https://onlinelibrary.wiley.com/doi/pdf/10.1002/2050-7038.12885

A brief review on microgrids: Operation, applications, modeling, and control

https://www.econstor.eu/bitstream/10419/244125/1/1699081549.pdf

Stochastic management of hybrid AC/DC microgrids considering electric vehicles charging demands

This paper proposes an online steady-state voltage stability assessment scheme to evaluate the proximity to voltage collapse at each bus of a load area. Using a non-iterative holomorphic embedding method (HEM) with a proposed physical germ solution, an accurate loading limit at each load bus can be calculated based on online state estimation on the entire load area and a measurement-based equivalent for the external system. The HEM employs a power series to calculate an accurate Power-Voltage (P-V) curve at each load bus and accordingly evaluates the voltage stability margin considering load variations in the next period. An adaptive two-stage Pade approximants method is proposed to improve the convergence of the power series for accurate determination of the nose point on the P-V curve with moderate computational burden. The proposed method is illustrated in detail on a 4-bus test system and then demonstrated on a load area of the Northeast Power Coordinating Council (NPCC) 48-geneartor, 140-bus power system.

Online Voltage Stability Assessment for Load Areas Based on the Holomorphic Embedding Method

The recently proposed non-iterative load flow method, called the holomorphic embedding method, may encounter the precision issue, i.e. the nontrivial round-off errors caused by the limited digits used in computing the power-voltage (P-V) curve for a heavily loaded power system. This letter proposes a multi-stage scheme to solve such a precision issue and calculate an accurate P-V curve. The scheme is verified on the New England 39-bus power system and benchmarked with the result from the traditional continuation power flow method.

Multi-Stage Holomorphic Embedding Method for Calculating the Power-Voltage Curve

It is very important to drive loads and control the electrical devices with changing electrical energy levels and change a voltage form. While DC-DC converters are used to change the value level of...

A new multi-level inverter with reverse connected dual dc to dc converter at simulation

A modified holomorphic embedding method based hybrid AC-DC microgrid load flow

Load flow studies is a steady state analysis of a power system network at its planning stage where mostly iterative numerical methods are used to solve the load flow equations. But with the rise in complexity of the power networks the convergence time of these algorithms has been increased quite high. To resolve this problem a recursive load flow method has been developed called Holomorphic Embedding method which not only reduces the time complexitybut also increase the probability of existence of the load flow solution. We propose a new load flow problem formulation using the impedance matrix of the power distribution network as the admittance matrix of the system will generally be sparse in nature. Next, by using Pad$\tilde{e}$ approximant we solve this holomorphic embedding load flow functions. Comparative study with well-known load flow methods over IEEE test cases shows the efficiency and applicability of this method over the active distribution networks.

A Modified Holomorphic Embedding Load Flow Method for Active Power Distribution Networks

0This paper will approach a new method for analysis the reduction of higher order continuous time domain systems is adopted. The technical steps of the proposed method are discussed. This method is worn via hybrid function technique towards order reduction of a transfer function model system. The anticipated method also approaches stability of low order models for the considered original stable system of higher order. This technique is very computationally easy in realization and also checking response and stability through this technique.

Analysis Of Higher Order System Using Hybrid Functions Model Order Reduction Techniques

This paper proposes and examines a sinusoidal pulse width modulation (SPWM)-based single-phase diode clamped multilevel inverter for generation of multilevel output voltage. The SPWM signals and digital square pulses are generated using a single PWM module and I/O port of a PIC microcontroller. The performance of the proposed method is checked through simulation after the design of a diode clamp multilevel inverter for 3-level, 5-level, and 9-level output voltage. The 5-level and 3-level output have also been produced by hardware implementation of the designed circuit. Total harmonic distortion (THD) for 3-level, 5-level, and 9-level output voltage waveforms are analyzed.

Design of a Multilevel Inverter Using SPWM Technique

Holomorphic Embedding Load Flow study is a steady state analytical tool used over power network at its planning or implementation stage where recursive method is used to solve the equations. Due to amalgamation of distributed generators within the network the system complexity rises up, whereas, convergence time of the iterative power flow algorithms are quite high and also they does not guaranteed the convergence of load flow method. Therefore, a recursive power flow technique has been proposed namely Holomorphic Embedding method where reduction in time complexity and increase in solution existence probability is there. We proposed a new modeling technique for DSTATCOM devices for holomorphic embedding load flow problem. As this kind of FACTS device will help to regulate the voltage sag and also compensate the reactive power loss. Comparative analysis with existing load flow techniques over numerous test scenarios and a practical grid from Indian distribution system proves the proficiency and applicability of this proposed technique over the active power networks.

Amitava Biswas

Papers

A modified holomorphic embedding method based hybrid AC-DC microgrid load flow

A Modified Holomorphic Embedding Load Flow Method for Active Power Distribution Networks

Analysis Of Higher Order System Using Hybrid Functions Model Order Reduction Techniques

Design of a Multilevel Inverter Using SPWM Technique

Holomorphic Embedding Load Flow Modeling of DSTATCOM for Active Distribution Networks