In order to evaluate the ride quality of the soil compactor cab supplemented by the auxiliary hydraulic mounts (AHM), a nonlinear dynamic model of the soil compactor interacting with the off-road deformable terrain is...In order to evaluate the ride quality of the soil compactor cab supplemented by the auxiliary hydraulic mounts (AHM), a nonlinear dynamic model of the soil compactor interacting with the off-road deformable terrain is established based on Matlab/Simulink sofware. The power spectral density (PSD) and the weighted root mean square (RMS) of acceleration responses of the vertical driver s seat, the cab s pitch and roll angle are chosen as objective functions in low-frequency range. Experimental investigation is also used to verify the accuracy of the model. The influence of the damping coefficients of the AHM on the cab s ride quality is analyzed, and damping coefficients are then optimized via a genetic algorithm program. The research results show that the cab s rubber mounts added by the AHM clearly improve the ride quality under various operating conditions. Particularly, with the optimal damping coefficients of the front-end mounts c a 1,2 = 1 500 N · s/m and of the rear-end mounts c a 3,4 =2 335 N · s/m, the weighted RMS values of the driver s seat, the cab s pitch and roll angle are reduced by 22.2%, 18.8%, 58.7%, respectively. Under the condition of the vehicle travelling, with the optimal damping coefficients of c a 1,2 = 1 500 N · s/m and c a 3,4 =1 882 N · s/m, the maximum PSD values of the driver s seat, the cab s pitch and roll angle are clearly decreased by 36.7%, 54.7% and 50.6% under the condition of the vehicle working.展开更多
A new automatic rotary compactor and its abilities in compacting stone mastic asphalt （SMA） are presented. Following an overview of the rotary compactor and the compaction procedure, it is demonstrated that the rota...A new automatic rotary compactor and its abilities in compacting stone mastic asphalt （SMA） are presented. Following an overview of the rotary compactor and the compaction procedure, it is demonstrated that the rotary compactor is able to produce uniform slabs with the desired thickness of 65 mm all over around. Furthermore, 132 cored samples from the rotary compactor had been compacted uniformly with approximately 4% optimum air void content. In addition, performance tests results indicate that the rotary compactor produces asphalt mixturures with the requirements of resilient modulus, Marshall stability and flow. A weight factor was introduced for each fraction of aggregates in the degradation analysis to compensate the crushing effect of aggregates during mixing and compacting.展开更多
针对目前生物质炭化设备生产率较低、能源消耗大、原料适应性较差等问题,提出生物质连续炭化生产工艺路线,采用内加热热解原理,研发内加热连续式生物质炭化设备。以生物质颗粒燃料等为原料开展炭化试验,试验结果表明;设备生产率为108 kg...针对目前生物质炭化设备生产率较低、能源消耗大、原料适应性较差等问题,提出生物质连续炭化生产工艺路线,采用内加热热解原理,研发内加热连续式生物质炭化设备。以生物质颗粒燃料等为原料开展炭化试验,试验结果表明;设备生产率为108 kg/h,生物炭得率为31%,吨炭电耗为15 k W·h,各项性能指标均达到设计要求,可实现生物炭的连续生产。展开更多
提出一种具有功率因数校正、补偿负载不平衡和滤除电网谐波电流的静止无功补偿器(static var compensator,SVC)和有源电力滤波器(active power filter,APF)联合运行系统电路结构。其中,SVC由晶闸管控制电抗器(thyristor controlled reac...提出一种具有功率因数校正、补偿负载不平衡和滤除电网谐波电流的静止无功补偿器(static var compensator,SVC)和有源电力滤波器(active power filter,APF)联合运行系统电路结构。其中,SVC由晶闸管控制电抗器(thyristor controlled reactor,TCR)及固定电容器(fastness capacitor,FC)组成,主要用来快速补偿无功,并通过对其三相不对称控制来消除电网三相不对称和负序电流;APF部分主要用来消除电网及SVC引起的谐波电流,同时抑制固定电容器与电网等效阻抗间可能的串并联谐振。在分析SVC和APF联合运行系统基本工作原理的基础上,对联合运行时的控制方法进行研究。仿真和实验结果证明了该联合运行系统的可行性。展开更多
针对单相牵引负荷波动性大,随机性强,造成大量谐波、无功及负序分量的特点,提出一种应用于电气化铁路的单相无功动态补偿与谐波治理混合系统(hybrid var and harmonic dynamic compensator,HVHC)。系统由混合型有源电力滤波器(hybrid ac...针对单相牵引负荷波动性大,随机性强,造成大量谐波、无功及负序分量的特点,提出一种应用于电气化铁路的单相无功动态补偿与谐波治理混合系统(hybrid var and harmonic dynamic compensator,HVHC)。系统由混合型有源电力滤波器(hybrid active power filter,HAPF)及静止无功补偿器(static var compensator,SVC)组成,其中SVC包括晶闸管投切电容器(thyristor switched capacitor,TSC)和晶闸管控制电抗器(thyristor controlled reactor,TCR),用来动态连续补偿无功功率,HAPF用来动态抑制电网及无功补偿装置产生的谐波,电力机车产生的负序分量可通过在平衡变压器接线方式下控制2个牵引供电臂的负载来消除。提出HAPF和SVC复合控制策略及分频控制方法,可有效地消除两者之间的耦合,提高单相系统谐波及无功电流的跟踪精度,克服电网电压畸变对系统的影响。仿真及实验结果证明该系统响应速度快,抗干扰能力强,治理效果满足要求。展开更多
基金The Science and Technology Support Program of Jiangsu Province(No.BE2014133)the Prospective Joint Research Program of Jiangsu Province(No.BY2014127-01)
文摘In order to evaluate the ride quality of the soil compactor cab supplemented by the auxiliary hydraulic mounts (AHM), a nonlinear dynamic model of the soil compactor interacting with the off-road deformable terrain is established based on Matlab/Simulink sofware. The power spectral density (PSD) and the weighted root mean square (RMS) of acceleration responses of the vertical driver s seat, the cab s pitch and roll angle are chosen as objective functions in low-frequency range. Experimental investigation is also used to verify the accuracy of the model. The influence of the damping coefficients of the AHM on the cab s ride quality is analyzed, and damping coefficients are then optimized via a genetic algorithm program. The research results show that the cab s rubber mounts added by the AHM clearly improve the ride quality under various operating conditions. Particularly, with the optimal damping coefficients of the front-end mounts c a 1,2 = 1 500 N · s/m and of the rear-end mounts c a 3,4 =2 335 N · s/m, the weighted RMS values of the driver s seat, the cab s pitch and roll angle are reduced by 22.2%, 18.8%, 58.7%, respectively. Under the condition of the vehicle travelling, with the optimal damping coefficients of c a 1,2 = 1 500 N · s/m and c a 3,4 =1 882 N · s/m, the maximum PSD values of the driver s seat, the cab s pitch and roll angle are clearly decreased by 36.7%, 54.7% and 50.6% under the condition of the vehicle working.
基金the Ministry of Higher Education for funding this research
文摘A new automatic rotary compactor and its abilities in compacting stone mastic asphalt （SMA） are presented. Following an overview of the rotary compactor and the compaction procedure, it is demonstrated that the rotary compactor is able to produce uniform slabs with the desired thickness of 65 mm all over around. Furthermore, 132 cored samples from the rotary compactor had been compacted uniformly with approximately 4% optimum air void content. In addition, performance tests results indicate that the rotary compactor produces asphalt mixturures with the requirements of resilient modulus, Marshall stability and flow. A weight factor was introduced for each fraction of aggregates in the degradation analysis to compensate the crushing effect of aggregates during mixing and compacting.
文摘针对目前生物质炭化设备生产率较低、能源消耗大、原料适应性较差等问题,提出生物质连续炭化生产工艺路线,采用内加热热解原理,研发内加热连续式生物质炭化设备。以生物质颗粒燃料等为原料开展炭化试验,试验结果表明;设备生产率为108 kg/h,生物炭得率为31%,吨炭电耗为15 k W·h,各项性能指标均达到设计要求,可实现生物炭的连续生产。
文摘提出一种具有功率因数校正、补偿负载不平衡和滤除电网谐波电流的静止无功补偿器(static var compensator,SVC)和有源电力滤波器(active power filter,APF)联合运行系统电路结构。其中,SVC由晶闸管控制电抗器(thyristor controlled reactor,TCR)及固定电容器(fastness capacitor,FC)组成,主要用来快速补偿无功,并通过对其三相不对称控制来消除电网三相不对称和负序电流;APF部分主要用来消除电网及SVC引起的谐波电流,同时抑制固定电容器与电网等效阻抗间可能的串并联谐振。在分析SVC和APF联合运行系统基本工作原理的基础上,对联合运行时的控制方法进行研究。仿真和实验结果证明了该联合运行系统的可行性。
文摘针对单相牵引负荷波动性大,随机性强,造成大量谐波、无功及负序分量的特点,提出一种应用于电气化铁路的单相无功动态补偿与谐波治理混合系统(hybrid var and harmonic dynamic compensator,HVHC)。系统由混合型有源电力滤波器(hybrid active power filter,HAPF)及静止无功补偿器(static var compensator,SVC)组成,其中SVC包括晶闸管投切电容器(thyristor switched capacitor,TSC)和晶闸管控制电抗器(thyristor controlled reactor,TCR),用来动态连续补偿无功功率,HAPF用来动态抑制电网及无功补偿装置产生的谐波,电力机车产生的负序分量可通过在平衡变压器接线方式下控制2个牵引供电臂的负载来消除。提出HAPF和SVC复合控制策略及分频控制方法,可有效地消除两者之间的耦合,提高单相系统谐波及无功电流的跟踪精度,克服电网电压畸变对系统的影响。仿真及实验结果证明该系统响应速度快,抗干扰能力强,治理效果满足要求。
