The efficacy and practical relevance of the solution of any technical problem depends not only upon effective formulation of an objective function, but also on the choice of constraints, which limits the solution space, and same is the case with distribution network expansion planning (DNEP) problems as well. The objective functions of DNEP problems need to be bound by appropriate technical, social and economic constraints to arrive at the optimal solution for any site. Constraints are the conditions imposed in DNEP on various objective functions to achieve the most cost-effective, consistent and environment-friendly optimized solution. Hence the choice of appropriate constraints has a significant role in the execution of DNEP problems effectively. The present work aims to summarize the constraints considered in more than eighty selected original articles published over a decade. The constraints considered by various eminent researchers have been discussed by classifying them into technical, non-technical, time & financial and miscellaneous constraints. Special considerations required for deciding constraints for DNEP concerning assimilation of distributed generation (DG) and distributed energy storage system (DESS) have been discussed as well. The summary of constraints, through comprehensive review of the gigantic volume of literature on DNEP published over the past decade will help enduring and budding researchers in this field, pinpointing any breaks in reviewed literature that can be address in impending research for further enhancement and can be employed to arrive at an optimum solutions to DNEP problems.

中文翻译：

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有效的分销网络扩展计划的局限性：充分审查

解决任何技术问题的有效性和实用性不仅取决于目标函数的有效制定，还取决于约束条件的选择，这限制了解决方案的空间，配电网扩展计划（DNEP）的情况也是如此。问题。DNEP问题的客观功能需要受到适当的技术，社会和经济限制，才能为任何场所提供最佳解决方案。约束是DNEP对各种目标函数施加的条件，以实现最具成本效益，一致且环境友好的优化解决方案。因此，选择合适的约束条件对有效执行DNEP问题具有重要作用。本工作旨在总结十年来发表的80多篇精选原始文章中考虑的限制因素。讨论了各种杰出研究人员考虑的约束，方法是将其分为技术，非技术，时间和财务以及其他约束。还讨论了确定有关分布式发电（DG）和分布式能量存储系统（DESS）同化的DNEP约束所需的特殊注意事项。通过全面回顾过去十年中有关DNEP的大量文献，对制约因素进行了总结，这将有助于该领域的持久且萌芽的研究人员，