Fluid amplifier digital integrator

Fluid amplifier implementation into digital differential analyzing navigation syste

Digital Integrator for Fast Accurate Measurement of Magnetic Flux by Rotating Coils

A fast digital integrator (FDI) with dynamic accuracy and a trigger frequency higher than those of a portable digital integrator (PDI), which is a state-of-the-art instrument for magnetic measurements based on rotating coils, was developed for analyzing superconducting magnets in particle accelerators. Results of static and dynamic metrological characterization show how the FDI prototype is already capable of overcoming the dynamic performance of PDI as well as covering operating regions that used to be inaccessibl

ІНКРЕМЕНТНИЙ ЦИФРОВИЙ КВАЗІІДЕАЛ ІНТЕГРАТОР ЗАЯВКИ ПОПЕРЕДНЬОГО ПОТОКУ ОЦІНКИ КЕРУЮЧОЇ ІНДУКЦІЙНОЇ МАШИНИ

The performance of the speed controlled induction machine principally depends on the accuracy of the estimated flux. The proposed method compensates the error produced by the inherent problem in the “pure” integrator and measurement error. This paper describes the problem associated with a quasi-ideal digital integrator in particularly a modern DDA-type (Digital Differential Analyzer) – an incremental digital integrator (IDI). The paper essentially discusses the development of the approach to the total error correction of DDA-type IDI. It is an element for processing incremental digital input-output signals using DDA principles. The basic types of errors of the incremental digital integrator are presented and then the reasons for their appearance are examined. The differential equation dY=aYdx as an example the quantitative relation of errors is investigated. The IDI error from the analytical solution is not exceeding one increment (quant) of sub-integral function Y even during a very long interval of integration variable x. This means that the IDI becomes a practically ideal integrator. The suggested methods of correcting IDI errors can be applied in simulation, modeling, especially for dynamic systems control, etc. This method is easily applied in a DSP based induction machine control to estimate the flux.The performance of the speed controlled induction machine principally depends on the accuracy of the estimated flux. The proposed method compensates the error produced by the inherent problem in the “pure” integrator and measurement error. This paper describes the problem associated with a quasi-ideal digital integrator in particularly a modern DDA-type (Digital DifferentialAnalyzer) – an incremental digital integrator (IDI). The paper essentially discusses the development of the approach to the total error correction of DDA-type IDI. It is an element for processing incremental digital input-output signals using DDA principles. The basic types of errors of the incremental digital integrator are presented and then the reasons for their appearance are examined. The differential equation dY=aYdx as an example the quantitative relation of errors is investigated. The IDI error from the analytical solution is not exceeding one increment (quant) of sub-integral function Y even during a very long interval of integration variable x. This means that the IDI becomes a practically ideal integrator. The suggested methods of correcting IDI errors can be applied in simulation, modeling, especially for dynamic systems control, etc. This method is easily applied in a DSP based induction machine control to estimate the flux

Enhanced fast digital integrator for magnetic measurements

An enhanced Fast Digital Integrator (eFDI) was prototyped to satisfy the new requirements arising from current on-field exploitation of the previous Fast Digital Integrator in magnetic measurements for particle accelerators at CERN. In particular, the prototype achieves improved performance in terms of offset (5 ppm on 10 V fullscale), self-calibration accuracy (1 ppm of residual error), and data throughput (100 MB/s), by simultaneously preserving high-level signal-to-noise and distortion ratio (SINAD 105 dB at 10 Hz). In this paper, initially, the specifications, the design solutions, and the main features of the eFDI are illustrated. Then, the experimental results of the metrological characterization are compared with the CERN state-of-the-art integrator FDI performance in order to highlight the achieved improvements

A Fast Digital Integrator for magnetic measurements

In this work, the Fast Digital Integrator (FDI), conceived for characterizing dynamic features of superconducting magnets and measuring fast transients of magnetic fields at the European Organization for Nuclear Research (CERN) and other high-energy physics research centres, is presented. FDI development was carried out inside a framework of cooperation between the group of Magnet Tests and Measurements of CERN and the Department of Engineering of the University of Sannio. Drawbacks related to measurement time decrease of main high-performance analog-to-digital architectures, such as Sigma-Delta and integrators, are overcome by founding the design on (i) a new generation of successive-approximation converters, for high resolution (18-bit) at high rate (500 kS/s), (ii) a digital signal processor, for on-line down-sampling by integrating the input signal, (iii) a custom time base, based on a Universal Time Counter, for reducing time-domain uncertainty, and (iv) a PXI board, for high bus transfer rate, as well as noise and heat immunity. A metrological analysis, aimed at verifying the effect of main uncertainty sources, systematic errors, and design parameters on the instrument performance is presented. In particular, results of an analytical study, a preliminary numerical analysis, and a comprehensive multi-factor analysis carried out to confirm the instrument design, are reported. Then, the selection of physical components and the FDI implementation on a PXI board according to the above described conceptual architecture are highlighted. The on-line integration algorithm, developed on the DSP in order to achieve a real-time Nyquist bandwidth of 125 kHz on the flux, is described. C++ classes for remote control of FDI, developed as a part of a new software framework, the Flexible Framework for Magnetic Measurements, conceived for managing a wide spectrum of magnetic measurements techniques, are described. Experimental results of metrological and throughput characterization of FDI are reported. In particular, in metrological characterization, FDI working as a digitizer and as an integrator, was assessed by means of static, dynamic, and time base tests. Typical values of static integral nonlinearity of ±7 ppm, ±3 ppm of 24-h stability, and 108 dB of signal-to-noise-anddistortion ratio at 10 Hz on Nyquist bandwidth of 125 kHz, were surveyed during the integrator working. The actual throughput rate was measured by a specific procedure of PXI bus analysis, by highlighting typical values of 1 MB/s. Finally, the experimental campaign, carried out at CERN facilities of superconducting magnet testing for on-field qualification of FDI, is illustrated. In particular, the FDI was included in a measurement station using also the new generation of fast transducers. The performance of such a station was compared with the one of the previous standard station used in series tests for qualifying LHC magnets. All the results highlight the FDI full capability of acting as the new de-facto standard for high-performance magnetic measurements at CERN and in other high-energy physics research centres

Metrological Characterisation of a Fast Digital Integrator for Magnetic Measurements at CERN

A Fast Digital Integrator (FDI) was designed to satisfy new more demanding requirements of dynamic accuracy and trigger frequency in magnetic measurements based on rotating coil systems for analyzing superconducting magnets in particle accelerators. In particular, in flux measurement, a bandwidth up to 50-100 kHz and a dynamic accuracy of 10 ppm are targeted. In this paper, results of static and dynamic metrological characterization of the FDI prototype and of the Portable Digital Integrator (PDI), heavely used at CERN and in many sub-nuclear laboratories, are compared. Preliminary results show how the initial prototype of FDI is already capable of both overcoming dynamic performance of PDI and covering operating regions inaccessible before

A user configurable data acquisition and signal processing system for high-rate, high channel count applications

Real-time signal processing in plasma fusion experiments is required for control and for data reduction as plasma pulse times grow longer. The development time and cost for these high-rate, multichannel signal processing systems can be significant. This paper proposes a new digital signal processing (DSP) platform for the data acquisition system that will allow users to easily customize real-time signal processing systems to meet their individual requirements. The D-TACQ reconfigurable user in-line DSP (DRUID) system carries out the signal processing tasks in hardware co-processors (CPs) implemented in an FPGA, with an embedded microprocessor (μP) for control. In the fully developed platform, users will be able to choose co-processors from a library and configure programmable parameters through the μP to meet their requirements. The DRUID system is implemented on a Spartan 6 FPGA, on the new rear transition module (RTM-T), a field upgrade to existing D-TACQ digitizers. As proof of concept, a multiply-accumulate (MAC) co-processor has been developed, which can be configured as a digital chopper-integrator for long pulse magnetic fusion devices. The DRUID platform allows users to set options for the integrator, such as the number of masking samples. Results from the digital integrator are presented for a data acquisition system with 96 channels simultaneously acquiring data at 500 kSamples/s per channel

Linear Phase Second Order Recursive Digital Integrators and Differentiators

In this paper, design of linear phase second order recursive digital integrators and differentiators is discussed. New second order integrators have been designed by using Genetic Algorithm (GA) optimization method. Thereafter, by modifying the transfer function of these integrators appropriately, new digital differentiators have been obtained. The proposed digital integrators and differentiators accurately approximate the ideal ones and have linear phase response over almost entire Nyquist frequency range. The proposed operators also outperform the existing operators in terms of both magnitude and phase response

Study indicates fluid digital computation systems are feasible

Digital computation systems using fluid amplifiers are proven practical. The response speed is adequate for space applications and they are reliable in adverse environments. The systems may be feasible for satellite attitude controls and guidance computers for manned orbital stations

Class of Recursive Wideband Digital Differentiators and Integrators

New designs of recursive digital differentiators are obtained by optimizing a general fourth-order recursive digital filter over different Nyquist bands. In addition, another design of recursive digital differentiator is also obtained by optimizing the specified pole-zero locations of existing recursive digital differentiator of second-order system. Further, new designs of recursive digital integrators are obtained by inverting the transfer functions of designed recursive digital differentiators with suitable modifications. Thereafter, the zero-reflection approach is discussed and then applied to improve the phase responses of designed recursive digital differentiators and integrators. The beauty of finally obtained recursive digital differentiators and integrators is that they have nearly linear phase responses over wideband and also provide the choice of suitable recursive digital differentiator and integrator according to the importance of accuracy, bandwidth and the system simplicity