# A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint

## Abstract

This paper examines the AC Optimal Power Flow (OPF) problem for multiphase distribution networks featuring renewable energy resources (RESs). We start by outlining a power flow model for radial multiphase systems that accommodates wye-connected and delta-connected RESs and non-controllable energy assets. We then formalize an AC OPF problem that accounts for both types of connections. Similar to various AC OPF renditions, the resultant problem is a non convex quadratically-constrained quadratic program. However, the so-called Feasible Point Pursuit-Successive Convex Approximation algorithm is leveraged to obtain a feasible and yet locally-optimal solution. The merits of the proposed solution approach are demonstrated using two unbalanced multiphase distribution feeders with both wye and delta connections.

- Authors:

- Publication Date:

- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)

- Sponsoring Org.:
- USDOE Advanced Research Projects Agency - Energy (ARPA-E)

- OSTI Identifier:
- 1369115

- Report Number(s):
- NREL/CP-5D00-68605

- DOE Contract Number:
- AC36-08GO28308

- Resource Type:
- Conference

- Resource Relation:
- Conference: Presented at the IREP 2017 Symposium, 27 August - 1 September 2017, Espinho, Portugal

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; optimal power flow; distributed energy resources; QCQP; successive convex approximation

### Citation Formats

```
Zamzam, Ahmed, S., Zhaoy, Changhong, Dall'Anesey, Emiliano, and Sidiropoulos, Nicholas D.
```*A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint*. United States: N. p., 2017.
Web.

```
Zamzam, Ahmed, S., Zhaoy, Changhong, Dall'Anesey, Emiliano, & Sidiropoulos, Nicholas D.
```*A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint*. United States.

```
Zamzam, Ahmed, S., Zhaoy, Changhong, Dall'Anesey, Emiliano, and Sidiropoulos, Nicholas D. Tue .
"A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint". United States.
doi:. https://www.osti.gov/servlets/purl/1369115.
```

```
@article{osti_1369115,
```

title = {A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint},

author = {Zamzam, Ahmed, S. and Zhaoy, Changhong and Dall'Anesey, Emiliano and Sidiropoulos, Nicholas D.},

abstractNote = {This paper examines the AC Optimal Power Flow (OPF) problem for multiphase distribution networks featuring renewable energy resources (RESs). We start by outlining a power flow model for radial multiphase systems that accommodates wye-connected and delta-connected RESs and non-controllable energy assets. We then formalize an AC OPF problem that accounts for both types of connections. Similar to various AC OPF renditions, the resultant problem is a non convex quadratically-constrained quadratic program. However, the so-called Feasible Point Pursuit-Successive Convex Approximation algorithm is leveraged to obtain a feasible and yet locally-optimal solution. The merits of the proposed solution approach are demonstrated using two unbalanced multiphase distribution feeders with both wye and delta connections.},

doi = {},

journal = {},

number = ,

volume = ,

place = {United States},

year = {Tue Jun 27 00:00:00 EDT 2017},

month = {Tue Jun 27 00:00:00 EDT 2017}

}