## 1 Introduction  
To increase power supply efficiency and save costs, distributed renewable energy generation has been proposed. However, power generated using renewable sources is strongly influenced by weather, which produces intermittent power, and it cannot be directly used by the load and is also not easy to be fully stored. Thus, a microgrid becomes a good technology to solve the problem [1]. A microgrid is a power supply grid, which works in a small power range in comparison to a public grid. It can support decentralized power management and a liberalized electricity market to save wholesale costs [2, 3]. Renewable energy sources such as photovoltaic (PV) sources can directly produce direct current (DC) power to supply most electric appliances, and a DC microgrid [4, 5] can increase the efficiency of the power supply by decreasing the number of AC/DC converters. A hybrid microgrid can satisfy different electric appliances, but it is complex to control and to keep power balanced [6, 7]. According to the system architecture, microgrid control can be divided into decentralized control and centralized control, which can reach the same goal in different ways. However, decentralized control has an intrinsic advantage in flexibility. An example of decentralized control is using the multi-agent system [8, 9] consisting of many intelligent agents, which are composed of different architectures with different goals and communicate with each other to reach global goals [10]. As a classic control method, centralized control can make a power supply system comply with the design in detail [11; 12]. In order to distribute the power well to keep the power balanced among every component, power management for self-consumption, including source management, storage management, and load management, plays an important role in a microgrid with a fast calculation time. Mostly, renewable energy sources have the innate characteristic of intermittent power generation due to severe changes of the weather condition, which leads to difficult power generation and usage. Thus, reference [13] proposes a comprehensive control and power management system for PV-battery-based hybrid microgrids to be successful in regulating the DC and AC bus voltages and frequency stably for systems automatically under different operating circumstances, regardless of disturbances from switching operating modes and fluctuations of irradiance and temperature. However, the battery is regarded as storage that has a limited capacity, and limited charging and discharging current, which can lead to renewable power shedding, resulting in reducing the renewable energy usage rate. Thus, the public grid is mostly considered as an important power exchange interface to sell/buy power from the microgrid to achieve a low-cost operation between the microgrid and the public grid. The biggest advantage is the ability to achieve a low-cost power network grid when the multiply microgrid can be linked. Reference [14] developed a power control and management technique based on the bus signaling method to govern sources, storage, and loads to achieve effective coordination and energy management between microgrids. When the local public grid is not available or broken, the battery and renewable energy sources cannot afford the load demand power, and a backup source can be the emergency power source to support the important load. In [15], a dynamic power management scheme is proposed for a standalone hybrid AC/DC microgrid, which constitutes a PV-based renewable energy source, a proton exchange membrane fuel cell as a secondary power source, and a battery and a supercapacitor (SC) as hybrid energy storage to satisfy the different power exchange.