Interfacing Next-Generation Grid-Scale Storage to the Electrical Power Network (Inter-Storage)

下一代储能技术将在未来的电力系统中发挥关键作用，弥补低碳可持续发电所能提供的电力与电网需求之间的差距。这既包括长期事件（将能量从产生时转移到几个小时后使用时），也包括短期事件（提供电网支持服务以“保持供电”）。英国电网是一个遗留系统——它的设计是基于这样的假设：电网支持服务和每秒电力平衡是由大型中央发电机组承担的，通常是几百兆瓦的规模。然而，像飞轮这样的未来储能单元将不会是一个500兆瓦的飞轮在一个点上连接：存储将是500个每个1兆瓦的独立单元，单独连接或以少量单元的集群连接。为了使这些系统能够连接到传统电网，并支持传统电网，接口系统（电力电子和控制）必须设计成能够与存储单元的新动态和电网的传统需求一起工作。这意味着需要某种形式的监督控制来修改每个存储单元的本地接口控制，以使组合系统能够作为一个协调的内聚系统运行。一个局部单元将无法监督更广泛的网络的表现或其他单元的行为，因此整个系统的性能在最好的情况下将是次优的，在最坏的情况下，单个单元可能最终会相互争斗——对系统应用矛盾的控制努力。在使用点上的控制动态需要快速，以便能够严格控制现代电力电子所需的电流，并且能够在具有大量电力电子接口发电和低惯性的新系统中实现所需的快速响应。该项目将研究电力电子接口及其局部控制的设计，同时考虑飞轮和压缩空气储能。它将审查协调这种系统所需的监督控制和电信要求、网格支助服务所需的创新，并将拟订提供所需服务的新方法。它将研究使用实时数字模拟器（RTDS）与监控系统、网络仿真和本地控制器系统单元耦合实现这样一个系统的实际限制。

Next generation storage technologies have a key role to play in the future electrical power system, making up the difference between what low-carbon sustainable generation can provide, and what the grid needs. This is both in terms of longer term events (shifting energy from when it is generated to when it is used several hours later) and shorter terms events (providing grid support services to 'keep the lights on'). The UK electrical grid is a legacy system - it has been designed under the assumption that grid support services and second-by-second power balancing is undertaken by large central generating units, typically several hundred megawatts in size. However future energy storage units like flywheels will not be one 500 MW flywheel connected at one point: the storage will be something like 500 individual units each of 1MW, connected individually or in clusters of a small number of units. In order for such systems to interface to, and work to support the legacy grid, the interface system (power electronics and control) must be designed to work with the new dynamics of the storage unit and the legacy requirements of the electrical grid. This means that some form of supervisory control is required to modify the local interface control of each storage unit to enable the combined system to behave as a coordinated cohesive system. A local unit would not have an oversight of how the wider network is performing or the other units are behaving and thus the overall system performance would be at best sub-optimal, and at worst individual units could end up fighting with each other - applying contradictory control effort to the system. The dynamics of the control at the point of use would need to be fast to both enable the tight control of current required by modern power electronics, and to enable the fast response required in new systems with large amounts of power electronic interfaced generation and low inertia.This project will investigate the design of the power electronics interface and its local control, considering both flywheel and compressed air energy storage. It will examine the supervisory control and telecommunications requirements needed to coordinate such systems, the required innovations in grid support services, and will formulate new methodologies to provide the required services. And it will investigate the practical constraints of implementing such a system using a real-time digital simulator (RTDS) coupled to a supervisory control system, network emulation and local controller system units.