Multi-function Electric Power Monitoring Device Based On ARM And ADE7878

Electricity has become more and more indispensible in our daily lives. Therefore, how to ensure the stability and safety of power grid is of great significance. As a result, power grid parameter monitoring has become very important. Power monitoring device described in this paper is a multi-function power grid parameter monitoring panel, and is capable of monitoring the operation conditions of power grid.The core of this power grid parameter monitoring device is made up of LPC2214chip released by Phillips, which provides a high performance at a relatively low power consumption level, and ADE7878released by ADI, a dedicated power measurement chip. LPC2214is mainly in charge of reading measured values of power parameters acquired by ADE7878, sampling and analyzing of instantaneous current and voltage curves, and is also in charge of the implementation of human-computer interaction and other monitoring functions. Besides, this device carries a RS485communication interface, which can realize local and remote communication with host computer conveniently. ADE7878realizes the grid data sampling, and the computation of active power, reactive power, apparent power, current effective value and voltage effective value.Induction of power measurement development has been made first, and a summary of structures of common power measurement devices around the world is then given in this paper. After illustrating Measuring theories of basic power parameters, a specific introduction of software and hardware design of the multi-function power monitoring device is given in this paper. The main design scheme, together with software flowchart and specific hardware structure diagram are also provided. Hardware design includes sampling circuit, power source circuit, core circuit and display circuit, and software system is based on embedded real-time operation system-μC/OS-Ⅱ, which is transplanted on LPC2214processor. At last, an initial integration of each functional module has been made, and an accurate three-phase testing source is used to test the power monitoring device. Practical measurements showed that this multi-function power monitoring device provides a relatively high measuring accuracy, and is able to work stably and instantaneously. And this device also meets its design expectations.