Danny Morton

Traditionally, financial risk management is examined with cartesian and interpretivist frameworks. However, the emergence of complexity science provides a different perspective. Using a structured questionnaire completed by 120 Risk Managers, this paper pioneers a comparative analysis of cartesian and complexity science theoretical frameworks adoption in sixteen Zimbabwean banks, in unique settings of a developing country. Data are analysed with descriptive statistics. The paper finds that overally banks in Zimbabwe are adopting cartesian and complexity science theories regardless of bank size, in the same direction and trajectory. However, adoption of cartesian modeling is more comprehensive and deeper than complexity science. Furthermore, due to information asymmetries, there is diverging modeling priorities between the regulator and supervisor. The regulator places strategic thrust on Knightian risks modeling whereas banks prioritise ontological, ambiguous and Knightian uncertainty measurement. Finally, it is found that complexity science and cartesianism intersect on market discipline. From these findings, it is concluded that complexity science provides an additional dimension to quantitative risk management, hence an integration of these two perspectives is beneficial. This paper makes three contributions to knowledge. First, it adds valuable insights to theoretical perspectives on Quantitative Risk Management. Second, it provides empirical evidence on adoption of two theories from developing country perspective. Third, it offers recommendations to improve Quantitative Risk Management policy formulation and practice.

As the amount of decentralised generation is continuously increasing, the control and maintenance of grid stability become more complex. This is mainly caused by a change of production capacities from the high-voltage area to the distribution network. As most renewable energy sources in the distribution network are nowadays connected to power electronic converters, harmonic distortion as well as asymmetries (electric vehicle chargers, household photovoltaic systems) are increased. To ensure stability, reliability, and efficiency of the energy distribution network, a grid regulator including asymmetrical and harmonic control is introduced. This grid regulator consists of two inverter systems, where one is connected by a series booster transformer in line, while the other is connected in parallel to the line, capable of decoupling network segments from each other. After a successful verification in simulation, the control structure is implemented in a real hardware setup. The results show that the introduced system is able to decouple network elements in case of an unbalanced situation as well as harmonic current and voltage distortion. To simplify inverter hardware a silicon carbide hardware topology is introduced with a reduced number of switches. Lower switching losses result in higher overall system efficiency.

As the amount of decentralized generation is continuously increasing the controlling and maintaining of grid stability becomes more complex. This is caused by a change of production capacities from the high voltage area into the distribution network. In order to ensure stability of future smart grids a new 3-Level 4-Leg inverter as a part of a power electronic regulator is introduced. This topology is compared to a 3-Leg 4-Wire (3L4W) operation mode with focus on harmonic injection method. The difference between THD and efficiency is evaluated. As a result the 4L4W operation with harmonic injection can increase efficiency in most operation points. The THD is reduced in all test cases compared to the 3L4W operation. Additionally the overall flexibility is increased by an increased DC-Link voltage operation range.

The concept of smart grids has been widely introduced to cope with energy transition towards sustainable energy system, which results in decentralization of the energy supply system. Among various solutions to accomplish the smart grids, clustering power systems approach (CPSA) has been proposed. Based on this approach, active interconnected cluster areas, operating similar to interconnected grids in transmission systems, are created in bottom-up direction from distribution level upwards to the upstream systems. In order to manage emerging cluster areas and concurrently facilitate their cooperation, this paper proposes hybrid framework of management systems. That is, both centralized and decentralized management systems are employed for operations under the CPSA. Besides, to add a level of cyber security, this paper also presents the integration of the adapted access control mechanism based on XACML data-flow model to the management systems. Lastly, the applications of the proposed hybrid framework are illustrated and discussed in use cases.

The share of decentralized power generation is increasing, which causes general changes and challenges for the conventional power system. Hence, distribution system operators (DSO) need new technologies to ensure the stability of the entire electrical power system. As a feasible solution for structuring power networks, the Clustering Power System Approach (CPSA) has been introduced, providing an innovative and reasonable way of decentralisation for future-oriented power systems. With this approach, based on the Cluster Fractal Model, the stabilization of the power systems can be realized in a bottom-up direction from decentralized generation units in distribution grids to the upstream transmission grids. However, to accomplish smart operations in such decentralized and intelligent electricity networks an appropriate strategy for the interoperation between cluster areas is needed. To realize this concept this paper proposes a real-time orchestration system as a core functionality of Smart Grid Cluster Controllers (SGCC) to run the distribution control and management functions. Hereby, the characteristic needs of such functions inside or between clusters can be taken into account. Structural or hierarchical dependencies of the functions can also be considered. Lastly, the SGCC is implemented on different hardware platforms.

Decentralized, renewable energy sources has grown fast as a sustainable and clean alternative energy to overcome the carbon emissions caused by conventional power plants. However, this change leads to several challenges related to grid control, resulting in a need of new smart grid concepts. Therefore, Clustering Power System Approach (CPSA) has been introduced as a suitable smart grid concept. Meanwhile, the impact of small prosumers in power supply operation increases continuously and they will emerge from being passive to become active participants in smart grid and smart market operation. In a previous paper genetic algorithms (GA) has been introduced as an adequate optimization technique tackling the issue of economic optimization of smart prosumers in a case study. In this paper a case study for a whole cluster network with smart prosumers/households operating under individual requirements is carried out. Additionally, a market model containing auction based local energy markets (LEM) suitable to be implemented in the CPSA is introduced. This is the next step to achieve the goal of smart grid and smart market under the foundation of the CPSA. The results show that the GA based optimization in combination with the involvement of LEM provides economic benefits for smart prosumers.

Due to the trend of decentralized generation (DG) residing in low voltage distribution network, more inverters are connected to the grid in three-phase four-wire systems under asymmetrical condition. This paper presents an algorithm to balance DC-link capacitor voltages and minimize switching loss of three-level four-leg inverters which is suitable for asymmetrical condition. The algorithm is based on three-dimension space vector modulation (3D-SVM) in natural coordinates. The algorithm balances DC-link capacitor voltages by the selection of redundant standard vectors. Switching sequences are selected to minimize switching loss. Simulation results show that the method is able to balance DC-link capacitor voltages and reduce middle point voltage ripple.

The increase of electricity demand has raised requirements of more reliable and efficient grid operations as well as higher security of supply. Meanwhile, the transition towards clean and sustainable energy supply systems in the present power systems is under the spotlight [1]–[3]. High penetration of renewable energy sources (RESs), which are usually in the form of distributed generation (DG), can be expected. The RESs-based DG units can reside in distribution level, whose original purpose is to distribute power from electricity utilities to end users. Presently, to cope with the power penetration in distribution level, conventional power grids are being evolved into the smarter ones, known as smart grids. A smart grid is proposed to overcome the arising environmental and technical challenges [4], [5]. To smarten the grid, information and communication technologies are incorporated into the conventional power grids. They allow the cooperation of heterogeneous grid components, e.g. control centers and DG units, or users, e.g. operators and customers. Decentralization of grid control architecture is possible [6], and many actors can actively participate in the operation of the grid.

As the amount of decentralized generation is continuously increasing the control and maintaining of the grid stability becomes more complex. This is caused by the change of production capacities from the high voltage area into the distribution network. In order to ensure the stability of future smart grids a new 4-leg 4-wire inverter as a part of a power electronic regulator is introduced. The features of the 4-leg 4-wire topology in comparison to the 3-leg 4-wire topology and advantages of a multilevel inverter for harmonic compensation are shown. In combination with a powerful FPGA based controller complex algorithms for Space Vector Modulation and for control can be implemented. Finally the actual status of the hardware development including the technical data of the inverter is shown.

The penetration of distributed energy resources in distribution networks leads to the decentralisation of the power generation. This is contrary to the traditional centralized power generation where the power is fed from transmission systems. To cope with the impact of the decentralised power generation, clustering power systems approach (CPSA) is proposed. It is an approach that coexists operations of the distribution networks and the transmission systems by allowing the use of conventional control scheme and action of the transmission systems in the distribution networks. In addition, the CPSA is also aimed to realise the smart grid concept. Information and communication technology is hence applied to the CPSA. In this paper, a communication model and web services concept including its relevant technologies are proposed to enable power system operation based on the CPSA. The implementation of the communication model and web services for the CPSA is presented at the end.