查询词典 constant current

Academic preparatory school in current the city of London and diplomas is constant with the high class diploma course.

现有的伦敦城市学院的预科以及文凭和高级文凭课程不变。

The SMPS comprises a controlling unit for controlling switching frequency by changing the time constant of a switching unit depending on the current and reducing the amount of power supplied to the primary coil of the transforming element.

所述SMPS包括控制单元，用于通过根据电流来改变切换单元的时间常数并且降低被提供到所述变压元件的所述初级线圈的功率量，来控制切换频率。

Constant primary winding current independent of load level is inherent in the proposed system so that power could be transmitted from power source to load in a stable manner.

额定频率下系统一次侧线圈电流保持恒定而与负载大小无关，保证电能由电源向负载的稳定传输。

The flux hysteresis controller was ignored in the constant torque region and an improved method was proposed to make the estimation of torque easier.The proper stator voltage space vector was selected based on the output of the torque hysteresis controller and the sector which the current rotor flux locates in.

摘 要：针对无刷直流电机直接转矩控制中磁链观测困难、控制复杂等问题，提出了一种应用于无刷直流电机二二导通方式下的新型直接转矩控制方法：在电机基频以下调速时，略去了常规的磁链观测控制环节，改进了转矩计算方法，通过转矩滞环控制选择所施加的空间电压矢量。

A new brushless DC motor DTC scheme was studied to solve those problems associated with direct torque controlof brushless DC motor,such as difficulty to control flux and complexity to estimate torque.The flux hysteresis controller was ignored in the constant torque region and an improved method was proposed to make the estimation of torque easier.The proper stator voltage space vector was selected based on the output of the torque hysteresis controller and the sector which the current rotor flux locates in.

摘 要：针对无刷直流电机直接转矩控制中磁链观测困难、控制复杂等问题，提出了一种应用于无刷直流电机二二导通方式下的新型直接转矩控制方法：在电机基频以下调速时，略去了常规的磁链观测控制环节，改进了转矩计算方法，通过转矩滞环控制选择所施加的空间电压矢量。

The intension of reduce rank is that the time constant of current-ring is regulated to the best of minimum, and low frequency signal is equated to common proportional component.

磁悬浮系统降阶参数自校正控制，针对直接状态反馈法不足，使闭环系统的动态性满足调节时间和超调量等要求。

Because the formula of output voltage is the same as the one using other methods,the pulse width can be ascertained by choosing time constant based on the relation between voltage and current,and the proportional counter tube can be applied to different count ratio.

所得的输出电压的表达式与应用其他方法所得出的结果相同，因此可根据输出电压的波形与电路时间常数的关系，选择时间常数以确定输出脉冲宽度，使正比计数管适用于不同的计数率。

If frequency and pule width ratio of PWM are changed, the ripple of current, torque and so on are only influenced, when average value of armature circuit voltage is constant.

若保持电枢电路电压平均值不变，改变PWM的频率和占空比，只影响电枢电流和转矩等的脉动。

However, the application of this method is more various: How to transform current prices into constant prices in order to dispel the influence of price changes; how to quantitate human capital and bring it into the model.

对于技术进步的核算在方法上是一致的，但是具体的运用则比较多样：如何把当期价格转换为可比价格以消除价格变化的影响；如何把人力资本量化并带入模型。

The technique made full use of the characteristic of PR controller which can realize zero steady-state error in AC input signal in stationary frame. In the method, the active and reactive current component in the vector control strategy were transformed in the stationary frame to achieve the objective of keeping the DC-link voltage constant, adjusting the power factor and decoupling the active and reactive power. Compared with conventional double close-loop proportional integral controller, the PR technique is better in harmonic compensation without the complex rotating frame transformation and the couple or feedback voltage which is easily influenced by temperature and circuit parameters. The control algorithm is easy to be realized while the robustness and power quality is improved.

该方法充分利用了PR控制器能够在静止坐标系下对交流输入信号无静差控制的优势，将矢量控制策略下的有功电流和无功电流分量转换到静止坐标系下进行调节，实现网侧变换器维持直流电压稳定和调节功率因数的控制任务和双馈电机有功、无功功率的解耦控制，与传统的双闭环PI控制相比，该策略无需繁琐的坐标旋转变换，不存在受温度及电路参数影响的耦合项和前馈补偿项，且易于实现对系统低次谐波电流的补偿，减小了控制算法实现难度，提高了控制系统的鲁棒性和电网电能质量。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。