The needs for improving observability of medium and low voltage distribution networks has been significantly increased, in recent year. In this paper, we focus on practical approaches for placement of affordable Measurement Devices (MDs), which are providing three phases voltage, current, and power measurements with certain level of precision. The placement procedure is composed of a state-estimation algorithm and of a greedy placement scheme. The proposed state-estimation algorithm is based on the Distflow model, enhanced to consider the shunt elements (e.g., cable capacitances) of the network, which are not negligible in low voltage networks with underground cables. The greedy placement scheme is formulated such that it finds the location of minimum required number of MDs while certain grid observability limits are satisfied. These limits are defined as the accuracy of state-estimation results in terms of voltage magnitudes and line currents over all nodes and lines, respectively. The effectiveness of the proposed placement procedure has been validated on a realistic test grid of 10 medium voltage nodes and 75 low voltage nodes, whose topology and parameters were made available from the Distribution System Operator (DSO) of the city of Geneva, Switzerland.

近年来，对改善中低压配电网的可观察性的需求已大大增加。在本文中，我们将重点放在放置可负担的测量设备（MD）的实用方法上，这些设备可提供具有一定精确度的三相电压，电流和功率测量。放置过程由状态估计算法和贪婪放置方案组成。所提出的状态估计算法基于Distflow模型，经过增强后可以考虑网络的并联元件（例如电缆电容），而在带有地下电缆的低压网络中，并联元件是不可忽略的。制定贪婪放置方案，以便在满足某些网格可观察性限制的同时，找到最小所需MD数的位置。这些限制定义为状态估计结果的准确性，分别根据所有节点和线路上的电压幅度和线路电流来确定。建议的放置程序的有效性已在10个中压节点和75个低压节点的真实测试网格上得到了验证，其拓扑和参数可从瑞士日内瓦市的配电系统运营商（DSO）获得。