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In order to improve the interior sound quality of Electric Vehicles (EV), solve the problem of low sense of power and comfort of the interior sound as well as the large electromagnetic excitation order noise of motor and the sharp interior sound, this article designs a dynamic active sound control system for EV under accelerated driving conditions. Firstly, by comparing and analyzing the sound spectrum characteristics of fuel vehicle (FV) and EV during acceleration, a short-time Fourier transform (STFT) is adopted to extract and synthesize the engine sound. Secondly, the influence of the engine order composition and the energy distribution in the frequency domain on the sound quality of the vehicle is analyzed, and an active control system for sound quality is proposed. And the software and hardware development of the active control sound system is completed. Finally, through real-vehicle testing and verification, the sense of comfort and power of the EV interior sound has been greatly improved during acceleration, and the total value of interior sound can meet the requirement. The sound pressure level and loudness of interior sound have been increased, and the sharpness of the sound inside the vehicle has been improved, with a maximum reduction of 1.0acum. [ABSTRACT FROM AUTHOR]

In order to improve the comfort and dynamic sense of the interior sound of PEVs when driving at a constant speed, this paper carried out research on the evaluation method of the interior sound quality of EVs and the development of an active sound generation system (ASGS). The investigation and research on the sound development trend of EV interiors were carried out. Combined with subjective evaluation methods and test results, a constant-speed vehicle interior sound design method was proposed, which focused on three dimensions: engine order composition, spectral energy distribution, and sound amplitude enhancement in the typical vehicle speed range. The internal sound spectrum of FVs was analyzed, and the engine order sound simulation analysis was completed. It is verified that the short-time Fourier transform and synthesis technology based on Kaiser window function can meet the requirements of engine order sound fitting accuracy. To formulate the sound design plan, control objectives and control methods of an A-class pure electric SUV with both comfort and dynamic sense during accelerated driving, the correlation between the engine order sound amplitude and dynamic sense in the vehicle was analyzed, and the setting of active sound parameters of EVs was clarified. The control hardware and software of ASGS in the vehicle was developed, the construction of ASGS based on the vehicle sound system completed, and test verification was conducted. The objective test of the real vehicle shows that ASGS ensures a low-amplitude interior noise level. When the vehicle speed is 28.6 km/h, the sharpness is reduced by 0.52 acum, and the subjective evaluation test of the real vehicle further verifies that ASGS can improve the comfort and dynamic sound quality of EVs driving at a constant speed. [ABSTRACT FROM AUTHOR]

The feedforward hybrid active noise control (HANC) system combines the strengths of the narrowband ANC (NANC) system and the broadband ANC (BANC) system. Taking this advantage into account, this paper applies it to attenuate the vehicle interior noise mixed with narrowband and broadband components. However, in the HANC system, the NANC subsystem and BANC subsystem are fed a common error signal which depends on the combined secondary signals from the both subsystems. This causes the problem of mutual coupling and hence affects the noise reduction performance. To tackle the problem, we propose a modified HANC (MHANC) system in this paper. In the MHANC system, the error signal of each ANC subsystem is independently synthesized on the basis of the estimated primary and secondary signals. Note that the NANC system for engine order noise control suffers performance deterioration when the fluctuating real-time engine speed signal is used for constructing internal reference signals. For performance improvement, an enhanced NANC (ENANC) system is developed by smoothing the fluctuating engine speed signal. Meanwhile,the ENANC system is incorporated in the MHANC system to form an enhanced MHANC (EMHANC) system. Simulations were performed on the vehicle interior noise recorded under actual driving conditions. The corresponding results demonstrate the superiority of the proposed MHANC and EMHANC systems. [ABSTRACT FROM AUTHOR]