| 主权项 |
1. A method for computing metrics for loudspeaker protection, comprising the following steps:
(1) providing a loudspeaker, a voltage and a current meter, a speaker protection monitor comprising computational and filtering means, and a speaker protection device; (2) measuring speaker input current and voltage; (3) filtering by band-pass filters speaker input voltage and current values measured wherein the band-pass filtered speaker input voltage and current values measured are described by the equations:
im,bpf(t)=ibpf(t)+εi,bpf(t), andvm,bpf(t)=vbpf(t)+εv,bpf(t)wherein im,bpf(t) is the filtered input current, ibpf(t) is the input current measured, εi,bpf(t) describe the current error signals, vmmbpf(t) describes is the filtered input voltage, Vbpf(t) is the input voltage measured, and εv,bpf(t) describe the voltage error signals;
(4) using cross-correlation and autocorrelations equations based on band-passed measurement results to compute loudspeaker protection metrics including a real part of impedance of a voice coil of the loudspeaker, wherein components of the cross-correlation and autocorrelations equations comprise following equations of instantaneous products required for computations of correlations:
ii(t)=im,bpf(t)·im,bpf(t),iv(t)=im,bpf(t)·vm,bpf(t), andvv(t)=vm,bpf(t)·vm,bpf(t); (5) activating speaker protection device if the real part of the loudspeaker impedance exceeds a threshold; and (6) going back to step (2) if input signals of speaker are active. |
