Electrical signals dataset from fixed-speed and variable-speed synchronous generators under healthy and faulty conditions - Tominaga, Rafael Noboro; Sousa, Luan Andrade de; Rocha, Rodolfo Varraschim; Monaro, Renato Machado; Avila, Sérgio Luciano; Salles, Maurício Barbosa de Camargo; Carmo, Bruno Souza (Data in brief, 2024)