船用多缸柴油机各缸功率均匀性故障检测方法

摘要

At present ,an effective fault detection method for the power uniformity of marine multi-cylinder diesel is still lacking .However ,the most effective cylinder pressure detection method is diffi-cult to use widely due to costly measuring instruments and complicated detecting process .Now ,it is possible to make a less accurate analysis only according to the parameters of burst pressure and ex -haust temperature .The diesel instantaneous rotate speed which contains abundant information can in-directly reflect and easily measure cylinder pressure ,so it may be used as the effective information source for detecting power uniformity fault .It is applied to the simulation of the multi-cylinder power non-uniformity fault in 6-135 type diesel by adjusting the fuel ejection of some cylinders .After the measurement and analysis of the diesel instantaneous speed signal ,the relative value of each cylinder speed rise is taken as effective fault characteristics .Normally , the relative value fluctuates in the range of ± 10% .If the value reduces by more than 10% ,the corresponding cylinder may have a fault of lower power .The method can be used to diagnose the multi-cylinder power non-uniformity fault so correctly as to provide a new approach for the analysis of power uniformity degree of multi-cylinder diesels .%当前，船舶多缸柴油机普遍缺乏有效的各缸功率均匀性故障检测手段，最为有效的缸内压力检测法受限于昂贵的测试仪器和复杂的检测过程而难以广泛应用，目前仅能根据各缸爆压、排温等参数进行准确度不高的分析。柴油机瞬时转速信号能够间接反映缸内压力，它包含丰富的信息量，测量方便，可以作为各缸功率均匀性检测的有效信息源。据此对6-135型柴油机通过调整部分气缸喷油量的方法进行各缸功率不均匀故障的模拟，通过对其瞬时转速信号的测试和分析，从中提取各缸瞬时转速升程相对值作为有效故障特征。正常状态下，各缸瞬时转速升程相对值变化范围在±10％以内，若该参数下降超过10％，可认为对应的气缸存在发出功率偏少问题。该方法能够正确判断各缸功率均匀性故障，可为多缸柴油机工作均匀性分析提供新的检测途径。