调波

The frequency band energy method based on the wavelet packets analysis is used for the feature extraction of signal.

同时，运用基于改进的小波包的频带能量法提取变频调速系统的故障特征，分析了小波包分解层次对特征量提取的影响。

From the view of torque controlling strategy, the relation between the torque controlling strategy such as the electric current feedback method、 PWM open loop method etc and the vehicle driving way is analyzed firstly, then the conclusion could be drawn that the PWM open loop method has more advantages than the electric current feedback method when they are both used in the same vehicle which is direct driving by hubcap motor. Secondly, based on the electric motor mathematic model and its experiment, a new permanent brushless dc motor phase electric current detector method in which a digital signal processor and single current sensor are used is introduced.

从转矩控制策略角度来看，分析了电流反馈法以及开环PWM电压调速控制方法与车辆的驱动方式关系，得出了电机驱动电压受限的情况下，无论是从对车辆的动力性能影响还是从对车辆的驱动要求来讲，开环PWM电压调速控制方法较电流反馈法更适用于以轮毂电机直接驱动方式的两轮电动车中；其次，根据电机的数学模型以及电机试验波形，提出了一种利用数字信号处理器以及单个电流传感器检测三相永磁无刷电机电枢电流的新方法，这种方法具有较强的适应性、实时性，它可以根据控制系统的要求，适时地提供所需电流数据，是目前许多文章关于无刷电机相电流平波的重要技术基础。

The control system includes detector circuit, protection circuit, control and man-machine interface circuit, which makes full use of DSP resources for high reliability and simplified the construction of system. The fifth section provides system software design, In order to read and maintain easy, a microprogramming modular is adopted. A new control strategy of Fuzzy voltage PWM combined Fuzzy angle control is realized for improving motor s working efficiency. At the same time, it simplify control model of SRM, reduce cost. At last, the result of experiment testify it, the electric machine gain success of simultaneous electrify two phase loop, the timing range is

第五部分为系统软件设计，采用模块化设计，增强了系统的可读性与可维护性；根据SR电机的特点，实现了模糊变角度电压PWM控制，避免了在单纯电压PWM方式下，电机高速时效率下降较大的缺点，也避免了在采用电流斩波与角度位置复合控制时方式转换所带来的弊端，同时也简化了控制，降低了成本；最后给出实验结果，实现了电机的双相稳定运行和良好调速，调速比达40：1。

Front man of a Minneapolis , Minnesota based blues , rhythm and blues , and jazz quartet .

前面的人一明尼阿波利斯，明尼苏达州为基础的蓝调，节奏和蓝调，爵士四重奏。

Under this direction, we developed a kind of inverter power supply, and the parameters are as follows:(1)the input of three-phase alternating current;(2)the output of sinusoidal wave;(3)the frequency of output: 5-25 kHz, which can be adjusted;(4)the voltage of output: 5-20 kV, which can be adjusted.

根据这个特点，我们研制了一种高频、高压的大功率逆变电源，参数如下：(1)三相交流输入；(2)输出正弦波；(3)输出频率：5～25kHz，可调；(4)输出电压5～20kV，可调。

Torre tried some lineup changes, hitting Rodriguez third and switch-hitter Jorge Posada fourth for the first time this season.

托瑞将打击顺序做了些变动，A-Rod调到第三棒，左右开攻的波沙达本季第一次调到第四棒。

The process of frequency fluctuation in the hydropower station with surge tank is impacted both by high-frequency water pressure wave and low-frequency water level fluctuation in surge tank.

在负荷变化和扰动过程中，设调压室水电站机组频率受到压力管道内水击压力波和调压室内水位波动的共同作用。

This chapter is the theory foundation of engineering analyses and design of this kind of new AC motor variable speed system.

本文针对目前交流调速系统设计实施及其应用推广中存在的问题，提出了一种基于优化PWM波和定子电压定向控制的新型交流调速系统。

The internal feedback chopper speed regulator is the preferred equipment of fan and water pump speed regulator.

内反馈斩波调速装置是风机水泵调速节能的首选设备。

The performance of radar's klystron affects directly the quality of radar echoes and operating cost, so the proper use and maintenance of klystrons are paid increasing attention presently.

雷达速调管的性能直接影响到雷达探测的回波质量及操作成本，因此速调管的使用维护也日益受到人们的重视。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。