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The paper presents an optimal power flow (OPF) formulation using an AC power system model based on current nodal analysis. One of the principle advantages of the proposed formulation is all components of the OPF problem are quadratic, which results in a constant Hessian matrix. The proposed model is compared to the traditional models using interior...

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Context 1
... relationship between the currents defined in equa- tions (7) and (8) and the nodal voltages which will be the principle variables in the OPF formulation are easily de- fined using traditional techniques. For example, the trans- mission line branch currents (as illustrated in Figure 1) can be written as: For the proposed formulation, the relationship be- tween the complex current associated with transformers and the bus voltages is derived by modeling the trans- former as an ideal transformer in series with a series impedance as illustrated in Figure 2. To ensure that power system model remains quadratic, two additional current and voltage variables are introduced as follows: are introduced to simply the equations describing the current voltage relationship at the sending and receiving buses. ...
Context 2
... pi model is used to incorporate the shunt capacitance to ground. Using equations (12) and (13), Figure 2, and the transmission line equations (10) and (11), the volt- age/current relationship for the transformer branches can be written as follows: ...

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