锁环

We choose the TMS320VC5402, digital signal processor, as the computing unit, filtering the sampled signal, truncating the harmonic whose frequence greater than 2500hz, then we use the window-interpolation FFT algorithm to get the refined frequence, amplitude, phase of harmonic in sampled voltage and current, other parameter such as harmonic ratio, active power, reactive power, power factor, three-phase unbalance can be also computed base one the result of window-interpolation FFT.

选用TMS320VC5402高速数字信号处理器作为运算单元，先对采样信号进行数字滤波，去除50次以上谐波分量，然后应用加窗双峰插值FFT算法计算电压电流的各次谐波频率、幅值和相位，以及谐波含有率、有功功率、无功功率、三相不平衡度等各项电能指标，同时利用锁相环电路硬件跟踪电网频率以减小采样失步度。

Their advantages and disadvantages are discussed and a full digital asynchronous sampling method is devised to meet the integrating need by the decoder. Based on this method, we designed a hardware project, which can make the decoder independent from the sampling clock PLL .

针对解码器高集成化的需求，设计了全数字的异步采样方案；在此基础上提出了一种适合视频解码器的硬件实现方法，该方法采用全数字实现，摆脱了对片外锁相环的依赖。

To deal with the second type of variable speed system, a method which combines sliding mode decoupling control theory and Phase-Locked Loop technique is firstly applied to the induction motor's variable speed control.

针对第二类系统，本论文首次提出了将滑动模解耦控制理论与锁相环技术相结合的方案，应用于感应电机的调速控制系统。

On the basis of system structure and control principle, Maximum Power Point Tracking algorithm and the software design flowchart of the phase-locked loop are designed.

根据系统的结构和控制原理，设计出最大功率跟踪算法和锁相环的软件设计流程图。

The modeling strategy of mixed PLL is put forward, and an nonlinear model of the advanced PFD is achieved.

提出了数模混合锁相环的建模思想，建立了改进型电压泵PFD的非线性模型。

The structure of the all digital phase-locked loop is multiform.

全数字锁相环的结构形式是多样的。

A invariable -angle control circuit of parallel resonance converter which can get high precise control of inverter operating state is designed. Using the technique of phase-lock loop, the circuit implements automatic tracking to inverter operating frequency and constant control of capacitive power factor angle.

论文设计了能在频率自动跟踪的基础上实现高精度的逆变器运行状态控制的并联型逆变器定角控制电路，该电路采用锁相环技术，实现了逆变器工作频率的自动跟踪和容性功率因数角恒定控制。

A novel phase locked loop system used to realize real time phase synchronization under the condition of frequency variations of three-phase power system is presented.

本文提出了一种新颖的适用于三相电力系统在频率波动条件下的锁相环系统。

Considering strict and complex phase requirement, phase locked loop was used for precise phase shifting. Through Embedded logic analyzer the timing was sampled and verified. The driving timing generator of CCD camera with adjustable integral time was implemented on the CCD circuit board.Frame transfer CCD; Integral time ; Phase locked loop ; Embedded logic analyzer

考虑到CCD驱动时序复杂、相位要求严格，提出运用锁相环技术进行高频信号的精确移相，用嵌入式逻辑分析仪对时序进行采样验证，在CCD电路板上实现了积分时间可调的CCD空间相机驱动时序。

In this paper, some problems that have to be faced with in the application of SPLL to static synchronous compensator are analyzed, and two improvements of SPLL are proposed. The first one is removing the filtering function of lead-leg element into the prepositive delayed signal cancellation element to remedy the difficulty in deciding its parameters; the second one is directly taking the post-PI regulation output of q-axis voltage as error signal of phase to call off the forward integrating element.

分析了软锁相环应用于静止同步补偿器时面临的若干问题，并提出了2方面的改进方案：一是针对超前/滞后环节参数选取困难的问题，将其滤波功能转移到前置延时信号消除环节中；二是q轴电压经PI调节的输出直接作为相位的误差信号，减少了前向积分环节。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。