Introduction

tellegen is a reactive visualization interface for power flow cases. The name refers to Tellegen’s theorem and the adjoint sensitivity calculations.

The app uses a gradient preview, exact commit interaction model. Perturbations update the display from KKT sensitivity columns. Exact solves (DC OPF, AC power flow, and the SOCWR relaxation) run in the browser in WebAssembly. Case parsing uses powerio.

Demo

The public demo at tellegen.dev serves three TAMU ACTIVSg synthetic grids and the CATS California Test System at their staged geographic coordinates. These are synthetic grids on geographic footprints, not surveyed infrastructure:

Each case solves as DC OPF by default; a selector switches to the SOCWR relaxation, solved in the browser in WebAssembly. Bus color shows locational marginal price. Selecting a bus shows the dLMP/dd column for a demand perturbation at that bus. Moving the demand slider applies the local sensitivity immediately; releasing it computes the exact solution in WebAssembly.

Local Files

Dropped .m, .raw, and .aux files are parsed in the browser by the WebAssembly build of powerio. Files with coordinates render on the map. Files without coordinates can be placed by clicking the map, or paired with local geographic files in .csv, .json, or .geojson form. A dropped PowerWorld .pwd file is decoded as display data and rendered as approximate substation positions. Parsed local case files solve in the browser and are not uploaded.

API

• GET /api/health
• GET /api/cases
• GET /api/cases/{id}/case
• GET /api/cases/{id}/network
• GET /api/cases/{id}/solution
• GET /api/cases/{id}/sensitivity/lmp/d/{bus}
• GET /api/cases/{id}/solve

The sensitivity and solve endpoints accept ?d=bus:mw,bus:mw, where each value is a MW delta from the base case. The solve stream emits status, solution, optional sensitivity, and done events.