CN101888174A - Power inverter - Google Patents
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- CN101888174A CN101888174A CN2010102435917A CN201010243591A CN101888174A CN 101888174 A CN101888174 A CN 101888174A CN 2010102435917 A CN2010102435917 A CN 2010102435917A CN 201010243591 A CN201010243591 A CN 201010243591A CN 101888174 A CN101888174 A CN 101888174A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
Power inverter of the present invention can make under the pattern of continuous input current while carrying out the power-factor improvement control output voltage, and can reduce the switching losses relevant with power conversions.Have: first and the second switch arm, inverse parallel connects switch element and diode, and is connected in series and forms in the mode of the mutual reversed polarity of diode; Inductor, it is in series inserted in the circuit that first switch arm and AC power AC are connected in parallel; Capacitor, it is in series inserted in the circuit that second switch arm and first switch arm are connected in parallel; And output circuit, it has the capacitor that is connected in parallel with first switch arm and the series circuit of inductor, error and polarity of voltage according to output order value and output detected value, in switch element, make the alternatively conducting shutoff of switch element of bearing input current and output control, make the conducting of the opposing party's switch element.
Description
The application be on May 14th, 2008 that submit, application number be 2008101078258, denomination of invention divides an application for the patent application of " power inverter ".
Technical field
The present invention relates to the interchange of power supply is converted to the direct current of variable voltage or the power inverter of interchange, particularly make the technology of the loss reduction of the thyristor that constitutes power conversion circuit.
Background technology
AC supply voltage is being converted in the power inverter of direct current, known to the insulation type ac-dc transducer with AC power and load insulation such as transformer.As an example of such insulation type ac-dc transducer, the one-part form transducer of putting down in writing among Fig. 1 of patent documentation 1 with power-factor improvement function has been proposed.According to this transducer, the series circuit of two diodes, the series circuit and the capacitor of two bidirectional switchs (parallel circuits of self-extinction of arc semiconductor switch and diode) are connected in parallel mutually, in being connected in series a little of two diodes and being connected in series a little of two bidirectional switchs, connect AC power via inductor, to the be connected in parallel series circuit of transformer and inductor and capacitor of a side bidirectional switch wherein, constitute main switch circuit.And, after the secondary side of the transformer of main switch circuit is provided with the centre cap diode rectifier circuit, is converted to direct current, export.
The control circuit of the control main switch circuit of patent documentation 1 changes the triangle wave frequency for the deviation of the command value that reduces VD and detected value, relatively this triangular wave and constant reference signal (for example 1/2 of the peak value of triangular wave), the switching frequency of the conducting cut-off signals of two bidirectional switchs of control is controlled VD.Thus, because flow through the input current of triangular wave shape, can access the effect of power-factor improvement according to the instantaneous value of AC supply voltage.
In addition, in Fig. 3 of patent documentation 1, put down in writing a kind of control circuit, the command value of the terminal voltage of the capacitor that it is connected in parallel for the series circuit that reduces with two bidirectional switchs and the deviation of detected value, change the reference signal that compares with triangular wave, change the ratio of the conducting shutoff of two bidirectional switchs.
And, the main switch circuit of in Fig. 9, Figure 13 of patent documentation 1, putting down in writing first～the 3rd bidirectional switch that is connected in series, the series circuit and the capacitor of two diodes are connected in parallel respectively on this series circuit, the second and the 3rd bidirectional switch be connected in series a little and two diodes be connected in series a little between connect AC power via inductor, with the be connected in parallel series circuit of transformer and capacitor and capacitor of the series circuit of the second and the 3rd bidirectional switch, constitute main switch circuit.And, at the secondary side of the transformer of main switch circuit the centre cap diode rectifier circuit is set, be converted to the laggard line output of direct current.The control circuit of these bidirectional switchs is divided into first bidirectional switch, two groups of the second and the 3rd bidirectional switch, and is identical with above-mentioned control circuit, constitutes the consistent alternatively control switch of polarity with alternating voltage.
[patent documentation 1] spy opens the 2003-23775 communique
But according to the control circuit of Fig. 1 of patent documentation 1, the conducting of two bidirectional switchs is turn-offed than irrelevant with switching frequency, is 0.5: 0.5 constant ratio.On the other hand, according to the control circuit of Fig. 3, the conducting of two bidirectional switchs is turn-offed than changing.Which kind of situation no matter, the input current of the transducer of patent documentation 1 be in the conduction period of bidirectional switch, flows and the instantaneous voltage of power supply proportional electric current substantially, becomes the electric current that is reduced to the wavy interrupted impulse waveform of zero triangle at blocking interval.If the triangular pulse electric current zero during be unlimited short critical conduction mode, then the current waveform that obtains by low pass filter is a perfect sine wave.But, change in order to control the output dc voltage switching frequency, thus exist to produce the triangular pulse electric current zero during, the problem of input current waveform distortion.In addition, at electric power hour, even under such discontinuous current pattern, also can carry out power-factor improvement, but when electric power becomes big, the peak value of triangular pulse electric current becomes greatly.Therefore, existing needs the unsaturated such big iron core of inductor, in order to cut off big peak current, the problem that the switching losses of switching circuit increases.
These problems are not limited to the insulation type ac-dc transducer, Yi Bian carrying out the power-factor improvement control that power supply exchanges, also have common problem Yi Bian be converted in the power inverter of interchange of variable voltage.
Summary of the invention
The problem that the present invention will solve is to provide a kind of power inverter, this power inverter can be controlled output power while carrying out power-factor improvement making under the pattern of continuous input current, and can lower the switching losses relevant with power conversions.
In order to solve above-mentioned problem, being characterized as of first form of power inverter of the present invention, have: first and the second switch arm, two switching circuits that inverse parallel connected thyristor and diode and constitute are so that the mode of the mutual reversed polarity of described diode is connected in series and forms; First inductor, it in series inserts in the circuit that first switch arm and AC power are connected in parallel; First capacitor, it in series inserts in the circuit that second switch arm and first switch arm are connected in parallel; And output circuit, its have with first switch arm and second switch arm in second capacitor that is connected in parallel of a certain side and the series circuit of second inductor, constitute main switch circuit thus.
By constituting such main switch circuit, and each thyristor is carried out the control circuit that control is turn-offed in conducting by constituting as follows, can control output power while carrying out power-factor improvement making under the pattern of continuous input current, and can lower the switching losses relevant with power conversions.
Promptly, the control circuit of controlling is turn-offed in the conducting of each thyristor can be according to output order value and the error of output detected value and the polarity of voltage of AC power of output circuit, in the thyristor (Q1, Q2, Q3, Q4) of first and second switch arms, make the alternatively conducting shutoff of thyristor (for example Q1, Q3) of bearing input current and output control, make the opposing party's thyristor (Q2, Q4) conducting.Specifically, can obtain the output order value of output circuit and the error of output detected value, the absolute value that this error be multiply by the voltage detecting value of AC power generates the input current command value, and obtain the input current command value and from the error of the absolute value of the input current detected value of AC power, this sum of errors PWM carrier wave compared generate pwm signal, polarity of voltage according to this pwm signal and described AC power, in the thyristor of first and second switch arms, make the alternatively conducting shutoff of thyristor of bearing input current and output control, make the opposing party's thyristor conducting.
So, the thyristor (for example Q1, Q3) of first and second switch arms is alternatively moved, make other thyristor (Q2, Q4) conducting, thus, can eliminate input current and be zero during, carry out the improvement of power factor with the continuous current pattern, can carry out variable control to the voltage or the electric current of output circuit output simultaneously.In addition, because do not need to be provided with the inductor of big iron core,, can lower the switching losses relevant with power conversions so can realize the miniaturization of inductor.
In addition, in first mode, output circuit comprises: the series circuit of second capacitor and second inductor, and this second inductor comprises the primary winding of transformer at least; And the rectification circuit that is connected with the secondary coil of transformer, can export by rectification circuit and carry out direct current after the rectification.At this moment, transformer has two secondary coils, and rectification circuit has: two rectification circuits, and they carry out rectification to the voltage of two secondary coils respectively; With the 3rd capacitor, it is used to make the output voltage of these two rectification circuits level and smooth, the terminal voltage of the 3rd capacitor can be exported as direct current.
In addition, in first mode, second inductor as output circuit can use the load coil as load, can access the interchange output of variable current thus.The control circuit of this moment can detect the output voltage that the output current that flows through load coil replaces the output circuit of above-mentioned control circuit, and the error of output current of in first amplifying unit survey being examined and output current command value is amplified.
Second mode about power inverter of the present invention has: rectifier arm, with first diode and second diode along polarity be connected in series and form; First switch arm connects thyristor and diode to inverse parallel and first and second switching circuits that form, so that the mode of the mutual reversed polarity of described diode is connected in series and forms; The second switch arm is in that inverse parallel is connected and is connected in series first capacitor on the 3rd switching circuit that forms and forms with diode with thyristor; And output circuit, it has the series circuit of second capacitor and second inductor, the described rectifier arm and first switch arm are connected in parallel, at first diode of described rectifier arm and the tie point of second diode, and between the tie point of first and second switching circuits of first switch arm, connect AC power via first inductor, the series circuit of second capacitor and second inductor and described rectifier arm and first switch arm are connected in parallel, second switch arm and described rectifier arm and first switch arm are connected in parallel, and perhaps being connected in parallel with second inductor of described output circuit constitutes main switch circuit.And, also has control circuit, its conducting to described each thyristor is turn-offed and is controlled, described control circuit has: output control system, it turn-offs the thyristor conducting of first and second switching circuits according to the output order value of described output circuit and the output voltage error of output detected value; And power-factor improvement control system, the input current command value that it generates according to the voltage detecting value that described output voltage error be multiply by described AC power and from the bigger side's of the input current error of the input current detected value of described AC power and described output voltage error error, the thyristor conducting of first and second switching circuits is turn-offed, at least one side of the thyristor of first and second switching circuits turn-off during, make the thyristor conducting of the 3rd switching circuit.In addition, output circuit can be identical with the structure of first mode.
According to second mode, turn-off by conducting according to the thyristor of ERROR CONTROL first and second switching circuits of a bigger side in the input current sum of errors output voltage error, and preferentially control by making output (voltage or electric current) control system specific power factor improve control system, can make output (voltage or electric current) stable, the result can suppress the distortion of input current waveform.In addition, identical with first mode, while can carry out power-factor improvement under the pattern of continuous input current and control output power making, and the attenuating switching losses relevant with power conversions.
According to the present invention, while can carry out power-factor improvement under the pattern of continuous input current and control output power making, and can lower the switching losses relevant with power conversions.
Description of drawings
Fig. 1 is the circuit structure diagram of power inverter of using first mode of the embodiment of the invention 1.
Fig. 2 is the action waveforms of embodiment 1.
Fig. 3 is the pattern key diagram of embodiment 1.
Fig. 4 is the circuit structure diagram of power inverter of using first mode of the embodiment of the invention 2.
Fig. 5 is the circuit structure diagram of power inverter of using second mode of the embodiment of the invention 3.
Fig. 6 illustrates the control action of embodiment 4.
Fig. 7 illustrates the control action of embodiment 4.
Fig. 8 is the pattern key diagram of embodiment 4.
Fig. 9 is the pattern key diagram of embodiment 4.
Figure 10 is the circuit structure diagram of power inverter of using second mode of the embodiment of the invention 4.
Figure 11 is the circuit structure diagram of power inverter of using second mode of the embodiment of the invention 5.
Symbol description
The AC AC power, L1, the L2 inductor, Q1～Q4 switch element, D1～D6, D11, D12 ... diode, C1～C3 capacitor, T1 transformer, N1～N3 coil, 10 switching circuits, Lr load coil, 71 input voltage detection circuits, 72 output voltage detecting circuits, 73,80 current sensors, 74 input current testing circuits, 75 drive circuits, 76 positive and negative judging circuits, 77,79 comparison amplifiers, 78 multipliers, 81 output current detection circuits, 90 power-factor improvement control system, 91,92 absolute value circuits, 93 maximum value circuits, 94, the 96PWM signal generating circuit, 95 output voltage control system, 97 drive signal generation circuits
Embodiment
Below, the execution mode of power inverter of the present invention is described.
[embodiment 1]
Fig. 1 has represented to use the circuit structure diagram of embodiment 1 of first mode of power inverter of the present invention.As shown in Figure 1, switching circuit 10 has first two-way switch arm and two-way second switch arm, about the first two-way switch arm, to distinguish inverse parallel and connect diode D1, two thyristor Q1 of D2, the bidirectional switch circuit that Q2 constitutes, so that diode D1, the mode of the mutual reversed polarity of D2 is connected in series and forms, about two-way second switch arm, to distinguish inverse parallel ground and connect diode D3, two thyristor Q3 of D4, the bidirectional switch circuit that Q4 constitutes is so that diode D3, the mode of the mutual reversed polarity of D4 is connected in series and forms.
First switch arm is connected in parallel via inductor L1 and AC power AC.The second switch arm is connected in parallel via the capacitor C1 and first switch arm.In addition, on first switch arm, the be connected in parallel primary winding of inductor L2 and transformer T1 and the series circuit of capacitor C2.In addition, this series circuit also can be connected in parallel with the second switch arm.In addition, inductor L2 also can utilize the leakage inductance of transformer T1.
Two secondary coil N2, N3 are set on transformer T1.Each secondary coil N2, N3 make level and smooth by the voltage after diode D5, the D6 rectification respectively by capacitor C3, then to load RL output dc voltage.The output circuit of present embodiment comprises primary winding and the series circuit of capacitor C2, secondary coil N2, the N3 of transformer T1 and the rectification circuit of diode D5, D6 and capacitor C3 formation of inductor L2 and transformer T1.
The switching circuit 10 that is made of first, second switch arm drives by drive circuit 75.75 couples of drive signal Q1～Q4-Duty from control circuit output of drive circuit amplify, and control the conducting of each thyristor Q1～Q4 and turn-off.
The control circuit of present embodiment comprises input voltage detection circuit 71, current sensor 73, input current testing circuit 74, positive and negative judging circuit 76, output voltage detecting circuit 72, pwm signal generative circuit 94, drive signal generation circuit 97.
Input voltage detection circuit 71 detects the alternating voltage of AC power AC, inputs to absolute value circuit 91 and goes into.Absolute value circuit 91 is obtained the absolute value of alternating voltage detected value, inputs to multiplier 78.Current sensor 73 detects the input current that flows through AC power AC, inputs to input current testing circuit 74.Input current testing circuit 74 is to absolute value circuit 92 input input currents.Absolute value circuit 92 is obtained the absolute value of input current detected value, inputs to amplifier 79.Positive and negative judging circuit 76 is output as timing at input voltage detection circuit 71, output " H " signal, output " L " signal when being negative.
Output voltage detecting circuit 72 detects the terminal voltage of the capacitor C3 of output circuit, and the output voltage detected value is inputed to comparison amplifier 77.Comparison amplifier 77 compares the output voltage command value and the output voltage detected value is obtained error, inputs to multiplier 78 after this error is amplified.The error of 78 pairs of output voltage command value of multiplier and output voltage detected value multiply by the absolute value of alternating voltage detected value, inputs to comparison amplifier 79 as the input current command value.The input current command value that comparison amplifier 79 is relatively imported and the absolute value of input current detected value are obtained error, input to pwm signal generative circuit 94 after amplifying this error.
94 pairs of pwm signal generative circuits compare from the input current command value of comparison amplifier 79 outputs and error and the PWM carrier wave of input current detected value, and the generation pwm signal inputs to drive signal generation circuit 97 then.Drive signal generation circuit 97 is made of a plurality of gates, according to the pwm signal from 94 inputs of pwm signal generative circuit, generates drive signal Q1～Q4-Duty of each switch element Q1～Q4.Promptly, with polarity of voltage from the AC power AC of positive and negative judging circuit 76 outputs be just " H " half period and for the half period of bearing " L " consistent, be created among the switch element Q1～Q4 of first and second switch arms, make switch element (Q1, Q3) or (Q2, Q4) alternatively conducting shutoff of bearing input current and output control, make the opposing party's switch element (Q2, Q4) or the drive signal of (Q1, Q3) conducting.
Below, the action of the embodiment 1 of formation like this is described.Fig. 2 represents the drive signal of each switch element of the voltage V (AC) of AC power AC and input current I (AC) and switching circuit 10.Drive signal generation circuit 97 is timing at the polarity of voltage of AC power AC, makes switch element Q2, Q4 become conducting state, makes alternatively conducting shutoff of switch element Q1 and Q3.Otherwise when negative, making switch element Q1 and Q3 is conducting state in polarity, make switch element Q2 and Q4 alternatively conducting turn-off.
Fig. 3 represents that the polarity of voltage of AC power AC is timing, the current waveform I (D5) of the electric current of the drive signal of each switch element and element current and inductor L1 and secondary side rectifier diode D5.Flow through electric current I (Q1) in the path at AC-L1-Q1-Q2 when switch element Q1 conducting, stored energy I (L1) in inductor L1.On the other hand, in DC-DC transducer one side,, in the path of C2-N1-L2-Q1-Q2, flow through electric current I (Q2), stored energy in transformer T1 by the stored charge of capacitor C2.Here, switch element Q2 becomes synchronous rectification action, even be the MOSFET of the little super knot of high withstand voltage conducting resistance (super junction) structure by using, can reduce conducting loss.
Then, when Q1 turn-offs,, in the path of the path of L1-Q4-D3-C1-AC and L2-Q4-D3-C1-C2-N1, flow through back flow current by the stored energy of inductor L1, L2.During this period when the Q3 conducting time, in the path of the path of L1-Q4-Q3-C1-AC and L2-Q4-Q3-C1-C2-N1, flow through electric current I (Q3).Because Q3 is at the state of D3 conducting, promptly element voltage is conducting under the state of zero volt, so become zero volt switch (being called ZVS later on) action, the conducting loss does not take place.
On the other hand, in stored energy the path at N2-D5-C3 of secondary side, flow through electric current, provide electric power to outlet side by the flyback action by transformer T1.So, be timing at the polarity of voltage of AC, providing and receiving of electric power is provided between N1 and N2.When the stored energy of L2 became zero, the stored energy by L1 was in the path of AC-L1-L2-N1-C2 relaying afterflow overcurrent.On the other hand, in DC-DC transducer one side, the stored charge by capacitor C1 flows through electric current I (Q3) in the path of C1-Q3-Q4-L2-N1-C2.Then, when Q3 turn-offed, the stored energy by L2 flow through electric current in the path of L2-N1-C2-Q2-D1, during this period by making the Q1 conducting can realize the ZVS action.
When the stored energy of L2 becomes zero, return the pattern of stored energy in above-mentioned L1, T1, during the polarity of voltage of AC is positive, repeat this action later on.When negative, effect and switch element Q1, the Q3 with Q2, Q4 replaces respectively at the polarity of voltage of AC, carries out providing and receiving of electric power between the N1 of transformer T1 and N3.Like this, in the continuous current mode of the electric current continuous flow of L1,, can drive with the ZVS action switch element Q1 to Q4 by using the stored energy of inductor L2.
As mentioned above, in the present embodiment, output voltage error according to output voltage command value of obtaining by comparison amplifier 77 and output voltage detected value, and from the polarity of voltage of the AC power of positive and negative judging circuit 76 outputs, thyristor (Q1 at first and second switch arms, Q2, Q3, Q4) in, make the thyristor of bearing input current and output control (Q1 for example, Q3) alternatively conducting is turn-offed, make the opposing party's thyristor (Q2, Q4) conducting, therefore do not have input current be zero during, can under continuous current mode, carry out power-factor improvement, simultaneously can carry out variable control output voltage as the terminal voltage of capacitor C3.In addition, because do not need to be provided with the inductor of big iron core,, can lower the switching losses relevant with power conversions so can realize the miniaturization of inductor.
In addition, in the present embodiment,, also cross the electric current of L1, and can carry out the ZVS action of whole switch elements with above-mentioned identical Continuous Flow even the series circuit of inductor L2, primary winding N1, capacitor C2 and the second bidirectional switch arm are connected in parallel.
In addition, though not shown among Fig. 1, by on each switch element Q1～Q4, connecting buffer condenser, and the cut-out electric current when turn-offing by each switch element, buffer condenser is charged or discharges, can suppress the variation of voltage that element is applied thus, lower and turn-off loss.In addition, though buffer condenser first or the second switch arm between connect and also can obtain identical effect.
In addition, in Fig. 1, used MOSFET, but also can replace it to use IGBT or transistor as switch element.
In addition, the power semiconductor switch element formation first or the second switch arm with reverse withstand voltage function that also can use inverse parallel to connect.
And then diode D5, D6 also can be replaced into the circuit of synchronous rectification that uses MOSFET.
In addition, in the present embodiment, represented the example that the second switch arm is connected in parallel via the capacitor C1 and first switch arm, but also capacitor C1 one side can be connected with the tie point of capacitor C2 with transformer T1.That is, can be connected in parallel the series circuit of second switch arm via capacitor C1 and inductor L2 and transformer T1.
[embodiment 2]
Fig. 4 represents to use the circuit structure diagram of embodiment 2 of first mode of power inverter of the present invention.As shown in Figure 4, present embodiment alternating electromotive force is converted on the alternating electromotive force this point different with embodiment 1.Give identical symbol for the part identical, and omit explanation with Fig. 1.
Present embodiment is to flow through high-frequency ac current in load coil Lr, the heating object of metal is carried out the example of the power inverter of electromagnetic induction heating.Though heating object is not shown, with load coil Lr magnetic coupling.
As shown in the figure, the output circuit of present embodiment is made of the series circuit of the second capacitor C2 and load coil Lr.Then, detect the output current that flows through load coil Lr by current sensor 80 and output current detection circuit 81, in comparison amplifier 77, obtain with the error of output current instruction and amplify,, switch element Q1～Q4 is carried out switch control in order to reduce this error.
Therefore, by present embodiment, can access the effect identical with embodiment 1, in addition, the output current that load coil Lr can be provided is controlled to be command value.
[embodiment 3]
Fig. 5 represents to use the circuit structure diagram of embodiment 3 of second mode of power inverter of the present invention.As shown in Figure 5, rectifier arm by along polarity be connected in series diode D11 and diode D12 form.About first switch arm, inverse parallel respectively thyristor Q1, Q2 and diode D1, D2 have been connected and first and second switching circuits that form, so that the mode of diode D1, the mutual reversed polarity of D2 is connected in series and forms.About the second switch arm, form by the capacitor C1 that is connected in series on the 3rd switching circuit that connects thyristor Q3 and diode D3 formation in inverse parallel.
Rectifier arm and first and the second switch arm is parallel with one another is connected.Form switching circuit 10 by first and second switch arms.Between the tie point of switch element Q1, the Q2 of the tie point of the diode D11 of rectifier arm and diode D12 and first switch arm, connected AC power AC via inductor L1.
In addition, on first switch arm, the be connected in parallel primary winding of inductor L2 and transformer T1 and the series circuit of capacitor C2.In addition, inductor L2 also can utilize the leakage inductance of transformer T1.Secondary coil N2 is set in transformer T1.Secondary coil N2 makes by the voltage after the diode D5 rectification level and smooth by capacitor C3, then to load RL output dc voltage.Also can be replaced into the circuit of synchronous rectification that has used MOSFET to diode D5.
The control circuit that each switch element Q1 of control switch circuit 10～Q3 conducting is turn-offed has the output voltage detecting circuit 72 of the terminal voltage that detects capacitor C3; Obtain output voltage error, then with the comparison amplifier 77 of its amplification by output voltage detecting circuit 72 detected output voltage detected values and output voltage command value; Compare output voltage error and PWM carrier wave, generate the first pwm signal generative circuit 96 of pwm signal.
In addition, the input voltage detection circuit 71 that has the input voltage that detects AC power AC; With the current sensor 73 and the input current testing circuit 74 that detect input current.Input voltage detection circuit 71 detects the alternating voltage of AC power AC, inputs to absolute value circuit 91 then.Absolute value circuit 91 is obtained the absolute value of alternating voltage detected value, inputs to multiplier 78 then.Current sensor 73 detects the input current that flows through AC power AC, inputs to input current testing circuit 74 then.Input current testing circuit 74 is to absolute value circuit 92 input input currents.Absolute value circuit 92 is obtained the absolute value of input current detected value, inputs to amplifier 79 then.Positive and negative judging circuit 76 is output as the signal that " H " exported in timing at input voltage detection circuit 71, the signal of output " L " when being negative.
The control system of the drive signal of each switch element Q1～Q3 of the generation of present embodiment has output voltage control system 95 and power-factor improvement control system 90.Output voltage control system 95 has the first pwm signal generative circuit, and output voltage error and PWM carrier wave that it is relatively obtained by comparison amplifier 77 generate pwm signal.On the other hand, power-factor improvement control system 90 has multiplier 78, and its output voltage error to relatively amplifier 77 outputs multiply by from the absolute value of the alternating voltage detected value of absolute value circuit 91 outputs.The output of multiplier 78 is transfused to comparison amplifier 79 as the input current command value.The input current command value that comparison amplifier 79 is relatively imported and from the absolute value of the input current detected value of absolute value circuit 92 output is obtained the input current error and is amplified.Be transfused to maximum value circuit 93 from the input current error of comparison amplifier 79 outputs.The output voltage error that maximum value circuit 93 is relatively exported from comparison amplifier 77 from the input current sum of errors of comparison amplifier 79 outputs inputs to the second pwm signal generative circuit 94 with a big side.Pwm signal generative circuit 94 relatively from the output voltage error or the input current sum of errors PWM carrier wave of maximum value circuit 93 outputs, generates pwm signal.
The pwm signal that is generated by pwm signal generative circuit 94 and pwm signal generative circuit 96 is transfused to respectively to drive signal generation circuit 97.Drive signal generation circuit 97 is made of a plurality of gates, generates drive signal Q1～Q3-Duty of each switch element Q1～Q3 according to the pwm signal from 94,96 inputs of pwm signal generative circuit.Promptly, with polarity of voltage from the AC power AC of positive and negative judging circuit 76 outputs be just " H " half period and for the half period of bearing " L " consistent, generate drive signal, this drive signal is turn-offed the switch element Q1 of first switch arm, Q2 conducting, when at least one side in switch element Q1, Q2 turn-offs, make the switch element Q3 conducting of second switch arm.
The following describes the action of the embodiment 3 of formation like this.In embodiment 1, can't separate the switch element that the power controlling factor improves control and output voltage control respectively.Therefore, have following problem: when power-factor improvement is controlled when preferential, it is big that the change of output voltage becomes; When output voltage is controlled when preferential, the input current waveform distortion can't obtain sinuous waveform.That is the action waveforms when, Fig. 6 represents the control circuit of Application Example 1 in the present embodiment.In the figure, with the voltage of V (AC) expression AC power AC, with I (AC) expression input current, with V (C3) expression output voltage, with the voltage of V (77) expression amplifier 77, with the voltage of V (79) expression amplifier 79.In the drawings, arrow represent during, for the V (77) as the margin of error of output voltage, the increase and decrease of the margin of error V of input current waveform (79) relation is inconsistent.That is, because power-factor improvement control and output voltage control can't get both, so result's input current I (AC) distortion as can be known, the change of output voltage V (C3) also becomes big.
Therefore, in the present embodiment, be timing at the polarity of voltage of AC power AC, switch element Q1 is controlled as input current waveform, i.e. the major component of power-factor improvement control makes the major component of switch element Q2 as output voltage control.Therefore, the function that input current waveform control and output voltage control that can get both.In addition, when negative, can satisfy performance equally at the polarity of voltage of AC power AC for the effect of alternation switch element Q1 and Q2.
Specifically, in the present embodiment, be with the difference of embodiment 1, as power-factor improvement control system 90 the peaked maximum value circuit 93 of output comparison amplifiers 77 and comparison amplifier 79 is arranged on the leading portion of pwm signal generative circuit 94, and the pwm signal generative circuit 96 that generates pwm signal according to the output of comparison amplifier 77 is set as output voltage control system 95.
Pwm signal generative circuit 94,96 is according to the synchronous output pwm signal of synchronizing signal difference.Drive signal generation circuit 97 generates the drive signal from Q1 to Q3 according to the output of pwm signal generative circuit 94,96 and positive and negative judging circuit 76.In the present embodiment, make output voltage control system 95 have precedence over power-factor improvement control system 90 and come control switch element Q1 and Q2, construct the system that carries out power-factor improvement control in its outside.
Fig. 7 is the action waveforms that compares the present embodiment of expression with Fig. 6, with the voltage of V (AC) expression AC power AC, with I (AC) expression input current, with V (C3) expression output voltage, with the voltage of V (77) expression amplifier 77, with the voltage of V (79) expression amplifier 79.In the drawings, because make the V (77) as output voltage error preferentially come control switch element Q1, Q2, so output voltage V (C3) is stable, the result obtains the also repressed waveform of distortion of input current I (AC).
Fig. 8 represents that the polarity of voltage of AC power AC is drive signal and the electric current of element current and inductor L1, L2 and the current waveform of secondary side rectifier diode D5 of each switch element of timing.When switch element Q1 and Q2 are conducting state, in the path of AC-L1-D11-Q1, flow through the electric current of stored energy in inductor L1, and the electric current that in the path of C2-N1-L2-Q1-Q2, flows through stored energy in transformer T2 by the stored charge of capacitor C2.
Present embodiment as mentioned above, the major component of switch element Q1, the major component of switch element Q2 as output voltage control as input current waveform control.Therefore, be later than under the condition of the timing that Q2 turn-offs power-factor improvement control and output voltage control establishment in the timing that Q1 turn-offs.That is, control output voltage when Q1 and Q2 are all conducting state, control input current waveform when the state that Q1 conducting Q2 turn-offs.When Q2 turn-offed, the stored energy by inductor L2 flow through back flow current in the path of L2-D3-C1-C2-N1.During this period when the Q3 conducting time, because back flow current flows through on the path of L2-Q3-C1-C2-N1, so Q3 becomes the synchronous rectification action, if use high withstand voltage but MOSFET that superstructure that conducting resistance is little is made, then conducting loss diminishes.Because Q3 is a conducting state at D3, promptly element voltage is conducting under the state of zero volt, so become the ZVS action, the conducting loss does not take place.
On the other hand, at the stored energy of secondary side by transformer T1 in the upper reaches, path of N2-D5-C3 overcurrent, by the flyback action to the outlet side supply capability.The stored energy of L2 becomes when zero before Q1 turn-offs, and the stored charge by capacitor C1 flows through electric current in the path of C1-Q3-L2-N1-C2.When Q1 turn-offed, by the stored energy of inductor L1, the electric current of L1 continued to flow then, but because inductor L2 hinders current path, so in the path of L1-D11-Q3-C1-D2-AC, flow through electric current.When the electric current of inductor L2 reached the electric current of inductor L1, the stored energy by L1 was in the path of AC-L1-D11-L2-N1-C2-D2 relaying afterflow overcurrent.
On the other hand, in DC-DC transducer one side, the stored charge by capacitor C1 flows through electric current in the path of C1-Q3-L2-N1-C2.Then, the stored energy by L2 flows through electric current in the path of L2-N1-C2-D2-D1 when Q3 turn-offs.Can realize the ZVS action in this period by making Q1, Q2 conducting.
As shown in Figure 9, regularly synchronously make the Q2 conducting, also can make Q2 synchronous rectification by shutoff with Q1.When the stored energy of L2 becomes zero, return the pattern of stored energy in above-mentioned L1, T1, during the polarity of voltage of AC is positive, repeat this action later on.At the polarity of voltage of AC when negative, switch element Q1 and Q2 interchange reaction.So, in the continuous current mode of the electric current continuous flow of L1, by utilizing the stored energy of inductor L2, can be with ZVS action drives switch element Q1 to Q3.
As mentioned above, identical according to present embodiment with embodiment 1, while can carry out power-factor improvement under the pattern of continuous input current and control output power making, and can reduce the switching losses relevant with power conversions.
Especially, according to present embodiment, by error according to the big side of input current sum of errors output voltage error, the conducting of control thyristor Q1 (or Q2) is turn-offed, and control by making the output voltage control system have precedence over the power-factor improvement control system, can make output voltage stabilization, the result can also suppress the distortion of input current waveform.
[embodiment 4]
Figure 10 represents to use the circuit structure diagram of the embodiment 4 of power inverter second mode of the present invention.Give identical symbol and omit explanation for the part identical with Fig. 5.In Figure 10, be with the difference of embodiment 3, the series circuit of the series circuit of switch element Q3 and capacitor C1 and inductor L2 and primary winding N1 is connected in parallel.Action and embodiment 3 are identical substantially, but difference is that the back flow current of inductor L1 flows via capacitor C2, and capacitor C2 is not in the electric current of the inductor L2 path mobile via Q3 or D3.
The structure of present embodiment also can be used in embodiment 1.
[embodiment 5]
Figure 11 represents to use the circuit structure diagram of the embodiment 5 of power inverter second mode of the present invention.As shown in figure 11, present embodiment alternating electromotive force is converted on the alternating electromotive force this point different with embodiment 3.Give identical symbol and omit explanation for the part identical with Fig. 5.
Present embodiment is to flow through high-frequency ac current in load coil Lr, the heating object of metal is carried out the example of the power inverter of electromagnetic induction heating.Though heating object is not shown, with load coil Lr magnetic coupling.
As shown in the figure, the output circuit of present embodiment is made of the series circuit of the second capacitor C2 and load coil Lr.And, detect the output current that flows through load coil Lr by current sensor 80 and output current detection circuit 81, in comparison amplifier 77, obtain with the error of output current instruction and amplify,, switch element Q1～Q3 is carried out switch control in order to reduce this error.
Therefore,, can access the effect identical, in addition, can be controlled to be command value to the output current that load coil Lr supplies with embodiment 3 according to present embodiment.Give identical symbol and omit explanation for the part identical with Fig. 5.Action is identical with the action of the primary side of embodiment 3, omits explanation.
The present invention can be used as and uses being used for household electrical appliances, people's livelihood equipment or the professional AC power insulation type ac-dc as input, perhaps can be used as general family and professional fusion of going up the induction heating cooking instrument that uses, warm water generations, low temperature high-temperature vapor generation device, metal, photocopier toner fixing and uses with the hot power supply that duplicates the thermal source in a plurality of fields such as cylinder.
Claims (8)
1. a power inverter is characterized in that,
Have: rectifier arm, with first diode and second diode along polarity be connected in series and form;
First switch arm connects thyristor and diode to inverse parallel and first and second switching circuits that form, so that the mode of the mutual reversed polarity of described diode is connected in series and forms;
The second switch arm is in that inverse parallel is connected and is connected in series first capacitor on the 3rd switching circuit that forms and forms with diode with thyristor; And
Output circuit, it has the series circuit of second capacitor and second inductor,
The described rectifier arm and first switch arm are connected in parallel,
The tie point of first diode of described rectifier arm and second diode, and the tie point of first and second switching circuits of first switch arm between, connect AC power via first inductor,
The series circuit of second capacitor and second inductor and described rectifier arm and first switch arm are connected in parallel,
Second switch arm and described rectifier arm and first switch arm are connected in parallel, and perhaps second inductor with described output circuit is connected in parallel.
2. power inverter according to claim 1 is characterized in that,
Also have control circuit, its conducting to described each thyristor is turn-offed and is controlled,
Described control circuit has: output control system, and it turn-offs the thyristor conducting of first and second switching circuits according to the output order value of described output circuit and the output voltage error of output detected value; And power-factor improvement control system, the input current command value that it generates according to the voltage detecting value that described output voltage error be multiply by described AC power and from the bigger side's of the input current error of the input current detected value of described AC power and described output voltage error error, the thyristor conducting of first and second switching circuits is turn-offed
At least one side of the thyristor of first and second switching circuits turn-off during, make the thyristor conducting of the 3rd switching circuit.
3. power inverter according to claim 1 is characterized in that,
Described output circuit comprises: the series circuit of second capacitor and second inductor, and this second inductor comprises the primary winding of transformer at least; And the rectification circuit that is connected with the secondary coil of described transformer,
Output is carried out direct current after the rectification by this rectification circuit.
4. power inverter according to claim 3 is characterized in that,
Described transformer has two secondary coils,
Described rectification circuit has: two rectification circuits, and they carry out rectification to the voltage of described two secondary coils respectively; With the 3rd capacitor, it is used to make the output voltage of these two rectification circuits level and smooth,
The terminal voltage of the 3rd capacitor is exported as direct current.
5. power inverter according to claim 2 is characterized in that,
Described control circuit has: output voltage detecting circuit is used to detect the output voltage of described output circuit;
First comparing unit is used to obtain the output voltage error by detected output voltage of this output voltage detecting circuit and output voltage command value;
The first pwm signal generative circuit is used for more described output voltage error and the PWM carrier wave generates pwm signal;
Input voltage detection circuit is used to detect the input voltage of described AC power;
The input current testing circuit is used to detect input current;
The input current command unit is used for generating the input current command value according to described output voltage error;
Second comparing unit is used to obtain the input current error of this input current command value and the detected input current detected value of described input current testing circuit;
The second pwm signal generative circuit is used for more described input current sum of errors PWM carrier wave and generates pwm signal; And
Drive signal generation circuit, it is according to the pwm signal from the output of the first pwm signal generative circuit, the drive signal that generation is turn-offed the thyristor conducting of second switch circuit, and generate the drive signal of the thyristor conducting shutoff that makes first switching circuit according to pwm signal from the output of the second pwm signal generative circuit, and at least one side who is created on the thyristor of first and second switching circuits be turned off during, make the drive signal of the thyristor conducting of the 3rd switching circuit.
6. power inverter according to claim 1 is characterized in that,
Described output circuit is the series circuit of second capacitor and second inductor that comprises load coil at least, and output stream is crossed the alternating current of described load coil.
7. power inverter according to claim 6 is characterized in that,
Described control circuit has: output current detection circuit is used to detect the output current of described output circuit;
First comparing unit is used to obtain the error by detected output current of this output current detection circuit and output current command value;
The first pwm signal generative circuit, the output and the PWM carrier wave that are used for comparison first comparing unit generate pwm signal;
Input voltage detection circuit is used to detect the input voltage of described AC power;
The input current testing circuit is used to detect input current;
The input current command unit is used for generating the input current command value according to the output by the detected input voltage detected value of described input voltage detection circuit and first comparing unit;
Second comparing unit is used to obtain this input current command value and by the error of the detected input current detected value of described input current testing circuit;
The second pwm signal generative circuit, it compares according to a bigger side's of the described output voltage error of described input current sum of errors error and PWM carrier wave and generates pwm signal; And
Drive signal generation circuit, it is according to the pwm signal from the output of the first pwm signal generative circuit, the drive signal that generation is turn-offed the thyristor conducting of second switch circuit, and generate the drive signal of the thyristor conducting shutoff that makes first switching circuit according to pwm signal from the output of the second pwm signal generative circuit, and at least one side who is created on the thyristor of first and second switching circuits be turned off during, make the drive signal of the thyristor conducting of the 3rd switching circuit.
8. power inverter is characterized in that having:
First and the second switch arm, wherein first switch arm respectively inverse parallel connect and to have first and second thyristor of reverse withstand voltage function and form, second switch arm inverse parallel respectively connects and has the 3rd and the 4th thyristor of reverse withstand voltage function and form;
First inductor, it in series inserts in the circuit that first switch arm and AC power are connected in parallel;
First capacitor, it in series inserts in the circuit that second switch arm and first switch arm are connected in parallel; With
Output circuit, its have with first switch arm and second switch arm in second capacitor that is connected in parallel of a certain side and the series circuit of second inductor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007129709A JP4961258B2 (en) | 2007-05-15 | 2007-05-15 | Power converter |
| JP2007-129709 | 2007-05-15 |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008101078258A Division CN101309047B (en) | 2007-05-15 | 2008-05-14 | Electric power conversion device |
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| CN101888174A true CN101888174A (en) | 2010-11-17 |
| CN101888174B CN101888174B (en) | 2013-07-24 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2008101078258A Expired - Fee Related CN101309047B (en) | 2007-05-15 | 2008-05-14 | Electric power conversion device |
| CN2010102435917A Expired - Fee Related CN101888174B (en) | 2007-05-15 | 2008-05-14 | Power conversion device |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2008101078258A Expired - Fee Related CN101309047B (en) | 2007-05-15 | 2008-05-14 | Electric power conversion device |
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| JP (1) | JP4961258B2 (en) |
| CN (2) | CN101309047B (en) |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5640464B2 (en) | 2009-07-29 | 2014-12-17 | Tdk株式会社 | Switching power supply |
| JP2011078271A (en) * | 2009-10-01 | 2011-04-14 | Mitsubishi Electric Corp | Power converter |
| JP5857212B2 (en) * | 2010-09-15 | 2016-02-10 | パナソニックＩｐマネジメント株式会社 | DC / DC converter |
| JP5601965B2 (en) | 2010-10-20 | 2014-10-08 | 東芝テック株式会社 | Power converter |
| JP5507416B2 (en) * | 2010-11-04 | 2014-05-28 | 新電元工業株式会社 | Power supply |
| JP5909666B2 (en) | 2011-07-04 | 2016-04-27 | パナソニックＩｐマネジメント株式会社 | Switching power supply |
| JP5476400B2 (en) | 2012-01-30 | 2014-04-23 | 株式会社日立製作所 | Power conversion device, power conversion device control method, and hard disk device |
| TWI433442B (en) * | 2012-02-20 | 2014-04-01 | Global Unichip Corp | Buck converter |
| JP5734356B2 (en) * | 2013-07-08 | 2015-06-17 | 三菱電機株式会社 | Power converter |
| EP2933646B1 (en) * | 2014-04-17 | 2019-04-17 | Siemens Aktiengesellschaft | Precision measurement of voltage drop across a semiconductor switching element |
| EP3125065B1 (en) * | 2015-07-31 | 2018-12-19 | Power Integrations Switzerland GmbH | Communicating across galvanic isolation |
| CN105529808A (en) * | 2015-12-25 | 2016-04-27 | 青岛海特新蓝生物科技有限公司 | All-weather power generation station |
| CN105471071A (en) * | 2015-12-25 | 2016-04-06 | 青岛朝阳华泰管理咨询服务有限公司 | All-weather power station |
| EP3484033B1 (en) * | 2017-11-14 | 2023-06-07 | Delta Electronics (Thailand) Public Co., Ltd. | Current measurement circuit |
| JP7258614B2 (en) * | 2019-03-20 | 2023-04-17 | 東芝テック株式会社 | power converter |
| JP7080398B2 (en) * | 2019-05-20 | 2022-06-03 | 三菱電機株式会社 | Power supply |
| WO2022011646A1 (en) * | 2020-07-16 | 2022-01-20 | 深圳市骁阳工程咨询有限公司 | Constant-power power supply apparatus and sunlight simulation device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5384248A (en) * | 1976-12-29 | 1978-07-25 | Matsushita Electric Ind Co Ltd | Induction heating device |
| JP2632586B2 (en) * | 1990-04-24 | 1997-07-23 | サンケン電気株式会社 | Container with lid |
| JP2867069B2 (en) * | 1990-06-12 | 1999-03-08 | 新電元工業株式会社 | Switching power supply |
| CN1109399C (en) * | 2000-10-19 | 2003-05-21 | 南京航空航天大学 | Three-level Dc converter of zero-voltage switch with clamping diode |
| JP4765015B2 (en) * | 2001-07-06 | 2011-09-07 | 富士電機株式会社 | Power converter |
| JP2003338358A (en) * | 2002-05-20 | 2003-11-28 | Matsushita Electric Ind Co Ltd | Induction heating apparatus and induction heating cooking device and rice cooker by use of the same |
| US6771521B1 (en) * | 2003-02-20 | 2004-08-03 | Delta Electronics, Inc. | Active snubber for synchronous rectifier |
-
2007
- 2007-05-15 JP JP2007129709A patent/JP4961258B2/en not_active Expired - Fee Related
-
2008
- 2008-05-14 CN CN2008101078258A patent/CN101309047B/en not_active Expired - Fee Related
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| Publication number | Publication date |
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| CN101309047B (en) | 2012-03-28 |
| JP2008289228A (en) | 2008-11-27 |
| CN101888174B (en) | 2013-07-24 |
| CN101309047A (en) | 2008-11-19 |
| JP4961258B2 (en) | 2012-06-27 |
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