The implementation of both point collapse (PoC) methods and continuation for the computation voltage points (saddle-node bifurcations) in large AC/DC power systems is described. performance these compared real up to 2158 buses. Computational details PoC are detailed, unique problems encountered due presence high-voltage direct-current (HVDC) transmission, area interchange control, regulating transformers, reactive limits discussed. characteristics a robust flow program presented, its...

Power system loading margin is a fundamental measure of system's proximity to voltage collapse. Linear and quadratic estimates the variation with respect any power parameter or control are derived. Tests 118-bus indicate that accurately predict quantitative effect on altering loading, reactive support, wheeling, load model parameters, line susceptance generator dispatch. The accuracy over useful range ease obtaining linear estimate suggest this method will be practical value in avoiding

Demand relief from customers can help a utility (or any "load serving entity") solve variety of problems. There exist all sorts different demand management programs that utilities use. A critical issue is the incentive paid to customer participate in and provide load relief. The has design cost effective yet attractive contracts. main goal get when needed, do so way. Customers sign up for benefits they derive form front payments, discounts interruption payments exceed their interruption. In...

Voltage collapse and blackout can occur in an electric power system when load powers vary so that the loses stability a saddle node bifurcation. This paper computes at which bifurcation occurs are locally closest to given operating powers. The distance parameter space this is index of voltage minimum margin. computations illustrated for several systems. Monte-Carlo optimization techniques applied obtain multiple margins. use margin sensitivities select controls discussed.< <ETX...

The availability of parallel processing hardware and software presents an opportunity a challenge to apply this new computation technology solve power system problems. allure is that has the potential be cost effectively used on computationally intense objective paper define state art identify what authors see most fertile grounds for future research in as applied computation. As always, such projections are risky fast changing field, but hope will useful researchers practitioners growing area.

In times of stress customers can help a utility by means voluntary demand management programs if they are offered the right incentives. The incentives be optimized estimate outage or substitution costs its customers. This paper illustrates how existing data used to predict customer behavior. More specifically, it shows estimated cost functions calibrated in designing efficient contracts.

The change in the loading margin to voltage collapse when line outages occur is estimated.First a nose curve computed by continuation obtain nominal margin.Then linear and quadratic sensitivities of each contingency are used estimate resulting margin.The method tested on critical area 1390 bus system all IEEE 118 system.The results show effective ranking contingencies very fast computation estimates.

The location of SVC (static VAr compensators) and other types shunt compensation devices for voltage support is an important practical question. This paper considers a tool based on the determination critical modes. Critical modes are computed by studying system in vicinity point collapse. System participation factors mode used to determine most suitable sites reinforcement. Because method does not rely base case linearizations, able properly consider all limits nonlinear effects. tests...

This paper introduces a decentralized control scheme for the parallel connection of multiple rectifiers feeding DC network with numerous inverters. The coordination HVDC power systems without explicit communication is accomplished by use DC-side voltages as "droop" mechanism. side voltage serves role frequency in an ordinary AC system. approach most suitable to superconducting and that span small distances where relatively uniform throughout presents concept context high capacity 10 kV urban...

In times of stress customers can help a utility by means voluntary demand management programs if they are offered the right incentives. The incentives be optimized estimate outage or substitution costs its customers. This paper illustrates how existing data used to predict customer behavior. More specifically, it shows estimated cost functions calibrated in designing efficient contracts.

The use of market mechanisms to determine generation dispatch, and the natural tendency seek improved economic efficiency through rapid updates, raises a critical issue. As frequency market-based dispatch updates increases, there will inevitably be interaction between dynamics markets determining generator commands, physical response generators network interconnections. This paper examines questions stability in such coupled systems by means numeric tests using various update models,...

This paper studies congestion management based on pricing as may be performed by an independent system operator. Four main concepts are discussed: can lead to the same solution optimal power flow; need not have cost information available; good estimates of nonlinear coefficients necessary; and for is separable from purpose transmission network revenue reconciliation. Emphasis determination sufficient observation behavior market permit optimum without explicit communication among parties,...

The numerical method presented in this paper permits the solution of differential equations by trapezoidal integration a time order log2 T, where T is number discrete steps required for solution. parallel processors T/2. Linear and nonlinear examples are presented. example corresponds to small stability problem. classical algorithm compared new terms requirements. Also, comparison includes iterations convergence characteristics. Overall conclusions indicate that always much faster sometimes...

The industrial lignin used here is a byproduct from Kraft pulp mills, extracted black liquor. Since inexpensive, abundant and renewable, its utilization has attracted more attention. In this work, was for the first time as binder material LiFePO4 positive graphite negative electrodes in Li-ion batteries. A procedure pretreatment of lignin, where low-molecular fractions were removed by leaching, necessary to obtain good battery performance. analyzed molecular mass distribution thermal...

Market equilibrium conditions can be derived from more general dynamic equations describing the marketplace. Dynamic provide insights into behavior and stability of markets which are not available static models. For example, with a single supplier declining linear costs (economies scale) may or stable, depending on specific cost characteristics. Markets than one always unstable. This paper illustrates situation where removal congestion makes market

Bulk power transfers in electric systems are limited by transmission network security. Transfer capability measures the maximum transfer permissible under certain assumptions. Once a has been computed for one set of assumptions, it is useful to quickly estimate effect on modifying those This paper presents computationally efficient formula first order sensitivity with respect variation any parameters. The very fast evaluate. approach consistent current industrial practice using dc load flow...

Bulk power transfers in electric systems are limited by transmission network security. Transfer capability measures the maximum transfer permissible under certain assumptions. Once a has been computed for one set of assumptions, it is useful to quickly estimate effect on modifying those This paper presents computationally efficient formula first order sensitivity with respect variation any parameters. The very fast evaluate. approach consistent current industrial practice using DC load flow...

Transformer models for system studies derived without taking into account the frequency dependency of its magnetizing branch are not adequate representing transformer performance over a wide range frequencies and operating conditions. This paper describes procedure dependent characteristics based on an analysis electromagnetic field distribution within laminations core. A one dimension linear diffusion problem is analyzed. simple equivalent circuit Norton type synthetized. exact...

This paper discusses the merits of an analytical method for determining location and amount series compensation to increase steady state power transfer capability in system based primarily on cascading line overload considerations. Steady transmission limits define boundaries a operating point. presents tools identify these analytically estimates change boundary due application shunt compensation. The approach identifies critical lines that can initiate outages optimal methodology also be...

This paper addresses the application of interior point methods to Weighted Least Absolute Value state estimation problem. Interior are applied primal and dual formulations The formulation involves solving least squares problems identical in structure those used conventional Squares estimation. also provides an initial feasible without any extra effort. Computational issues that critical success addressed test results on standard power systems provided.< <ETX...

The classic Ax=b problem in the partitioning of sparse vector matrices is solved by constructing factored components inverses L and U, triangular factors matrix A. number additional fill-ins partitioned U can be made zero. partitions related to path length methods. Allowing some fill-in results fewer partitions. Ordering algorithms most suitable for sparsity preservation require addition themselves. Tests on practical power system with from 118 1993 nodes indicate that proposed approach...

A variation of trapezoidal integration (called with damping) for the solution dynamic equations is described and tested. This method has several advantages over ordinary simulation transients in power systems. The compared to integration, backward Euler Gear 2nd order. comparison based upon local truncation error performance each as a differentiator. tested using transmission line model response voltage step function, HYDC converter its controllers. Trapezoidal damping free from numerical...

The penalty factors calculated by the classical B-coefficients method are shown to be proportional (but not equal) directly from transposed acobian. It is also that economic operating point independent of load and generation distribution Z. Expected computational times in examples with up 5873 buses 943 generators given. evidence presented supports conclusions reached others indicating Jacobian approach superior based on its speed.