# A Hybrid State Estimator Based on SCADA and PMU Measurements for Medium Voltage Distribution System
## 5 Conclusions  
In order to improve the accuracy of state estimation and effectively track system states, this paper proposed a hybrid state estimator considering the integration of a limited number of PMU measurements and bad data in the DSSE. The following conclusions were obtained:  
1. Using the PMU measurements in the DSSE was necessary and fast-state tracking with LSE could guarantee the timeliness of real-time measurements and avoid the waste of the PMU measurements. However, the estimation results would be less accurate if the estimated bus or area was far from the installation of the PMUs. 2. The normalized residuals and adaptive thresholds could improve the estimation robustness of dealing with the bad data in real-time measurements. 3. The proposed hybrid state estimator could effectively converge and quickly track the system states while ensuring the estimation accuracy. **Author Contributions:** [PERSON] and [PERSON] conceived the idea of the study and conducted the research. [PERSON] and [PERSON] analyzed most of the data and wrote the initial draft of the paper. [PERSON], [PERSON], and [PERSON] contributed to finalizing this paper. **Funding:** This research was funded by the National Key Research and Development Program of China grant number 2017 YFB0902900 and 2017 YFB0902902. **Conflicts of Interest:** The authors declare no conflict of interest. Figure 12: Performance of the proposed method: (**a**) the estimation error curve of voltage amplitude, and (**b**) the estimation error curve of voltage angle. * [PERSON] et al. (2017) [PERSON]; [PERSON]; [PERSON] Energy Big Data Security Threats in IoT-Based Smart Grid Communications. _IEEE Commun. Mag._**2017**, _55_, 70-75. [CrossRef]
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