Control and Validation of a Reinforced Power Conversion System for Upcoming Bioelectrochemical Power to Gas Stations

This paper presents a proposal for potential bioelectrochemical power to gas stations. It consists of a two-level voltage source converter interfacing the electrical grid on the AC side and an electromethanogenesis based bioelectrochemical system (EMG-BES) working as a stacked module on the DC side. The proposed system converts CO2 and electrical energy into methane, using wastewater as the additional chemical energy input. This energy storage system can contribute to dampening the variability of renewables in the electrical network, provide even flexibility and grid services by controlling the active and reactive power exchanged and is an interesting alternative technology in the market of energy storage for big energy applications. The big challenge for controlling this system lays in the fact that the DC bus voltage of the converter has to be changed in order to regulate the exchanged active power with the grid. This paper presents a cascade approach to control such a system by means of combining external control loops with fast inner loops. The outer power loop, with a proportional-integral (PI) controller with special limitation values and anti-windup capability, is used to generate DC bus voltage reference. An intermediate loop is used for DC bus voltage regulation and current reference generation. A new proportional resonant controller is used to track the current reference. The proposed scheme has been validated through real-time simulation in OPAL OP4510.

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Improved Dynamic Voltage Regulation in a Droop Controlled DC Nanogrid Employing Independently Controlled Battery and Supercapacitor Units

Applied Sciences ◽

10.3390/app8091525 ◽

2018 ◽

Vol 8 (9) ◽

pp. 1525

Author(s):

Ahmad M. A. Malkawi ◽

Luiz A. C. Lopes

Keyword(s):

Energy Storage ◽

Storage System ◽

Voltage Regulation ◽

Potential Contribution ◽

Pass Filter ◽

Power Sources ◽

Dynamic Voltage ◽

Dc Bus ◽

Bus Voltage ◽

The Impact

DC bus voltage signaling (DBS) and droop control are frequently employed in DC nano and microgrids with distributed energy resources (DERs) operating in a decentralized way. This approach is effective in enforcing the desired contributions of power sources and energy storage systems (ESSs) in steady-state conditions. The use of supercapacitors (SCs) along with batteries in a hybrid energy storage system (HESS) can mitigate the impact of high and fast current variations on the losses and lifetime of the battery units. However, by controlling the HESS as a single unit, one forfeits the potential contribution of the SC and its high power capabilities to dynamically improve voltage regulation in a DC nanogrid. This paper discusses an approach where the SC interface is controlled independently from the battery interface, with a small droop factor and a high pass filter (HPF), to produce high and short current pulses and smooth DC bus voltage variations due to sudden power imbalances in the DC nanogrid. Experimental results are presented to show that, unlike in a conventional HESS, the SC unit can be used to improve the dynamic voltage regulation of the DC nanogrid and, indirectly, mitigate the high and fast current variations in the battery.

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An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

The Scientific World JOURNAL ◽

10.1155/2014/271087 ◽

2014 ◽

Vol 2014 ◽

pp. 1-16 ◽

Cited By ~ 7

Author(s):

Muhamad Zalani Daud ◽

Azah Mohamed ◽

M. A. Hannan

Keyword(s):

Energy Storage ◽

Optimization Technique ◽

Current Mode ◽

Voltage Regulation ◽

Boost Converter ◽

Pv System ◽

Battery Energy Storage ◽

Dc Bus ◽

Bus Voltage ◽

Battery Energy

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

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Modelling and Control Design for Energy Management of Grid Connected Hybrid PV-wind System

International Journal of Applied Power Engineering (IJAPE) ◽

10.11591/ijape.v7.i2.pp166-180 ◽

2018 ◽

Vol 7 (2) ◽

pp. 166

Author(s):

Hassan Abouobaida ◽

Said El Bied

Keyword(s):

Internal Control ◽

Reactive Power ◽

Power Conversion ◽

Maximum Power ◽

External Control ◽

Voltage Reference ◽

Control Loop ◽

Control Approach ◽

Dc Bus ◽

Bus Voltage

<p class="MsoNormal" style="margin-right: -14.15pt; text-align: justify; text-justify: inter-ideograph;">This paper deals with the control of hybrid PV-WIND power conversion structure. This paper develops a very important contribution which is the use of a single DC to DC converter, linearization of control of the three- level boost converter (TLBC) considering the imperfections of the passive components. The (TLBC) control provides balancing of capacitor voltages and maximum power operation of PV generator. For reasons of simplicity, a linearization based on the dynamic compensation of the disturbance is proposed. A sensorless maximum power point tracking (MPPT) algorithm is used to maximize a power extracted of the wind generator. The proportional relation between the rotational speed and the output voltage of the rectifier allows to use a voltage sensor to estimate the DC bus voltage reference instead of a mechanical speed sensor. The control of the three-phase inverter allows a transfer of the active power, the power factor close to the unit and thus a limitation of the reactive power injected into the grid. The external control loop performs the regulation of the common DC bus voltage while the internal control loop regulates the dq components of the currents injected into the grid. The simulation results showed the validity of the control approach. The proposed power conversion structure based on a single static converter has shown very good performance in terms of efficiency, the quality of the energy produced, complementarity between the two renewable sources and reliability. The paper ends with conclusions.</p>

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DC Bus Voltage Regulation Strategy for Modular Super Capacitor Energy Storage Based on Extended State Observer

2018 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific) ◽

10.1109/itec-ap.2018.8433264 ◽

2018 ◽

Author(s):

Bi Kaitao ◽

Yang Chuan ◽

Duan Jiandong ◽

Sun Li ◽

An Quntao

Keyword(s):

Energy Storage ◽

Voltage Regulation ◽

State Observer ◽

Extended State Observer ◽

Extended State ◽

Super Capacitor ◽

Dc Bus ◽

Bus Voltage

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Using Energy Storage Inverters of Prosumer Installations for Voltage Control in Low-Voltage Distribution Networks

Energies ◽

10.3390/en14041121 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1121

Author(s):

Rozmysław Mieński ◽

Przemysław Urbanek ◽

Irena Wasiak

Keyword(s):

Energy Storage ◽

Control Strategy ◽

Reactive Power ◽

Low Voltage ◽

Storage System ◽

Distribution Networks ◽

Energy Storage System ◽

Voltage Regulation ◽

Active Power ◽

Total Power

The paper includes the analysis of the operation of low-voltage prosumer installation consisting of receivers and electricity sources and equipped with a 3-phase energy storage system. The aim of the storage application is the management of active power within the installation to decrease the total power exchanged with the supplying network and thus reduce energy costs borne by the prosumer. A solution for the effective implementation of the storage system is presented. Apart from the active power management performed according to the prosumer’s needs, the storage inverter provides the ancillary service of voltage regulation in the network according to the requirements of the network operator. A control strategy involving algorithms for voltage regulation without prejudice to the prosumer’s interest is described in the paper. Reactive power is used first as a control signal and if the required voltage effect cannot be reached, then the active power in the controlled phase is additionally changed and the Energy Storage System (ESS) loading is redistributed in phases in such a way that the total active power set by the prosumer program remains unchanged. The efficiency of the control strategy was tested by means of a simulation model in the PSCAD/EMTDC program. The results of the simulations are presented.

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