photovoltaic is driving further unbalances in the network. Single phase consumers are distributed across the phases but even if the consumer distribution was well balanced when the network was constructed changes will occur over time. Distribution transformer losses are increased by unbalanced loadings. The estimation of transformer losses is a necessary part of the routine upgrading and replacement of transformers and the identification of the phase connections of households allows a precise estimation of the phase loadings and total transformer loss. This paper presents a new technique and preliminary test results for a method of automatically identifying the phase of each customer by correlating voltage information from the utility's transformer system with voltage information from customer smart meters. The techniques are novel as they are purely based upon a time series of electrical voltage measurements taken at the household and at the distribution transformer. Experimental results using a combination of electrical power and current of the real smart meter datasets demonstrate the performance of our techniques.