CN107565844B - A kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter - Google Patents
A kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter Download PDFInfo
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- CN107565844B CN107565844B CN201710725022.8A CN201710725022A CN107565844B CN 107565844 B CN107565844 B CN 107565844B CN 201710725022 A CN201710725022 A CN 201710725022A CN 107565844 B CN107565844 B CN 107565844B
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Abstract
A kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter disclosed by the invention, the modulator approach judge current variator operating mode by the product of network voltage and electric current.Voltage pulse of zero module forward or backwards will be inputted by selection switch after the modulating wave progress full-wave rectification of Sinusoidal Pulse Width Modulation.Converter work selects positive voltage pulse of zero module in inverter mode, and converter works in rectification mode, selects reversed voltage pulse of zero module.Modulating wave generates bridgc arm short signal and auxiliary switch signal after inputting voltage pulse of zero module forward or backwards, acts on short-circuit signal on main switch during the converter change of current, magnetizes for resonant inductance and provides continuous current circuit, to provide enough resonant energies.The configuration of the present invention is simple, inversion realize that no-voltage is open-minded with switching devices all in rectification mode, and switching loss is small, and circuit efficiency is high, and can inhibit diode reverse recovery, reduce electromagnetic interference.
Description
Technical field
The present invention relates to the two-way of soft switch transducer and its modulation technique more particularly to a kind of single-phase DC-AC converter
Zero voltage switch modulator approach.
Background technique
Single-phase DC-AC converter is the device that direct current is converted to single-phase alternating current, and common topology is full-bridge topology,
The two-way flow work of energy can be achieved.Circuit works in hard switching state, and there are diode reverse recovery phenomenon, devices switch
Loss is big, limits the raising of working frequency, reduces circuit efficiency and there are electromagnetic interferences.Resonance DC bus Sofe Switch skill
Art is applied to single-phase DC-AC converter, is able to achieve the zero voltage switch of device, reduces switching loss.Positive inverter mode with
And reversed rectification mode, alternating current amplitude is larger with phase change, and common Sinusoidal Pulse Width Modulation method is difficult to realize
Two-way gamut Sofe Switch.
Summary of the invention
The purpose of the present invention is overcome the deficiencies of the prior art and provide a kind of two-way no-voltage of single-phase DC-AC converter
Switch modulating method.
The two-way zero voltage switch modulator approach of single-phase DC-AC converter is to provide positive no-voltage (ZVS) pulse
Module generates auxiliary switch forward direction modulated signal all the way and all the way positive bridgc arm short signal；One reversed no-voltage is provided
(ZVS) pulse module generates auxiliary switch back-modulation signal all the way and all the way reversed bridgc arm short signal；Converter is calculated to hand over
Galvanic electricity current voltage product.When product is positive, positive voltage pulse of zero module is selected, when product is negative, selects reversed no-voltage arteries and veins
Die block.According to the polarity of converter alternating voltage amp product, the positive bridge arm that positive voltage pulse of zero module is exported is short
Four tunnels of the reversed bridgc arm short signal and the output of frequency multiplication SPWM modulation module of road signal or the output of reversed voltage pulse of zero module
Modulated signal carries out logical "or" operation respectively.According to the polarity of converter alternating voltage amp product, positive no-voltage is selected
The auxiliary switch forward direction modulated signal of pulse module output or the auxiliary switch back-modulation of reversed voltage pulse of zero module output
Driving signal of the signal as auxiliary switch.
There are three ports altogether for positive voltage pulse of zero module, and port 1 is modulating wave absolute value input port, and port 2 is just
To bridgc arm short signal output port, port 3 is auxiliary switch forward direction modulated signal output port.Reversed voltage pulse of zero module
There are three ports altogether, and port 1 is modulating wave absolute value input port, and port 2 is reversed bridgc arm short signal output port, port
3 be auxiliary switch back-modulation signal output port.
In a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter, the exchange of single-phase DC-AC converter is defeated
Voltage v outoWith output electric current ioThe first multiplier is inputted after sampled, the output end and first comparator of the first multiplier are just
Input terminal connection, the negative input end of first comparator are 0.The output signal of first comparator alternatively signal, is separately connected
The port 4 of first choice switch, the second selection switch, third selection switch.Modulating wave connects while connecting frequency multiplication SPWM modulation
The input port 5 of module and the input terminal of absolute value block, the port of the output end connection first choice switch of absolute value block
3.The port 1 of first choice switch is connect with the input port 1 of positive voltage pulse of zero module, the port 2 of first choice switch
It is connect with the input port 1 of reversed voltage pulse of zero module.The output port 2 of positive voltage pulse of zero module is opened with the second selection
The port 1 of pass connects, and the output port 3 of positive voltage pulse of zero module is connect with the port 1 of third selection switch.Reversed zero electricity
The output port 2 of pulse module and the output port 2 of the second selection switch is pressed to connect, the output end of reversed voltage pulse of zero module
Mouth 3 is connect with the output ports 2 of third selection switch.The port 3 of second selection switch and the output of frequency multiplication SPWM modulation module
Port 1 is separately connected two input terminals of first or door, the port 3 of the second selection switch and the output of frequency multiplication SPWM modulation module
Port 2 is separately connected two input terminals of second or door, the port 3 of the second selection switch and the output of frequency multiplication SPWM modulation module
Port 3 is separately connected two input terminals of third or door, the port 3 of the second selection switch and the output of frequency multiplication SPWM modulation module
Port 4 is separately connected two input terminals of the 4th or door.
When the output signal of first comparator is timing, single-phase DC-AC converter work is in positive inverter mode, the first choosing
Selecting switch, the second selection switch, third selects the port 1 of switch to be connected to port 3；The output signal of first comparator is negative
When, single-phase DC-AC converter work selects switch in reversed rectification mode, first choice switch, the second selection switch, third
Port 2 is connected to port 3.
First or door output end be the first bridge arm of inverter upper tube modulated signal vgs1, second or door output end be it is inverse
Become the first bridge arm of device down tube modulated signal vgs4, the output end of third or door is the second bridge arm of inverter upper tube modulated signal vgs2,
4th or door output end be the second bridge arm of inverter down tube modulated signal vgs3.Third select switch 3 output signal of port for
Inverter auxiliary switch modulated signal vgsa。
The amplitude for the first sawtooth carrier wave that positive no-voltage (ZVS) pulse module uses is VtWith-Vt, the first sawtooth carrier wave
Frequency be 2fs, period Ts/2。
In k-th of the triangular carrier cycle, the first sawtooth carrier wave expression formula is vsaw1(t):
First sawtooth carrier wave connects the negative input end of the 4th comparator and the positive input terminal of the 5th comparator.At k-th three
In the carrier cycle of angle, modulation wave amplitude is vm(k), and meet:
0≤|vm(k) | < Vt
The output of absolute value block is | vm(k) |, it is connected to an input terminal of first adder, amount of bias-v1Input the
Another input terminal of one adder.The output end of first adder connects the positive input terminal and second adder of the 4th comparator
An input terminal.Positive modulating wave increment-v2Connect an input terminal of second adder.The output end of second adder connects
Connect the negative input end of the 5th comparator.The output end of 4th comparator and the 5th comparator be separately connected first with two of door it is defeated
Enter end, first connect the input terminal of the 5th rising edge time delay module and the 4th phase inverter with the output end of door, the 4th phase inverter
Output end connects the 6th rising edge time delay module, and the output end of the 5th rising edge time delay module is positive voltage pulse of zero module
Output port 2, i.e., positive bridgc arm short signal output port, the output end of the 6th rising edge time delay module are positive no-voltage arteries and veins
The output port 3 of die block, i.e. auxiliary switch forward direction modulated signal output port.
The amplitude for the second sawtooth carrier wave that reversed no-voltage (ZVS) pulse module uses is VtWith-Vt, the second sawtooth carrier wave
Frequency be 2fs, period Ts/2。
In k-th of the triangular carrier cycle, the second sawtooth carrier wave expression formula is vsaw2(t):
Second sawtooth carrier wave connects the positive input terminal of the 6th comparator and the negative input end of the 7th comparator.Absolute value block
Output be | vm(k) |, it is connected to an input terminal of third adder, amount of bias v1-VtInput another of third adder
Input terminal.The output end of third adder connects the negative input end of the 6th comparator and an input terminal of the 4th adder.Instead
To modulating wave increment v3Connect another input terminal of the 4th adder.The output end of 4th adder connects the 7th comparator
Positive input terminal.The output end of 6th comparator and the 7th comparator is separately connected two input terminals of second Yu door, and second and door
Output end connect the 7th rising edge time delay module and the 5th phase inverter input terminal, the 5th phase inverter output end connection the 8th
Rising edge time delay module, the output end of the 7th rising edge time delay module are the output port 2 of reversed voltage pulse of zero module, i.e., instead
To bridgc arm short signal output port, the output end of the 8th rising edge time delay module is the output end of reversed voltage pulse of zero module
Mouth 3, i.e. auxiliary switch back-modulation signal output port.
Above-mentioned the first rising edge time delay module, the second rising edge time delay module, third rising edge time delay module, on the 4th
It rises along time delay module, the 5th rising edge time delay module, the 6th rising edge time delay module, the 7th rising edge time delay module, the 8th
Liter is that the rising edge of module input signal is delayed along the function of time delay module, remaining moment output signal and input signal phase
Deng.The first rising edge time delay module, the second rising edge time delay module, third rising edge time delay module, the 4th rising edge
The rising edge delay of time delay module is respectively td0, the rising edge delay of the 5th rising edge time delay module is td4, the 6th rising edge prolongs
When module rising edge delay be td5, the rising edge delay of the 7th rising edge time delay module is td6, the 8th rising edge time delay module
Rising edge delay be td7.And it must satisfy:
It is supplied using the single-phase DC-AC converter and auxiliary resonance circuit topology of above-mentioned modulator approach, including inversion direct current side
Power supply Vbus, dc-link capacitance Cbus, there is the full control switch S of anti-paralleled diode by four1、S2、S3、S4The full-bridge of composition
Bridge arm, S1、S2、S3、S4Shunt capacitance C respectively1、C2、C3、C4, output inductor L and alternating current are concatenated between two bridge arm midpoints
Net, in inverter direct-flow side power supply VbusAccess has the auxiliary switch S of anti-paralleled diode between full-bridge bridge armaWith
Clamping capacitance CcSeries arm, auxiliary switch SaShunt capacitance Ca, and resonant inductance L is bridged at series arm both endsr, first
Bridge arm is by main switch S1、S4It constitutes, the second bridge arm is by main switch S2、S3It constitutes.
Modulator approach proposed by the present invention can be realized by analog or digital hardware circuit, can also pass through software mode
It realizes.In the single-phase DC-AC converter bridge arm switch change of current stage, by realizing zero electricity of bridge arm switch for bridge arm voltage resonance to 0
It presses off logical, and inhibits diode reverse recovery.By the way that bridgc arm short pulse is added, magnetizes for resonant inductance and continuous current circuit is provided,
It solves the problems, such as that resonant inductance energy is inadequate, is able to achieve the two-way Sofe Switch work of gamut in the exchange primitive period, Suo Youkai
It closes device and realizes that no-voltage is open-minded, switching loss is small, and circuit efficiency is high, reduces electromagnetic interference.
Detailed description of the invention
Fig. 1 is the producing method of modulator approach proposed by the present invention；
Fig. 2 is frequency multiplication SPWM pulse module internal structure；
Fig. 3 is positive no-voltage (ZVS) pulse module internal structure；
Fig. 4 is reversed no-voltage (ZVS) pulse module internal structure；
Fig. 5 is single-phase DC-AC converter and auxiliary resonance circuit topology；
Fig. 6 is that positive inversion work and modulating wave are more than or equal to each modulated signal wave when zero in a triangular carrier cycle
Shape；
Fig. 7 be in the triangular carrier cycle positive inversion work and modulating wave less than zero constantly each modulated signal waveform；
Fig. 8 is work reversely to be rectified in the triangular carrier cycle and modulating wave is more than or equal to each modulated signal wave when zero
Shape；
Fig. 9 be in the triangular carrier cycle reversely rectify work and modulating wave less than zero constantly each modulated signal waveform；
Figure 10 is that positive inversion work and modulating wave are more than or equal to single-phase DC-AC transformation when zero in a triangular carrier cycle
Device mains voltage current waveform；
Figure 11 is for inversion work positive in the preceding half period of a triangular carrier cycle and when modulating wave is more than or equal to zero
Single-phase each working stage circuit diagram of DC-AC converter；
Figure 12 is work reversely to be rectified in the triangular carrier cycle and modulating wave is more than or equal to single-phase DC-AC transformation when zero
Device mains voltage current waveform；
Figure 13 is in the preceding half period of a triangular carrier cycle when reversely rectifying work and modulating wave and being more than or equal to zero
Single-phase each working stage circuit diagram of DC-AC converter；
Specific embodiment
The present invention is described in detail with reference to the accompanying drawing.
As shown in Figure 1, modulating wave is sent into frequency multiplication SPWM modulation module, modulating wave inputs absolute value block, absolute value simultaneously
Module output is the absolute value of modulating wave, the port 3 of the output signal connection first choice switch of absolute value block.Single-phase DC-
The ac output voltage v of AC converteroWith output electric current ioThe first multiplier, the output end of the first multiplier are inputted after sampled
It is connect with the positive input terminal of first comparator, the negative input end of first comparator is 0.The output signal of first comparator is as choosing
Signal is selected, the port 4 of first choice switch, the second selection switch, third selection switch is separately connected.Modulating wave connects while connecting
Connect the input port 5 of frequency multiplication SPWM modulation module and the input terminal of absolute value block, the output end connection first of absolute value block
Select the port 3 of switch.The port 1 of first choice switch is connect with the input port 1 of positive voltage pulse of zero module, the first choosing
The port 2 for selecting switch is connect with the input port 1 of reversed voltage pulse of zero module.The output port of positive voltage pulse of zero module
2 connect with the port 1 of the second selection switch, the port 1 of output port 3 and third the selection switch of positive voltage pulse of zero module
Connection.The output port 2 of reversed voltage pulse of zero module is connect with the output port 2 of the second selection switch, reversed no-voltage arteries and veins
The output port 3 of die block is connect with the output port 2 of third selection switch.The port 3 of second selection switch and frequency multiplication SPWM
The output port 1 of modulation module is separately connected two input terminals of first or door, the port 3 of the second selection switch and frequency multiplication SPWM
The output port 2 of modulation module is separately connected two input terminals of second or door, the port 3 of the second selection switch and frequency multiplication SPWM
The output port 3 of modulation module is separately connected two input terminals of third or door, the port 3 of the second selection switch and frequency multiplication SPWM
The output port 4 of modulation module is separately connected two input terminals of the 4th or door.
When the output signal of first comparator is timing, single-phase DC-AC converter work is in positive inverter mode, the first choosing
Selecting switch, the second selection switch, third selects the port 1 of switch to be connected to port 3；The output signal of first comparator is negative
When, single-phase DC-AC converter work selects switch in reversed rectification mode, first choice switch, the second selection switch, third
Port 2 is connected to port 3.
First or door output end be the first bridge arm of inverter upper tube modulated signal vgs1, second or door output end be it is inverse
Become the first bridge arm of device down tube modulated signal vgs4, the output end of third or door is the second bridge arm of inverter upper tube modulated signal vgs2,
4th or door output end be the second bridge arm of inverter down tube modulated signal vgs3.Third select switch 3 output signal of port for
Inverter auxiliary switch modulated signal vgsa。
As shown in Fig. 2, the port 5 of modulating wave input frequency multiplication SPWM modulation module, frequency multiplication SPWM modulation module is using symmetrical
Triangular carrier, amplitude VtWith-Vt, carrier frequency fs, carrier cycle Ts.It is f that converter, which exchanges fundamental frequency,g, exchange base
Wave period is Tg.Carrier frequency is the integral multiple of fundamental frequency, within an exchange primitive period, shares N number of frequency multiplication SPWM and carries
Wave period:
In k-th of carrier cycle, triangular carrier expression formula is vtri(t):
In k-th of carrier cycle, 1 amplitude of modulating wave is vm(k):
- 1 < vm(k) 1,1≤k of <≤N
Modulating wave connects the positive input terminal of the second comparator and the input terminal of the first phase inverter, the output end of the first phase inverter
Connect the positive input terminal of third comparator.Triangular carrier connects the negative input end of the second comparator and the negative input of third comparator
End.The input terminal of output the second phase inverter of connection of second comparator and the input terminal of the first rising edge time delay module.Third ratio
Compared with the input terminal of the output connection third phase inverter of device and the input terminal of third rising edge time delay module.The output of second phase inverter
The second rising edge time delay module of end connection, the output end of third phase inverter connect the 4th rising edge time delay module.
The output end of first rising edge time delay module is the output port 1 of frequency multiplication SPWM modulation module, and the second rising edge prolongs
When module output end be frequency multiplication SPWM modulation module output port 2, the output end of third rising edge time delay module is frequency multiplication
The output port 3 of SPWM modulation module, the output end of the 4th rising edge time delay module are the port 4 of frequency multiplication SPWM modulation module.
As shown in figure 3, the amplitude for the first sawtooth carrier wave that positive no-voltage (ZVS) pulse module uses is VtWith-Vt, the
The frequency of one sawtooth carrier wave is 2fs, period Ts/2。
In k-th of the triangular carrier cycle, the first sawtooth carrier wave expression formula is vsaw1(t):
First sawtooth carrier wave connects the negative input end of the 4th comparator and the positive input terminal of the 5th comparator.Absolute value block
Output be | vm(k) |, it is connected to an input terminal of first adder, amount of bias-v1Another of input first adder is defeated
Enter end.The output end of first adder connects the positive input terminal of the 4th comparator and an input terminal of second adder.It is positive
Modulating wave increment-v2Connect an input terminal of second adder.The output end of second adder connects the negative of the 5th comparator
Input terminal.The output end of 4th comparator and the 5th comparator is separately connected two input terminals of first Yu door, first with door
Output end connects the input terminal of the 5th rising edge time delay module and the 4th phase inverter, and the output end of the 4th phase inverter connects on the 6th
It rises along time delay module, the output end of the 5th rising edge time delay module is the output port 2 of positive voltage pulse of zero module, and output is just
To bridgc arm short signal, the output end of the 6th rising edge time delay module is the output port 3 of positive voltage pulse of zero module, output
Auxiliary switch forward direction modulated signal.
As shown in figure 4, the amplitude for the second sawtooth carrier wave that reversed no-voltage (ZVS) pulse module uses is VtWith-Vt, the
The frequency of two sawtooth carrier waves is 2fs, period Ts/2。
In k-th of the triangular carrier cycle, the second sawtooth carrier wave expression formula is vsaw2(t):
Second sawtooth carrier wave connects the negative input end of the 4th comparator and the positive input terminal of the 5th comparator.Absolute value block
Output be | vm(k) |, it is connected to an input terminal of third adder, amount of bias v1-VtInput another of third adder
Input terminal.The output end of third adder connects the negative input end of the 6th comparator and an input terminal of the 4th adder.Instead
To modulating wave increment v3Connect another input terminal of the 4th adder.The output end of 4th adder connects the 7th comparator
Positive input terminal.The output end of 6th comparator and the 7th comparator is separately connected two input terminals of second Yu door, and second and door
Output end connect the 7th rising edge time delay module and the 5th phase inverter input terminal, the 5th phase inverter output end connection the 8th
Rising edge time delay module, the output end of the 7th rising edge time delay module are the output port 2 of reversed voltage pulse of zero module, output
Reversed bridgc arm short signal, the output end of the 8th rising edge time delay module is the output port 3 of reversed voltage pulse of zero module, defeated
Auxiliary switch back-modulation signal out.
Above-mentioned the first rising edge time delay module, the second rising edge time delay module, third rising edge time delay module, on the 4th
It rises along time delay module, the 5th rising edge time delay module, the 6th rising edge time delay module, the 7th rising edge time delay module, the 8th
Liter is that the rising edge of module input signal is delayed along the function of time delay module, remaining moment output signal and input signal phase
Deng.The first rising edge time delay module, the second rising edge time delay module, third rising edge time delay module, the 4th rising edge
The rising edge delay of time delay module is respectively td0, the rising edge delay of the 5th rising edge time delay module is td4, the 6th rising edge prolongs
When module rising edge delay be td5, the rising edge delay of the 7th rising edge time delay module is td6, the 8th rising edge time delay module
Rising edge delay be td7.And it must satisfy:
As shown in figure 5, single-phase DC-AC converter and auxiliary resonance circuit topology that the present invention is applied to, including inversion are straight
Flow side power supply Vbus, dc-link capacitance Cbus, there is the full control switch S of anti-paralleled diode by four1、S2、S3、S4It constitutes
Full-bridge bridge arm, S1、S2、S3、S4Shunt capacitance C respectively1、C2、C3、C4, between two bridge arm midpoints concatenation output inductor L with
AC network, in inverter direct-flow side power supply VbusThere is the auxiliary of anti-paralleled diode to open for access between full-bridge bridge arm
Close SaWith clamping capacitance CcSeries arm, auxiliary switch SaShunt capacitance Ca, and resonant inductance L is bridged at series arm both endsr。
First bridge arm is by main switch S1、S4It constitutes, the second bridge arm is by main switch S2、S3It constitutes.
Referring to Fig. 6, vs1、vs2、vs3、vs4Respectively frequency multiplication SPWM modulation module port 1, port 2, port 3, port 4 it is defeated
Signal waveform out.Positive inversion operating mode and modulating wave are more than or equal to zero, in k-th of the triangular carrier cycle: | vm(k) |=vm
(k).In the preceding half period of triangular carrier, triangular carrier and the first sawtooth carrier wave are equal: vtri(t)=vsaw1Therefore v (t),gsaf
Failing edge lag behind vgs4Failing edge, lag time td1.In the second half of the cycle of triangular carrier, triangular carrier and first
Sawtooth carrier wave reverse phase: vtri(t)=- vsaw1Therefore v (t),gsafFailing edge lag behind vgs2Failing edge, lag time is still
td1, and meet:
Referring to Fig. 7, vs1、vs2、vs3、vs4Respectively frequency multiplication SPWM modulation module port 1, port 2, port 3, port 4 it is defeated
Signal waveform out.Positive inversion operating mode and modulating wave is less than zero, in k-th of the triangular carrier cycle: | vm(k) |=- vm(k)。
In the preceding half period of triangular carrier, triangular carrier and the first sawtooth carrier wave are equal: vtri(t)=vsaw1Therefore v (t),gsafUnder
Drop edge lags behind vgs3Failing edge, lag time is still td1.In the second half of the cycle of triangular carrier, triangular carrier and the first saw
Tooth carrier wave reverse phase: vtri(t)=- vsaw1Therefore v (t),gsafFailing edge lag behind vgs1Failing edge, lag time is still td1。
Referring to Fig. 8, vs1、vs2、vs3、vs4Respectively frequency multiplication SPWM modulation module port 1, port 2, port 3, port 4 it is defeated
Signal waveform out.It reversely rectifies operating mode and modulating wave is more than or equal to zero, in k-th of the triangular carrier cycle: | vm(k) |=vm
(k).In the preceding half period v of triangular carriergsafFailing edge lag behind vgs3Failing edge, lag time is still td1.In triangle
The second half of the cycle of carrier wave, vgsafFailing edge lag behind vgs1Failing edge, lag time be still be td1。
Referring to Fig. 9, vs1、vs2、vs3、vs4Respectively frequency multiplication SPWM modulation module port 1, port 2, port 3, port 4 it is defeated
Signal waveform out.The reversed operating mode and modulating wave of rectifying is less than zero, in k-th of the triangular carrier cycle: | vm(k) |=- vm(k)。
In the preceding half period v of triangular carriergsafFailing edge lag behind vgs4Failing edge, lag time is still td1.In triangular carrier
Second half of the cycle, vgsafFailing edge lag behind vgs2Failing edge, lag time is still td1。
0 and Figure 11 referring to Fig.1, to the single-phase DC-AC converter using modulator approach proposed by the present invention in positive inversion
Each voltage current waveform of operating mode and each working stage circuit are illustrated.To simplify the analysis, current source generation is used in Figure 11
For inductance L and AC network.
One (t of stage0~t1):
Such as Figure 11 (1), main switch S4、S3With auxiliary switch SaConducting, main switch S1、S2Shutdown, by resonant inductance Lr, clamp
Capacitor Cc, auxiliary switch SaIn the circuit of composition, resonant inductance LrBoth end voltage is-Vcc, resonant inductance electric current linear decline；
Two (t of stage1~t2):
Such as Figure 11 (2), in t1Moment, main switch S4Shutdown, S4Middle electric current by its anti-paralleled diode afterflow, and:
td1=t2-t1
Three (t of stage2~t3):
Such as Figure 11 (3), in t2Moment, auxiliary switch SaShutdown, resonant inductance LrGive main switch S1、S2Shunt capacitance C1、
C2Auxiliary switch S is given in electric dischargeaShunt capacitance CaCharging, SaZero voltage turn-off.
Four (t of stage3~t4):
Such as Figure 11 (4), t is arrived3Moment, main switch S1、S2Shunt capacitance C1、C2Voltage resonance is to zero, S1、S2Inverse parallel
Diode is begun to turn on, resonant inductance LrBoth end voltage is clamped in Vbus, resonant inductance LrElectric current linear rise；
Four (t of stage4~t5):
Such as Figure 11 (5), in t4Moment, main switch S1、S2、S4No-voltage is open-minded, resonant inductance LrElectric current continues linear rise,
And:
td4=t4-t2
Five (t of stage5~t6):
Such as Figure 11 (6), in t5It carves, main switch S2、S4Shutdown, resonant inductance LrGive main switch S2、S4Shunt capacitance C2、C4
Auxiliary switch S is given in chargingaShunt capacitance CaElectricity, S2、S4Zero voltage turn-off, and:
td2=t5-t2
td2For by amount of bias-v2The delay time of decision:
Six (t of stage6~t7):
Such as Figure 11 (7), t is arrived6Moment, auxiliary switch SaShunt capacitance CaPress resonance to zero, SaAnti-paralleled diode starts to lead
It is logical, resonant inductance LrBoth end voltage is clamped in-VccBy by clamping capacitance Cc、SaPut magnetic, resonance in the circuit of parallel diode composition
Inductance LrElectric current linear decline；Energy is transmitted from DC power supply to AC network.
Seven (t of stage7~t8):
Such as Figure 11 (8), in t7Moment, auxiliary switch SaNo-voltage is open-minded, resonant inductance LrBoth end voltage is clamped in-Vcc, lead to
It crosses by clamping capacitance Cc、SaPut magnetic, resonant inductance L in the circuit of compositionrElectric current continues linear decline, and:
td5=t7-t5
Eight (t of stage8~t9):
Such as Figure 11 (9), in t8Moment, main switch S3Shutdown, exports electric current and gives main switch S2Shunt capacitance C2Electric discharge, gives
Main switch S3Shunt capacitance C3Charging, S3Zero voltage turn-off；
Nine (t of stage9~t10):
Such as Figure 11 (10), t is arrived9Moment, main switch S2Shunt capacitance C2It is discharged to zero, main switch S2Anti-paralleled diode
It begins to turn on, main switch S2Pipe pressure is clamped to zero, main switch S3Pipe pressure is clamped to Vbus+Vcc, load current is by main switch S2
Anti-paralleled diode afterflow；
Ten (t of stage10~t11):
Such as Figure 11 (11), in t10Moment, main switch S2No-voltage is open-minded, and:
td0=t10-t8
2 and Figure 13 referring to Fig.1 is reversely being rectified to using the single-phase DC-AC converter of modulator approach proposed by the present invention
Each voltage current waveform of operating mode and each working stage circuit are illustrated.To simplify the analysis, current source generation is used in Figure 11
For inductance L and AC network.
One (t of stage0~t1):
Such as Figure 13 (1), main switch S4、S3With auxiliary switch SaConducting, main switch S1、S2Shutdown, by resonant inductance Lr, clamp
Capacitor Cc, auxiliary switch SaIn the circuit of composition, resonant inductance LrBoth end voltage is-Vcc, resonant inductance electric current linear decline；
Two (t of stage1~t2):
Such as Figure 13 (2), in t1Moment, main switch S4Shutdown, input current main switch S4Shunt capacitance C4Electric discharge, to master
Switch S1Shunt capacitance C1Charging, S4Zero voltage turn-off；
Three (t of stage2~t3):
Such as Figure 13 (3), in t2Moment, main switch S1Shunt capacitance C1It is discharged to zero, main switch S1Anti-paralleled diode is opened
Begin to be connected, main switch S1Pipe pressure is clamped to zero, main switch S4Pipe pressure is clamped to Vbus+Vcc, input current is by main switch S1Instead
Parallel diode afterflow.Energy is from AC network to DC side power delivery.
Four (t of stage3~t4):
Such as Figure 13 (4), t is arrived3Moment, main switch S2No-voltage is open-minded, and:
td0=t3-t1
Four (t of stage4~t5):
Such as Figure 13 (5), t is arrived4Moment, main switch S3Shutdown, S3Middle electric current is by its anti-paralleled diode afterflow.And:
td1=t5-t4
Five (t of stage5~t6):
Such as Figure 13 (6), in t5Moment, auxiliary switch SaShutdown, resonant inductance LrGive main switch S2、S4Shunt capacitance C2、
C4Auxiliary switch S is given in electric dischargeaShunt capacitance CaCharging, SaZero voltage turn-off.
Six (t of stage6~t7):
Such as Figure 13 (7), t is arrived6Moment, main switch S2、S4Shunt capacitance C2、C4Voltage resonance is to zero, S2、S4Inverse parallel
Diode is begun to turn on, resonant inductance LrBoth end voltage is clamped in Vbus, resonant inductance LrElectric current linear rise；
Seven (t of stage7~t8):
Such as Figure 13 (8), in t7Moment, main switch S2、S3、S4No-voltage is open-minded, resonant inductance LrElectric current continues linear rise,
And:
td6=t7-t5
Eight (t of stage8~t9):
Such as Figure 13 (9), in t8It carves, main switch S3、S4Shutdown, resonant inductance LrGive main switch S3、S4Shunt capacitance C3、C4
Auxiliary switch S is given in chargingaShunt capacitance CaElectricity, S3、S4Zero voltage turn-off, and:
td3=t8-t5
td3For by amount of bias v3The delay time of decision:
Nine (t of stage9~t10):
Such as Figure 13 (10), t is arrived9Moment, auxiliary switch SaShunt capacitance CaPress resonance to zero, SaAnti-paralleled diode starts
Conducting, resonant inductance LrBoth end voltage is clamped in-VccBy by clamping capacitance Cc、SaMagnetic is put in the circuit of parallel diode composition, humorous
Shake inductance LrElectric current linear decline.
Ten (t of stage10~t11):
Such as Figure 13 (11), in t70Moment, auxiliary switch SaNo-voltage is open-minded, resonant inductance LrBoth end voltage is clamped in-Vcc,
By by clamping capacitance Cc、SaPut magnetic, resonant inductance L in the circuit of compositionrElectric current continues linear decline, and:
td7=t10-t8。
Claims (6)
1. a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter, which is characterized in that the modulator approach is applied to
Single-phase DC-AC converter and auxiliary resonance circuit topology, including inversion direct current side power supply Vbus, dc-link capacitance Cbus,
There is the full control switch S of anti-paralleled diode by four1、S2、S3、S4The full-bridge bridge arm of composition, S1、S2、S3、S4Shunt capacitance respectively
C1、C2、C3、C4, output inductor L and AC network are concatenated between two bridge arm midpoints, in inverter direct-flow side power supply
VbusAccess has the auxiliary switch S of anti-paralleled diode between full-bridge bridge armaWith clamping capacitance CcSeries arm, auxiliary opens
Close SaShunt capacitance Ca, and resonant inductance L is bridged at series arm both endsr, the first bridge arm is by main switch S1、S4It constitutes, the second bridge
Arm is by main switch S2、S3It constitutes；
The modulator approach includes: to provide positive no-voltage (ZVS) pulse module (7), and it is positive to generate auxiliary switch all the way
Modulated signal vgsafPositive bridgc arm short signal v all the wayscf；
One reversed no-voltage (ZVS) pulse module (8) is provided, auxiliary switch back-modulation signal v all the way is generatedgsarAll the way
Reversed bridgc arm short signal vscr；
Positive voltage pulse of zero module (7) or reversed voltage pulse of zero module are selected according to converter alternating voltage current polarity
(8): polarity is timing, selects positive voltage pulse of zero module, when polarity is negative, selects reversed voltage pulse of zero module, will just
The reversed bridge that the positive bridgc arm short signal or reversed voltage pulse of zero module (8) exported to voltage pulse of zero module (7) exports
Arm short-circuit signal and four tunnel modulated signals of frequency multiplication SPWM modulation module (6) output carry out logical "or" operation respectively；And it will just
The auxiliary switch forward direction modulated signal or reversed voltage pulse of zero module (8) exported to voltage pulse of zero module (7) exports auxiliary
Help modulated signal (19) of the switch back-modulation signal as auxiliary switch.
2. a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter according to claim 1, feature exist
In the modulating wave (1) of single-phase DC-AC converter inputs frequency multiplication SPWM modulation module (6) and absolute value block (3) simultaneously, absolutely
It is worth the port 3 of the output signal connection first choice switch (5) of module (3), the ac output voltage v of single-phase DC-AC convertero
With output electric current ioThe first multiplier (2) are inputted after sampled, output end and first comparator (4) of the first multiplier (2)
Positive input terminal connection, the negative input end of first comparator (4) are 0, the output signal of first comparator (4) alternatively signal,
It is separately connected the port 4 of first choice switch (5), the second selection switch (9), third selection switch (10), first choice switch
(5) port 1 connect with the input port 1 of positive voltage pulse of zero module (7), first choice switch the port 2 of (5) with reversely
The input port 1 of voltage pulse of zero module (8) connects, and the output port 2 of positive voltage pulse of zero module (7) is opened with the second selection
The port 1 for closing (9) connects, and the port 1 of output port 3 and third the selection switch (10) of positive voltage pulse of zero module (7) connects
It connects, the output port 2 of reversed voltage pulse of zero module (8) is connect with the port 2 of the second selection switch (9), reversed no-voltage arteries and veins
The output port 3 of die block (8) and third select the port 2 of switch (10) connect, the port 3 of the second selection switch (9) with again
The output port 1 of frequency SPWM modulation module (6) is separately connected two input terminals of first or door (11), the second selection switch (9)
Port 3 and the output port 2 of frequency multiplication SPWM modulation module (6) be separately connected two input terminals of second or door (12), second
The port 3 of selection switch (9) and the output port 3 of frequency multiplication SPWM modulation module (6) are separately connected two of third or door (13)
Input terminal, the port 3 of the second selection switch (9) and the output port 4 of frequency multiplication SPWM modulation module (6) are separately connected the 4th or door
(14) two input terminals；
The output signal of first comparator (4) is timing, and single-phase DC-AC converter work is in positive inverter mode, first choice
Switch (5), the second selection switch (9), third select the port 1 of switch (10) to be connected to port 3；First comparator (4) it is defeated
When signal is negative out, in reversed rectification mode, first choice switchs (5), the second selection switch for single-phase DC-AC converter work
(9), the port 2 of third selection switch (10) is connected to port 3；
First or door (11) output end be inverter the first bridge arm upper tube modulated signal (15) vgs1, second or door (12) it is defeated
Outlet is inverter the first bridge arm down tube modulated signal (16) vgs4, the output end of third or door (13) is the second bridge arm of inverter
Upper tube modulated signal (17) vgs2, the 4th or door (14) output end be inverter the second bridge arm down tube modulated signal (18) vgs3；
It is inverter auxiliary switch modulated signal (19) v that third, which selects 3 output signal of port of switch (10),gsa。
3. a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter according to claim 2, feature exist
In the modulating wave (1) inputs frequency multiplication SPWM modulation module (6), and frequency multiplication SPWM modulation module (6) uses symmetric triangular carrier wave
(20), amplitude VtWith-Vt, carrier frequency fs, carrier cycle Ts；It is f that converter, which exchanges fundamental frequency,g, exchange fundamental wave week
Phase is Tg；Carrier frequency is the integral multiple of fundamental frequency, within an exchange primitive period, shares N number of frequency multiplication SPWM carrier cycle
Phase:
In k-th of carrier cycle (1≤k≤N), triangular carrier expression formula is vtri(t):
In k-th of carrier cycle, modulating wave (1) amplitude is vm(k):
-Vt< vm(k) < Vt,1≤k≤N
Modulating wave (1) connects the positive input terminal of the second comparator (22) and the input terminal of the first phase inverter (21), the first phase inverter
(21) positive input terminal of output end connection third comparator (23), bearing for triangular carrier (20) connection the second comparator (22) are defeated
Enter the negative input end at end and third comparator (23), the input terminal of the output connection the second phase inverter (24) of the second comparator (22)
With the input terminal of the first rising edge time delay module (26), the input of output connection third phase inverter (25) of third comparator (23)
The input terminal at end and third rising edge time delay module (28), the output end of the second phase inverter (24) connect the second rising edge delay mould
The output end of block (27), third phase inverter (25) connects the 4th rising edge time delay module (29)；
The output end of first rising edge time delay module (26) is the output port 1 of frequency multiplication SPWM modulation module (6), the second rising edge
The output end of time delay module (27) is the output port 2 of frequency multiplication SPWM modulation module (6), third rising edge time delay module (28)
Output end is the output port 3 of frequency multiplication SPWM modulation module (6), and the output end of the 4th rising edge time delay module (29) is frequency multiplication
The output port 4 of SPWM modulation module (6).
4. a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter according to claim 1, feature exist
In the amplitude for the first sawtooth carrier wave (30) that positive no-voltage (ZVS) pulse module (7) uses is VtWith-Vt, first
The frequency of sawtooth carrier wave (30) is 2fs, period Ts/2；
Within k-th of triangular carrier (20) period, the first sawtooth carrier wave (30) expression formula is vsaw1(t):
First sawtooth carrier wave (30) connects the negative input end of the 4th comparator (33) and the positive input terminal of the 5th comparator (34), absolutely
Output to value module (3) is | vm(k) |, it is connected to an input terminal of first adder (31), amount of bias-v1Input first
Another input terminal of adder (31), the output end of first adder (31) connect the 4th comparator (33) positive input terminal and
One input terminal of second adder (32), positive modulating wave increment-v2An input terminal of second adder (32) is connected, the
The output end of two adders (32) connects the negative input end of the 5th comparator (34), the 4th comparator (33) and the 5th comparator
(34) output end is separately connected two input terminals of first Yu door (35), and first connect the 5th rising with the output end of door (35)
Along the input terminal of time delay module (37) and the 4th phase inverter (36), the output end of the 4th phase inverter (36) connects the 6th rising edge and prolongs
When module (38), the output end of the 5th rising edge time delay module (37) is the output port 2 of positive voltage pulse of zero module (7),
Positive bridgc arm short signal is exported, the output end of the 6th rising edge time delay module (38) is positive voltage pulse of zero module (7)
Output port 3 exports auxiliary switch forward direction modulated signal.
5. a kind of two-way zero voltage switch modulator approach of single-phase DC-AC converter according to claim 1, feature exist
In the amplitude for the second sawtooth carrier wave (39) that reversed no-voltage (ZVS) pulse module (8) uses is VtWith-Vt, second
The frequency of sawtooth carrier wave (39) is 2fs, period Ts/2；
Within k-th of triangular carrier (20) period, the second sawtooth carrier wave (39) expression formula is vsaw2(t):
Second sawtooth carrier wave (39) connects the positive input terminal of the 6th comparator (42) and the negative input end of the 7th comparator (43), absolutely
Output to value module (3) is | vm(k) |, it is connected to an input terminal of third adder (40), amount of bias v1-VtInput the
Another input terminal of three adders (40), the output end of third adder (40) connect the negative input end of the 6th comparator (42)
With an input terminal of the 4th adder (41), back-modulation wave increment v3Connect another input of the 4th adder (41)
End, the output end of the 4th adder (41) connect the positive input terminal of the 7th comparator (43), the 6th comparator (42) and the 7th ratio
Compared with two input terminals that the output end of device (43) is separately connected second Yu door (44), second connect the 7th with the output end of door (44)
The output end connection the 8th of the input terminal of rising edge time delay module (46) and the 5th phase inverter (45), the 5th phase inverter (45) rises
Along time delay module (47), the output end of the 7th rising edge time delay module (46) is the port 2 of reversed voltage pulse of zero module (8),
Reversed bridgc arm short signal is exported, the output end of the 8th rising edge time delay module (47) is reversed voltage pulse of zero module (8)
Port 3 exports auxiliary switch back-modulation signal.
6. according to a kind of described in any item two-way zero voltage switch modulation methods of single-phase DC-AC converter of claim 3~5
Method, it is characterised in that the first rising edge time delay module (26), the second rising edge time delay module (27), third rising edge prolong
When module (28), the 4th rising edge time delay module (29), the 5th rising edge time delay module (37), the 6th rising edge time delay module
(38), the 7th rising edge time delay module (47), the 8th rising edge time delay module (48) function be by the upper of module input signal
It rises along delay, remaining moment output signal is equal with input signal, and the first rising edge time delay module (26), second rise
Rising edge delay along time delay module (27), third rising edge time delay module (28), the 4th rising edge time delay module (29) is td0,
The rising edge delay of 5th rising edge time delay module (37) is td4, the rising edge of the 6th rising edge time delay module (38), which is delayed, is
td5, the rising edge delay of the 7th rising edge time delay module (47) is td6, the rising edge delay of the 8th rising edge time delay module (48)
For td7；And it must satisfy:
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| CN103001523A (en) * | 2012-10-31 | 2013-03-27 | 上海交通大学 | Zero-voltage switching energy storage bridge-type inverter without additional voltage and modulation method for inverter |
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| CN103001523A (en) * | 2012-10-31 | 2013-03-27 | 上海交通大学 | Zero-voltage switching energy storage bridge-type inverter without additional voltage and modulation method for inverter |
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