Photovoltaic System Solutions

Overview

Solar PV has become one of the most popular new energy recent years. Therefore, a whole solution for power generation monitoring and reflux monitoring to each parts of Solar PV power distribution system become necessary for both distributed and centralized Solar PV.

Applicaiton Scenarios

Distributed photovoltaic solution

Nowadays, grid companies usually require photovoltaic grid-connected systems to be irreversible, that is, the electricity generated by photovoltaic grid-connected systems is consumed by local loads, and excess electricity is not allowed to supply to the grid. The system can regulate power generation in order to prevent the photovoltaic grid-connected system from generating reverse power.

lSolution for PV anti-backflow

Grids Side - Grids' Overall 3-phase Incoming Circuit:

- 1* ACR10RH-D110RE4 3-phase Rogowski Coil Energy Meter

When the Solar PV Generated Power < House Load Consumed Power

(1)When the Solar PV Generated Power > House Load Consumed Power(1) When the solar PV generated power wasn't enough for house loads to consume. Grids will also distribute power to house load for consuming. So, in this situation, the house load total power consumption was consisted of 2 parts, solar PV generated power and grids distribution power.

(2) Girds power flow to house load for consuming was normally calculated as "forward active energy, EPI" and "postive active power, +kw" by #1 ACR10R energy meter.

Calculation logic (When Solar PV not Enough)

Diagram of "Forward Active Energy, EPI”

When the Solar PV Generated Power > House Load Consumed Power

(1) When the solar PV generated power was larger than house loads power consumtpion. The part of over-generated solar PV power will reflux/export to power transformer or grids. In this situation, solar PV power generation will be distributed to 2 part, to house loads and to power transformer or girds.
(2) Solar PV over-generated power which reflux/export to power transformer or girds was normally calculated as "backward active energy, EPE" and "negative active power, -kw" by #1 ACR10R energy meter.

Calculation Logic (Solar PV Over-generated)

Diagram of "Backward Active Energy, EPE"

Structure&Logic - To Solar Inverter [Take ADL3000-E for example]

(1) ADL3000-E energy meter also has a RS485 port [MODBUS-RTU protocol] which could be connected to Solar PV Inverter so that inverter could get the reading from ADL3000-E based on MODBUS-RTU protocol.

(2) Once the inverter get a reading of "backward active power [minus value]", the invert could automatically lower its power generation rates so that the over all Solar PV generated power won't be more than house load consumption. Thus Solar PV side won't have export to grids side and eventually realize zero export.

Note:

1. Solar PV inverter get reading of bidirectional active power of grids side from ADL3000-E based on RS485 [MODBUS-RTU]

2. Once inverter get the reading of backward active power [export], inverter will lower its power generation rates so that no more Solar PV over-generated power flow to grids side. [no more export power]

3.All the generation power control logic was decided by inverter, energy meter ADL3000-E only provide the reading of bidirectional active power. So the integration between ADL3000-E and inverter based on RS485 interface [MODBUS-RTU] protocol for get the reading of bidirectional active power must be done and inverter side must have this type of control logic. [When inverter

4. Communication Structure&Logic - To Solar Inverter [Take ADL3000-E for example] get the reading of backward active power, it will lower its power generate rate ]

lSolution for PV anti-backflow

ACR10R-D16TE 1-phase Energy Meter

- Metering: Bidirctional AC Metering 1-phase

- Rated Voltage: 220~264Vac L-N (45~65Hz)

- Rated Current: 120A AC [via paired CT]

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Certificate&Standard: CE

- Currently Integrated with: Ginlong, Fusite, Alpha ESS, etc.

ACR10R-D24TE4 3-phase Energy Meter

- Metering: Bidirctional AC Metering 3-phase

- Rated Voltage: 3x220~264Vac L-N & 3x380~456Vac L-L

(45~65Hz)

- Rated Current: 200A AC [via paired CTs]

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Currently Integrated with: Ginlong, Fusite, Alpha ESS, etc.

- Certificate&Standard: CE

ACR10R-D110RE4 3-phase Energy Meter

Metering: Bidirctional AC Metering 3-phase

- Rated Voltage: 3x220~264Vac L-N & 3x380~456Vac L-L

(45~65Hz)

- Rated Current: 1000A AC (via paired 3 pcs Rogowski CTs)

- Accuracy: Class 1.0 for active energy monitoring

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Certificate&Standard: CE

AGF-AE-D/200 1-phase 3-wire Energy Meter

- Metering: Bidirctional AC Metering 1-phase

- Rated Voltage: 120Vac L-N; 208/240Vac L-N

- Rated Current: 100A AC

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Currently Integrated with: Ginlong, SUNGROW, Growatt

etc.

ADL3000-E 3-phase Energy Meter

- Metering: Bidirctional AC Metering 3-phase

- Rated Voltage: 3x220~264Vac L-N & 3x380~456Vac L-L

(45~65Hz)

- Rated Current: 3x1(6)A AC (via CTs)

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Currently Integrated with: Ginlong, SUNGROW, etc.

- Certificate&Standard: CE; UL

PZ96L-E4/KC 3-phase Energy Meter

- Metering: Bidirctional AC Metering 3-phase

- Rated Voltage: 3x220~264Vac L-N & 3x380~456Vac L-L

(45~65Hz)

- Rated Current: 3x1(6)A AC (via CTs)

- Communicaiton: RS485 Interface, MODBUS-RTU Protocol

- Currently Integrated with: Huawei, etc.

- Certificate&Standard: CE

Centralized PV solutions

lSolution for Online Monitoring

1.Scenario Preset

(1) The scenario is based on a small on-grid Solar PV system without DC energy storage.

(2) In order to establish a complete monitoring system, we need to install a smart wireless 3-phase energy meter with bidirectional metering function on Grids Side [Need to monitor the girds' overall 3- phase incoming circuit so that we can monitor the total power consumption supplied from grids to

house loads and also monitor the over-generated reflux energy from Solar PV to grids or power transformer.]

(3) The reason why to choose wireless energy meter was because it could directly send data to Acrel IoT Energy Monitoring System without using a extra IoT Gateway. For separate installation, this will be more economic.

(4) Suppose grids sides incomming circuits is with rated current of 150A AC and rated voltage of 230Vac L-N&400Vac L-N.

2. Devices Deployment Plan

Grids Side - Grids' Overall 3-phase Incoming Circuit:

- 1* ADW300-4GHW/C Wireless 4G Energy Meter

- 3* AKH-0.66/K K-φ24 150/5 Split-core Current Transformer

3. Calculation Logic- When the Solar PV Generated Power < House Load Consumed Power

(1) When the solar PV generated power wasn't enough for house loads to consume. Grids will also distribute power to house load for consuming. So, in this situation, the house load total power consumption was consisted of 2 parts, solar PV generated power and grids distribution power.

(2) Girds power flow to house load for consuming was normally calculated as "forward active energy, EPI" and "postive active power, +kw" by #1 ADW300-4GHW energy meter.

Calculation logic (When Solar PV not Enough)

Calculation logic (When Solar PV not Enough)

4. Calculation Logic - When the Solar PV Generated Power >House Load Consumed Power

(1) When the solar PV generated power was larger than house loads power consumtpion. The part of over-generated solar PV power will reflux to power transformer or grids. In this situation, solar PV power generation will be distributed to 2 part, to house loads and to power transformer or girds.

(2) Solar PV over-generated power which reflux to power transformer or girds was normally calculated as "backward active energy, EPE" and "negative active power, -kw" by #1 ADW300- 4GHW energy meter.

Calculation Logic (Solar PV Over-generated)

Diagram of "Backward Active Energy, EPE"

5. Communication Structure&Logic

(1) 4G Communication could be served as one of the final data upstream methods by sending the data to cloud server deployed in Internet so that Acrel IoT System could be interact with these data collected by bottom metering devices like Energy Meter

(2) ADW300-4GHW/C Wireless 4G 3-phase Energy Meter has a built-in 4G communication module which allow it to directly send data to local 4G telecom tower through 4G signal based on MQTT and MODBUS-TCP protocol without using a extra 4G IoT Gateway.

(3) Each ADW300-4GHW/C has a 4G card tray for installing the 4G sim card which could be bought from your local 4G service provider.

(4) ADW300-4GHW/C also have a RS485 communication normally used for devices adjustment with Acrel ADW300 adjustment softare.

Platform Introduction

Acrel IoT Energy Monitoring System could be access in 2 different ways:
(1) Access through WEB on your computer. Access port: https://iot.acrel-eem.com/
(2) Access through APP on your mobile phone

(1) WEB Accesss (Computer):
Access Port: https://iot.acrel-eem.com/
Test Account Name: acrel
Test Account Password: 123456

(2) APP Accesss (Mobile):
Download Link: https://play.google. com/store/apps/details?id=com.acrel.iotems
Test Account Name: acrel
Test Account Password: 123456

Main Function of WEB side System:
(1) Solar PV Monitoring (2) Devices List (3) History Curve (4) Electricity Parameters Report (5)Energy Consumption Report (Daily, Monthly, Yearly) (6) User Report

(1) Solar PV Monitoring:
Overview of overall loads' power consumption, Solar PV total power generation, energy supplied by grids that consumed by loads, over-generated Solar PV power flux to grids or powertransformer.

(2) Devices List:
Showing the overall devices connected to Acrel System and were bond to certain project. SNcode, Online-Offline status, devices model and other necessaryinformation will be shown here.

(3) History Curve:
Showing the daily history data curve of all the data that could be collected anduploaded by energy meter or otherbasic metering devices.

Main Function of WEB side System:
(1) Solar PV Monitoring (2) Devices List (3) History Curve (4) Electricity Parameters Report (5)Energy Consumption Report (Daily, Monthly, Yearly) (6) User Report

(3) History Curve:
By selecting the items of "date" and "electricity parameter", platform can show the history curve of different data and date.

(4) Electricity Parameters Report:
All the electricity parameters that could be collected by certain energy meter will showed as a report here.

(4) Electricity Parameters Report:
Report on platform could be exported in "Excel" format to your computer for a brief storage when accessing the IoT EMS WEB platform.

Main Function of WEB side System:
(1) Solar PV Monitoring (2) Devices List (3) History Curve (4) Electricity Parameters Report (5)Energy Consumption Report (Daily, Monthly, Yearly) (6) User Report

(5) Energy Report (Daily):
This Interface show the daily energy consumtion report(calculated by forward active energy)

(5) Energy Report (Daily):
This daily energy report could be also export to computer in "Excel" format

(5) Energy Report (Monthly&Yearly):
Same as daily energy report, monthly and yearly energyreport could be also checked on platform and exported in "Excel" format.

Main Function of WEB side System:
(1) Solar PV Monitoring (2) Devices List (3) History Curve (4) Electricity Parameters Report (5)Energy Consumption Report (Daily, Monthly, Yearly) (6) User Report

(6) User Report:
A comprehensive user report including project overview, energy report, energy analysis and etc could be check onplatform

(6) User Report:
User report could be exported in "PDF" format into your PC for convenient check and storage.

(6) User Report:
User report support template customization inbuy-out service of Acrel IoT Energy Monitoirng System.

Main Function of APP side System:
(1) Devices List (2) History Curve (3) Electricity Parameters Report (4) Energy Trend (5) Energy
Consumption Report (Daily, Monthly, Yearly)
Noted: Since APP side and WEB side of Acrel IoT Energy Monitoring System share the same data, normally recommend our user to add the devices to their account using APP and check the data using WEB platform.