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931.
文中对蒸汽锅炉补水泵采用变频调速控制和PID调节作了较为详尽的描述,选择了锅炉水位测量仪表,给出了相应的主电路和控制电路原理图,并设置了变频器的相关参数。实际运行表明,设备稳定可靠,达到了预期效果,可推广应用。 相似文献
932.
933.
This paper proposes a novel switching method with the neutral-point voltage control in a single-phase neutral-point-clamped three-level inverter (SP-NPCI) used in photovoltaic systems. A proposed novel switching method for the SP-NPCI improves the efficiency. The main concept is to fix the switching state of one leg. As a result, the switching loss decreases and the total efficiency is improved. In addition, it enables the maximum power-point-tracking operation to be performed by applying the proposed neutral-point voltage control algorithm. This control is implemented by modifying the reference signal. Simulation and experimental results provide verification of the performance of a novel switching method with the neutral-point voltage control. 相似文献
934.
以某风冷冷冻柜为研究对象,分别从毛细管长度、制冷剂充注量、频率变化三个方面试验分析毛细管对制冷系统性能的影响。试验得出最佳毛细管长度为650mm;最佳充注量为1060g;系统高能效比的频率范围在20Hz～60Hz之间,对于在稳定工况下运行的机组,变频并不能起到很好的节能效果。通过标准毛细管和使用一定时间后的被测毛细管的对比分析,改变电流模拟分析系统启停,得到以库中央温度和冷凝器中央温度为代表的影响系统性能的变化曲线。实际运行中可通过监测库中央温度、冷凝器中央温度、压缩机吸气和排气温度、压缩机上下表面温度,与标准毛细管对比就可准确判断出系统运行状态是否正常。 相似文献
935.
Organic-based complementary inverter could be a key component in future flexible and portable electronic products, which require low-power operation, high operating stability and flexible compatibility at the same time. A simple method for making excellent Al2O3 gate dielectric is developed toward the target, and it is a low-cost solution process with a low annealing temperature compatible with plastic substrates. Utilizing the Al2O3 dielectric, both p-type and n-type low-voltage organic field-effect transistors (OFETs) are realized. The device operating voltage is down to ±3 V, and the On/Off ratio is up to 106. The hole and electron field-effect mobilities are 2.7 cm2/V and 0.2 cm2/V, respectively, and the subthreshold swing is as small as about 110 mV/decade. The high quality of the Al2O3 dielectric results in high operating stability of the devices. The p-type and n-type OFETs are integrated to achieve a low-power complementary inverter with a large gain, which can be successfully fabricated on a flexible substrate. 相似文献
936.
The use of low-strain sensors based on complementary inverters for the detection of tensile strain has been verified. Complementary inverter-type gauge circuits are comprised of a strain-sensitive bendable C26H16N2(heptazole)-based organic field-effect transistor (OFET) and a relatively strain-insensitive N,N′-ditridecyl-perylene-3,4:9,10-tetracarboxylic diimide−C13(PTCDI-C13)-based one, as p- and n-channels, respectively. This study complementary circuit showed a voltage gain of more than 10 and a relatively low static current (below 0.2 nA) at a supplied voltage of 5 V, without strain application. Using the elastic and reversible response to the tensile strain in the heptazole p-channel, the complementary inverter-type gauge circuit enabled us to achieve a high gauge factor of 90% and to measure an extremely low strain level of 0.02% under subnanowatt power dissipation conditions during the strain-sensing operation. This ultrasensitive and low power-consuming strain gauge could be highly beneficial for portable and large-area strain sensors, one of the most critical components of mobile applications. 相似文献
937.
This paper presents static and dynamic studies of a new CMOS realization for the inverting second generation current conveyor circuit (ICCII). The proposed design offers enhanced functionalities compared to ICCII circuits previously presented in the literature. It is characterized by a rail to rail dynamic range with high accuracy, a low parasitic resistor at terminal X (1.6 Ω) and low power consumption (0.31 mW) with wide current mode (3.32 GHz) and voltage mode (3.9 GHz) bandwidths.Furthermore, a new MISO current mode bi-quadratic filter based on using ICCII circuits as active elements is proposed. This filter can realize all standard filter responses without changing the circuit topology. It is characterized by active and passive sensitivities less than unity and an adjustment independently between pole frequency and quality factor. The operating frequency limit of this filter is about 0.8 GHz with 0.674 mW power consumption.The proposed current conveyor circuits and bi-quadratic filter are tested by TSPICE using CMOS 0.18 µm TSMC technology with ±0.8 V supply voltage to verify the theoretical results. 相似文献
938.
《Electronics and Communications in Japan》2017,100(3):10-18
Recently, high‐speed searching for the most similar reference data out of the database is needed for data compression, image recognition, network control, and others. However, it takes much time to search for data with software, or hardware using conventional memory. Associative memory has been developed as a high‐speed searching device. In this paper, we propose a minimum Hamming distance search associative memory using neuron CMOS inverters. The proposed associative memory is less affected by initial charge and a change of threshold voltage of neuron MOS transistors than conventional neuron CMOS circuits. The proposed circuit also makes searching speed higher by using fully parallel processing. We confirmed that the proposed circuit can be realized expected results by simulation, and experiment using test chip. 相似文献
939.
940.
单相光伏并网逆变器通常采用双闭环控制和电网电压前馈控制的策略,其中双闭环的外电压环为采用PI恒压控制逆变前直流侧电压,分析比较了准比例谐振调节和PI调节两种电流内环的输出外特性,通过对电流内环采用准比例谐振控制的控制系统进行分析建模,建立了逆变器的单相并网仿真模型。仿真结果显示电流内环采用准比例谐振控制能实现并网电流的无静态误差控制,并减小电网频率偏移对并网电流的影响。仿真及实验得到的输出正弦电流波形良好,基于该并网控制策略的光伏逆变器能以高功率因数向电网发电,动态响应快、鲁棒性强、跟踪精度高、并网电流的THD明显优于传统方法,从而验证了改进后模型的可行性和实用性。 相似文献