基于SPV1020設(shè)計(jì)的太陽能電池DC-DC電源轉(zhuǎn)換方案

SPV1020是ST 公司的內(nèi)置了MPPT算法的PWM模式DC/DC升壓轉(zhuǎn)換器，能最大化太陽能電池板所產(chǎn)生的能量，不受溫度和太陽輻射的影響。MPPT算法精度在0.2%，工作電壓0-36V，具有過壓，過流和超溫保護(hù)，內(nèi)置了軟起動(dòng)，效率高達(dá)98%。本文介紹了SPV1020主要特性，方框圖和應(yīng)用電路。

Interleaved DC-DC boost converter with built-in MPPT algorithm SPV1020 is a monolithic DC-DC boost converter designed to maximize the power generated by photovoltaic panels independently of temperature and amount of solar radiation.

The optimization of the power conversion is obtained with an embedded logic which performs the MPPT (max power point tracking) algorithm on the PV cells connected to the converter.

One or more converters can be housed in the connection box of PV panels, replacing the bypass diodes, and thanks to the fact that the maximum power point is locally computed, the efficiency at system level will be higher than the one of conventional topologies, where the MPP is computed in the main centralized inverter.

For a cost effective application solution and miniaturization needs, SPV1020 embeds the power MOSFETs for active switches and synchronous rectification, minimizing the number of external devices. Furthermore, the 4 phase interleaved topology of the DC-DC converter allows to avoid the use electrolytic capacitors, which would severely limit the lifetime.

It works at fixed frequency in PWM mode, where the duty cycle is controlled by the embedded logic running a PerturbObserve MPPT algorithm. The switching frequency, internally generated and set by default at 100 kHz, is externally tunable, while the duty cycle can range from 5% to 90% with a step of 0.2%.

Safety of the application is guaranteed by stopping the drivers in case of output over-voltage or overtemperature.

SPV1020主要特性：

■ PWM mode DC-DC boost converter

■ Duty cycle controlled by MPPT ALGORITHM with 0.2% accuracy

■ Operating voltage range 0-36 V

■ Overvoltage, overcurrent, overtemperature protections

■ Built in soft-start

■ Up to 98% efficiency

■ Automatic transition to burst mode for improved efficiency at low solar radiation

■ SPI interface

SPV1020應(yīng)用：

■ Photovoltaic panels

圖1。SPV1020簡化方框圖

圖2。SPV1020應(yīng)用電路