O alto custo na montagem de laboratórios para o ensino superior é um desafio quando existe contin... more O alto custo na montagem de laboratórios para o ensino superior é um desafio quando existe contingenciamento de recursos. Uma alternativa para contornar o alto custo no desenvolvimento das estruturas básicas dos laboratórios de ensino, consiste no projeto e implementação das bancadas do laboratório, construídas com o auxílio de professores, técnicos e alunos da universidade. Nesse trabalho será abordado o projeto de bancadas didáticas para o laboratório de instalações elétricas, capazes de atender as mais variadas ementas, tanto de cursos como Engenharia Elétrica, Engenharia Civil, Arquitetura e Urbanismo, entre outros. Analisando pelo ponto de vista financeiro, percebe-se uma economia superior a 90%, em comparação à bancadas didáticas comerciais existentes no mercado. Além disso, se for levado em conta o aspecto de ensino aprendizagem dos alunos, os benefícios são maiores, visto que a própria concepção, projeto e construção das bancadas representam uma importante forma de aprendizado prático. Além do mais, a bancada visa aumentar o grau de complexidade das tarefas se comparada aos equipamentos existentes no mercado, visto que engloba mais conceitos. Para aquisição dos materiais, sugerese o uso de recursos institucionais próprios ou parceria com empresas públicas e privadas.
Master Dissertation Pos-Graduation Program on Electrical Engineering Federal University of Santa ... more Master Dissertation Pos-Graduation Program on Electrical Engineering Federal University of Santa Maria STUDY, MODELING AND CONTROL OF MICRO HYDROELECTRIC POWER GENERATION STATION WITH INDUCTION GENERATOR Author: Lucas Giuliani Scherer Research Supervisor: Robinson Figueiredo de Camargo , Dr. Santa Maria, January 30, 2012. In the last decade there has been a significant inc rease in interest in microgeneration technologies for electric power. Sources of hydraul ic power generation, wind and solar technologies represent some of the important develo pments that have had arising from the research efforts aimed at this area of power genera tion. The reason for this interest is due to the consolid ation of what is called future in terms of power generation, which is based on decentraliza tion of power generation through interconnected centers of small generators / consum ers. At distribution level, distributed generation sourc es, together with the loads connected to its bus, forms what is defined as a microgrid. D epending on the instantaneous load and installed generation capacity, a microgrid can beha v as a point of consumption or generation of energy at different times, being able to operate also connected to the network or islanded form according to the quality energy supplied or ne ed in case of system failure. Among the technologies of microgeneration, micro hy dro power plants with selfexcited induction generators (SEIG) came to represe nt an excellent option for electricity generation in isolated areas, mainly due to its cha racteristics of robustness and low cost, compared to synchronous machines. It is an alternat ive to the use of synchronous generators in low-power systems powered by small hydroelectric plants, rich in our country. In this sense, this Master's thesis deals with the modeling and control of a micro hydro power plant with SEIG with frequency and voltage co ntr l. The frequency control is achieved by controlling the opening of the feeding system of the turbine while the voltage control is performed through the control of reactive power of the set, using for this a Pulse Width Modulated (PWM) inverter. 10 Based on these definitions and knowledge acquired, t was proposed a system to be implemented experimentally, consisting of a micro h ydro power plant, in this case a motor driven by a voltage PWM inverter, emulating the beh avior of a turbine coupled to the induction generator. The terminals of the SEIG feed a bus where loads with different characteristics are connected, featuring a microgri d, having as main goal the control of the voltage and frequency stability of the energy suppl ied by the generator to the isolated system. Among the studies developed for the implementation of the prototype is possible to highlight: three-phase system modeling, hydraulic s ystem modeling, voltage and frequency control, and synchronization method. Throughout this paper, simulations and experimental results are presented in order to be demonstrated the applicability of control method s, their performance and technical feasibility of the system.
2021 Brazilian Power Electronics Conference (COBEP), Nov 7, 2021
This paper presents the design and simulation of a static excitation system for a 5 kVA Synchrono... more This paper presents the design and simulation of a static excitation system for a 5 kVA Synchronous Generator (SG) using a Two-Switch Forward (TSF) converter. The objective is to evaluate the use of the converter to control the generator field voltage and regulate the system terminal voltages. A standalone generation system is considered, where the converter dc bus is supplied by a battery energy storage system (BESS) or photovoltaic (PV) panels set. The control structure is composed of two loops, the external one controls the terminal voltage and generates the reference for the internal one, which controls the field voltage, responsible for the SG excitation. Simulation results show the suitable performance of the excitation system under output disturbances.
ABSTRACT This paper proposes a simulation and emulation system using Matlab and SCADA (supervisor... more ABSTRACT This paper proposes a simulation and emulation system using Matlab and SCADA (supervisory control and data acquisition). Matlab is used for micro hydropower plant simulation. The emulation system is composed by a SEIG (self-excited induction generator) coupled to an electric motor drived by frequency converter. The Modbus RTU (Remote terminal unit) protocol connects SCADA with the frequency converter and OPC (object linking and embedding for process control) links SCADA with the Matlab environment. Hydropower plants simulation systems requires integration of several components and for this purpose it was used a SCADA system to process information and make it available to the operator in real time.
ABSTRACT This paper deals with the development of a hybrid method of control for voltage regulati... more ABSTRACT This paper deals with the development of a hybrid method of control for voltage regulation in micro hydro power station using self-excited induction generation. The proposed method performs the voltage regulation with the use of capacitor banks plus static VAR compensator. A considerable literature review was undertaken to identify the key control systems for voltage regulation applied to self-excited induction generator. A control algorithm and a project for the variable capacitors are proposed based on the resolution of normative procedures of Electricity Distribution in the National Electric System. Simulation and experimental results are presented to demonstrate the performance of the proposed hybrid method for the voltage regulation of the self-excited induction generator during variations of different types of load. Moreover, experimental results concerning the analysis of reactive power processed by the static VAR compensator during its operation in the hybrid method are obtained. These results are compared with the results obtained through the method that uses only the static VAR compensator, where the hybrid method has advantages in terms of reduction of the size of the static VAR compensator.
(GEPOC)-SM/RS-Brasil Resumo. Este trabalho é a interligação e operação conjunta de fontes gerador... more (GEPOC)-SM/RS-Brasil Resumo. Este trabalho é a interligação e operação conjunta de fontes geradoras de natureza hídrica e fotovoltaica, bem como o emprego de um banco de baterias para armazenamento de energia. A geração hídrica é constituída por uma máquina primária não controlada acoplada a um gerador de indução auto-excitado (GIAE). O controle de amplitude das tensões geradas pelo GIAE é realizado através de um compensador síncrono estático de distribuição (DSTATCOM). Conectado ao barramento CC do DSTATCOM, encontram-se os sistemas de geração fotovoltaica e de armazenamento de energia. O arranjo fotovoltaico considerado no trabalho é conectado ao barramento CC do DSTATCOM através de um conversor elevador, o qual permite além do acoplamento de tensão, o rastreamento do ponto de máxima potência (MPPT) do arranjo. O sistema armazenador, por sua vez, é constituído por um banco de baterias e interligado ao barramento CC através de um conversor CC/CC bidirecional para o controle do fluxo de carga e descarga do mesmo. O objetivo do banco de baterias é manter regulada a frequência das tensões do barramento CA do sistema. Em auxílio ao banco de baterias, utiliza-se uma carga eletrônica controlada (ELC) para dissipação da potência ativa excedente aos limites de carga do sistema de armazenamento. Resultados de simulação são apresentados para validar o trabalho de controle e modelagem desenvolvido, sob variações de carga, temperatura, irradiância e velocidade da máquina primária avaliando a efetividade da regulação de amplitude e frequência no ponto de conexão de cargas. Também são expostos resultados experimentais do conversor bidirecional em modo de descarga para confirmar a funcionalidade do controle de corrente sobre o banco de baterias. Palavras-chave: Sistema híbrido de geração, energia fotovoltaica, banco de baterias 1. INTRODUÇÃO Países desenvolvidos e com grandes densidades populacionais são responsáveis pelos maiores consumos de energia elétrica no mundo. Como exemplo citam-se, os países membros da Organização para a Cooperação e Desenvolvimento Econômico (OCDE) e a China (Scherer, 2016). Segundo (International energy agency, 2016) em
This paper deals with a system control for voltage and frequency regulation in stand-alone genera... more This paper deals with a system control for voltage and frequency regulation in stand-alone generation systems based on self-excited induction generators (SEIG). A three-wire hybrid topology composed by switchable capacitor banks and distribution static compensator (DSTATCOM) is considered. The DSTATCOM is controlled by proportional-resonant-derivative (PRD) controllers in association to proportional-integral (PI) controllers in order to compensate the system reactive power, balance induction generator (IG) currents and compensate harmonic currents. An electronic load controller connected to the three-phase bus guarantee the frequency regulation by the control of active power. Experimental results are presented to demonstrate its performance.
ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in... more ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in micro hydro power station using self-excited induction generation applied in three-phase four-wire systems. The proposed topology is a combination of a three-phase four legs static synchronous compensator (STATCOM) and capacitor banks connected in parallel to the AC voltage bar. It is considered a three wires generator with no accessible neutral point being the neutral terminal for the load created through the neutral terminal of the excitation capacitor and the controller, which provides the choice to connect the loads either star or delta configurations. A control algorithm and a project for the variable capacitors are proposed based on the specifications of the STATCOM. The proposed generating system is modeled and simulated in MATLAB. Simulation results and preliminary experimental results are presented to demonstrate the performance of the proposed new hybrid method for the voltage regulation of the self-excited induction generator as well as to demonstrate the capability of an isolated generating system for feeding three-phase balanced loads.
ABSTRACT This paper proposes a system of control and data acquisition (SCADA) to be applied in a ... more ABSTRACT This paper proposes a system of control and data acquisition (SCADA) to be applied in a distributed generation system. This system was developed with low-cost technology and it is based in wireless communication to perform the exchange of information between generation system and SCADA. The implementation of the proposed system contributes to operation, monitoring and maintenance of systems named smart grids, allowing the management of different generation sources, such as hydro, solar, wind, and others, through conventional monitoring systems like mobile devices, employing Web tools. Experimental results are presented in order to demonstrate the applicability of the system developed.
ABSTRACT This paper presents an approach to full modeling and control of micro hydro power statio... more ABSTRACT This paper presents an approach to full modeling and control of micro hydro power stations using linear model of hydraulic turbine applied on induction generators. Constant frequency control is obtained by a speed governor applied in turbine feed system while constant voltage control is reached through reactive power control by a voltage-source inverter (VSI). In order to reach effective frequency control it is proposed the use of motor flux estimation algorithm to obtain the measurement of instantaneous rotor speed without the necessity of mechanical sensor applied on his shaft, resulting in inherent cost reduction. Simulation results, considering step changes in load and frequency reference setting, have been considered. Experimental results related to reactive power control and voltage regulation are presented and have shown satisfactory dynamic performance.
The interest in technologies related to microgeneration has increased over the last decade. Hydro... more The interest in technologies related to microgeneration has increased over the last decade. Hydro, wind and solar power represent some of the technologies which had significant improvement. Among these technologies, micro hydro power stations with self-excited induction generators (IG) became an excellent choice for limited power generation in isolated areas, due basically to its robustness and low cost, compared to synchronous machine. This paper describes the controllers for micro hydro power stations for island operation based on nonlinear model of hydraulic turbine with a selfexcited induction generators. Frequency control is obtained by a speed governor applied to the turbine feed system while constant voltage control is reached through reactive power control using a voltage source inverter (VSI). In order to reach effective frequency control, it is proposed the use of a motor flux estimation algorithm to obtain the measurement of instantaneous rotor speed without using a mechanical sensor applied on his shaft resulting in inherent cost reduction. Simulation results are given and they illustrate the transient behavior due step changes in load and frequency reference setting point. I.
This study deals with the development of a proportional-resonant (PR) control applied on voltage ... more This study deals with the development of a proportional-resonant (PR) control applied on voltage regulation and harmonics compensation of a standalone self-excited induction generator (SEIG) for micro-hydro power generation system. The generation system considers: (i) a three-phase induction generator (IG) as SEIG, (ii) which is driven by an unregulated microhydro turbine, (iii) a three-phase three-legs distribution static synchronous compensator (DSTATCOM) and (iv) linear and nonlinear loads connected to the AC bus. The voltage regulation is performed through the injection of reactive power to the AC bus through the DSTATCOM, providing excitation current to the IG. It is considered the employment of PR control techniques, which offers suitable voltage regulation through voltage harmonics compensation in the point of common coupling. Furthermore, frequency regulation is performed on the demand side by an electronic load control connected to the DC bus of the DSTATCOM. Experimental results were obtained to demonstrate the good performance of the voltage and frequency regulation, provided by the control system during transients of linear and non-linear loads.
This paper presents the application of the sliding mode (SM) control method applied in the voltag... more This paper presents the application of the sliding mode (SM) control method applied in the voltage regulation of stand-alone self-excited induction generator (SEIG) based systems under nonlinear and unbalanced loads. For this study, it is considered a three-phase three-wire topology, in which the voltage regulation is done by a distribution static compensator (DSTATCOM). It is proposed a SM controller to be applied in the current control of the DSTATCOM. The control is implemented so that in addition to regulate the voltage, the DSTATCOM can also compensate for harmonics and unbalances in the load currents, improving in this way the overall power quality of the system. The proposed control system is simulated in the software Matlab and implemented on an experimental setup. The test results show the implemented SM current control is able to reduce the harmonic and unbalance content of the generator voltages and currents.
ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in... more ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in micro hydro power station using self-excited induction generator applied in three-phase four-wire systems. The proposed topology is a combination of a three-phase four legs static VAR compensator (SVC) and capacitor banks connected in parallel to the AC voltage bar. It is considered a three wires generator with no accessible neutral point being the neutral terminal for the load created through the neutral terminal of the excitation capacitor and the fourth leg of SVC, which provides the choice to connect the loads either star or delta configurations. A control algorithm and a project for the variable capacitors are proposed based on the specifications of the SVC. The proposed generating system is modeled and simulated in MATLAB. Simulation results and preliminary experimental results are presented to demonstrate the performance of the proposed new hybrid method for the voltage regulation of the self-excited induction generator. In the sequence, simulation results are presented in order to demonstrate the capability of the proposed system for feeding three-phase and single-phase balanced and unbalanced loads, with no distortion of the generated voltages.
This study deals with a control system for voltage regulation of stand-alone generation systems b... more This study deals with a control system for voltage regulation of stand-alone generation systems based on self-excited induction generators (SEIG). It is considered a four-wire hybrid topology composed by switchable capacitor banks and distribution static compensator (DSTATCOM). While the switchable capacitor banks supply the most part of the reactive power for voltage regulation, the DSTATCOM is controlled in order to supply the difference of reactive power, to balance IG currents and compensate harmonics of load currents. To accomplish that, it is proposed the use of proportional-resonant-derivative (PRD) controllers in association to proportional-integral (PI) controllers to control the compensation currents processed by DSTATCOM. The proposed method of voltage regulation using DSTATCOM-switchable capacitors is simulated in software Simulink/Matlab® and the results are presented to demonstrate its performance.
This papers proposes a proportional-resonant (PR) stator current controller applied on a self exc... more This papers proposes a proportional-resonant (PR) stator current controller applied on a self excited induction generator (SEIG) based system. It is considered a three-phase, three-wire isolated system, composed by an induction generator (IG) driven by a constant speed prime mover, and regulated by a three-phase three-leg distribution synchronous static compensator (DSTATCOM). The control system is implemented on the DSTATCOM, which directly controls the SEIG stator currents, allowing for harmonic and unbalanced current compensation without the need of measuring the load currents. Experimental results are presented to demonstrate the feasibility of the proposed system.
This paper presents the development and control of a hybrid power micro-generation system. The pr... more This paper presents the development and control of a hybrid power micro-generation system. The projected system is based on hydro and solar photovoltaic (PV) sources. The hydro system is composed by a self-excited induction generator (SEIG) coupled to an uncontrolled primary machine. A battery energy storage system (BESS) and an electronic load controller (ELC) are also applied with purpose of active power balancing. All the DC elements of the system are tied to the DC bus of a distribution static synchronous compensator (DSTATCOM). The DSTATCOM is responsible for the reactive power balancing of the system. Results are presented for demonstration of the model and control developed working under load and irradiance variation and also to evaluate the effectiveness of the voltage and frequency regulation at the load connection point.
This paper deals with the development of a load current sensorless control system applied on a di... more This paper deals with the development of a load current sensorless control system applied on a distribution synchronous static compensator (DSTATCOM) for the voltage regulation and load disturbance compensation of self excited induction generator (SEIG) based systems. It is considered a three-phase, three-wire isolated system, composed by an induction generator (IG) driven by a constant speed prime mover, and regulated by a three-phase three-leg DSTATCOM. The SEIG stator currents are controlled directly by a proportional-resonant (PR) current controller, which imposes sinusoidal currents and rejects disturbances at the grid fundamental frequency. Experimental results are presented to demonstrate the feasibility of the proposed system.
O alto custo na montagem de laboratórios para o ensino superior é um desafio quando existe contin... more O alto custo na montagem de laboratórios para o ensino superior é um desafio quando existe contingenciamento de recursos. Uma alternativa para contornar o alto custo no desenvolvimento das estruturas básicas dos laboratórios de ensino, consiste no projeto e implementação das bancadas do laboratório, construídas com o auxílio de professores, técnicos e alunos da universidade. Nesse trabalho será abordado o projeto de bancadas didáticas para o laboratório de instalações elétricas, capazes de atender as mais variadas ementas, tanto de cursos como Engenharia Elétrica, Engenharia Civil, Arquitetura e Urbanismo, entre outros. Analisando pelo ponto de vista financeiro, percebe-se uma economia superior a 90%, em comparação à bancadas didáticas comerciais existentes no mercado. Além disso, se for levado em conta o aspecto de ensino aprendizagem dos alunos, os benefícios são maiores, visto que a própria concepção, projeto e construção das bancadas representam uma importante forma de aprendizado prático. Além do mais, a bancada visa aumentar o grau de complexidade das tarefas se comparada aos equipamentos existentes no mercado, visto que engloba mais conceitos. Para aquisição dos materiais, sugerese o uso de recursos institucionais próprios ou parceria com empresas públicas e privadas.
Master Dissertation Pos-Graduation Program on Electrical Engineering Federal University of Santa ... more Master Dissertation Pos-Graduation Program on Electrical Engineering Federal University of Santa Maria STUDY, MODELING AND CONTROL OF MICRO HYDROELECTRIC POWER GENERATION STATION WITH INDUCTION GENERATOR Author: Lucas Giuliani Scherer Research Supervisor: Robinson Figueiredo de Camargo , Dr. Santa Maria, January 30, 2012. In the last decade there has been a significant inc rease in interest in microgeneration technologies for electric power. Sources of hydraul ic power generation, wind and solar technologies represent some of the important develo pments that have had arising from the research efforts aimed at this area of power genera tion. The reason for this interest is due to the consolid ation of what is called future in terms of power generation, which is based on decentraliza tion of power generation through interconnected centers of small generators / consum ers. At distribution level, distributed generation sourc es, together with the loads connected to its bus, forms what is defined as a microgrid. D epending on the instantaneous load and installed generation capacity, a microgrid can beha v as a point of consumption or generation of energy at different times, being able to operate also connected to the network or islanded form according to the quality energy supplied or ne ed in case of system failure. Among the technologies of microgeneration, micro hy dro power plants with selfexcited induction generators (SEIG) came to represe nt an excellent option for electricity generation in isolated areas, mainly due to its cha racteristics of robustness and low cost, compared to synchronous machines. It is an alternat ive to the use of synchronous generators in low-power systems powered by small hydroelectric plants, rich in our country. In this sense, this Master's thesis deals with the modeling and control of a micro hydro power plant with SEIG with frequency and voltage co ntr l. The frequency control is achieved by controlling the opening of the feeding system of the turbine while the voltage control is performed through the control of reactive power of the set, using for this a Pulse Width Modulated (PWM) inverter. 10 Based on these definitions and knowledge acquired, t was proposed a system to be implemented experimentally, consisting of a micro h ydro power plant, in this case a motor driven by a voltage PWM inverter, emulating the beh avior of a turbine coupled to the induction generator. The terminals of the SEIG feed a bus where loads with different characteristics are connected, featuring a microgri d, having as main goal the control of the voltage and frequency stability of the energy suppl ied by the generator to the isolated system. Among the studies developed for the implementation of the prototype is possible to highlight: three-phase system modeling, hydraulic s ystem modeling, voltage and frequency control, and synchronization method. Throughout this paper, simulations and experimental results are presented in order to be demonstrated the applicability of control method s, their performance and technical feasibility of the system.
2021 Brazilian Power Electronics Conference (COBEP), Nov 7, 2021
This paper presents the design and simulation of a static excitation system for a 5 kVA Synchrono... more This paper presents the design and simulation of a static excitation system for a 5 kVA Synchronous Generator (SG) using a Two-Switch Forward (TSF) converter. The objective is to evaluate the use of the converter to control the generator field voltage and regulate the system terminal voltages. A standalone generation system is considered, where the converter dc bus is supplied by a battery energy storage system (BESS) or photovoltaic (PV) panels set. The control structure is composed of two loops, the external one controls the terminal voltage and generates the reference for the internal one, which controls the field voltage, responsible for the SG excitation. Simulation results show the suitable performance of the excitation system under output disturbances.
ABSTRACT This paper proposes a simulation and emulation system using Matlab and SCADA (supervisor... more ABSTRACT This paper proposes a simulation and emulation system using Matlab and SCADA (supervisory control and data acquisition). Matlab is used for micro hydropower plant simulation. The emulation system is composed by a SEIG (self-excited induction generator) coupled to an electric motor drived by frequency converter. The Modbus RTU (Remote terminal unit) protocol connects SCADA with the frequency converter and OPC (object linking and embedding for process control) links SCADA with the Matlab environment. Hydropower plants simulation systems requires integration of several components and for this purpose it was used a SCADA system to process information and make it available to the operator in real time.
ABSTRACT This paper deals with the development of a hybrid method of control for voltage regulati... more ABSTRACT This paper deals with the development of a hybrid method of control for voltage regulation in micro hydro power station using self-excited induction generation. The proposed method performs the voltage regulation with the use of capacitor banks plus static VAR compensator. A considerable literature review was undertaken to identify the key control systems for voltage regulation applied to self-excited induction generator. A control algorithm and a project for the variable capacitors are proposed based on the resolution of normative procedures of Electricity Distribution in the National Electric System. Simulation and experimental results are presented to demonstrate the performance of the proposed hybrid method for the voltage regulation of the self-excited induction generator during variations of different types of load. Moreover, experimental results concerning the analysis of reactive power processed by the static VAR compensator during its operation in the hybrid method are obtained. These results are compared with the results obtained through the method that uses only the static VAR compensator, where the hybrid method has advantages in terms of reduction of the size of the static VAR compensator.
(GEPOC)-SM/RS-Brasil Resumo. Este trabalho é a interligação e operação conjunta de fontes gerador... more (GEPOC)-SM/RS-Brasil Resumo. Este trabalho é a interligação e operação conjunta de fontes geradoras de natureza hídrica e fotovoltaica, bem como o emprego de um banco de baterias para armazenamento de energia. A geração hídrica é constituída por uma máquina primária não controlada acoplada a um gerador de indução auto-excitado (GIAE). O controle de amplitude das tensões geradas pelo GIAE é realizado através de um compensador síncrono estático de distribuição (DSTATCOM). Conectado ao barramento CC do DSTATCOM, encontram-se os sistemas de geração fotovoltaica e de armazenamento de energia. O arranjo fotovoltaico considerado no trabalho é conectado ao barramento CC do DSTATCOM através de um conversor elevador, o qual permite além do acoplamento de tensão, o rastreamento do ponto de máxima potência (MPPT) do arranjo. O sistema armazenador, por sua vez, é constituído por um banco de baterias e interligado ao barramento CC através de um conversor CC/CC bidirecional para o controle do fluxo de carga e descarga do mesmo. O objetivo do banco de baterias é manter regulada a frequência das tensões do barramento CA do sistema. Em auxílio ao banco de baterias, utiliza-se uma carga eletrônica controlada (ELC) para dissipação da potência ativa excedente aos limites de carga do sistema de armazenamento. Resultados de simulação são apresentados para validar o trabalho de controle e modelagem desenvolvido, sob variações de carga, temperatura, irradiância e velocidade da máquina primária avaliando a efetividade da regulação de amplitude e frequência no ponto de conexão de cargas. Também são expostos resultados experimentais do conversor bidirecional em modo de descarga para confirmar a funcionalidade do controle de corrente sobre o banco de baterias. Palavras-chave: Sistema híbrido de geração, energia fotovoltaica, banco de baterias 1. INTRODUÇÃO Países desenvolvidos e com grandes densidades populacionais são responsáveis pelos maiores consumos de energia elétrica no mundo. Como exemplo citam-se, os países membros da Organização para a Cooperação e Desenvolvimento Econômico (OCDE) e a China (Scherer, 2016). Segundo (International energy agency, 2016) em
This paper deals with a system control for voltage and frequency regulation in stand-alone genera... more This paper deals with a system control for voltage and frequency regulation in stand-alone generation systems based on self-excited induction generators (SEIG). A three-wire hybrid topology composed by switchable capacitor banks and distribution static compensator (DSTATCOM) is considered. The DSTATCOM is controlled by proportional-resonant-derivative (PRD) controllers in association to proportional-integral (PI) controllers in order to compensate the system reactive power, balance induction generator (IG) currents and compensate harmonic currents. An electronic load controller connected to the three-phase bus guarantee the frequency regulation by the control of active power. Experimental results are presented to demonstrate its performance.
ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in... more ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in micro hydro power station using self-excited induction generation applied in three-phase four-wire systems. The proposed topology is a combination of a three-phase four legs static synchronous compensator (STATCOM) and capacitor banks connected in parallel to the AC voltage bar. It is considered a three wires generator with no accessible neutral point being the neutral terminal for the load created through the neutral terminal of the excitation capacitor and the controller, which provides the choice to connect the loads either star or delta configurations. A control algorithm and a project for the variable capacitors are proposed based on the specifications of the STATCOM. The proposed generating system is modeled and simulated in MATLAB. Simulation results and preliminary experimental results are presented to demonstrate the performance of the proposed new hybrid method for the voltage regulation of the self-excited induction generator as well as to demonstrate the capability of an isolated generating system for feeding three-phase balanced loads.
ABSTRACT This paper proposes a system of control and data acquisition (SCADA) to be applied in a ... more ABSTRACT This paper proposes a system of control and data acquisition (SCADA) to be applied in a distributed generation system. This system was developed with low-cost technology and it is based in wireless communication to perform the exchange of information between generation system and SCADA. The implementation of the proposed system contributes to operation, monitoring and maintenance of systems named smart grids, allowing the management of different generation sources, such as hydro, solar, wind, and others, through conventional monitoring systems like mobile devices, employing Web tools. Experimental results are presented in order to demonstrate the applicability of the system developed.
ABSTRACT This paper presents an approach to full modeling and control of micro hydro power statio... more ABSTRACT This paper presents an approach to full modeling and control of micro hydro power stations using linear model of hydraulic turbine applied on induction generators. Constant frequency control is obtained by a speed governor applied in turbine feed system while constant voltage control is reached through reactive power control by a voltage-source inverter (VSI). In order to reach effective frequency control it is proposed the use of motor flux estimation algorithm to obtain the measurement of instantaneous rotor speed without the necessity of mechanical sensor applied on his shaft, resulting in inherent cost reduction. Simulation results, considering step changes in load and frequency reference setting, have been considered. Experimental results related to reactive power control and voltage regulation are presented and have shown satisfactory dynamic performance.
The interest in technologies related to microgeneration has increased over the last decade. Hydro... more The interest in technologies related to microgeneration has increased over the last decade. Hydro, wind and solar power represent some of the technologies which had significant improvement. Among these technologies, micro hydro power stations with self-excited induction generators (IG) became an excellent choice for limited power generation in isolated areas, due basically to its robustness and low cost, compared to synchronous machine. This paper describes the controllers for micro hydro power stations for island operation based on nonlinear model of hydraulic turbine with a selfexcited induction generators. Frequency control is obtained by a speed governor applied to the turbine feed system while constant voltage control is reached through reactive power control using a voltage source inverter (VSI). In order to reach effective frequency control, it is proposed the use of a motor flux estimation algorithm to obtain the measurement of instantaneous rotor speed without using a mechanical sensor applied on his shaft resulting in inherent cost reduction. Simulation results are given and they illustrate the transient behavior due step changes in load and frequency reference setting point. I.
This study deals with the development of a proportional-resonant (PR) control applied on voltage ... more This study deals with the development of a proportional-resonant (PR) control applied on voltage regulation and harmonics compensation of a standalone self-excited induction generator (SEIG) for micro-hydro power generation system. The generation system considers: (i) a three-phase induction generator (IG) as SEIG, (ii) which is driven by an unregulated microhydro turbine, (iii) a three-phase three-legs distribution static synchronous compensator (DSTATCOM) and (iv) linear and nonlinear loads connected to the AC bus. The voltage regulation is performed through the injection of reactive power to the AC bus through the DSTATCOM, providing excitation current to the IG. It is considered the employment of PR control techniques, which offers suitable voltage regulation through voltage harmonics compensation in the point of common coupling. Furthermore, frequency regulation is performed on the demand side by an electronic load control connected to the DC bus of the DSTATCOM. Experimental results were obtained to demonstrate the good performance of the voltage and frequency regulation, provided by the control system during transients of linear and non-linear loads.
This paper presents the application of the sliding mode (SM) control method applied in the voltag... more This paper presents the application of the sliding mode (SM) control method applied in the voltage regulation of stand-alone self-excited induction generator (SEIG) based systems under nonlinear and unbalanced loads. For this study, it is considered a three-phase three-wire topology, in which the voltage regulation is done by a distribution static compensator (DSTATCOM). It is proposed a SM controller to be applied in the current control of the DSTATCOM. The control is implemented so that in addition to regulate the voltage, the DSTATCOM can also compensate for harmonics and unbalances in the load currents, improving in this way the overall power quality of the system. The proposed control system is simulated in the software Matlab and implemented on an experimental setup. The test results show the implemented SM current control is able to reduce the harmonic and unbalance content of the generator voltages and currents.
ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in... more ABSTRACT This paper deals with the development of a new hybrid topology for voltage regulation in micro hydro power station using self-excited induction generator applied in three-phase four-wire systems. The proposed topology is a combination of a three-phase four legs static VAR compensator (SVC) and capacitor banks connected in parallel to the AC voltage bar. It is considered a three wires generator with no accessible neutral point being the neutral terminal for the load created through the neutral terminal of the excitation capacitor and the fourth leg of SVC, which provides the choice to connect the loads either star or delta configurations. A control algorithm and a project for the variable capacitors are proposed based on the specifications of the SVC. The proposed generating system is modeled and simulated in MATLAB. Simulation results and preliminary experimental results are presented to demonstrate the performance of the proposed new hybrid method for the voltage regulation of the self-excited induction generator. In the sequence, simulation results are presented in order to demonstrate the capability of the proposed system for feeding three-phase and single-phase balanced and unbalanced loads, with no distortion of the generated voltages.
This study deals with a control system for voltage regulation of stand-alone generation systems b... more This study deals with a control system for voltage regulation of stand-alone generation systems based on self-excited induction generators (SEIG). It is considered a four-wire hybrid topology composed by switchable capacitor banks and distribution static compensator (DSTATCOM). While the switchable capacitor banks supply the most part of the reactive power for voltage regulation, the DSTATCOM is controlled in order to supply the difference of reactive power, to balance IG currents and compensate harmonics of load currents. To accomplish that, it is proposed the use of proportional-resonant-derivative (PRD) controllers in association to proportional-integral (PI) controllers to control the compensation currents processed by DSTATCOM. The proposed method of voltage regulation using DSTATCOM-switchable capacitors is simulated in software Simulink/Matlab® and the results are presented to demonstrate its performance.
This papers proposes a proportional-resonant (PR) stator current controller applied on a self exc... more This papers proposes a proportional-resonant (PR) stator current controller applied on a self excited induction generator (SEIG) based system. It is considered a three-phase, three-wire isolated system, composed by an induction generator (IG) driven by a constant speed prime mover, and regulated by a three-phase three-leg distribution synchronous static compensator (DSTATCOM). The control system is implemented on the DSTATCOM, which directly controls the SEIG stator currents, allowing for harmonic and unbalanced current compensation without the need of measuring the load currents. Experimental results are presented to demonstrate the feasibility of the proposed system.
This paper presents the development and control of a hybrid power micro-generation system. The pr... more This paper presents the development and control of a hybrid power micro-generation system. The projected system is based on hydro and solar photovoltaic (PV) sources. The hydro system is composed by a self-excited induction generator (SEIG) coupled to an uncontrolled primary machine. A battery energy storage system (BESS) and an electronic load controller (ELC) are also applied with purpose of active power balancing. All the DC elements of the system are tied to the DC bus of a distribution static synchronous compensator (DSTATCOM). The DSTATCOM is responsible for the reactive power balancing of the system. Results are presented for demonstration of the model and control developed working under load and irradiance variation and also to evaluate the effectiveness of the voltage and frequency regulation at the load connection point.
This paper deals with the development of a load current sensorless control system applied on a di... more This paper deals with the development of a load current sensorless control system applied on a distribution synchronous static compensator (DSTATCOM) for the voltage regulation and load disturbance compensation of self excited induction generator (SEIG) based systems. It is considered a three-phase, three-wire isolated system, composed by an induction generator (IG) driven by a constant speed prime mover, and regulated by a three-phase three-leg DSTATCOM. The SEIG stator currents are controlled directly by a proportional-resonant (PR) current controller, which imposes sinusoidal currents and rejects disturbances at the grid fundamental frequency. Experimental results are presented to demonstrate the feasibility of the proposed system.
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Papers by Lucas Scherer