Leonīds Ribickis

Mutual couplings between EMI filter components

This paper deals with modeling of mutual couplings between passive EMI filter components: inductors and capacitors positioned on printed circuit board. 3D electromagnetic software CST MWS is used for the modeling. Three scenarios are considered: mutual couplings between two capacitors, mutual couplings between two inductors and mutual couplings between inductor and capacitor. Modeling results are verified experimentally using a vector network analyzer. Comparison of the measurement and modeling results shows that transfer coefficients and mutual inductance between two capacitors can be predicted accurately. However modeling of the mutual couplings between two inductors has the lowest accuracy.

Modeling of mutual coupling between inductors

This paper is devoted to EMI filter inductor modeling and mutual coupling modeling between two inductors positioned on PCB. 3D inductor models are developed and modeled in CST MWS. Comparison of inductors mutual coupling measurement and modeling results show that transfer coefficients can be predicted accurately. CST MWS has been used also to predict effective mutual coupling reduction techniques.

Proposed Piezoelectric Energy Harvesting in Mobile Robotic Devices

Mobile robots are being utilized increasingly in many applications, which include the exploration of relatively unknown environments including aerial, undersea, volcanic or even alien environments such as the plateaus and deserts of Mars where the Curiosity or Rover robot and others continue to explore. Due to their mobile nature these robots present us with many problems in the area of energy conservation. Mobile robots require more efficient energy saving techniques, due to their inherent self-sustained and self-constrained energy systems. The article is intended to inspire research among the power electronics community on the possibilities of new restorative energy techniques, including the small changes to infrastructure required to enable utilization of these methods. The restorative energy device, described herein, denotes a device that harvests collectable power from the general motion, weight and inclinations of the machine in both factory and remote locations.

Differential mode Il-type EMI filter modeling using CST MWS

This paper deals with modeling of differential mode Il-type EMI power filter using 3D electromagnetic field modeling software CST MWS. Two scenarios are considered: inductor is positioned in parallel or perpendicular to capacitors. Capacitor distance and PCB track layout is changed to verify software modeling precision and capabilities. Measurement and modeling results are in good agreement.

Design of human tracking robot utilizing pyroelectric sensor and analogue circuitry

A tracked crawler robot using body heat detection and a purpose built analogue tracking circuit is designed in this work. The infrared detection module consists of a single dual element pyroelectric infrared sensor. The drive and steering control system is designed using a single chip 74HCXX Quad 2-input NAND gate as the logic controller and providing constant forward propulsion whilst in real time adjusting to the subjects direction. Automatic tracking of animal or human subjects is the sole purpose of the design. The range has been limited to two meters, with a maximum range of five meters. Modification of the pyroelectric sensor enables detection of both left and right movement. The robots ability to follow human and animal motion has been achieved. Visually observed results show the robot is able to drive, turn and detect human and animal motion and can work reliably. The design is able to be utilized using a microprocessor or as a highly responsive analogue unit making it both adaptive and flexible.

High efficiency modular DC-DC power converter for adaption to industrial & hybrid robotics

The purpose of this paper is to address current issues in industrial robotics applications and to address also the current trends occurring in the industry regarding smaller mobile units in factory and external manufacturing processes relating to the battery powering of robotics devices. Specifically, we shall concentrate the efforts herein on “Mobile Industrial Robotics”. The paper touches briefly on problems associated with both definitions of industrial robots and problems associated with power supply sources of mobile industrial robotics and provides an outline of future work with appropriate solution for smaller mobile industrial mobile units operating in the variable input range of 24V to 48v and outputs in the range of 3.3V to 12V @ 20A in three stages. The project required a fast, turn-key solution which did not allow for a “design from scratch” solution and so detailed herein is suitable design produced in other sectors and relating the details, design process, modelling and examination of a successful and efficient high current DC to DC switch mode power supply. Parameters have been adjusted to our own preferences in the design considerations regarding “Industrial Service Hybrids” [1] (ISH)1. Other design issues are under assessment and shall be included as the project moves forward.

Matrix frequency converter conducted and radiated emissions

Matrix converter inherently exhibits sinusoidal input current waveforms and has less stressful output voltage waveforms, but it is causing problems with conducted and radiated emissions. This paper deals with matrix converter emitted disturbances from point of view of electromagnetic compatibility (EMC) standard EN61800-3 and allocates the sources of undesirable emissions.

Latvian Practices for Protecting Water and Wastewater Infrastructure

The Republic of Latvia has promulgated a number of laws that govern the national response to emergencies in water and wastewater.