Compact Reconfigurable Input Output Research Articles

A Real-Time Synchrophasor-Based Zone-3 Supervision of Distance Relays Under Load Encroachment Condition

This paper deals with the implementation of a real-time supervisory protection algorithm to avert the mal-operation of third zone element of distance relays during load encroachment. The proposed supervisory algorithm controls the operation of the backup zone (Zone-3) of distance relays by analyzing the synchrophasor data obtained from the phasor measurement units (PMUs) located throughout the power system network. The combination of the inherently higher delay time of Zone-3 element and the latency associated with PMUs to communicate information to the central control center makes the algorithm suitable for transmission line protection. The superiority of the proposed method is verified by conducting extensive real-time experiments on a laboratory model for a 400-km extra high voltage transmission line and implementing the protection algorithm on the LabVIEW platform at the System Protection and Control Centre. PMUs have been realized using National Instruments (NI) Compact Reconfigurable Input–Output embedded controllers, and the synchrophasor estimation algorithm is deployed using LabVIEW field-programmable gate array software. The results obtained from the experimental setup validate the viability of the proposed algorithm for the real-time implementation.

Design and Development of CRIO based Data Acquisition and Control system for High Voltage Bushing Experiment

Experiment of Prototype High Voltage Bushing (PHVB) is an important step to validate the design of HV bushing (HVB) of DNB for its electrostatic performance. The experiment is performed considering scaled down configuration DNB HVB with similar operating parameters and maintaining comparable electric stresses. Applied voltage is restricted up to 60 kV considering it’s scaled down configuration. To automate the entire experimental process and acquiring important experimental data for post analysis, a dedicated Data Acquisition and Control System (DACS) is designed. CRIO (compact reconfigurable input output) is a rugged, small sized hardware platform which combines the power of real time processor and FPGA bus. NI CRIO is now widely used as a controller for small scale experiments. For ensuring smooth control operation of the experiment; NI CRIO was selected as the controller for DACS of PHVB. In this paper the technical details of DACS design, implementation and test results are discussed.

Embedded control systems for gyrotrons applications based on NI solutions

The Swiss Plasma Center is involved in the development and the operation of gyrotrons for fusion application (TCV tokamak, W7-X, ITER, DEMO) as well as for basic science applications such as Nuclear Maggnetic Resonance (NMR) spectroscopy. In this framework, embedded control systems based on National Instrument (NI) compact Reconfigurable Input Output (cRIO) and compact Data AcQuisition (cDAQ) offer versatile solutions for dedicated applications. Three specific developments are briefly presented and discussed here. First, a complete control system based on cRIO material has been implemented in a Modulator Power Supply. Second, the development of a compact system, based on a cDAQ solution used for the characterization of the RF losses on the various gyrotron components. Third, the installation of a whole control system for a Dynamic Nuclear Polarization (DNP/NMR) gyrotron dedicated to non-specialist gyrotron users.The flexibility given by these compact control systems and acquisition could offer multiple solutions in many applications for fusion research.

Design and development of a model free robust controller for active control of dominant flexural modes of vibrations in a smart system

Real physical vibrating smart systems exhibit a lot of nonlinearities in their dynamics. Undesirable vibrations, particularly in the regions of first as well as second resonance, play a very important role in deteriorating the stability of the system as well as its operational efficiency. The work presented in the paper focuses on an analytical technique of mathematical modeling of a vibrating piezoelectric laminate cantilever beam which is considered to be the smart system. The natural frequencies of the vibrating smart system are determined from the ANSYS simulation studies and experimentally, it is found that the vibrations induced voltage is maximum at the first followed by the second natural frequencies. Hence, the smart system is modeled analytically through finite element technique using the Euler–Bernoulli beam theory for the first two flexural modes of vibrations. To account for the possible nonlinearities, a suitable robust controller is designed based on sliding mode technique. Simulation studies on the developed analytical model indicated a high performance of the designed controller in controlling the vibrations at first and second resonance regions. Also, the designed controller was found to be effective in its operations when the excitation varied over a large range covering the first two natural frequencies. In the final stage, the designed robust controller was successfully prototyped on a Field Programmable Gate Array (FPGA) platform using LabVIEW coupled with Compact Reconfigurable Input Output (cRIO-9022) controller configured in its FPGA interface mode and the resulting robust FPGA controller successfully controlled the occurring system vibrations.

Parametric modeling and FPGA based real time active vibration control of a piezoelectric laminate cantilever beam at resonance

The operational efficiency and life of mechanical systems/structures depends to a large extent on their vibration control. Continuously occurring vibrations on the systems can cause fatigue and the effects of these vibrations are particularly severe if they occur at a frequency matching with that of the concerned system’s natural frequency – a stage called resonance. This paper focuses on achieving active vibration control of a smart cantilever beam at its first resonant frequency as it is at this stage that maximum damage to the system performance is expected. The smart system is modelled in the parametric domain using finite element modeling techniques and the obtained model is validated through experimental means. The active vibration control is achieved by employing two control algorithms namely – output feedback and error based control through general purpose operating system (LabVIEW on Windows 7) as well as in real time operating system (LabVIEW FPGA coupled with compact reconfigurable input output modules) and the performances are compared thereby justifying the importance of the deterministic and reliable real time control over the usual PC based control in experimental studies.

Real Time Control of Active Ankle Foot Orthosis Using Labview and Compact-Reconfigurable Input Output

The main aim of this research is to develop a standalone embedded system for the control of dorsiflexion or plantarflexion movement using surface Electromyography (sEMG) signals in an active ankle foot orthosis. Active ankle foot orthosis is used to support or restore the complex ankle foot movements of the subjects with drop foot gait. Dropfoot, a loss of use of the muscles that lift the foot, caused by stroke, cerebral palsy (CP), multiple sclorosis (MS), or neurological trauma. The control system for active ankle foot orthosis is developed using compact-RIO in FPGA mode. The LabVIEW code developed for the control of the motor is deployed on to the compact-RIO. The proposed control system consists of sEMG electrodes, National Instruments Compact- Reconfigurable Input Output (NI cRIO), NI Analog Input Module, Digital output module, motor driver and a DC motor. NI compact-RIO is a programmable automation controller which uses analog and digital I/O modules which acquires the required data and controls the hardware. Compact-RIO is programmed by using NI LabVIEW.