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Sigma-delta modulation is a method of constructing the radio frequency linear power amplifier with the using non-linear components. It can significantly simplify the structure of the power amplification path, which in this case shall operate as one-bit DACs. The preliminary modeling of potential different variants of the output stage in classes E, F, D (voltage switching and current switching) and...
In this paper the switched reluctance generator (SRG) is explored considering the improvement of its efficiency. This machine generates a DC power that is directly related to input driving parameters. Simulation results are presented bringing a case study of parametric regression to track the best efficiency for any input parameters: excitation voltage and turn off angle. A method known as parametric...
This paper gives a new approach for optimizing the total power output of a hydroelectric power station by analyzing the characteristics of efficiency function. It proofs the maximum total power supply. Under the constant head of the river, keeping each generator the same flow rate is the efficiency optimization, and the switch points are at the same efficiency points of different operating methods.
Integration of digital RF transmitters and digital power amplifiers (DPA) is becoming of great interest for systems-on-chip (SoCs) available in nanometer technologies [1]. Small and high-speed switching devices directly benefit switching power amplifiers in achieving peak power with high peak efficiency. However PA back-off efficiency remains a big challenge in high-data-rate systems with large peak-to-average...
This paper analyzes a compensating control strategy for stable energy output of the novel direct drive wave energy generator. We propose a compensating control structure based on the unstable second-order linear dynamics for the direct drive wave energy generator, and the dynamics are derived by the on-line system identification method. In the control strategy, we design a servo compensator located...
In this paper we show how to build an economically optimal feedback control strategy for the re-dispatch of electricity generation. We assume that the operator steers production in a set of controllable power plants by altering the active power set-point of each generator, within a set of predefined set-points. The operators strategy will be based on balancing the operating cost against the expected...
This work presents a framework for efficiently managing the energy needs of a set of houses connected in a micro-grid configuration. The micro-grid consists of houses and local renewable plants, each seen as independent agents with their specific goals. In particular houses have the option to buy energy from the national grid or from the local renewable plants. We discuss a practical heuristic that...
A new compound-excited doubly salient brushless dc (DSBLDC) generator with power tracking rectification is proposed, which is constituted by a doubly salient electromagnetic machine (DSEM) with split field windings and a simple switched-mode rectifier. The configuration and operation principle are introduced. The inductance features of the generator are analyzed for the utilization of series field...
In this paper, system level design of an oscillating wave energy conversion system (WECS) using doubly-fed induction generator (DFIG) is compared with systems using squirrel-cage induction generator (SCIG) and permanent magnet synchronous generator (PMSG). The comparative study is carried out considering major hardware components and their rating requirements for each system. Although, SCIG and PMSG...
Large turbine generator units connected to series-compensated system may cause the sub-synchronous resonance (SSR) problem. It would result in the damages to the turbinegenerator shaft. To solve the problem, the controllable sub- and super-synchronous current is injected into generator stators. So the 10 kV, 10MVA cascade low-frequency high-power multilevel converter is designed to output the sub-...
A mixed-integer nonlinear programming model is proposed in this paper for reducing excessive standing phase angle difference (SPA) across open circuit breakers in transmission loop paralleling operation. The model adopts both the active power generation increment and the load switch as control variables and takes the relative importance of the loads to be restored into account, resulting in fewer...
Low power devices promote the development of micro power generators (MPGs). There is an increasing interest in harvesting ambient vibration energy through piezoelectric means by which one can potentially draw 10–100's of μW of available power. The limitations of existing piezoelectric harvesters is in their interface circuitry consuming large power and also large amount of charge getting wasted in...
A wide spectrum of problems in the analysis, design and optimization of multi-input/multi-output power generation systems are considered in this paper. We synthesize, implement and validate proportional-integral and softs-witching sliding mode control laws. Testing, characterization and evaluation of renewable power generation systems substantiate our basic, applied and engineering solutions.
A quick synchronization parallel control strategy for multi-paralleled generators based on linear regressive forecasting algorithm is presented in this paper. The proposed controller consists of a speed regulator of diesel engine and an Air Circuit Breaker (ACB) of synchronous generator. The task of the speed regulator is to automatically adjust frequency and load; ACB is used to control the generator...
Switched Reluctance Motors (SRMs) show great advantages of structural simplicity and high reliability in aerial starter/generator applications. This paper introduces the implementation of a high speed switched reluctance starter/generator system. First, the paper proposes a modeling method for switched reluctance starter/generator system, including switched reluctance machine and power circuit. The...
Laws and regulations in Croatia stimulate eligible producers by means of an incentive tariff system for electric energy generation from renewable energy sources and cogenerations (RES) only if the energy is delivered to the network. That causes many problems in case of an “eligible producer who is also a consumer”. The purpose of the article is to initiate an improvement of existing approach to eligible...
This paper presents a novel integrated simulation model of switched reluctance startor/generator system based on wavelet neural network. The switched reluctance startor/generator system is hard to obtain good simulation model due to its critical nonlinearity. Relatively accurate mathematical model would be built by the wavelet neural network due to its powerful learning, approximation and prediction...
This contribution presents the concept of high-power pulse generation from a lower-power generator using the “pulse compression” technique. The principle of operation is based on a transmission line resonator which is “charged-up” by a CW-generator while a switch at the open-end of the resonator is used to trigger the release of the stored energy into a load. The resulting pulse has the duration of...
The utilization of very small hydro power plants has been gaining more and more interest lately. In this context the activation and utilization of the potential energy that is inherent in the drinking water stored in highlevel tanks of waterworks is of growing interest. In the paper at hand, considerations about the modification of a small potable water pipeline for electric power generation are presented...
This work is concentrated on assessment of contribution of distributed generation, represented by small hydro power plants (SHP), in power quality disturbances at low and medium voltage in distribution networks. Investigations are based on the dispersed synchronized measurements at low voltage level including two small hydro power plants and utilization substation, connected to the same medium voltage...
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