Radu Pentiuc

The mathematical model of a stand measuring the torque of the termobimetal actuators

Evaluation the torque generated by the actuator systems is a problem in that the forces obtained have small values. The experimental stands used to evaluate the performance of an actuator must allow an easy adjustment of the measuring equipment to the characteristics of the tested system. The paper presents the mathematical model of a quadrilateral mechanism used in a stand designed to measure the torque of a thermo-bimetallic actuator. The accurate evaluation of geometry of the force transmission mechanism allows the improvement of measurement accuracy for low and very low values obtained in the first part of the use of the actuator.

The modeling and simulation of the synchronous generators connection to the power system

The paper presents modeling and simulation programme of the synchronize conditions for synchronous generator in the thermal power plants. The programme is utilized for educational purposes in the laboratory “Electrical Section of Power Plants” for the conditions study and the practical skill moulding to the thermal power units interconnected. Are studied the synchronize conditions and the admissible deviations for the TH-60-2 turbo-generator of 60 MW which equipping the combined heat and power plants majority of Romania.

Determining the amount of electricity generated in high efficiency cogeneration for the access to the support scheme through green certificates

In case of the combined heat and power plants, heat supplied to consumers it has a decisive influence to qualified of electricity generated in high efficiency cogeneration. The paper present the options for determining the amount of useful heat delivered to consumers considering the specific operating conditions of the cogeneration unit with ORC technology and biomass fuel.

Integration of thermal energy storage systems for improved efficiency and flexibility of the combined heat and power plants of medium and small power

Demand for useful heat it is the essential condition in the qualification of electricity production in high efficiency cogeneration. A solution to provide the demand for useful heat and compensation of load variations over time it is the storage of thermal energy. The paper presents the technical and economic analysis of the heat storage systems use for a cogeneration unit with ORC technology and biomass fuel

Optimisation of operating mechanism and drive system for medium voltage circuit breakers

This paper identifies several directions to improve the performances of the operating mechanism for medium voltage circuit breakers in order to get variable moving characteristics of the moving contact adjusted to the value of the switching current. Different drive solutions currently used in the operation of vacuum circuit breakers and SF6 were analyzed comparatively, as well as the performances they have to meet depending on the application. The solution proposes the use of a system with a microprocessor able to independently control the operation of moving contacts by stepper motors and the acquisition of the circuit breaker functional parameters.

Power quality system analysis on embarked systems

The naval installation has a series of particularities compared to the industrial ones from the ground. Their dimensions are small, lightweight, should be functioning safely, efficiently at lower operating costs to enroll in the overall cost of the ship, to keep the plant competitive. A naval installation includes electronic equipment and the electrical equipment of the layout is loaded close to the maximum power. Therefore, naval equipment is a source of harmonic or inter-harmonic disturbances, which cause additional losses, unfavorable.

Energy recovery of municipal solid waste for combined heat and power production

The Municipal Solid Waste (MSW) from the household, commercial or industrial represent materials with significant energy value. The directives of European Union (EU) discourage landfilling of waste and promotes their recycling and recovery. Until the present, in Romania there are no plants in operation for the municipal waste incineration. The municipal waste disposal is carried out solely through landfills. The paper presents energy recovery potential of municipal solid waste and the possible contribution to the demand for heat of the city Suceava.

Wider generality relation in the road lighting calculation

The design of the outdoor lighting is based on the point-by-point method to estimate the direct component of the illuminance and it has a high complexity. This complexity is higher as the spatial repartition of the luminous intensities is more asymmetrical and as the more random is the position between the luminaire and the visual task. At the present, the lighting-domain specific software helps for quick and precise calculus, using some complex formulas with different degrees of generality. The present paper proposes a new way in applying the point-by-point method, by a different estimation of the zenith (a) and azimuth (P) angles. It uses an orthogonal reference system placed in an arbitrary point, which is transformed by successive rotations into a more convenient one. Using this new method, the resulted relations have a higher generality and the calculus time is shorter, especially in the very complex systems. Even seem apparent complicated, the obtained formulas are a result of the calculus with rotation matrices and can be easy implemented into the software. Moreover, they can be easily customized for any specific conditions.

Concepts and models for design and simulation of distributed control systems for future power grid

This paper presents our vision on developing a software tool for modeling and simulating the intelligent behavior of the future power grid. Modeling approaches based on function blocks and holonic concepts are proposed for the intelligent control entities, designed to interact with each other to optimize the operation of the grid in relation to the distribution of power, integration of equipment and failure recovery. IEC 61850 specifications are selected as reference model for communications.

Indices for the power quality monitoring in the Romanian Power Transmission System

The power quality monitoring is one of the modern issues of the electricity market. The permanent monitoring of power quality parameters is used to verify the contractual requirements presented in regulations. There is a need for common power quality indices that are the result of synthesis, reducing or extracting from a large volume of power quality measurement data. The values for these indices have to be compared to the limits described by the national regulator. The paper presents in a synthetic manner, indices for the continuity and power quality monitoring in the Romanian Power Transmission System. Are identified the main causes of worsening power quality in some areas of the transmission system.