Utility model content
The purpose of the utility model is to provide a kind of Switching Power Supplies of output ripple suppression circuit topological structure, by split
The output in powered-down source increases level-one filtering topology, carries out on the basis of original traditional LC is filtered to the output of Switching Power Supply
Secondary filtering reduces output ripple, and realizes the accurate voltage regulation filtering control to power supply by two-step evolution.
Realizing the technical solution of above-mentioned purpose is: a kind of Switching Power Supply of output ripple suppression circuit topological structure, including
Power circuit and the output circuit for being connected to power circuit output end, it is characterised in that: the Switching Power Supply further includes filtering
Device, the first control loop, the second control loop, the filter are connected between power circuit and output circuit, and described first
The input terminal of control loop is connect with output circuit, output end and filter connect, and the first control loop is for acquiring output electricity
The voltage on road is simultaneously compared with setting value, and obtained error amount controls the stationary value of filter as benchmark;For acquiring
The voltage at filter both ends is compared with setting value the output voltage of controlling power circuit as benchmark.
Further, the power circuit includes transformer T, and the input terminal of transformer T is connected with full-bridge circuit, transformer
The output end of T is connected with rectifier bridge, and the output end of rectifier bridge is connected with filter circuit.
Further, the full-bridge circuit is made of four metal-oxide-semiconductors or IGBT module connection, and the rectifier bridge is by four two
Pole pipe connection composition, the filter circuit include inductance L and capacitor C, and one end of inductance L connects with the anode in rectification bridge output end
It connects, the positive terminal of the other end connection capacitor C of inductance L, the cathode of the negative pole end connection rectification bridge output end of capacitor C.
Further, the filter includes driving triode Q and multiple output power triode Q1...Qn,
Driving is connected with each other with the collector c of triode Q and output power triode Q1...Qn and is labeled as A point, A point and electricity
Hold the positive terminal connection of C, output power is serially connected with resistance R10 with the emitter e of triode Q1...Qn respectively, and resistance R10's is another
One end is connected with each other and is labeled as B point, and the driving is connect with collector c and the A point of triode Q, and driving is with triode Q's
Emitter e is connect with output power with the base stage b of triode Q1...Qn respectively.
Further, the output circuit includes load R, loads B point, the other end connection of one end connection filter of R
The cathode of capacitor C is simultaneously labeled as G point, G point ground connection.
Further, the resistance R resistance value of the emitter e concatenation of the triode Q2 is equal.
Further, first control loop includes resistance R1, R2, R3, R4, R5, R6, R7, capacitor C1, C2, operation
The B point of one end connection filter of amplifier U1, diode D10, the R1, the other end of R1 connect resistance R2, resistance R2's
Other end ground connection, one end of resistance R4 is connected between resistance R1 and R2, the other end connects the anti-phase input of operational amplifier U1B
End, the inverting input terminal of the operational amplifier U1B are also connected with resistance R3, and the other end of resistance R3 is for input reference electricity
Pressure, the non-inverting input terminal of one end connection connection operational amplifier U1B of resistance R5, other end ground connection, capacitor C1 are connected in parallel on operation
Between the inverting input terminal and output end of amplifier U1B;
The cathode of the output end connection diode D10 of operational amplifier U1B, the anode connection resistance R7 of diode D10, electricity
The driving for hindering the other end connection filter of R7 connects the direct current of 12V with one end of the base stage b, the resistance R6 of triode Q
Source, the other end connect the anode of diode D10, the anode of one end connection diode D10 of capacitor C2, other end ground connection.
Further, second control loop includes Hall voltage sensor, analog-digital converter, MCU controller, duty
Than adjusting circuit, driving circuit, the A point and B point of the signal acquisition terminal connection filter of the Hall voltage sensor, Hall electricity
The signal output end of pressure sensor connects MCU controller by analog-digital converter, and the output end of MCU controller is connected with duty ratio
Circuit is adjusted, the output end of duty ratio adjusting circuit connects four metal-oxide-semiconductors or IGBT module of full-bridge circuit by driving circuit
Control terminal.
The utility model has the beneficial effects that
The utility model increases level-one filter circuit by the output to Switching Power Supply, and carries out to filter circuit part equal
Stream realizes the inhibition to the stability contorting and ripple of output voltage by two-step evolution loop.
The resistance R resistance value of the emitter e concatenation of the triode Q2 of the utility model is equal, realizes the stream of triode Q2
Press.
Specific embodiment
As described in Fig. 1,2, the utility model include power circuit 1, filter 2, output circuit 3, the first control loop 4,
Second control loop 5, filter 1 are connected between power circuit 1 and output circuit 3.
Power circuit 1 includes transformer T, and the input terminal of transformer T is connected with full-bridge circuit 6, the input terminal of full-bridge circuit 6
Input power Uin is connected, the output end of transformer T is connected with rectifier bridge 7, and the output end of rectifier bridge 7 is connected with filter circuit 8.
Full-bridge circuit 6 include first switch S1, second switch S2, third switch S3 and the 4th switch S4, first switch S1,
Second switch S2, third switch S3 and the 4th switch S4 can use metal-oxide-semiconductor or IGBT module, input power Uin anode with
One end of first switch S1 is connected with one end of third switch S3, the other end of first switch S1 and the one of second switch S2
End is connected, and the other end of third switch S3 is connected with one end of the 4th switch S4, and the other end of second switch S2 and the 4th is opened
The other end for closing S4 is connect with the cathode of input power Uin;Rectifier bridge 7 includes capacitor D1, D2, D3, D4, capacitor D1, D3's
Negative pole end is connected, and the positive terminal of capacitor D1 connects capacitor D2, and the positive terminal of capacitor D3 connects capacitor D4, and capacitor D2, capacitor D4 are just
It is extreme to be connected with each other;Filter circuit 8 includes inductance L and capacitor C, and one end of inductance L is connect with the anode in rectification bridge output end,
The positive terminal of the other end connection capacitor C of inductance L, the cathode of negative pole end connection 7 output end of rectifier bridge of capacitor C.
One end of transformer T first winding is connected between first switch S1, second switch S2, the other end is connected to third
Between switch S3 and the 4th switch S4, one end of transformer T secondary winding is connected between capacitor D1, D2, the other end is connected to
Between capacitor D3, D4.
Filter 2 includes driving triode Q and multiple output powers triode Q1...Qn, the present embodiment setting
There are two respectively Q1, Q2, driving triode Q, output power be connected with each other with the collector c of triode Q1...Qn, simultaneously
Labeled as A point, A point is connect with the positive terminal of capacitor C, and driving is serially connected with resistance R10, triode with the emitter e of triode Q1
The emitter e of Q2 is serially connected with resistance R11, and the other end of resistance R10, R11 are connected with each other and are labeled as B point, described to drive with three
Collector c and the A point of pole pipe Q is connect, the driving emitter e of the triode Q base with output power triode Q1, Q2 respectively
Pole b connection.
Output circuit 3 include load R, load R one end connection filter B point, the other end connection capacitor C cathode,
And it is labeled as G point, G point ground connection.
First control loop 4 includes resistance R1, R2, R3, R4, R5, R6, R7, capacitor C1, C2, operational amplifier U1, two poles
The B point of one end connection filter of pipe D10, R1, the other end of R1 connect resistance R2, the other end ground connection of resistance R2, resistance R4
One end be connected between resistance R1 and R2, the other end connection operational amplifier U1B inverting input terminal, the operational amplifier
The inverting input terminal of U1B is also connected with resistance R3, and the other end of resistance R3 is used for input reference voltage, and one end of resistance R5 connects
The non-inverting input terminal of operational amplifier U1B, other end ground connection, capacitor C1 be connected in parallel on operational amplifier U1B inverting input terminal and
Between output end;
The cathode of the output end connection diode D10 of operational amplifier U1B, the anode connection resistance R7 of diode D10, electricity
The driving for hindering the other end connection filter of R7 connects the direct current of 12V with one end of the base stage b, the resistance R6 of triode Q
Source, the other end connect the anode of diode D10, the anode of one end connection diode D10 of capacitor C2, other end ground connection.
Second control loop 5 includes Hall voltage sensor 5.1, analog-digital converter 5.2, MCU controller 5.3, duty ratio
Adjust circuit 5.4, the driving circuit for driving first switch S1, second switch S2, third switch S3 and the 4th switch S4
5.5, the A point and B point of the signal acquisition terminal connection filter 2 of Hall voltage sensor 5.1, the letter of Hall voltage sensor 5.1
Number output end connects MCU controller 5.3 by analog-digital converter 5.2, and the output end of MCU controller 5.3 is connected with duty ratio tune
Economize on electricity road 5.4, the output end of duty ratio adjusting circuit 5.4 pass through four metal-oxide-semiconductors or IGBT that driving circuit connects full-bridge circuit 6
The control terminal of module.
Working principle of the utility model is:
First control loop 4 first samples the voltage UB of the B point of filter 2, and the first control loop 4 is integral
Control circuit, when output voltage UB is reduced, driving is declined with the base stage b current potential of triode Q, the base stage b electric current of triode Q
Decline, output power are declined with the base stage b electric current of triode Q1, Q2, due to the presence of resistance R7, so that driving triode Q,
Output power is in amplification workspace with triode Q1, Q2, then output power triode Q1, Q2 both end voltage (being calculated as UAB)
Decline.
The control of power circuit 1 is sampled as UAB, when UAB decline, then can enter the second control loop 5, the second control loop
5 are isolated sampling to UAB voltage by Hall voltage sensor 5.1, and sampled signal is sent to analog-digital converter 5.2, and simulation is believed
Number digital signal is converted to, obtains digital signal and send to MCU controller 5.3, MCU controller 5.3 uses model
The chip of TMS320F28335, the progress operation of MCU controller 5.3 obtain duty cycle signals and pass through duty ratio adjusting circuit 5.4 again
Duty ratio up-regulation is controlled, the output voltage of power circuit 1 is improved, because between the A point of filter 2 and the G point of output circuit 3
Voltage (being calculated as UAG) UAG=UB+UAB, output power is declined with triode Q1, Q2 both end voltage UAB, then on output voltage UB
It rises, maintains output voltage in target value.
When output voltage UB rises, analysis, the first control loop 4 and the second control loop 5 realize electricity
The two-stage stability contorting on road.
If the B point voltage waveform and the voltage waveform of A point of filter 2 are consistent, Zhi Nengtong without filter 2
Filter circuit 8 is once filtered, and is increased filter 2, is used by the first control loop 4 to output voltage UB waveform,
The control voltage of driving triode Q base stage b is obtained, capacitor C2 is filtered driving with the voltage of the base stage b of triode Q,
Voltage waveform of the output power with the base stage b of the base stage b voltage follow driving triode Q of triode Q1, Q2 at this time, output work
Rate determines that the B point voltage waveform of filter 2, B point voltage waveform are also output with the voltage waveform of triode Q1, Q2 base stage b
Waveform has carried out secondary filtering to output voltage.
Resistance R10 and R11 are set as the identical resistance of two resistance values, because Q1 connects with R10, Q2 connects with R11, string
The voltage at both ends is equal after connection, as UAB, and because output power is equal with the voltage of the base stage b of triode Q1, Q2, then flows
Cross resistance R10, the electric current of R11 be it is equal, then output power is equal, resistance with the voltage at the both ends triode Q1, Q2
The presence of R10, R11 ensure that the both end voltage of output power triode Q1, Q2 are equal equal with electric current.
Resistance R7 is connected with triode Q with driving and is amplified to driving with the base current of triode Q, drives three poles
Pipe Q emitter is connected with output power with the base stage of triode Q1, Q2, and providing enough electric currents ensures output power triode
Q1 and Q2 are in amplification region.Output power is in parallel after being connected respectively with triode Q1, Q2 with resistance R11, R12, provides bigger electricity
Stream, the present invention is indefinite with the number of triode parallel connection using output power, increases number of parallel according to output current conditions.