A Novel Universal Model Considering SAGE for MFD-Based Faulty Property Analysis Under RISC in Synchronous Generators

Abstract

This paper proposes a new rotor interturn short circuit (RISC) fault analysis model for the electromechanical property study in synchronous generators. The specific novelty of this model lies in two aspects: 1) It considers that most generators exist static air-gap eccentricity (SAGE), so it analyzes the RISC fault under normal and SAGE, making the model more versatile, and 2) it takes into account not only the short circuit degree but also the short circuit position, consequently it is more universal. By feeding the number of short circuit turns (denotes the short circuit degree), the angle between the two slots where the short circuit takes place (denotes the short circuit position) and the detailed parameters of the generator into the model, the developing tendency of the key magnetic flux density MFD-based parameters can be conveniently predicted. The advantages of the proposed model primarily lie in the universality and the calculation speed. It can quickly evaluate the generator operating conditions. The phase current and the electromagnetic torque (EMT) are selected in this paper as the representatives of the electrical parameter and the mechanical parameter, respectively. 2D finite element analysis (FEA) and experimental studies validate the proposed model.

Analysis of rotor winding interturn short circuits affected by the initial dynamic eccentricity in large synchronous condensers

“…As reported in the literature, He et al. [19] analysed rotor inter‐turn short circuit (RISC) faults under static air gap eccentricity (SAGE) conditions. They proposed a new RISC fault analysis model for synchronous generators.…”

“…In actual operation, when an RWISC occurs in a condenser, it is often accompanied by an eccentric fault, placing the condenser in a compound fault condition. As reported in the literature, He et al [19] analysed rotor inter-turn short circuit (RISC) faults under static air gap eccentricity (SAGE) conditions. They proposed a new RISC fault analysis model for synchronous generators.…”

Stator current identification in generator among single and composite faults composed by static air‐gap eccentricity and rotor inter‐turn short circuit

“…In ref. [20], the author has proposed the RISC model for studying the electromechanical parameters in synchronous generators. The advantage of the model is that both RISC and SAGE are taken into account.…”

Impact of stator interturn short circuit fault on shaft voltage in a synchronous generator

“…Different kinds of electrical and mechanical faults occur in synchronous generators after long-term operation [13].…”

“…Different kinds of electrical and mechanical faults occur in synchronous generators after long‐term operation [13]. Comparing with the normal condition, the shaft voltage obviously increases due to the asymmetric magnetic field under the fault and presents the clear time–frequency characteristic.…”