Single-Phase Charging Circuit for Three-Phase Motor Rotor Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric traction chains with permanent magnets in the rotor are not practical for charging via a one-phase power line due to unequal charging of stator inductors, causing the rotor to move during charging.
Innovation Solution
A circuit with a three-phase DC to AC converter and a full-bridge rectifier configuration using additional diodes in series, connected to the DC terminals, allowing for charging via a single-phase alternating current signal and efficient power management to prevent rotor movement during charging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a one-phase power line is used for charging an electric traction chain with permanent magnets in the rotor, then the charging process can be simplified, but the stator inductors are not equally charged causing the rotor to move
Solution Approach 1:
A coupling inductor is introduced as an intermediary component between the single-phase power line and the three-phase electrical machine. This coupling inductor transforms the single-phase input into a three-phase output, enabling equal charging of all stator inductors and preventing rotor movement while maintaining charging simplicity
Solution Approach 2:
The circuit configuration changes from direct single-phase connection to a transformed three-phase connection through the coupling inductor. This parameter change in the electrical connection topology ensures balanced current distribution across all stator inductors, stabilizing the rotor during charging
2Adaptability or versatility
If additional rectifying elements are added to create a full-bridge rectifier for single-phase charging, then charging capability is improved, but component count increases
Solution Approach 1:
The DC to AC converter's rectifying elements serve dual purposes: they function as part of the full-bridge rectifier for single-phase charging and simultaneously operate as part of the three-phase inverter for motor driving. This multi-functionality enables charging adaptability without proportionally increasing component count
Solution Approach 2:
The rectifying elements of the DC to AC converter are merged with additional rectifying elements to form a unified full-bridge rectifier structure. This combination allows the same hardware to handle both single-phase charging and three-phase motor control functions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables efficient charging and driving of a three-phase electrical machine with a low component count, ensuring stable operation and preventing rotor movement during charging, thus enhancing safety and practicality.
Implementation Method 1
a full-bridge rectifier can be created. Half the rectifier is provided by the additional two diodes, the other half is provided by the inverter. This allows charging of a battery by means of an alternating current signal.
Implementation Method 2
A three-phase DC to AC converter comprising a plurality of switches and rectifying elements, two DC terminals for connecting the battery to the circuit and three phase terminals for connecting the circuit to the inductors
Data Source
AI summary
A circuit is provided for charging a battery and for driving an electrical machine. The circuit includes at least three static inductors in Wye configuration having a first charging terminal connected to the center point. The circuit also includes a three-phase inverter having switches and rectifying elements, two DC terminals for connecting the battery to the circuit, and three phase terminals for connecting the circuit to the inductors. The circuit also includes a first rectifying element and a second rectifying element connected in series, with a second charging terminal between the first rectifying element and the second rectifying element. The series of the first rectifying element and the second rectifying element is connected to the inverter parallel to the DC terminals and the first rectifying element and the second rectifying element have the same orientation as the rectifying elements of the inverter as to form a full-bridge rectifier.