鋰離子電池的現代儲能系統(tǒng)由于其高效和可靠的性能，在各類應用中得到了廣泛的采用。然而，確保系統(tǒng)的安全性和穩(wěn)定性需要對每個電池單元進行嚴格監(jiān)控，以防止電池的不平衡、過度充電、深度放電或過熱現象。實現這一目標需要為每個電池單元或電池陣列提供獨立的隔離電源電壓控制電路。

對于標稱電壓高達48V的電池陣列，通常可以使用提供500V或1600V隔離屏障的標準工業(yè)DC/DC電源轉換器模塊。然而，對于那些需要更高功率并連接到交流電源的系統(tǒng)，電池陣列電壓可能達到600-800V，這就需要具有更高隔離屏障的解決方案。

低隔離電容增強抗噪能力

P-DUKE的醫(yī)療電源轉換器系列具有5kV隔離屏障，超過了常規(guī)4kV的需求。在該項目中，選擇了MPD30-24S12，它可以從公共24V直流總線產生必要的12V/30W電源電壓。

典型的工業(yè)30W DC/DC電源轉換器的輸入輸出電容可達1500pF。如果并聯使用多達200個轉換器，電池單元（通過充電器連接到交流電網）和24V總線之間的總電容可能達到300nF，導致交流漏電流超過20mA。超過10mA的電流可能導致嚴重的觸電和事故。

MPD30-24S12的輸入輸出電容僅20pF，因此200個轉換器并聯后的總電容僅為4nF，漏電流小于1mA。這樣的低電容也避免了瞬態(tài)或任何噪聲從交流/電池側跨轉換器耦合到中央電池管理系統(tǒng)的敏感通訊信號。

通過這一解決方案，4kV隔離和低漏電流要求得到了很好的滿足。

通信和電源解決方案

對于整個安裝中的通信，中央BMS控制器使用Wifi路由器，通過以太網由25W的53V電源供電。根據安裝，電源電壓可以由230Vac主電源或內部24Vdc總線產生。對于230Vac，可以使用TSD30系列轉換器。它還提供Din導軌式版本，便于安裝在控制器機架中。

成功案例表明，通過RCD30系列轉換器可以從24Vdc總線產生53V電壓，并將輸出從54V調整至53V。它還配有集成散熱器，易于冷卻。

P-DUKE產品應用

MPD30/MPD30W系列是一系列30W DC/DC電源轉換器，具有增強型5000Vac隔離電壓，符合醫(yī)療應用的要求。該系列具有不同的輸入電壓范圍，并提供單路或雙路輸出。該系列符合2MOPP標準，電氣間隙和爬電距離為8毫米。這使得它們不僅適用于醫(yī)療設備，也適用于其他需要高隔離度和極低輸入輸出電容的應用。

TSD30系列是一款適用于Din導軌式應用的即用型交流/直流解決方案。與RCD30W系列一樣，它為各種應用提供不同的輸出電壓和安裝選項。

 

The modern energy storage system of lithium-ion batteries has been widely adopted in various applications due to its efficient and reliable performance. However, ensuring the safety and stability of the system requires strict monitoring of each battery unit to prevent battery imbalance, overcharging, deep discharge, or overheating. To achieve this goal, it is necessary to provide independent isolated power supply voltage control circuits for each battery unit or battery array.
For battery arrays with a nominal voltage of up to 48V, standard industrial DC/DC power converter modules that provide 500V or 1600V isolation barriers can usually be used. However, for systems that require higher power and are connected to AC power sources, the battery array voltage may reach 600-800V, which requires solutions with higher isolation barriers.
Low isolation capacitance enhances noise resistance
The P-DUKE medical power converter series has a 5kV isolation barrier, exceeding the conventional requirement of 4kV. In this project, MPD30-24S12 was selected, which can generate the necessary 12V/30W power voltage from the common 24V DC bus.
The input and output capacitance of a typical industrial 30W DC/DC power converter can reach 1500pF. If up to 200 converters are used in parallel, the total capacitance between the battery unit (connected to the AC grid through a charger) and the 24V bus may reach 300nF, resulting in an AC leakage current exceeding 20mA. A current exceeding 10mA may cause serious electric shock and accidents.
The input and output capacitance of MPD30-24S12 is only 20pF, so the total capacitance after 200 converters are connected in parallel is only 4nF, and the leakage current is less than 1mA. This low capacitance also avoids transient or any noise coupling from the AC/battery side converter to the sensitive communication signal of the central battery management system.
Through this solution, the requirements for 4kV isolation and low leakage current have been well met.
Communication and Power Solutions
For communication throughout the installation, the central BMS controller uses a WiFi router and is powered by a 25W 53V power supply via Ethernet. According to the final installation, the power supply voltage can be generated by a 230Vac main power supply or an internal 24Vdc bus. For 230Vac, TSD30 series converters can be used. It also offers a Din rail version for easy installation in the controller rack.
Successful cases have shown that the RCD30 series converter can generate a 53V voltage from the 24Vdc bus and adjust the output from 54V to 53V. It also comes with an integrated heat sink for easy cooling.
P-DUKE product application
The MPD30/MPD30W series is a series of 30W DC/DC power converters with enhanced 5000Vac isolation voltage, which meets the requirements of medical applications. This series has different input voltage ranges and provides single or dual output. This series complies with the 2MOPP standard, with an electrical clearance and creepage distance of 8 millimeters. This makes them suitable not only for medical devices, but also for other applications that require high isolation and extremely low input/output capacitance.
The TSD30 series is a ready to use AC/DC solution suitable for Din rail applications. Like the RCD30W series, it provides different output voltages and installation options for various applications.