附建式变电站振动与二次噪声问题

Vibration and Secondary Noise of Attached Substation

为研究附建式变电站内设备振动诱发的结构振动与二次噪声问题,以武汉市某在建附建式变电站为背景,进行了现场实测并建立了基于舒适度问题的精细化有限元模型,结合实测数据验证了模型准确性,对振动传播规律进行了研究;建立了综合楼有限元模型,对还未建设的敏感房间内振动与二次噪声进行了预测与评价。研究表明:该设备振动及其诱发的结构振动的频率分布均相同,优势频段均在300 Hz以下,卓越频率均为100,200 Hz;各点振动响应仿真值与实测值均具有相同的频谱特性,振动加速度大小也相近,说明本文基于舒适度问题建立的数值计算模型能较好地反应实际结构的动力特性及振动响应;振动在振源同层及沿高度方向传播时均呈整体衰减趋势,但均仅在临近位置处有较大衰减;预测得到的综合楼内振动较不利点舒适度可满足规范要求;最敏感房间内各场点均具有相同的频谱特性,声压幅值均在31.5,50,100 Hz处出现峰值,声压响应最大点等效A声级为36.88 dB,满足规范限值要求。

In order to study the structural vibration and secondary noise caused by equipment vibration in the attached substation,field measurements were carried out and a refined finite element model based on comfort issues was established on the background of an attached substation under construction in Wuhan,the accuracy of the model was verified with the measured data and the law of vibration propagation was studied;a finite element model of the complex building was established to predict and evaluate the vibration and secondary noise in the sensitive room that has not yet been constructed.Research shows that:the frequency distribution of the equipment vibration and its induced structural vibration are the same,the dominant frequency bands are below 300 Hz,and the excellent frequencies are both 100 and 200 Hz;the simulation value of vibration response at each point is relatively close to the measured value,which shows that the numerical calculation model established in this paper can better reflect the actual structure;the vibration shows an overall attenuation trend when the vibration source propagates in the same layer and along the height direction,but it only attenuates greatly at the nearby position;the predicted comfort of the unfavorable point of vibration in the complex building can meet the requirements of the specification;each field point in the most sensitive room has the same spectral characteristics,the sound pressure amplitudes all have peaks at 31.5,50 and 100 Hz,the equivalent A sound level at the maximum point of sound pressure response is 36.88 dB,which meets the requirements of the specification.