Energy Management in PV Wind Diesel Generator Battery System in MATLAB
Energy Management in PV Wind Diesel Generator Battery System in MATLAB
𝐈𝐧𝐭𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐨𝐧
The PV–Wind–Diesel Generator–Battery Energy Management System in MATLAB/Simulink demonstrates coordinated power management among renewable energy sources, battery storage, a diesel generator, and electrical loads.
The system is designed to study battery charging and discharging under two operating conditions:
Case 1: Varying solar irradiation condition
Case 2: Varying load condition
The battery reference current is automatically generated according to the selected operating case. A bidirectional converter then controls the battery power flow.
This MATLAB/Simulink model is useful for understanding hybrid renewable energy systems, battery energy management, PV control, DFIG wind generation, diesel generation, and grid-side inverter control.
𝐒𝐲𝐬𝐭𝐞𝐦 𝐎𝐯𝐞𝐫𝐯𝐢𝐞𝐰
The complete hybrid system consists of:
Solar PV generation
Battery energy storage system
Bidirectional battery converter
DC-link
Three-phase inverter
LC filter
Transformer
DFIG-based wind generation
Diesel generator
Three-phase loads
Energy management controller
PV MPPT controller
Inverter current controller
Main System Ratings
Component | Value / Description |
Solar PV rated power | 2 MW |
Wind generation | 3 MW |
Diesel generator | 5 MW |
System line voltage | 400 V |
Grid frequency | 50 Hz |
Case selection | 0 = Case 1, 1 = Case 2 |
Case 2 PV irradiation | 1000 W/m² |
First load switching time | 4.6 s |
Second load switching time | 9.2 s |
Simulation duration | 14 s |
𝐒𝐨𝐥𝐚𝐫 𝐏𝐕 𝐒𝐲𝐬𝐭𝐞𝐦
The solar PV array has a rated power of approximately 2 MW.
The PV block provides important electrical characteristics such as:
Maximum power
Open-circuit voltage
Voltage at maximum power point
Current at maximum power point
PV voltage
PV current
PV power
The PV characteristics can also be observed for different irradiation and temperature conditions.
The measured PV voltage and PV current are supplied to the MPPT controller for determining the required operating reference.
𝐁𝐚𝐭𝐭𝐞𝐫𝐲 𝐄𝐧𝐞𝐫𝐠𝐲 𝐒𝐭𝐨𝐫𝐚𝐠𝐞 𝐒𝐲𝐬𝐭𝐞𝐦
The battery is connected to the common DC-link through a bidirectional DC–DC converter.
The bidirectional converter allows energy transfer in both directions:
During excess generation, the battery operates in charging mode.
During insufficient generation or increased demand, the battery operates in discharging mode.
The model measures:
Battery current
Battery voltage
Battery power
Battery state of charge
These signals help analyze the battery response during different operating conditions.
𝐄𝐧𝐞𝐫𝐠𝐲 𝐌𝐚𝐧𝐚𝐠𝐞𝐦𝐞𝐧𝐭 𝐂𝐚𝐬𝐞𝐬
Two operating cases are implemented in the energy management controller.
Operating Case | Case Selector | Main Input | Battery Control Objective |
Case 1 | 0 | PV generation / irradiation variation | Charge or discharge according to available PV power |
Case 2 | 1 | Load power variation | Charge or discharge according to load demand |
A switching block selects the appropriate battery reference current according to the case selector.
𝐂𝐚𝐬𝐞 𝟏 – 𝐕𝐚𝐫𝐲𝐢𝐧𝐠 𝐒𝐨𝐥𝐚𝐫 𝐈𝐫𝐫𝐚𝐝𝐢𝐚𝐭𝐢𝐨𝐧
In Case 1, the main objective is to investigate battery operation when the solar irradiation changes.
The controller measures the PV current and generates a suitable battery current reference.
The general operating principle is:
High PV generation → Battery charging
Low PV generation → Battery discharging
Therefore, the battery absorbs excess solar energy during high-generation periods and supports the system during low-generation periods.
The load configuration remains fixed during this operating case.
𝐂𝐚𝐬𝐞 𝟐 – 𝐕𝐚𝐫𝐲𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐂𝐨𝐧𝐝𝐢𝐭𝐢𝐨𝐧
Case 2 investigates the response of the energy management system to changes in electrical load demand.
For this condition, solar irradiation is maintained at approximately 1000 W/m².
The load power is measured and converted into the required reference signal for the battery controller.
The general operating strategy is:
Higher load demand → Battery discharging
Lower load demand → Battery charging
This allows the battery to support the common bus whenever load demand increases.
𝐋𝐨𝐚𝐝 𝐒𝐰𝐢𝐭𝐜𝐡𝐢𝐧𝐠 𝐒𝐭𝐫𝐚𝐭𝐞𝐠𝐲
Three loads are connected to the system.
Two loads are controlled through circuit breakers to create load variations during Case 2.
Time | Switching Operation |
0 to 4.6 s | First controlled load remains disconnected |
After 4.6 s | First controlled load is connected |
0 to 9.2 s | Second controlled load remains disconnected |
After 9.2 s | Second controlled load is connected |
During Case 1, these controlled loads are maintained according to the fixed load configuration.
This arrangement creates clear changes in power demand for testing the battery energy management strategy.
𝐁𝐚𝐭𝐭𝐞𝐫𝐲 𝐂𝐨𝐧𝐯𝐞𝐫𝐭𝐞𝐫 𝐂𝐨𝐧𝐭𝐫𝐨𝐥
The selected battery reference current is compared with the measured battery current.
The resulting current error is processed through a PI controller.
The controller generates the required duty-cycle command, which is supplied to the pulse generator.
The generated switching pulses are applied to the two semiconductor switches of the bidirectional converter.
This control determines whether the battery operates in:
Charging mode
Discharging mode
Thus, the battery power flow automatically changes according to solar generation or load demand.
𝐏𝐕 𝐌𝐏𝐏𝐓 𝐚𝐧𝐝 𝐃𝐂-𝐋𝐢𝐧𝐤 𝐂𝐨𝐧𝐭𝐫𝐨𝐥
The PV system uses an MPPT controller based on measured:
PV voltage
PV current
The MPPT controller generates the required reference voltage.
This reference is compared with the measured DC-link voltage.
The voltage error is processed by the DC-link PI controller to generate the d-axis reference current.
This reference current becomes part of the inverter control system.
𝐆𝐫𝐢𝐝-𝐒𝐢𝐝𝐞 𝐈𝐧𝐯𝐞𝐫𝐭𝐞𝐫 𝐂𝐨𝐧𝐭𝐫𝐨𝐥
The inverter connects the DC system to the AC side through an LC filter and transformer.
The control system measures three-phase inverter voltage and current.
These three-phase signals are transformed into the dq reference frame.
The controller uses:
d-axis current reference
q-axis current reference
Actual d-axis current
Actual q-axis current
PI current regulators
Feed-forward compensation
The resulting dq control voltages are converted back into three-phase reference signals.
These reference signals are processed by the pulse generation system to produce the inverter switching pulses.
The inverter therefore manages the power transfer between the DC-link and the AC system.
𝐖𝐢𝐧𝐝 𝐄𝐧𝐞𝐫𝐠𝐲 𝐒𝐲𝐬𝐭𝐞𝐦
The wind generation system is rated at approximately 3 MW and uses a Doubly Fed Induction Generator (DFIG) configuration.
The DFIG consists of:
Wind turbine model
Drive train
Wound-rotor induction generator
Rotor-side converter
Grid-side converter
DC-link between converters
Speed regulation
Pitch control
The stator is directly connected to the common AC bus.
The rotor is interfaced through power electronic converters. This converter arrangement allows the rotor-side electrical power to be processed before being supplied back to the common coupling point.
The wind generation section therefore contributes renewable power to the complete hybrid system.
𝐃𝐢𝐞𝐬𝐞𝐥 𝐆𝐞𝐧𝐞𝐫𝐚𝐭𝐨𝐫
A 5 MW diesel generator is also connected to the common bus.
The diesel generator model includes both continuous and discrete configurations.
Its controller supports two main operating modes:
Control Mode | Controlled Quantities |
PQ Control | Active power and reactive power |
PV Control | Active power and voltage |
The demonstrated configuration uses the PV control mode.
The diesel generator model also contains generator and prime-mover-related control sections to regulate system operation.
It provides additional generation support to the hybrid power system.
𝐖𝐨𝐫𝐤𝐢𝐧𝐠 𝐏𝐫𝐨𝐜𝐞𝐬𝐬
The overall energy-management sequence can be understood as follows:
Solar PV, wind generation, and diesel generation supply the common electrical system.
PV voltage and current are continuously measured.
The selected operating case determines the battery reference-current calculation.
In Case 1, battery control depends mainly on PV generation.
In Case 2, battery control depends mainly on load demand.
The battery current controller controls the bidirectional converter.
Excess generation charges the battery.
Insufficient generation or increased load demand causes battery discharge.
The inverter controller maintains controlled power transfer between the DC and AC sections.
System quantities are monitored through multiple Simulink scopes.
𝐒𝐢𝐦𝐮𝐥𝐚𝐭𝐢𝐨𝐧 𝐑𝐞𝐬𝐮𝐥𝐭𝐬
The model is simulated for 14 seconds.
Different scopes are provided for observing the major system variables.
PV Results
The PV scope can display:
Irradiance
PV power
PV voltage
PV current
These signals show the response of the solar PV system to changes in irradiation.
Battery Results
The battery scope monitors:
Battery current
Battery voltage
Battery state of charge
Battery power
These results help identify battery charging and discharging operation.
Load Results
The load scope provides information such as:
Three-phase load voltage
Three-phase load current
Load power
THD-related response
The Case 2 results clearly demonstrate the system response when additional loads are connected at 4.6 s and 9.2 s.
Wind Results
The wind-generation scope can be used to observe the contribution of the DFIG-based wind energy system to the common bus.
𝐊𝐞𝐲 𝐅𝐞𝐚𝐭𝐮𝐫𝐞𝐬
2 MW solar PV generation
3 MW DFIG wind generation
5 MW diesel generator
Battery energy storage with bidirectional converter
Two energy-management operating cases
Irradiation-based battery control
Load-based battery control
PV MPPT
DC-link voltage regulation
dq-axis inverter current control
Feed-forward compensation
Dynamic load switching
Battery SOC monitoring
Three-phase voltage and current analysis
MATLAB/Simulink-based integrated hybrid energy system
𝐀𝐩𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬
This model can support the study of:
Hybrid renewable energy systems
Renewable energy integration
Battery energy management
Microgrid power management
PV–wind hybrid systems
Diesel-supported renewable systems
Battery charging and discharging control
Bidirectional DC–DC converters
DFIG wind energy conversion
Inverter control
DC-link voltage regulation
Variable generation and variable load analysis
𝐂𝐨𝐧𝐜𝐥𝐮𝐬𝐢𝐨𝐧
The Energy Management in PV Wind Diesel Generator Battery System in MATLAB provides a complete simulation framework for studying coordinated operation of renewable generation, battery storage, diesel generation, and changing electrical loads.
The two operating cases make the system particularly useful for understanding how a battery can support a hybrid power network under both changing solar irradiation and changing load demand.
With a 2 MW PV system, 3 MW DFIG wind system, 5 MW diesel generator, bidirectional battery converter, MPPT control, DC-link regulation, and inverter control, the model demonstrates the main control concepts required for hybrid energy management in MATLAB/Simulink.
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