Thomas Spiegel

Bio: Thomas Spiegel is an academic researcher from German National Metrology Institute. The author has contributed to research in topics: Multimeter & Signal. The author has an hindex of 2, co-authored 11 publications receiving 15 citations.

AC–DC Disk Resistors Made of Surface Mount Components

Abstract: Disk resistors are widely used in micropotentiometers up to frequencies in the radio frequency range. They offer very small AC–DC differences but the permissible power dissipation is quite small. Also, the resistance value is poorly defined due to the lack of four-terminal connections. This can be overcome by newly designed disk resistors made of surface mount device components [1]. They are also well suited as AC–DC current shunts for currents up to several amperes.

Verification of low frequency ac–dc transfer differences of thermal converters using sampling with sine-wave fit

Abstract: Thermal converters show significant ac–dc transfer differences at low frequencies due to nonlinearities of the heat transport mechanism and of the thermal-to-electric conversion. It is assumed that the ac–dc transfer differences at low frequencies are proportional to the input power. We have proved this assumption by an independent method with sampling techniques. A novel approach based on sine-wave fitting is used to calculate the RMS value of the sampled signal from the samples. It makes use of the low noise in a metrological environment. Expanded uncertainties in the order of 1.2 μV/V have been achieved.

Real power measurement using a thermal converter

Abstract: In this paper, a new application of thermal converters is presented which allows energy, power and rms measurement without the need to substitute the measurement signal with a dc signal as performed in ac–dc transfer. Using a mathematical model of standard planar multijunction thermal converters (PMJTCs), the effective power acting inside the heater of the PMJTC is calculated from the output signal of its thermocouples. Due to the underlying physical principles, this method not only allows the calculation of the rms value of sinusoidal signals but also the average power and absolute energy contained in non-sinusoidal, non-periodic and even non-stationary signals, as appearing in the characterization of energy harvesters.

AC-DC disk resistors made of surface-mount components

Abstract: Disk resistors are widely used in micropotentiometers up to frequencies in the radio frequency (RF) range. They offer very small AC-DC differences but the permissible power dissipation is quite small. Also the resistance value is poorly defined due to the lack of four-terminal connections. This can be overcome by newly designed disk resistors made of surface mount (smd) components. They are also well suited as AC-DC current shunts for currents up to several amperes.

AC-DC current transfer standards suitable for use below 1 mA and up to 1 MHz

Abstract: Traceability for AC currents below 1 mA is needed to calibrate calibrators and multimeters at frequencies up to at least 100 kHz. Since the sensitivity of thermal convertors is not sufficient, only transfer standards using amplifiers are suitable. A newly designed combination of an amplifier and a shunt works at higher frequencies up to 1 MHz as well.

OOK power model based dynamic error testing for smart electricity meter

Abstract: This paper formulates the dynamic error testing problem for a smart meter, with consideration and investigation of both the testing signal and the dynamic error testing method. To solve the dynamic error testing problems, the paper establishes an on-off-keying (OOK) testing dynamic current model and an OOK testing dynamic load energy (TDLE) model. Then two types of TDLE sequences and three modes of OOK testing dynamic power are proposed. In addition, a novel algorithm, which helps to solve the problem of dynamic electric energy measurement's traceability, is derived for dynamic errors. Based on the above researches, OOK TDLE sequence generation equipment is developed and a dynamic error testing system is constructed. Using the testing system, five kinds of meters were tested in the three dynamic power modes. The test results show that the dynamic error is closely related to dynamic power mode and the measurement uncertainty is 0.38%.

AC–DC Disk Resistors Made of Surface Mount Components

Abstract: Disk resistors are widely used in micropotentiometers up to frequencies in the radio frequency range. They offer very small AC–DC differences but the permissible power dissipation is quite small. Also, the resistance value is poorly defined due to the lack of four-terminal connections. This can be overcome by newly designed disk resistors made of surface mount device components [1]. They are also well suited as AC–DC current shunts for currents up to several amperes.

Low-Frequency AC–DC Differences of a Series–Parallel Circuit of Thermal Converters

Abstract: A series–parallel connected thermal converter (TC) arranged in an $m \times m$ matrix of a heater and an $m^{2}$ -series connected thermocouple are proposed to reduce low-frequency ac–dc differences. The electrical circuit theory on the proposed circuit suggests that the low-frequency ac–dc differences of $m \times m$ series–parallel connected TCs decrease in proportion to 1/ $m^{2}$ , avoiding any degradation in the output voltage and a time-consuming measurement. A significant reduction of the low-frequency ac–dc differences by a factor of 10 for the proposed circuit is experimentally demonstrated with no decrease of the output voltage, which is consistent with the electrical circuit theory.

AC-DC disk resistors made of surface-mount components

Abstract: Disk resistors are widely used in micropotentiometers up to frequencies in the radio frequency (RF) range. They offer very small AC-DC differences but the permissible power dissipation is quite small. Also the resistance value is poorly defined due to the lack of four-terminal connections. This can be overcome by newly designed disk resistors made of surface mount (smd) components. They are also well suited as AC-DC current shunts for currents up to several amperes.