Voltage-Ratio Measurement with a Precision of Parts in 109 and Performance of Inductive Voltage Dividers

The causes of error in inductive voltage dividers are examined in detail, and equations are developed from which the voltage ratios may be predicted with an uncertainty not exceeding 1 part in 108. Experimental methods for measurement of the voltage ratios to an accuracy of 2 parts in 109 of the input voltage vector are fully described, together with techniques by which the constituent parts of the overall error may be isolated. An improved method of winding decade inductive dividers is also described and specifications are given for multidecade devices in which the errors predictably will not exceed 1 part in 108 at 400 Hz or 5 parts in 108 over the whole frequency range 40 to 1592 Hz.     

带量程扩展器的工频感应分流器的校准与应用

工频电流比较仪准确度通常达到0.001级以上,用于检定0.01级及以上的标准电流互感器.电流比较仪的一次电流和二次电流都采用分段串并联结构,变换一个电流比需要改动多个连接片.由于电流比相当多,检定时换接线工作量大,容易出错.工频感应分流器准确度可以达到10-6量级,只要选择适当的抽头就能得到需要的电流比,可以大大减轻检定工作量.如果使用零磁通电流互感器作为量程扩展器,就可以覆盖电流互感器的全部量程,与电流比较仪共同用于精密电流互感器的检定.     

The Stray-Capacitance Equivalent Circuit for Resistive Voltage Dividers

An equivalent circuit for the stray capacitances of resistive voltage dividers is proposed. The parameters of the equivalent circuit are determined from the electrostatic field of the divider. The stray-capacitance equivalent circuit for a 12.75-k? divider has been determined and its step-response has been computed. The computed stepresponse agrees well with the measured step-response.     

On the Output Resistance of Self-Checking Voltage Dividers

This paper deals with the computation of the variable output resistance of Cutkosky's self-checking binary voltage divider. For an N-bit divider, the maximum output resistance was found to increase with N at the rate of N/9 times the divider's characteristic input resistance. To increase the divider's resolution while limiting its output resistance, a binary potentiometer as a termination is suggested.     

电压加法在直流高压分压器电压系数测量中的应用

用标准分压臂插入法测量直流分压器的误差 ,不确定度难以达到 10 - 4量级。到目前为止 ,高准确度的直流高压分压器的电压系数 ,只能用影响量分项评估方法综合 ,不能给出实际值。应用直流电压加法技术 ,可用计量测试手段实测直流高压分压器在各个工作电压下的误差和不确定度。对 5 0 0kV等级测量结果的不确定度可达到 1 1× 10 - 5。     

Adapted Technique for Calibrating Voltage Dividers of AC High-Voltage Measuring Systems

MAPAN - This paper presents an adapted technique to calibrate the AC voltage divider of AC high-voltage measuring systems up to 200 kV at the Egyptian National Institute of Standards. Two...     

A Method of Calibrating Standard Voltage Dividers up to 1000 V

A method of calibrating a resistive voltage divider for voltage ratios of 1000 V/10 V and 100 V/10 V with an uncertainty at the level of 10⁻⁷ is developed. The method enables a calibration to be carried out at the working voltage of the divider and can be used to calibrate a transportable voltage ratio standard when carrying out CCEM-K8 key comparisons.__________Translated from Izmeritel’naya Tekhnika, No. 4, pp. 52–57, April, 2005.     

多二次绕组电磁式电压互感器的误差测试

分析电磁式电压互感器,当具有多个独立的二次绕组时,多个绕组由于采用同一个铁心,通过试验说明各个绕组的实际误差会收到另外绕组所带负荷大小的影响;阐述多绕组电磁式电压互感器的检验方法及有关注意事项。     

Low-Frequency One-Step Inductive Voltage Divider with Ratio up to 1: 1000

The advantages and disadvantages of one-step and multidecade inductive voltage dividers at low frequencies, i.e., frequencies below 10 Hz, are discussed. By electronically decreasing the magnetizing current of one-step dividers and by use of a special design, errors become very small. The construction and the calibration of such dividers is described. Preliminary test results of dividers of the autotransformer and the isolating transformer type show in-phase errors of 10-8 (ratio 10-2) and 10-7 (ratio 10-3) of output. Output resistances are in the 10-3 ? range. The input resistances are about 109 ? at 81/3 Hz.     

Calculating the Amplitude Error of an Inductive Voltage Divider

A technique is proposed for analytically determining the amplitude error of a decade voltage divider, taking the stochastic properties of the braid into account.     

1000V多盘感应分压器标准建立

中国计量科学研究院研制了一台1000V多盘感应分压器标准装置,用作工频1000V电压比例标准。该装置使用了一种基于互感器注入的误差补偿技术,可准确提供从1×10^-8到1的宽范围比例出。感应分压器的误差校验使用了包含三同轴屏蔽技术的改进型参考电势增量法,并设计了多比例参考互感器以便对感应分压器进行整体校验。所研制的感应分压器准确度优于1×10^-7,校准结果不确定度小于2×10^-8。     

An Optimized Design for a Low-Frequency Inductive Voltage Divider

A theoretical investigation of the causes of error in multidecade two-staged inductive voltage dividers (IVD) has been made and from this an optimized design for the frequency band 10-400 Hz has been evaluated. A three-decade divider rated at 0.6 times frequency has been constructed and calibrated and the errors of voltage division do not exceed the design limits of 5 × 10-9 of input.     

一种新型的交直流差可计算电阻

提出了一种新型交直流差可计算电阻方案,并建立了数学模型,推导出此种结构的电磁场计算公式,进而计算出此种新型电阻在0～100 kHz内的交直流差.与"同轴线型"、"四回线型"和"八回线型"等方案相比,该结构具有较小的交直流差和较好的机械稳定性.此外,文中提出的结构更为紧凑,因而可使用线径较粗的电阻丝,电阻的自发热问题不明显,不需要使用浸入硅油等散热措施,电阻值的细微调整也比较容易.     

基于改进型两次平衡对检法的感应分压器自校准方法

介绍了参考电势变压器和指零仪变压器设计原理,分析了屏蔽间泄漏对测量结果的影响;对常规两次平衡参考电势对检法进行了改进,使零平衡和段平衡测量过程中,参考电势和测差电路均可实现等电位保护;对自校准方法进行了推导,校准结果仅与段平衡和零平衡时锁相放大器测量的电压差值相关,与参考电势变压器、指零仪变压器、辅助变压器等的误差无关,屏蔽间泄漏的影响也得到消除。对1kV感应分压器进行了校准实验,并对校准结果进行了测量不确定度分析,其相对扩展不确定度的评估结果为5.4×10^-8(k=2)。     

A 1-MHz Binary Inductive Voltage Divider with Ratios 2n to 1 or 6n dB

A voltage divider with ratios of 2n to I or 6n dB is obtained by cascading n binary dividers, each having a voltage ratio of 2 to 1. A theoretical analysis results in an expression for the ratio error. Several techniques are given for reducing this error. A voltage comparator is described for eliminating errors due to external loading of the divider. An experimental cascaded binary divider with a total of 42 dB in seven 6-dB steps is described. The attenuation of the divider was measured with a precision waveguide-below-cutoff attenuator at 1 MHz. The divider and attenuator values agree within the uncertainty of the attenuator and measuring system at 1 MHz.     

An International Comparison of Inductive Voltage Divider Calibrations at 400 and 1000 Hz

The establishment and maintenance of the highest possible order of accuracy for the measurements of voltage ratio and phase angle are responsibilities of the national laboratories. This paper reports the results of an international comparison of a seven-decade inductive voltage divider by the United States National Bureau of Standards and the National Research Council of Canada. The calibration techniques used in each laboratory are discussed in detail, and the results of calibration at 400 and 1000 Hz are compared. The accuracies of measurements are within 0.1 ppm of input for voltage ratio and 1 (setting of dials)1/2 microradians for phase angle.     

A Converter of the Parameters of Capacitive and Inductive Pickups into a Voltage

A method of constructing converters with strobing is considered. Practical examples are given.     

A Generating Voltmeter with Calculable Voltage-Current Ratio for Precise High-Voltage Measurements

A new design of a generating voltmeter with a rotating measuring electrode system is described. It is based on an arrangement of eccentric circular cylinder electrodes. Hence an essential advantage of the voltmeter is a calculable voltage-current ratio provided the rotation frequency is known. Moreover the electrode arrangement is self-shielding. For these reasons, in principle, no calibration is necessary. The properties of the voltmeter are discussed theoretically. Two practical laboratory devices are presented. Prospects for future development are discussed.