Abstract-The thermal capacity of the content in a cold storage room renders it possible to shift the governing refrigeration system's power consumption in time, without compromising temperature constraints. In this paper we introduce a method of implementing such a cold storage room into a directly controlled smart grid, by use of a predictive control strategy. In this application the shift in consumption is used to stabilize a small grid by utilizing excess renewable energy to minimize the need for fossil fueled production sources. In order for the centralized grid controller to handle such a node, its flexibility is communicated in form of a simple generic bucket model. Finally, the provided experiments verify the effectiveness of the proposed method.

In this work, control strategies for aggregation of a portfolio of supermarkets towards the electricity balancing market, is investigated. The supermarkets are able to shift the power consumption in time by pre-cooling the contained foodstuff. It is shown how the flexibility of an individual supermarket can be modeled and how this model can be used by an aggregator to manage the portfolio to deliver upward and downward regulation. Two control strategies for managing the portfolio to follow a power reference are presented and compared. The first strategy is a non-convex predictive control strategy while the second strategy consists of a PI controller and a dispatch algorithm. The predictive controller has a high performance but is computationally heavy. In contrast the PI/dispatch strategy has lower performance, but requires little computational effort and scales well with the number of supermarkets. Two simulations are conducted based on high-fidelity supermarket models: a small-scale simulation with 20 supermarkets where the performance of the two strategies are compared and a largescale simulation with 400 supermarkets which only the PI/dispatch controller is able to handle. The large-scale simulation shows how a portfolio of 400 supermarkets successfully can be used for upward regulation of 900 kW for a two hour period.

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Abstract-During minimal invasive telesurgery with surgical robots, surgeons rely on their vision to determine the forces applied to tissue. A force-feedback control system has been developed, in order to reduce the unnecessary forces applied by the surgeon. To avoid adding any additional hardware, the forces in the system have been estimated on the basis of the existing actuators, using parameter estimation techniques. The inevitable time-delays in the network, which imposes challenges in control design, are also estimated and compensated for within the control design.During tests, it has been shown that it is possible to implement a distributed networked controller, which is stable over a range of typical time-delays. This shows, that the applied parameter estimation technique is indeed a viable solution for implementing force-feedback in telesurgery.