CN202535290U

CN202535290U - Photovoltaic inverter circuit

Info

Publication number: CN202535290U
Application number: CN 201220138870
Authority: CN
Inventors: 张运权
Original assignee: SUZHOU UNIVERSAL-POWER Co Ltd
Current assignee: SUZHOU UNIVERSAL-POWER Co Ltd
Priority date: 2012-04-05
Filing date: 2012-04-05
Publication date: 2012-11-14
Anticipated expiration: 2022-04-05

Abstract

The utility model discloses a photovoltaic inverter circuit. The photovoltaic inverter circuit comprises a control circuit, a direct-current power supply parallel circuit at the input end and an alternating current network parallel circuit at the output end. The photovoltaic inverter circuit is characterized in that the direct-current power supply parallel circuit at the input end comprises two parallel branches; the connection sequence of the first branch is: a power supply positive end, a first switch tube S1, a second switch tube S2, a third switch tube S3 and a power supply negative end; the connection sequence of the second branch is: the power supply positive end, a fourth switch tube S4, a fifth switch tube S5, a sixth switch tube S6 and the power supply negative end; the alternating current network parallel circuit comprises two parallel branches; the connection sequence of the first branch is: a first filter inductor L1, an alternating current network, a second filter inductor L2, a first diode D1, the second switch tube S2; the connection sequence of the second branch is: the first filter inductor L1, the alternating current network, the second filter inductor L2, a second diode D2, the fifth switch tube S5; a capacitor C1 is provided between the power supply positive end and the power supply negative end; a capacitor C2 is provided between the first filter inductor L1, the second filter inductor L2 and an alternating current network connection end. According to the utility model, six switch tubes are provided, thus the conversion efficiency is high; and when a high frequency switch tube is turned off, follow current is produced through the diodes, thus current leakage of an inverter is effectively suppressed.

Description

A kind of photovoltaic inverter circuit

Technical field

the utility model belongs to field of photovoltaic power generation, is specifically related to a kind of photovoltaic inverter circuit.

Background technology

In order to realize the sustainable development of society, the development and utilization of regenerative resource is just more and more paid attention to by the mankind .As one of pollution-free green energy, solar energy strides forward to basic energy resource from alternative energy source just gradually.Parallel network power generation will be developed as the principal mode of solar energy photovoltaic utilization rapidly.Photovoltaic DC-to-AC converter is a kind of electric power adjusting device of being made up of semiconductor device, is mainly used in and converts direct current power to alternating electromotive force.Generally constitute by boost loop and inversion bridge type return.The loop of boosting boosts to the required direct voltage of inverter output control to the direct voltage of solar cell; The inversion bridge type return then converts the direct voltage after boosting to the alternating voltage of conventional frequency of equal valuely.It is not high that existing photovoltaic 4 pipe full-bridge inverting inverters change efficient, can not the good restraining leakage current.

Summary of the invention

the utility model purpose is: provide a kind of and can suppress leakage current, the higher photovoltaic inverter circuit of variation efficient.

The technical scheme of the utility model is: a kind of photovoltaic inverter circuit, comprise control circuit, the DC power supply parallel circuits of input and output with the AC network parallel circuits, it is characterized in that:

The DC power supply parallel circuits of said input comprises two parallel branches, and the order that article one branch road connects is: power positive end, the first switching tube S1, second switch pipe S2, the 3rd switching tube S3, power supply negative terminal; The order that the second branch road connects is: power positive end, the 4th switching tube S4, the 5th switching tube S5, the 6th switching tube S6, power supply negative terminal;

Said AC network parallel circuits comprises two parallel branches, and the order of the connection of article one branch road is: the first filter inductance L1, AC network, the second filter inductance L2, the first diode D1, second switch pipe S2; The order that the second branch road connects is: the first filter inductance L1, AC network, the second filter inductance L2, the second diode D2, the 5th switching tube S5;

Between said power positive end and the power supply negative terminal capacitor C 1 is arranged, be provided with capacitor C 2 between the said first filter inductance L1, the second filter inductance L2 and the AC network link.

are further, and the first switching tube S1, second switch pipe S2, the 3rd switching tube S3, the 4th switching tube S4, the 5th switching tube S5, the 6th switching tube S6 are N raceway groove insulated gate bipolar transistor.

are further, and two low frequencies of said control circuit drive and are 50Hz.

The utility model has the advantages that:

six switching tubes, transformation efficiency is higher, when the HF switch pipe turn-offs, through diode continuousing flow, has effectively suppressed the leakage current of inverter.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

Fig. 1 is the photovoltaic inverter circuit circuit diagram of the utility model.

Embodiment

embodiment: photovoltaic inverter circuit as shown in Figure 1, C1 are that bus capacitor, S1 ~ S6 are 6 IGBT switching tubes, D1, and D2 is fly-wheel diode, L1, and L2 is that output inductor, C2 are that output filter capacitor, AC are civil power.SPW1 ~ SPWM4 drive signal is produced by control circuit.Photovoltaic inverter circuit in the present embodiment; Comprise control circuit; The DC power supply parallel circuits of input and output with the AC network parallel circuits; The DC power supply parallel circuits of input comprises two parallel branches, and the order that article one branch road connects is: power positive end, switching tube S1, switching tube S2, switching tube S3, power supply negative terminal; The order that the second branch road connects is: power positive end, switching tube S4, switching tube S5, switching tube S6, power supply negative terminal; The AC network parallel circuits comprises two parallel branches, and the order of the connection of article one branch road is: filter inductance L1, AC network, filter inductance L2, diode D1, switching tube S2; The order that the second branch road connects is: filter inductance L1, AC network, filter inductance L2, diode D2, switching tube S5; Capacitor C 1 is arranged between power positive end and the power supply negative terminal, be provided with capacitor C 2 between filter inductance L1, filter inductance L2 and the AC network link.Wherein, input is the DC DC power supply, and input two ends capacitor C 1 is a bus capacitor, and six switching tubes of inverter bridge are N raceway groove IGBT pipe.Wherein, control circuit produces two-way high frequency SPWM and drives (being respectively SPWM1, SPWM2) two low frequency 50Hz drivings (being respectively SPWM3, SPWM4).Wherein, output termination AC civil power, LC filtering is taked in output filtering.Adopt the beneficial effect of present technique scheme to be: six switching tubes, transformation efficiency is higher, when the HF switch pipe turn-offs, through diode continuousing flow, has effectively suppressed the leakage current of inverter.

During operating state: 1. positive half cycle, switching tube S2, switching tube S3, switching tube S4 turn-off, switching tube S5 conducting all the time, switching tube S1, switching tube S6 work in high frequency and open off state.The loop that constitutes is: bus, switching tube S1, filter inductance L1, AC civil power, filter inductance L2, switching tube S5, switching tube S6, bus.Wherein switching tube S1, switching tube S6 drive signal all come from the SPWM1 high-frequency signal, and switching tube S5 drive signal comes from SPWM1 low frequency 50Hz signal.As switching tube S1, when switching tube S6 is operated in off state, switching tube S5 conducting this moment is through diode D2 afterflow.The loop that constitutes is: filter inductance L1, AC civil power, filter inductance L2, switching tube S5, diode D1 filter inductance L1.

negative half period, switching tube S1, switching tube S5, switching tube S6 turn-off, and switching tube S2 conducting all the time, switching tube S3, switching tube S4 work in high frequency and open off state.The loop that constitutes is: bus, switching tube S4, filter inductance L2, AC civil power, filter inductance L1, switching tube S2, switching tube S3, bus.Wherein switching tube S3, switching tube S4 drive signal all come from the SPWM1 high-frequency signal, and switching tube S2 drive signal comes from SPWM1 low frequency 50Hz signal.As switching tube S3, when switching tube S4 is operated in off state, switching tube S5 conducting this moment, through diode D2 afterflow, the loop of formation is: filter inductance L2, AC civil power, filter inductance L1, switching tube S5, diode D2, filter inductance L2.

above embodiment is merely the utility model a kind of execution mode wherein, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the utility model claim.Should be pointed out that for the person of ordinary skill of the art under the prerequisite that does not break away from the utility model design, can also make some distortion and improvement, these all belong to the protection range of the utility model.Therefore, the protection range of the utility model patent should be as the criterion with accompanying claims.

Claims

1. a photovoltaic inverter circuit comprises control circuit, the DC power supply parallel circuits of input and output with the AC network parallel circuits, it is characterized in that:

The DC power supply parallel circuits of said input comprises two parallel branches, and the order that article one branch road connects is: power positive end, first switching tube (S1), second switch pipe (S2), the 3rd switching tube (S3), power supply negative terminal; The order that the second branch road connects is: power positive end, the 4th switching tube (S4), the 5th switching tube (S5), the 6th switching tube (S6), power supply negative terminal;

Said AC network parallel circuits comprises two parallel branches, and the order of the connection of article one branch road is: first filter inductance (L1), AC network, second filter inductance (L2), first diode (D1), second switch pipe (S2); The order that the second branch road connects is: first filter inductance (L1), AC network, second filter inductance (L2), second diode (D2), the 5th switching tube (S5);

Electric capacity (C1) is arranged between said power positive end and the power supply negative terminal, be provided with electric capacity (C2) between said first filter inductance (L1), second filter inductance (L2) and the AC network link.

2. photovoltaic inverter circuit according to claim 1 is characterized in that: first switching tube (S1), second switch pipe (S2), the 3rd switching tube (S3), the 4th switching tube (S4), the 5th switching tube (S5), the 6th switching tube (S6) are N raceway groove insulated gate bipolar transistor.

3. photovoltaic inverter circuit according to claim 2 is characterized in that: two low frequencies of said control circuit drive and are 50Hz.