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We consider the problem of allocating the cost of a transmission system among load and generator entities. It is a known instance of the classical cooperative game theoretic problem. To solve this problem is a formidable task, as we are dealing with a combinatorial game with transferable utilities. This is an NP hard problem. Therefore, it suffers from the curse of dimensionality. Marginal pricing is a pragmatic alternative to solve this problem since both Kirchhoff current law and voltage law are strictly adhered to. However, the generic complexity of cooperative game theoretic problems cannot be just wished away. It now manifests as the difficulty in choosing an economic slack bus, which may even be dispersed. We propose the application of min-max fairness policy to solve this problem and give an algorithm which will run in polynomial time. During network cost allocation, min-max fairness policy minimizes the maximum regret among participating entities at each step. Maximum regret is measured in terms of price, and lexicographic application of this principle leads to a fair and unique equilibrium price vector. Results on a large network demonstrate fairness as well as tractability of the proposed approach. [ABSTRACT FROM PUBLISHER]

Instrument transformers (ITs) once installed in the field are seldom calibrated. We propose two tests to detect systematic errors in capacitive voltage transformers (CVTs) and current transformers (CTs). The first test, a direct test, compares the mid-point voltage estimated from both ends of a transmission line using PMU data. The second test, an indirect test, analyzes the deviation of the estimated positive sequence line parameter values from the design values. Subsequently, we propose a robust method to simultaneously determine the positive sequence line parameters and IT calibration factors. Special care is given to numerical sensitivity of the method to the noise in the data and we show by Monte Carlo simulations that the proposed approach is accurate and robust. A noteworthy feature of this paper are the case studies based on field PMU data for short, medium, and long length lines of 400 kV and 765 kV. It clearly demonstrates the stability of both line parameters and IT calibration factors and hence justifies the claims. [ABSTRACT FROM AUTHOR]