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\begin{document}
\title{gffjttymtdymt}
\author{Kp~Yadav,
Pv~Dai}
\maketitle
\begin{abstract}
Small signal stability analysis of the power system is mandatory because slowly growing oscillations may end with the blackout of the system.
\end{abstract}
\begin{IEEEkeywords}
Static Var Compensator, CPSS-Conventional Power System Stabilizer, POD- Power Oscillation Damping, Residue Factor, Participation Factor.
\end{IEEEkeywords}
\IEEEpeerreviewmaketitle
\section{INTRODUCTION}
The modern power system is highly interconnected to meet increasing energy demand and to utilize available sources adequately. The interconnection of the power system is necessary for reliable and flexible operation, so the power system needs to be stable against small or large disturbances such as faults, disconnection of large loads or generators, etc. The stability of the system is strongly influenced by the dynamic behavior of components of the system like generators, loads and other control equipment (FACTs devices).
The disturbances in the system cause change in the electrical torque of the synchronous machine [1]. The change in electrical torque due to disturbances can be divided into two parts and is described by :
\begin{equation}\label{1}
\Delta {T_e} = \Delta {T_{es}}\Delta \delta + \Delta {T_{eD}}\Delta \omega
\end{equation}
The analysis of power system oscillations is of interest in a system where the number of generators are working in parallel for supplying power to a common load. In this type of condition, generators produce torques. These torques act to keep the generators in synchronism (synchronizing torque).
\section{MATHEMATICAL MODELING OF SYSTEM} \label{modelingofstudysystem}
In this section each component of multimachine test system is model in the mathematical form as follows:
\subsection{Synchronous Machine}
The synchronous machine is modeled in the form of equations includes swing equation, rotor and stator voltage equations as follows:
\begin{equation}\label{eq2}
\frac{{d\delta }}{{dt}} = {\omega _B}({s_m} - {s_{mo}})
\end{equation}
\begin{equation}\label{eq3}
\frac{{d{s_m}}}{{dt}} = \frac{1}{{2H}}[ - D({s_m} - {s_{mo}}) + {T_m} - {T_e}]
\end{equation}
\begin{equation}\label{eq4}
\frac{{d{E^'}_q}}{{dt}} = \frac{1}{{{T^'}_{do}}}[ - {E^'}_q + ({x_d} - x{'_d}) + {E_{fd}}]
\end{equation}
\begin{equation}\label{eq5}
\frac{{d{E^'}_d}}{{dt}} = \frac{1}{{{T^'}_{qo}}}[ - {E^'}_d - ({x_q} - x{'_q}){i_q}]
\end{equation}
\begin{equation}\label{eq6}
{T_e} = {E^'}_q{i_q} + {E^'}_d{i_d} + (x{'_d} - x{'_q}){i_d}{i_q}
\end{equation}
\section{Conclusion} \label{conclusion}
Power system oscillations can lead the system towards the shutdown. Hence, to damp out these
\end{document}
Responder1
Você tem muitos erros em suas (últimas três) equações
- em vez de
${E^'}_{d}$está correto$E'_{d}$ou$E'_d$ - você tem muitas chaves em suas equações, conseqüentemente é fácil se perder nelas ...
MWE completo (real):
\documentclass[journal]{IEEEtran}
\usepackage{cite}
\usepackage{amsmath,amssymb}
\begin{document}
\begin{equation}\label{1}
\Delta {T_e} = \Delta {T_{es}}\Delta \delta + \Delta {T_{eD}}\Delta \omega
\end{equation}
\begin{equation}\label{eq2}
\frac{{d\delta }}{{dt}} = {\omega _B}({s_m} - {s_{mo}})
\end{equation}
\begin{equation}\label{eq3}
\frac{{d{s_m}}}{{dt}} = \frac{1}{{2H}}[ - D({s_m} - {s_{mo}}) + {T_m} - {T_e}]
\end{equation}
\begin{equation}\label{eq4}
\frac{d E'_q}{dt} = \frac{1}{T'_{do}}[ - E'_q + (x_d - x'_d) + E_{fd}]
\end{equation}
\begin{equation}\label{eq5}
\frac{dE'_d}{dt} = \frac{1}{T'_{qo}}[ - E'_d - (x_q - x'_q) i_q]
\end{equation}
\begin{equation}\label{eq6}
T_e = E'_q i_q + E'_d i_d + (x'_d - x'_q) i_d i_q
\end{equation}
\end{document}
Editar: De acordo com o comentário @egreg, suas equações podem ser escritas como:
\documentclass[journal]{IEEEtran}
\usepackage{cite}
\usepackage{amsmath,amssymb}
\begin{document}
\begin{gather} % <---
\Delta {T_e} = \Delta {T_{es}}\Delta \delta + \Delta {T_{eD}}\Delta \omega
\label{1} \\
\frac{{d\delta }}{{dt}} = {\omega _B}({s_m} - {s_{mo}})
\label{eq2} \\
\frac{{d{s_m}}}{{dt}} = \frac{1}{{2H}}[ - D({s_m} - {s_{mo}}) + {T_m} - {T_e}]
\label{eq3} \\
\frac{d E'_q}{dt} = \frac{1}{T'_{do}}[ - E'_q + (x_d - x'_d) + E_{fd}]
\label{eq4} \\
\frac{dE'_d}{dt} = \frac{1}{T'_{qo}}[ - E'_d - (x_q - x'_q) i_q]
\label{eq5}
\intertext{and finally:}
T_e = E'_q i_q + E'_d i_d + (x'_d - x'_q) i_d i_q
\label{eq6}
\end{gather}
\end{document}
