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Distance relays are the workhorses of transmission-line protection systems. But those close to the electrical center will pickup even during transient instability. To identify them, we introduce a new coordinate system with normalized minimum magnitude of positive-sequence voltage on the line (\mathrmV{\mathrm{min}\mathrm{pu}}) as the y-coordinate and angular separation of positive-sequence voltage phasors at line terminals (\delta \text{SR}) as the x-coordinate. We show that in the \delta \text{SR}-{\mathrm{V}}{\mathrm{min}\mathrm{pu}} plane, the electrical center has a strong separation from a three-phase fault and stable disturbances. Subsequently, we propose a combined out-of-step prediction and relay blocking scheme. It uses line-end phasor measurement unit inputs for detecting vulnerable relays and blocking their zone 1 trip for a limited time interval before ingression into zone 1. We also show that it is possible to detect a line fault during the block state and consequently rescind the block decision. Extension of the proposed scheme to zone 2 and zone 3 is also described. Simulations considering noisy data and round robin delays demonstrate efficacy of the proposal. [ABSTRACT FROM PUBLISHER]

In India, apart from state owned generators, a central sector power pool has been created consisting of central sector power stations. The Central Transmission Utility (CTU) has built an EHV network to transfer this power to the constituents of the regional network. To recover the costs incurred, the CTU levies the Transmission Service Charges (TSC) over the constituents. The constituents are billed for network usage charges which are proportional to their allocated share in the central sector power generation. An ideal pricing mechanism would have been to find out the usage of the network by the constituents and charge accordingly. In this paper, a real power tracing based method for recovery of Transmission Service Charge (TSC) from the constituents of Western regional grid in India is proposed. The method uses proportionality based real power tracing to find out the network usage by various constituents. Loss allocation on EHV network to the various constituents is also done. Actual data of power flows over the EHV network of Western regional grid for one day is considered. [ABSTRACT FROM AUTHOR]

Examines the optimal bidding for generating companies in a deregulated power market based on the Markov decision process (MDP). Role of energy auction in the deregulated power system; Types of energy auctions; Discussion on MDP.