With the objective of maximum good measurement rate（GMR） while satisfying power flow equations and operational limits of state variables， a novel method for power system state estimation is proposed. The problem is solved using the interior point method with good convergence performance. Compared with existing state estimation methods， the method proposed has a higher GMR and better bad-data rejection performance. The resulting estimation based on the method is more realistic since it satisfies power flow equations and various physical constraints. The method does not ask for additional bad data checking， observability verification， or subjective weighting factors setting， thus achieving substantial reduction in debugging and maintenance workload. The effectiveness of the method proposed is proved by test results of the IEEE 39-bus system， the IEEE 118-bus system， and a practical utility system.