The thesis covers the management of the consumption of various loads of the electricity
consumer in relation to the total consumption. Information on total consumption can be
captured in different ways.
When searching for a solution, we assumed that the information on the total electricity
consumption is already available or additional measuring device will be added. For controlling
the consumers we are choosing from a set of known consumers in which we can control the
consumption considering the total consumption.
Among the selected consumers, we focused on simple consumers that have the characteristics
of a pure ohmic load and controlled with voltage regulator. A typical example is a water heater,
which we replaced with a classic light bulb during testing.
We used a Raspberry Pi with a Linux operating system for the microcontroller. In addition to
power supply, we prepared the necessary signal and communication connections. We designed
a voltage regulator to control the load. The voltage at the output of the regulator depends on the
PWM signal at the input. We selected a measuring device from the manufacturer Iammeter,
which enables standard communication via the Modbus protocol and RS485 connection. We
assembled all the equipment on the panel. Due to the nature of the tests, we set up an
uninterrupted DC power supply with an auxiliary battery.
In addition to preparing the hardware, software development was also necessary. The main part
involves regulating the control of the load based on measurements of the total consumption and
predetermined current limits. The software is developed in the Python programming language
and runs on the microcontroller.
For the purpose of measuring specific currents, we prepared an independent measurement using
a multi-channel simultaneous measuring device and computer software to display values in
graphs. The real-time monitor of all currents provided a good representation of the controlled
regulation proces The testing results demonstrated the effective use of the selected solution. By
controlling the loads we can control the total electricity consumption. This is particularly
relevant when discussing real-time energy consumption produced by a solar power plant. We
can use the same solution when cutting peak energy consumption that are based interval of 15-
minute. By optimizing the controller, we can achieve quick responses within one second, which
offers additional benefits in limiting the current near the nominal limit of the fuses.
The mentioned solution, using the transfer of information of total current via a wide area
(WAN) or local (LAN) network, can be relevant in the design of electricity distribution through
integration into smart grids or virtual power plant.
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