This chapter studies a singular case of Optimal Control Problems(OCPs) governed by a class of switched control systems. We proposea new mathematical formalism for this type of switched dynamic systemsand study OCPs with a quadratic cost functionals. The original sophisticatedoptimization problem is next replaced by an auxiliary “weaklyrelaxed” OCP. Our main result includes a formal proof of the local convexityproperty of the obtained auxiliary OCP. The convex structure ofthe OCP implies a possibility to apply a variety of powerful and relativelysimple optimization schemes to the sophisticated singular OCP involvingswitched dynamics. The conceptual numerical approach we finallydevelop includes an optimal switching times selection (“timing”) and asimultaneous optimal switched modes sequence scheduling (“sequencing”).