Sánchez Moreno, JoséDormido Bencomo, SebastiánMiguel Escrig, OscarRomero Pérez, Julio Ariel2024-05-292024-05-292021-08-20Sánchez Moreno, J., Dormido Bencomo, S., Escrig, O. M., & Romero Pérez, J. A. (2021). Asymmetric delayed relay feedback identification based on the n-shifting approach. International Journal of Control, 97(1), 59–71. https://doi.org/10.1080/00207179.2021.19629680020-7179; eISSN: 1366-5820https://doi.org/10.1080/00207179.2021.1962968https://hdl.handle.net/20.500.14468/22205The paper presents an improvement of the n-shifting technique to identify the frequency response of an industrial process using a fully asymmetric and delaying relay. The n-shifting approach allows the calculation of n + 1 points of G(s) by an asymmetric relay experiment. This set of n points is composed of G(0), G(jωosc), . . . , G(jnωosc), being ωoscthe oscillation frequency, and where G(jωosc) is in most cases located in the third quadrant of the Nyquist map. By delaying the relay output and repeating a similar experiment it can be generated n additional points of G(s) where the first point is G(jω’ osc) with 0 < ω’osc < ωosc. In this way, it is possible to depict the full output spectrum of G(s) from zero to very high frequencies by a short relay experiment. An example of identification and tuning of a PID controller with data from the n-shifting are presented to show the validity of the approach.en12 Matemáticas::1203 Ciencia de los ordenadores ::1203.17 Informáticajournal articleasymmetric relayestimationsystem identificationoscillation