144 research outputs found
A Linear LMP Model for Active and Reactive Power with Power Loss
Pricing the reactive power is more necessary than ever before because of the
increasing challenge of renewable energy integration on reactive power balance
and voltage control. However, reactive power price is hard to be efficiently
calculated because of the non-linear nature of optimal AC power flow equation.
This paper proposes a linear model to calculate active and reactive power LMP
simultaneously considering power loss. Firstly, a linearized AC power flow
equation is proposed based on an augmented Generation Shift Distribution
Factors (GSDF) matrix. Secondly, a linearized LMP model is derived using GSDF
and loss factors. The formulation of LMP is further decomposed into four
components: energy, congestion, voltage limitation and power loss. Finally, an
iterate algorithm is proposed for calculating LMP with the proposed model. The
performance of the proposed model is validated by the IEEE-118 bus system.Comment: 6 pages, 6 figures, accepted by IEEE Sustainable Power & Energy
Conference (iSPEC2019
A unified framework of transformations based on the Jordan-Wigner transformation
Quantum simulation of chemical Hamiltonians enables the efficient calculation
of chemical properties. Mapping is one of the essential steps in simulating
fermionic systems on quantum computers. In this work, a unified framework of
transformations mapping fermionic systems to qubit systems is presented, and
many existing transformations, such as Jordan-Wigner, Bravyi-Kitaev, and parity
transformations, are included in this framework. Based on this framework, the
Multilayer Segmented Parity (MSP) transformation is proposed. The MSP
transformation is a general mapping with an adjustable parameter vector, which
can be viewed as a generalization of the above-mentioned mappings. Furthermore,
the MSP transformation can adjust flexibly when dealing with different systems.
Applying these mappings to the electronic structure Hamiltonians of various
molecules, the MSP transformation is found to perform better on the number of
Pauli operators and gates needed in the circuit of Hamiltonian simulation. The
MSP transformation will reduce the qubit gate requirement for Hamiltonian
simulation on noisy intermediate-scale quantum devices,and it will provide a
much wider choice of mappings for researchers
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