A Bisa Na Tabbacin Ƙanananin Da Take Da Aikacewa Da Tururuka Ta Zama Cikin Lantarki Da Tururuka Masu Iya Aiki Da Tururuka

1. Gaskiya da Tarihin Bincike​

​1.1 Hali na Yanzu a Tashar Solar​
A yadda take da zama tushen mai ban sha'awa a kan al'adun mutanen, harkokin da amfani da tashar solar ta zama muhimmanci a kawo gajerar jin daidai. A shekarun da suka baki, a kan sarukiyoyin duniya, tashar photovoltaic (PV) ta samu ci gaba mai zurfi. An sanya cewa tashar PV na Najeriya ta samu ci gaba 168-folds a lokacin "12th Five-Year Plan". A tsakiyar 2015, an yi amfani da tashar PV daga 40,000 MW, wanda ya zama mafi shahara a duniya har shekara uku, da ci gaban masu inganta a gaba.

​1.2 Masu Dabara da Kungiyoyin Fanni​
Idan ba haka, kungiyoyin PV da ke amfani da tashar solar suna da masu dabara a fannin da za a yi:

• ​Masana PV Array:​​ Don in iya tabbatar da sauki da abubuwa ga zabe, ana iya haɗa da PV cells da dama a kan series da parallel. Wannan yanayi na iya samun dabara saboda shading, wanda ya jawo "mismatch" losses da hot-spot effects, wanda ke magance ƙarfin tattalin abubuwa da kyau da tashar solar da kyau.
• ​Masana Battery Pack:​​ Ana iya haɗa da battery packs da dama a kan series da parallel, wanda ke magance masu dabara saboda balancing. In yi nasararsa game da scale, wanda ke magance ƙarfin tattalin abubuwa da kyau da tashar solar da kyau, da kuma ci gaban takalma da kyau.
• ​Kungiyoyin Da Ba Su Da Kyau:​​ Idan ba haka, wasu maimakon sun bayar da passive equalization management techniques, amma wannan tushen bayanai ba su iya taimaka da balancing problem ba, ba su iya taimaka da tashar solar da kyau, ba su iya taimaka da key components like PV cells ba.

​II. Tushen Jami'a da Topology​

Wurin tushen ya fi shi shine in kawo karfin topology mai karfi, modular, da kuma scalable.

​2.1 Hierarchical System Composition​
An haɗa da tushen hierarchical zuwa level da dama:

1. ​Module (Basic Unit):​​
• ​Composition:​​ Single PV cell, single storage battery (da voltage da capacity), 4 power switches, da independent controller.
• ​Function:​​ A nan shine smallest autonomous unit, controller ya taimaka da 4 switches don in iya haɗa da PV cell da battery, don in iya kawo ci gaban operating modes da dama.
2. ​Series String:​​
• ​Composition:​​ An haɗa da modules da dama a kan series.
• ​Function:​​ Ya ƙarfi output voltage da string don in iya taimaka da input voltage range da downstream DC/DC boost converter.
3. ​System:​​
• ​Composition:​​ An haɗa da series strings da dama a kan parallel, don in iya taimaka da common DC bus a kan DC/DC converter.
• ​Function:​​ DC bus ya iya taimaka da DC loads ko, a kan DC/AC inverter, ya iya taimaka da AC loads.

​2.2 Core Advantages​
Wannan topology, a kan individual cell-level independent control, ya ƙarfi dabara saboda shading effects da battery balancing issues da ke cikin tushen traditional series structures. Daga baya, a kan proper component selection, tushen ya iya taimaka da PV cells don in iya yi aiki a Maximum Power Point (MPP) da kyau, wanda ya ƙarfi need for additional MPPT circuits da complex Battery Management Systems (BMS).

​III. Hierarchical Monitoring Strategy​

Wannan tushen ya bayar da hierarchical control strategy don in iya taimaka da refined monitoring daga local zuwa global levels.

​3.1 Module-Level Monitoring Strategy (Autonomous Control)​​
Kowane module ya iya kawo ci gaban 5 operating modes da dama based on its own status (PV output voltage, battery voltage):

​3.2 String-Level Monitoring Strategy (Voltage Coordination Control)​​
String-level monitoring uses the DC/DC converter's input voltage (U_in) as the key parameter, stabilizing voltage by connecting/disconnecting modules.

• ​Control Objective:​​ Ensure U_in remains within the DC/DC circuit's allowable operating range (e.g., 12V ~ 22V).
• ​Threshold Control Logic (e.g., for 24V system):​​
• ​Low Voltage Threshold (16V):​​ If U_in < 16V, the monitoring system automatically searches for modules within the string that are in standby mode but have normal battery charge, commanding them to connect, preventing the DC/DC from shutting down due to low input voltage.
• ​High Voltage Threshold (20V):​​ If U_in > 20V, the connection of new modules is restricted to ensure U_in does not exceed the DC/DC's maximum input voltage.
• ​Protection Threshold (12V):​​ If U_in < 12V, the string is deemed depleted, forcibly disconnecting it. All modules enter standby mode until a sufficient number of batteries recover charge.

​3.3 System-Level Monitoring Strategy (Global Protection)​​
System-level monitoring focuses on ensuring power supply quality, with the DC bus voltage (U_bus) as the key monitoring point.

• ​Control Logic:​​ The DC bus voltage is monitored in real-time. If the voltage falls below a critical threshold (e.g., 80% of 24V system rating, i.e., 22V), it indicates insufficient total system energy. The monitoring system will execute a global shutdown command to protect the inverter and load equipment, ensuring AC-side power quality.

​IV. Key Component Selection Method​

To address the matching problem between PV cells and storage batteries, this solution proposes a selection method aimed at maximizing solar energy utilization efficiency.

• ​Core Idea:​​ In this system, the operating voltage of the PV cell is clamped by the battery voltage, making the matching of their voltage parameters critical.
• ​Selection Model:​​ Based on an engineering mathematical model of the PV cell (considering temperature and irradiance effects), the system efficiency η is derived as a function of the battery voltage U_BAT and the PV cell's maximum power point voltage U_mp.
• ​Conclusion:​​ For a 3.7V storage battery with an operating voltage around 3.9V~4.0V, simulation results indicate that the system's solar energy utilization efficiency is highest when the PV cell's U_mp is approximately 4.25V. Therefore, in practical selection, the PV cell's U_mp should be controlled within the range of 4.2V ~ 4.3V.

​V. Expected Outcomes​

1. ​Significant Efficiency Improvement:​​ Modular independent operation completely eliminates the inherent "bucket-brigade effect" and hot-spot issues of series structures, ensuring each unit operates efficiently. Simultaneously, precise voltage matching between PV and storage enables approximate Maximum Power Point Tracking (MPPT) without additional circuits, greatly enhancing power generation efficiency.
2. ​Enhanced Lifespan and Reliability:​​ The modular structure fundamentally resolves the balancing challenges caused by battery pack inconsistencies, avoiding overcharging and over-discharging, effectively extending the overall system lifespan. The hierarchical monitoring strategy provides multiple layers of protection from local to global levels, significantly improving system robustness.
3. ​Cost Optimization and Convenient O&M:​​ This design successfully eliminates the need for complex MPPT trackers and Battery Management Systems (BMS), reducing hardware costs. Its "Lego-like" architecture makes installation, maintenance, and expansion extremely convenient. Failure of a single module does not affect overall operation, reducing the total lifecycle cost.