How to make solar power energy management system
Overall, the photovoltaic power generation system is designed according to four systems:
(1) Photovoltaic power generation system;
(2) Energy storage system;
(3) Intelligent power distribution system;
(4) Energy management system.
And in this article, let’s focus on the energy management system.
EMS system provides data management, monitoring, control and optimization for micro-grid dispatching and control, and ensures the stable and efficient operation of optical storage and wood complementary off-grid system.
It also provides power and voltage setting points for each energy controller in the energy storage system.
The EMS system not only can ensure that the thermal load and electrical load requirements of the system are met; but also ensure that the system meets the operation protocol between the main network system. And minimize energy consumption and system loss as much as possible.
Chapter 1: Energy Management System Network structure
The intelligent energy management and control system of this project adopts distributed structure design. The whole system is shown in the figure below:
One thing that needs to be reminded is that the structural design of each project needs to start from actual situation.
①DC/DC converters, environmental monitors and equipment in the energy storage container including BMS, electricity meters and air conditioners are connected to the data collector through RS。
②PCS directly access the switch.
③Fire and environmental alarm signals (e.g. flood, smoke, etc.) are connected to THE IO controller.
④The gateway and IO controller are installed near the communication management unit in the system control cabinet and connected to the switch through the network cable.
⑤Data collector and IO controller are DC power supply equipment, which shall be equipped with a switching power supply to convert AC power to 24V DC power.
⑥EMS hosts and industrial Ethernet switches are centrally installed in the EMS cabinet. Meanwhile, UPS is installed in the cabinet to provide power protection for these devices in order to avoid the impact of unexpected power failure on system operation.
⑦At the same time, an independent smart energy management host is set up for smart energy management portal and energy saving management server, and the printer is connected to the smart energy management host for report printing.
Chapter 2: Energy Management System Data Collection and Processing
The EMS system is capable of real-time and timed data acquisition of all monitored operation parameters and states, ac sampling is adopted for all electrical volumes, high precision and high speed are ensured, and important historical data are processed and stored in the database.
Firstly, EMS collects common information such as total voltage, current, average temperature, SOC, SOH, charging and discharging current and power limits, single battery voltage, single battery temperature, equilibrium state of each battery, fault and alarm information, historical charge and discharge quantity, historical charge and discharge electric energy of each battery in THE BMS system.
Secondly, EMS samples PCS of related parameters, including: dc side voltage/current/power of each branch, every phase of the ac active power, reactive power, voltage, current, power factor, frequency and temperature of IGBT, RC filter, such as temperature, running state and alarm and fault information commonly used information, switch machine, such as control signal, equipment configuration parameters, day charge, discharge, cumulative charging quantity, cumulative discharge, etc.
Thirdly, EMS also collects the battery room environment including indoor and outdoor temperature, humidity, air conditioning operation status, smoke sense, water level, fire control controller and other alarm signals, alarm control signals, air conditioning parameter Settings, etc
Chapter 3: Energy Management System Graphic Monitoring
The system can display real-time dynamic of microgrid operation system diagram, equipment monitoring diagram, network communication status diagram, etc. The graphic monitoring screen can dynamically refresh to show the electrical test parameters, operation parameters and status parameters, and prompt the display of telemetry off-limit alarm. When the telemetry signal exceeds the preset threshold, the system will automatically prompt the off-limit alarm, and the corresponding remote measurement will turn red (the color can be configured by the user).
Through the monitoring client, users can conduct remote control, telemetry of the number of remote signals (division/combination), telemetry of remote signal blocking/unblocking, setting signs, suppressing alarms and other operations on the monitoring equipment.
Overall operation monitoring system diagram: main equipment shows that the micro grid (grid, load, PCS, BMS, photovoltaic) in the running state.
Grid monitoring chart: Display switch state grid, power grid three phase current, three-phase voltage, three-phase active power, three-phase reactive power, three phase frequency, three-phase power factor, etc.
Load monitoring chart: Display load switch state, load current, three-phase voltage, three-phase active power, three-phase reactive power, three phase frequency, three-phase power factor, etc.
PCS monitoring graph: Mainly shows the main data storage converter, for example, the dc side voltage/current/power, etc., each PCS of three-phase active power, reactive power, three-phase voltage, three-phase current, power factor, frequency, running state and alarm and fault information such as common information.
BMS monitoring graph: The battery pile system SOC, system voltage, the total current and the monomer maximum differential pressure, the maximum temperature difference, the biggest difference between monomer, monomer voltage minimum value of the maximum minimum temperature, monomer and charge and discharge status and alarm information, such as various battery group of voltage, current, SOC, packet switch state, single battery voltage and temperature.
Photovoltaic monitoring chart: Display the running state of DC/DC converter and three-phase voltage, three-phase current, three-phase active/reactive power, apparent power, power factor, operation time, today’s generation, etc.
Energy storage container monitoring graph: shows the container air conditioning, water, fire, battery fire extinguishing system running parameters and alarm information.
Network communication state diagram: display server running parameters and the terminal state of communication.
Chapter 4: Energy Management
EMS provides a variety of operation modes and load forecasting, anti-countercurrent control, software protection and other control functions for DC side PHOTOVOLTAIC energy storage power station.
If the system is connected to the grid, the energy generated by photovoltaic systems directly through the MPPT charge controller for battery charging, the battery is completely dependent on the charging system of photovoltaic power generation, power grid electricity is not for battery charging. When the power consumption is in peak period, the three-phase ALTERNATING current with voltage class of 0.4kV is converted by THE energy-storage converter PCS to supply power to the user’s load:
The system run off-grid, energy generated by photovoltaic systems in addition to the power supply to the user load, the rest of the power used to recharge the battery. In the morning, when the light is insufficient, the photovoltaic power generation and the energy storage system together supply power to the user’s load. At noon, when the light is sufficient, the photovoltaic system will supply power to the user’s load, and then charge the battery after consumption. When there is no light in the afternoon or evening, the energy storage system discharges and supplies the electrical energy required by the user’s AC load.
EMS is only one of the four system designs. If you are interested, you can directly click on the article(how to build a solar power system tutorial) to learn about the remaining three system designs. And, if any questions and needs, just directly contact our team at any time.