Sunburst chart is used to visualize hierarchical data, depicted by concentric circles. The circle in the centre represents the root node, with the hierarchy moving outward from the center. A segment of the inner circle bears a hierarchical relationship to those segments of the outer circle which lie within the angular sweep of the parent segment.
This is an open source visual. Get the code from GitHub: https://github.com/Microsoft/powerbi-visuals-sunburst