Pv power converter

Abstract

It provides a PV power converter (2) including: a transformer (23), a first output port (Pout1) and a second output port (Pout2), a first power conversion circuit (24) being configured to convert power from PV array (20) into AC power. The first power conversion circuit (24) has a first input terminal (Tin1) and a second input terminal (Tin2) being configured to be electrically coupled to outputs of PV array (20) with the second input terminal (Tin2) electrically coupled to the second output port (Pout2); and a first output terminal (Tout1) and a second output terminal (Tout2) electrically coupled to a primary winding (23p) of the transformer (23). The PV power converter (2) also includes a second power conversion circuit (25) being configured to convert power from the transformer (23) into DC power. The second power conversion circuit (25) has a first input end (E in1) and a second input end (E in2) electrically coupled to a secondary winding (23s) of the transformer (23), and a first output end (E out1) electrically coupled to the first output port (P out1) and a second output end (Eout2 ) electrically coupled to the first input terminal (Tin1) of the first power conversion circuit (24). The PV power converter (2) also includes a first power switch (Q 1) being arranged electrically between either of the first input terminal (Tin1) and the second input terminal (Tin2) and either of the first output port (Pout1) and the second output port (Pout2), having a conducting direction allowing unidirectional current flow.

Description

technical field [0001] The present invention relates generally to PV (photovoltaic) power conversion, and more particularly to protection against faults in PV power conversion equipment. Background technique [0002] Photovoltaic systems are very popular as a renewable energy source in many applications. PV modules of photovoltaic systems have a maximum power point (MPP) phenomenon, ie a PV module outputs maximum power at a certain point that is not the end of the operating range. In addition, the output power of PV modules will vary with temperature and irradiance. Figure 1A is the P-V curve of the PV module showing the MPP phenomenon. Such as Figure 1A As shown, in region A, in the direction towards the MPP, the output power of the PV module increases with the increase of the output voltage of the PV module. On the contrary, in the region B, in the direction away from the MPP, the output power of the PV module decreases with the increase of the output voltage of the PV...

AI Technical Summary

Problems solved by technology

[0006] Although PPC provides high system efficiency, it has disadvantages during input DC bus short-circuit fault: when input DC bus short-circuit fault occurs, such as Figure 2A shown, the rectifier will have to withstand the voltage V out , that is, V c =V out , where V c is the voltage at the rectifier

Although the fault current injected from the DC input side (PV panel) is not high, it hinders the arc extinguishing of the DC fault current, which may cause additional damage to the cable insulation of the output DC bus

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