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

下一代存储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与电网所需之间的差异。这既包括长期事件(将能源从发电时转移到几个小时后使用)，也包括短期事件(提供电网支持服务，以保持照明)。英国电网是一个遗留系统--它的设计假设是，电网支持服务和每秒一秒的功率平衡由大型中央发电机组承担，通常是数百兆瓦的大型中央发电机组。然而，未来像飞轮这样的储能装置将不会是一个500兆瓦的飞轮在一个点上连接：储能装置将是大约500个1兆瓦的独立单元，单独连接或以少量单元的集群连接。为了使这样的系统与传统电网连接并工作以支持遗留电网，接口系统(电力电子和控制)必须设计成与存储单元的新动态和电网的遗留要求一起工作。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，以使组合系统能够表现为协调的内聚系统。本地单位将无法监督更广泛的网络的运行情况或其他单位的行为，因此整体系统性能在最好的情况下将是次优的，在最坏的情况下，个别单位可能最终会相互争斗-对系统应用相互矛盾的控制努力。在使用点的控制动态需要是快速的，既能严格控制现代电力电子所需的电流，又能在具有大量电力电子接口发电和低惯性的新系统中实现快速响应。本项目将研究电力电子接口及其本地控制的设计，同时考虑飞轮和压缩空气储能。它将审查协调这类系统所需的监督控制和电信要求、电网支助服务方面所需的创新，并将制定提供所需服务的新方法。并将研究使用与监控系统、网络仿真和本地控制器系统单元耦合的实时数字仿真器(RTDS)来实现此类系统的实际限制。

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.