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The purpose of studying the low voltage direct current (DC) microgrid, which uses computerised control system techniques, an orderly coordination control stratagem considering optimisation of a hybrid energy storage system (HESS) was projected in this paper.

The projected control stratagem was divided into three levels: topmost power dispatch level, transitional bus voltage regulation level and bottommost converter control level.

At the topmost power dispatch level, the cost of system stability was introduced, which is related with state of charge and discharging power of HESS.

Furthermore, the cost of system stability and HESS depreciation was compared with commercial price, and HESS switches its operating mode to discharge more at higher price or charge more at lower price to ensure the DC microgrid in economic operation. At the transitional bus voltage regulation level, DC bus gesturing is used as a control signal to achieve an autonomous decentralised operation of DC microgrid. The Matlab/Simulink simulation inveterate that the economical and autonomous decentralised operation can be achieved through the control stratagem.

Existing control circuits for piezoelectric energy harvesting (PEH) suffers from long startup time or high power consumption. This paper aims to design an ultra-low power control circuit that can harvest weak ambient vibrational energy on the order of several microwatts to power heavy loads such as wireless sensors.

A self-powered control circuit is proposed, functioning for very brief periods at the maximum power point, resulting in a low duty cycle. The circuit can start to function at low input power thresholds and can promptly achieve optimal operating conditions when cold-starting. The circuit is designed to be able to operate without stable DC power supply and powered by the piezoelectric transducers.

When using the series-synchronized switch harvesting on inductor circuit with a large 1 mF energy storage capacitor, the proposed circuit can perform 322% better than the standard energy harvesting circuit in terms of energy harvested. This control circuit can also achieve an ultra-low consumption of 0.3 µW, as well as capable of cold-starting with input power as low as 5.78 µW.

The intermittent control strategy proposed in this paper can drastically reduce power consumption of the control circuit. Without dedicated cold-start modules and DC auxiliary supply, the circuit can achieve optimal efficiency within one input cycle, if the input signal is larger than voltage threshold. The proposed control strategy is especially favorable for harvesting energy from natural vibrations and can be a promising solution for other PEH circuits as well.

THE period of 40 years since man first flew with the aid of an internal combustion engine has seen many changes in aircraft power units. Power has increased to an astonishing extent, yet reliability has also been obtained. Unfortunately, however, the amount of skill and knowledge required to obtain the best results from an engine can hardly be said to have decreased.

This chapter explores social control from a theoretical perspective based on rhetoric. The chapter highlights three theorists whose insights enable us to see how social control functions. First, the chapter examines the work of Michel Foucault, in particular his notions of power, as they relate to the way social control operates. Second, key concepts from Antonio Gramsci reveal the ways in which social control discursively sustains its hold on society. Finally, the work of Louis Althusser is discussed, especially his notion of interpellation, as it yields a way to view how ideology and social control are interrelated rhetorically. By focusing on the rhetoric of social control, we can gain an understanding of how social control operates and is used by particular agents in society.

This chapter is about how leaders attempt to move from traditional to shared leadership and why they often cannot. We develop a new theoretical framework to examine whether leaders are willing to shift control from themselves to their followers and thus promote shared leadership in their teams. We argue that control shifts, while necessary for shared leadership, are particularly difficult for leaders to enact. This is because leadership is often closely bound with power and status in the organization, a reality of organizational life that is often overlooked in the quest for new forms of leadership, such as shared leadership. Our contribution lies in examining leaders’ ability to enact shared leadership through the lenses of primary and secondary control, and situating control shift in the context of global leadership including selected cultural dimensions, complexity, and paradoxes.

The purpose of this paper is to examine the impact of mediated power asymmetry on relational risk perception and modes of governance mechanism (intention‐based trust and unilateral control).

Survey research was conducted to collect data from 112 new product development (NPD) relationships and structural equation modeling was conducted to test the hypotheses.

The results suggest that benefiting from mediated power asymmetries by a firm is positively related to the relational risk perceived by its partner firm. This perception influences intention‐based trust to partner firm negatively and exercising of unilateral control positively. It was also found that the relationship between mediated power asymmetry and governance modes is mediated by relational risk perception.

This paper enhances the understanding of NPD relationships by examining the key mechanisms through which governance decision modes are influenced. In particular, the paper shows how mediated power asymmetries through affecting relational risk perception influence two governance modes including intention‐based trust and unilateral control.

To assess the weight and extent of control possessed by manufacturers over category management (CM) tactics in contemporary distribution channels for fast‐moving consumer goods; and to analyse the origins of this control.

A survey study conducted among Finnish manufacturers of fast‐moving consumer goods. A total of 420 questionnaires were sent out. Of these, 84 questionnaires were returned, of which 83 were satisfactorily completed for use in the analysis.

The study reveals that manufacturers believe that retailers are clearly in charge of CM tactics. However, large manufacturers seem to possess a relatively strong weight of control in CM decision making, whereas small manufacturers possess little weight of control. The origins of manufacturers' control are mostly non‐coercive in nature.

This study has approached CM from the perspective of manufacturing organisations. The phenomenon could also be approached from the retailers' or a dyadic perspective. It would be fruitful to conduct comparative studies in other national settings. Conceptual and qualitative empirical studies are needed to obtain a clearer understanding of the phenomenon.

The study suggests that manufacturers who wish to gain some control over CM tactics should base their interaction with retailers on expertise and issues related to referent power bases.

This paper offers new perspectives on CM by examining the concept of power within manufacturer‐retailer relationships.

This paper aims to clarify voltage sourced converter’s (VSC’s) influence rules on the alternating current (AC) short-circuit current and identify the key factors, so as to propose the short-circuit current suppression strategy.

This paper investigates the key factors which impact the short-circuit current supplied by the VSC based on the equivalent current source model. This study shows that the phase of the VSC equivalent current source is mainly affected by the type of fault, whereas the amplitude is mainly decided by the control mode, the amplitude limiter and the electrical distance. Based on the above influence mechanism, the dynamic limiter with short-circuit current limiting function is designed. The theoretical analysis is verified by simulations on PSCAD.

The short-circuit current feeding from VSC is closely related to the control mode and control parameters of the VSC, fault type at AC side and the electrical distance of the fault point. The proposed dynamic limiter can make VSC absorb more reactive power to suppress the short-circuit current.

The dynamic limiter proposed in this paper is limited to suppress three-phase short-circuit fault current. The future work will focus more on improving and extending the dynamic limiter to the fault current suppression application in other fault scenarios.

The research results provide a reference for the design of protection system.

The key influence factors are conducive to put forward the measures to suppress the fault current, eliminate the risk of short-circuit current exceeding the standard and reduce the difficulty of protection design.

Induction heating applications aided by power electronic control have become very attractive in the recent past. For cooking applications, power electronics circuits are very suitable to feed power to multi loads with an appropriate control technique. The purpose of this paper is to develop a three leg inverter to feed power to three loads simultaneously and independently.

Pulse density modulation control technique is used to control the output power independently with constant switching frequency.

Multi-load handling converter with independent power control is achieved with reduced number of switching devices (two switches/per load) with simple control strategy.

The proposed system is simulated in MATLAB/Simulink, and the thermal analysis is carried out in COMSOL multi-physics software. The hardware realisation is performed for a 1 kW prototype with 20 kHz switching frequency and 10 kHz pulse density modulation frequency. PIC16F877A microcontroller is used to validate the experimental results for various values of control signals (D_PDM). The simulation and experimental results are in good agreement and validates the developed system.