An efficient multiple access scheme for voltage control in smart grid using WiMAX

An efficient WiMAX-based multiple access scheme for the state updating in voltage control is introduced. The scheme, called sample-contention scheme, addresses the problem of optimally bringing deviated voltage to a predefined reference level with minimum communication resources by taking advantage of the sparseness of voltage disturbance. An n-sample interval is defined, in which randomly selected voltage monitors broadcast their voltage states and help other unselected ones prioritize transmissions of voltage-state-report using the Maximum Likelihood Estimation (MLE). By analyzing the successful transmission in contention access interval (m-contend), a contention based multiple access is devised. Numerical simulation results show that the sample-contention scheme can reduce the control cost by 20%, compared with the simple round-robin scheduling scheme.