CN205544949U - Quasi -resonance flyback converter and grid -connected inverter - Google Patents

Abstract

The utility model discloses a quasi -resonance flyback converter and grid -connected inverter, the converter comprises resonant capacitor, power switch, power transformer and rectifier diode to be equipped with the positive output terminal and burden output terminal that are used for connecting positive input terminal and the negative entry terminal of input voltage source follower end and are used for connecting output voltage source input, positive input terminal loops through power transformer's primary side winding and power switch connection negative entry terminal, negative entry terminal ground connection, resonant capacitor is parallelly connected with power transformer's primary side winding, positive output terminal loops through rectifier diode and power transformer's vice limit winding and connects burden output terminal, wherein, positive input terminal is connected to power transformer's primary side winding end of the same name, rectifier diode's positive pole is connected to vice limit winding synonym end, the PWM signal that external equipment sent is received to the control end of power switch. The utility model has the advantages of electrical energy conversion is efficient.

Description

Emmitter diven quasi and combining inverter

Technical field

This utility model relates to a kind of Emmitter diven quasi, and applies the grid-connected inverse of this Emmitter diven quasi Become device.

Background technology

Along with solar energy power generating utilizes the development of form, the power output of component-level optimizes and power conversion more comes More paid attention to, the direct current energy of assembly both can be converted into AC energy and sent into electrical network, it is also possible to be converted into controlled straight Stream electric energy is to battery charging or unified after being collected by dc bus generates electricity by way of merging two or more grid systems.The feature of this series products is input voltage Low, conversion efficiency is high, in the range of power grade is typically in 200-300W.The simple in construction of circuit of reversed excitation topology, is to fit very much Close one of circuit structure of this kind of application.The utility model proposes a kind of quasi-resonance no-voltage open circuit of reversed excitation design and Implementation method, has that conversion efficiency is high, switching frequency is relatively fixed the advantage good with Electro Magnetic Compatibility, and this algorithm counts no-voltage Open required resonance time, can accurately control to export the waveform of electric current.

Utility model content

Technical problem to be solved in the utility model is: provides a kind of Emmitter diven quasi, and applies this standard The combining inverter of harmonic anti exciting converter.

Solving above-mentioned technical problem, the technical scheme that this utility model is used is as follows:

A kind of Emmitter diven quasi, transmits to the electric energy of output voltage source for realizing input voltage source, its feature It is: described Emmitter diven quasi is made up of resonant capacitance, power switch, power transformer and commutation diode, and It is provided with the positive input terminal for connecting described input voltage source output terminal and negative input terminal and for connecting described output The positive output terminal of voltage source input and negative output terminal；Described positive input terminal pass sequentially through the former limit of power transformer around Group and described power switch connect described negative input terminal, described negative input terminal ground connection, described resonant capacitance and power transformation The primary side winding of device is in parallel, described positive output terminal pass sequentially through the secondary of described commutation diode and described power transformer around Group connects described negative output terminal, and wherein, the primary side winding Same Name of Ends of described power transformer connects described positive input terminal, pair Limit winding different name end connects the anode of described commutation diode, control that end receives that external equipment sends the of described power switch One pwm signal, the signal period T of described first pwm signal is by magnetization phase time T_on, demagnetization phase time T_offWith resonance rank Section time T_RForm successively, the controlled magnetization phase time T at described first pwm signal of described power switch_onTurn on, described The demagnetization phase time T of the first pwm signal_offWith resonance phases-time T_RTurn off.

A kind of combining inverter, transmits to the electric energy of AC network for realizing input voltage source, it is characterised in that: described Combining inverter include above-mentioned Emmitter diven quasi and inversion unit, and be provided with for connect described AC network One lead-out terminal and the second lead-out terminal；Described inversion unit is made up of first to fourth switching tube, and described quasi-resonance flyback becomes The positive output terminal of parallel operation divides a two-way, a road to pass sequentially through described first switching tube and the 3rd switching tube connects described negative output Terminal, another road pass sequentially through described second switch pipe and the 4th switching tube connects described negative output terminal, described first switch The junction point of pipe and the 3rd switching tube connects described first lead-out terminal, described second switch pipe and the junction point of the 4th switching tube Connect described second lead-out terminal so that described inversion unit and AC network are relative to described Emmitter diven quasi Described output voltage source；

Each switching tube in described first to fourth switching tube all receives a road pwm signal, described first switching tube The pwm signal received with the 4th switching tube controls to synchronize to lead at the positive half period of described AC network full sinusoidal wave voltage Logical, negative half-cycle synchronizes to turn off, and the pwm signal that described second switch pipe and the 3rd switching tube are received controls in described exchange The positive half period of electrical network full sinusoidal wave voltage synchronizes shutoff, negative half-cycle synchronizes conducting.

Compared with prior art, this utility model has the advantages that

First, Emmitter diven quasi of the present utility model is operated in quasi-resonant mode, has energy conversion efficiency high Advantage.

Second, combining inverter of the present utility model is made up of Emmitter diven quasi and inversion unit, has electric energy The advantage that conversion efficiency is high, it is possible to realize the high efficiency power conversion of solar grid-connected generating, can be used for photovoltaic module, electric power storage The energy of pond group generates electricity by way of merging two or more grid systems.

Accompanying drawing explanation

The utility model is described in further detail with specific embodiment below in conjunction with the accompanying drawings:

Fig. 1 is the circuit theory diagrams of Emmitter diven quasi of the present utility model；

Fig. 2-1 is oscillogram during Emmitter diven quasi of the present utility model work；

Fig. 2-2 is Fig. 2-1 Central Plains, the enlarged diagram of secondary current waveform；

Fig. 3 is the circuit theory diagrams of combining inverter of the present utility model.

Detailed description of the invention

As it is shown in figure 1, Emmitter diven quasi of the present utility model, it is used for realizing input voltage source Uin to output electricity The electric energy transmission of potential source Uout, this Emmitter diven quasi is by resonant capacitance Cp, power switch Sm, power transformer T1 and whole Stream diode D1 composition, and it is provided with positive input terminal J1 for connecting input voltage source Uin outfan and negative input terminal J2 And for connecting positive output terminal J3 and the negative output terminal J4 of output voltage source Uout input；Positive input terminal J1 is successively Primary side winding and power switch Sm by power transformer T1 connect negative input terminal J2, negative input terminal J2 ground connection, resonance Electric capacity Cp is in parallel with the primary side winding of power transformer T1, and positive output terminal J3 passes sequentially through commutation diode D1 and power transformation The vice-side winding of device T1 connects negative output terminal J4, and wherein, the primary side winding Same Name of Ends of power transformer T1 connects positive input terminal Sub-J1, vice-side winding different name end connect the anode of commutation diode D1, and the control end of power switch Sm receives external equipment and sends The first pwm signal, the signal period T of the first pwm signal is by magnetization phase time T_on, demagnetization phase time T_offWith resonance rank Section time T_RForm successively, the controlled magnetization phase time T at the first pwm signal of power switch Sm_onTurn on, believe at a PWM Number demagnetization phase time T_offWith resonance phases-time T_RTurn off.

Working method and the principle of Emmitter diven quasi of the present utility model are as follows:

Emmitter diven quasi of the present utility model has by resonant capacitance Cp, power switch Sm, power transformer T1 With the anti exciting converter circuit structure topology of commutation diode D1 composition, it is operated in quasi-resonant mode, it may be assumed that

Seeing Fig. 2-1 and Fig. 2-2, Emmitter diven quasi of the present utility model is at a signal of the first pwm signal Operation mode in cycle T is divided into three phases:

From t₀Moment is to t₁The magnetization phase in moment: time a length of magnetization phase time T_on, power switch Sm leads during this period Logical, A point electromotive force is zero, the voltage V of input voltage source Uin_inIt is added in the former limit of transformator T1, the former limit exciting current of transformator T1 Linearly increasing, energy is stored in the primary side winding of power transformer T1.

From t₁Moment is to t₂The demagnetization phase in moment: time a length of demagnetization phase time T_off, power switch Sm is at t₁Moment by ON transitions is for turning off, and now the primary current of power transformer T1 reaches maximum i_{p_peak}, and power switch Sm turns off After, the commutation diode D1 conducting of secondary, output voltage V_outReflexing to former limit, amplitude is V_out/ N, A point electromotive force increases to (V_in+ V_out/ N), the energy that the primary side winding of power transformer T1 stores transfers to secondary loop, t₁Moment secondary current i_sMaximum For i_{s_peak}.Along with secondary current i_sBeing reduced to zero, secondary commutation diode D1 turns off naturally.

From t₂Moment is to t₃The resonant stage in moment: time a length of resonant stage time T_R, t₂Moment, resonant capacitance Cp and merit The resonant network that the primary side winding of rate switch Sm is formed starts resonance, and A point electromotive force is gradually lowered, until t₃Moment, along with merit Rate switch Sm's is open-minded, and resonant stage terminates, and the newest signal period T starts.

Therefore, Emmitter diven quasi of the present utility model has the advantage that energy conversion efficiency is high.

It addition, the first pwm signal that the external equipment obtained in the following manner sends, it is possible to make of the present utility model Emmitter diven quasi obtains more excellent technique effect, is described in detail below:

The signal period T=T of the first pwm signal_on+T_off+T_RWith dutycycle d=T_on/ T is by input voltage source Uin voltage With the sampling period change that output voltage source Uout voltage carries out synchronized sampling, the first pwm signal is in each sampling period Signal period T, magnetization phase time T_on, demagnetization phase time T_offWith resonance phases-time T_R=nT_rBy below equation [1] it is calculated to formula [6] simultaneous solution:

$T_r=\frac{1}{2\mathrm{\π}\sqrt{L_p*C}}---\[1\]$

i_{p_peak}=N*i_{s_peak} [2]

$T_{on}=\frac{L_p}{V_{in}}*i_{p\_peak}---\[3\]$

$T_{off}=\frac{N^2{L}_p}{V_{out}}*i_{s\_peak}---\[4\]$

$I_{o\_avg}=\frac{\frac{1}{2}*i_{s\_peak}*T_{off}}{T_{on}+T_{off}+T_r}---\[5\]$

$I_{p\_peak}=\frac{I_{o\_avg}*({\mathrm{NL}}_p+L_p{V}_{out}/V_{in})+V_{out}\sqrt{I_{o\_avg}^2{({\mathrm{NL}}_p/V_{out}+L_p/V_{in})}^2+2{\mathrm{nL}}_p{T}_r/V_{out}}}{L_p}---\[6\]$

In formula, V_inAnd V_outBeing respectively sampled in the start time of the i.e. current sample period of current voltage sampling instant obtains The voltage of input voltage source Uin and the voltage of output voltage source Uout, T_rFor described resonant capacitance Cp and power switch Sm's The harmonic period of the formed resonant network of primary side winding, n is at resonant stage time T_RThe harmonic period of interior described resonant network Number preset value, C is resonant capacitance C_pCapacitance, L_p, N=N_s/N_p、N_SAnd N_pIt is respectively the former limit excitation electricity of power transformer T1 Sense, the turn ratio, the secondary number of turn and the former limit number of turn, i_{p_peak}And i_{s_peak}Represent primary current peak value and the pair of power transformer T1 respectively Limit current peak, I_{o_avg}Represent the output average current i.e. average current of commutation diode D1 of changer.

Principle that above-mentioned first pwm signal is controlled by utility model and to can be obtained with effect as follows:

The utility model signal period T=T to above-mentioned first pwm signal_on+T_off+T_RWith dutycycle d=T_on/ T carries out week Phase property controls, it may be assumed that at each, input voltage source Uin voltage and output voltage source Uout voltage are carried out the sampling of synchronized sampling In the cycle, all calculate the first pwm signal to should the signal period T in sampling period and dutycycle according to formula [1] to formula [6] D so that the signal period T calculated and dutycycle d are controlled by harmonic period number preset value n and time the corresponding sampling period starts Carve the voltage V of the input voltage source Uin that sampling obtains_in, the voltage V of output voltage source Uout_out, thus in each sampling period The switch motion of interior accurate power control switch Sm, to reach techniques below effect:

First, it is achieved modulation and the shaping to Emmitter diven quasi output current wave, i.e. make this output electric current The phase place of waveform follows the sampled voltage V of output voltage source Uout_outPhase synchronization change, amplitude follow input voltage source Uin's Sampled voltage V_inAmplitude synchronizes change, and makes power switch Sm be operated in no-voltage or trough opens pattern (i.e. at each The finish time of signal period T, power switch Sm is at the A point potential drop as little as resonant stage voltage wave of the i.e. Fig. 1 of its drain-source voltage Transferred to conducting state by off state during paddy) and commutation diode D1 naturally turn off, reach: to output voltage source the most simultaneously Uout provides the effect of high-quality supply current, controls the Emmitter diven quasi output average current in each sampling period Or output size is to realize the effect of the mode of operation such as constant current or invariable power, and, the switch reducing power switch Sm damages Consume to improve the effect of Emmitter diven quasi energy conversion efficiency.

Above-mentioned technique effect, Emmitter diven quasi of the present utility model is utilized to can act as miniature grid type inversion The products such as device, power optimization controller, charge controller, solar charging controller, output voltage source Uout can be used as voltage Source or controlled voltage source, the energy size transmitted in controlling each switch periods by control primary side current of transformer, it is achieved The mode of operation such as invariable power, constant current, meets power optimization and the needs of charging control.

Second, for Emmitter diven quasi in different application scenarios, by rationally arranging harmonic period number The value of preset value n, can control power switch Sm and be allowed to open-minded at the n-th trough of its drain-source voltage, i.e. control letter The length of number cycle T, so that power switch Sm all can be operated in conjunction under the conditions of different input voltages and output Under suitable switching frequency, improve the work efficiency of power switch Sm, to guarantee that Emmitter diven quasi can be different defeated Higher energy conversion efficiency it is respectively provided with, to solve " quasi-resonance flyback of the present utility model under the conditions of entering voltage and output Changer is too high at input voltage, output voltage is too low and export electric current less in the case of, the switching frequency of power switch Sm Will become the highest and affect its work efficiency " problem.

Wherein, when Emmitter diven quasi of the present utility model is as Miniature inverter:

Sampled voltage V at input voltage source Uin_inOutput at 28V to 48V and Emmitter diven quasi is During 250W, harmonic period number preset value n value is 1, and now the switching frequency of power switch Sm is between 103k to 161.8k；

Sampled voltage V at input voltage source Uin_inOutput at 33V to 44V and Emmitter diven quasi is During 140W, harmonic period number preset value n value is 2, and now the switching frequency of power switch Sm is between 132k to 154.1k；

Sampled voltage V at input voltage source Uin_inOutput at 22V to 33V and Emmitter diven quasi is During 100W, harmonic period number preset value n value is 2, now the switching frequency of power switch Sm 118.8k to 154.5k it Between；

Sampled voltage V at input voltage source Uin_inOutput at 33V to 44V and Emmitter diven quasi is During 70W, harmonic period number preset value n value is 3, and now the switching frequency of power switch Sm is between 123k to 131.9k；

Sampled voltage V at input voltage source Uin_inOutput at 22V to 33V and Emmitter diven quasi is During 50W, harmonic period number preset value n value is 3, and now the switching frequency of power switch Sm is between 117k to 132k；

Sampled voltage V at input voltage source Uin_inOutput at 15V to 56V and Emmitter diven quasi is During 20W, harmonic period number preset value n value is 4, and now the switching frequency of power switch Sm is between 98.3k to 111.2k.

From above-mentioned data, when Emmitter diven quasi of the present utility model is used as Miniature inverter, by above-mentioned bar Part arranges the value of harmonic period number preset value n, effectively the switching frequency of power switch Sm can be limited in 200k Hz Below.

As it is shown on figure 3, combining inverter of the present utility model, for realizing input voltage source Uin to AC network Ug's Electric energy transmits, and this combining inverter includes above-mentioned Emmitter diven quasi and inversion unit, and is provided with for connecting alternating current The first lead-out terminal J5 and the second lead-out terminal J6 of net Ug；Inversion unit is made up of first to fourth switching tube S1～S4, accurate Positive output terminal J3 of harmonic anti exciting converter divides a two-way, a road to pass sequentially through the first switching tube S1 and the 3rd switching tube S3 even Meet negative output terminal J4, another road passes sequentially through second switch pipe S2 and the 4th switching tube S4 connection negative output terminal J4, and first The junction point of switching tube S1 and the 3rd switching tube S3 connects the first lead-out terminal J5, second switch pipe S2 and the 4th switching tube S4 Junction point connect the second lead-out terminal J6 so that inversion unit and AC network Ug are relative to Emmitter diven quasi Output voltage source Uout.

Each switching tube in first to fourth switching tube S1～S4 all receives a road pwm signal, the first switching tube S1 The pwm signal received with the 4th switching tube S4 controls to synchronize to lead at the positive half period of AC network Ug full sinusoidal wave voltage Logical, negative half-cycle synchronizes to turn off, and the pwm signal that second switch pipe S2 and the 3rd switching tube S3 is received controls at AC network The positive half period of Ug full sinusoidal wave voltage synchronizes shutoff, negative half-cycle synchronizes conducting so that: at the meter of formula [1] to formula [6] In calculation, V_out=| V_g|,V_gFor the alternating current obtained in the sampling of the start time of current voltage sampling instant i.e. current sample period The voltage of net Ug.

Combining inverter of the present utility model utilizes above-mentioned Emmitter diven quasi to be capable of solar grid-connected generating High efficiency power conversion, can be used for generating electricity by way of merging two or more grid systems the energy of photovoltaic module, accumulator battery.

This utility model is not limited to above-mentioned detailed description of the invention, according to foregoing, according to the ordinary skill of this area Knowledge and customary means, without departing under this utility model above-mentioned basic fundamental thought premise, this utility model can also be made The equivalent modifications of other various ways, replace or change, all fall among protection domain of the present utility model.

Claims (2)

1. an Emmitter diven quasi, is used for realizing input voltage source (Uin) and passes to the electric energy of output voltage source (Uout) It is defeated, it is characterised in that: described Emmitter diven quasi is by resonant capacitance (Cp), power switch (Sm), power transformer (T1) form with commutation diode (D1), and be provided with the positive input terminal for connecting described input voltage source (Uin) outfan (J1) and negative input terminal (J2) and being used for connect the positive output terminal (J3) of described output voltage source (Uout) input and Negative output terminal (J4)；Described positive input terminal (J1) passes sequentially through the primary side winding of power transformer (T1) and described power is opened Closing (Sm) and connect described negative input terminal (J2), described negative input terminal (J2) ground connection, described resonant capacitance (Cp) becomes with power The primary side winding of depressor (T1) is in parallel, and described positive output terminal (J3) passes sequentially through described commutation diode (D1) and described power The vice-side winding of transformator (T1) connects described negative output terminal (J4), wherein, the primary side winding of described power transformer (T1) Same Name of Ends connects described positive input terminal (J1), the anode of the vice-side winding different name end described commutation diode of connection (D1), described The end that controls of power switch (Sm) receives the first pwm signal that external equipment sends, the signal period T of described first pwm signal By magnetization phase time T_on, demagnetization phase time T_offWith resonance phases-time T_RForming successively, described power switch (Sm) is controlled Magnetization phase time T at described first pwm signal_onConducting, at the demagnetization phase time T of described first pwm signal_offHarmonious Shake phases-time T_RTurn off.

2. a combining inverter, is used for realizing input voltage source (Uin) and transmits to the electric energy of AC network (Ug), and its feature exists In: described combining inverter includes the Emmitter diven quasi described in claim 1 and inversion unit, and is provided with for even Connect the first lead-out terminal (J5) and second lead-out terminal (J6) of described AC network (Ug)；Described inversion unit is by first to Four switching tubes (S1～S4) form, and the positive output terminal (J3) of described Emmitter diven quasi point position two-way, a road leads to successively Cross described first switching tube (S1) and the 3rd switching tube (S3) connects described negative output terminal (J4), another road passes sequentially through described Second switch pipe (S2) and the 4th switching tube (S4) connect described negative output terminal (J4), described first switching tube (S1) and the 3rd The junction point of switching tube (S3) connects described first lead-out terminal (J5), described second switch pipe (S2) and the 4th switching tube (S4) Junction point connect described second lead-out terminal (J6) so that described inversion unit and AC network (Ug) are humorous relative to described standard The anti exciting converter that shakes is described output voltage source (Uout)；

Each switching tube in described first to fourth switching tube (S1～S4) all receives a road pwm signal, and described first opens The pwm signal that pass pipe (S1) and the 4th switching tube (S4) are received controls at described AC network (Ug) full sinusoidal wave voltage Positive half period synchronizes conducting, negative half-cycle synchronizes to turn off, and described second switch pipe (S2) and the 3rd switching tube (S3) are received Pwm signal control described AC network (Ug) full sinusoidal wave voltage positive half period synchronize turn off, negative half-cycle synchronize lead Logical.