## 1 Introduction  
Today, many types of distributed renewable sources, such as photovoltaic generation and wind power generation, have been installed in homes and communities. These sources lack the ability to supply power constantly because of the variability of the sources. For example, output from a photovoltaic system is strongly affected by weather conditions that cause fluctuations in frequency and voltage. In 1998, [PERSON] _et al._ proposed the concept of an open-electric-energy-network (OEEN) where power flow is controlled by multiple electric-energy-routers [1]. This power routing makes it possible for many types of dispersed power sources to participate in an electrical power market without disadvantages to existing power utilities and consumers. Unfortunately, the proposal was made too early to realize the system in those days. Conversely, electrical equipments that have built-in batteries, such as a mobile computer, does not always require high-quality input power. Therefore, more effective power consumption is expected by achieving appropriate source-and-load matching according to the ancillary quality of energy, such as frequency variation and voltage fluctuation [2]. In a conventional AC power distribution system, however, electricity from different power sources cannot be exactly separated in the same distribution line. In order to design a system that has the capability of achieving appropriate matching between sources and loads from a viewpoint of the quality of energy, a path control of power flow on the power distribution network has been investigated as a power routing system that prevents the mixing of powers from different power sources [3; 4; 5; 6]. This type of system is able to realize the concept of OEEN [1]. To establish the power routing system, our group developed a DC power packet dispatching system and an AC power router by applying highly developed power devices and information and communications technologies [5; 6; 7; 8; 9; 10]. The former is intended to realize a packet transfer in a network for electrical power distribution [5; 6; 7; 8; 9]. The latter is intended to realize a circuit matrix for establishing a power distribution circuit [5; 6; 10]. Power routing methods have been presented and developed by several groups independently. [PERSON] _et al._ have designed a universal power router [11], and [PERSON] _et al._ have proposed an electric power system with intelligent power switches based on the Internet and microgrids [12]. Conversely, in the cloud computing context, energy dispatched as a pulse, called an energy packet, is also proposed as a method to provide energy on demand to cloud computing servers [13; 14; 15]. In this study, the feasibility of an AC power routing network system consisting of multiple power routers is preliminarily investigated. Figure 1 shows a schematic diagram of the proposed AC power routing system. We have already developed the hardware for the power router that is able to achieve AC power routing by circuit exchanges [6; 10]. The details of the power router are explained in the following section. To evaluate the feasibility of the power routing network system, operations of power routers are experimentally verified in two configurations, _i.e._, parallel and series configurations. This is because any general network configuration can be classified into parallel and series connections. Simultaneously, we also verify the function of exchanging power lines (PLs) without the restriction of synchronization. This considers a case such as when the power conditioner for a photovoltaic source is driven independently of a commercial power network. Figure 1: Configuration of an AC power routing system. PLC: power line communication. This paper is organized as follows. In Section 2, a configuration of the AC power routing system and its functions are explained. In Section 3, the operation of the single AC power router is verified.