Combined heat and power system used in e.g. home, has signal processing unit that measures sound signal of microphone such that frequency and phase of acoustic signal are defined based on frequency and phase of alternating current

摘要

The combined heat and power plant has a generator (6) for generating an alternating current. A stirling engine (1) is provided to drive the generator. An active noise reduction system is equipped with signal processing unit (8) which is connected with microphones (7) and an anti-noise source (9) provided within a common housing (13). The signal processing unit measures sound signal of microphone such that the frequency and phase of acoustic signal are defined based on the frequency and phase of the alternating current.