The content of the invention
The purpose of the embodiment of the present invention is to provide a kind of output voltage and frequency inspection for high-performance vector frequency converter
Slowdown monitoring circuit, technical problem to be solved is:By optimization, it is designed to a kind of circuit and had both met residual voltage detection, can realizes again
The multinomial detection circuit of output voltage and frequency detecting, and high reliability Curve guide impeller is carried out for details, to meet common height
The demand of the residual voltage detection of capability vector control frequency converter.
The embodiment of the present invention is achieved in that a kind of output voltage and frequency detecting for high-performance vector frequency converter
Circuit, the detection circuit includes:Differential amplifier circuit module, reversely the scaling circuit module with addition function, amplification
Circuit module and comparator module;
The differential amplifier circuit module includes the first operational amplifier and its peripheral circuit, first operational amplifier
Two inputs connect two-phase in the three-phase output voltage of frequency converter respectively, output end connects the ratio with addition function
Example amplification circuit module;
The scaling circuit module with addition function includes the second operational amplifier and its peripheral circuit, described the
The inverting input of two operational amplifiers connects the output end of the differential amplifier circuit module, normal phase input end connection+2.5V
Voltage, output end connection the amplifier circuit module and the comparator module;
The reverse amplification circuit module includes the 3rd operational amplifier and its peripheral circuit, the 3rd operational amplifier
Inverting input connect the output end of the scaling circuit module with addition function, positive input end grounding, output
The output voltage of the end output frequency converter;
The comparator module includes comparator and its peripheral circuit, and the normal phase input end of the comparator connects the band
The output end of the scaling circuit module of addition function, inverting input is defeated by connecting+2.5V voltages, output end after resistance
Go out the output frequency signal of the frequency converter.
The first of a kind of output voltage and frequency detection circuit for high-performance vector frequency converter that the present invention is provided is excellent
In selecting embodiment:The peripheral circuit of the first operational amplifier U6A includes:
Input resistance R41, resistance R43 and R49, clamper protection diode D7 and D9, go DM EMI electric capacity C25, feedback
Resistance R53, power filter decoupling capacitor C23 and C28 and output current limiting protective resistance R46;
Described input resistance R41 one end connects+2.5V voltages, and the other end is connecting the first operational amplifier U6A just
Phase input;
The resistance R43 and R49 is mega-ohms resistance, and described resistance R43 one end connects the output voltage of the frequency converter
W phases, the other end connects the normal phase input end of the first operational amplifier U6A;Described resistance R49 one end connects the frequency conversion
The U phases of the output voltage of device, the other end connects the inverting input of the first operational amplifier U6A;
Clamper the protection diode D7 and D9 connect the normal phase input end of the first operational amplifier U6A and anti-respectively
Phase input;
The normal phase input end for going to DM EMI electric capacity C25 two ends to connect the first operational amplifier U6A respectively and
Inverting input;
The feedback resistance R53 two ends connect the inverting input and output end of the first operational amplifier U6A respectively;
Power filter decoupling capacitor C23 one end ground connection, the other end connects the positive electricity of the first operational amplifier U6A
Source, the power filter decoupling capacitor C23 is also associated with the tie point of the positive power source terminal of the first operational amplifier U6A
+ 15V voltages;Power filter decoupling capacitor C28 one end ground connection, the other end connects the negative of the first operational amplifier U6A
Power end, the power filter decoupling capacitor C28 is also connected with the tie point of the negative power end of the first operational amplifier U6A
There are -15V voltages;
The output current limiting protective resistance R46 is connected to the output end and the feedback of the first operational amplifier U6A
Between resistance R53.
The second of a kind of output voltage and frequency detection circuit for high-performance vector frequency converter that the present invention is provided is excellent
In selecting embodiment:The peripheral circuit of the second operational amplifier U6B includes:
Input build-out resistor R40, resistance R42 and R47, feedback resistance R51, remove DM EMI electric capacity C24 and output pincers
Position protection diode D8;
Described input build-out resistor R47 one end connects the differential amplifier circuit module, other end connection second fortune
Calculate the inverting input of amplifier U6B;One end connection+2.5V voltages, another after the resistance R40 and resistance R42 parallel connections
The normal phase input end of end connection the second operational amplifier U6B;
The feedback resistance R51 two ends connect the inverting input and output end of the second operational amplifier U6B respectively;
The normal phase input end for going to DM EMI electric capacity C24 two ends to connect the second operational amplifier U6B respectively and
Inverting input;
The output clamper protection diode D8 connects the output end of the second operational amplifier U6B.
The 3rd of a kind of output voltage and frequency detection circuit for high-performance vector frequency converter that the present invention is provided is excellent
In selecting embodiment:The peripheral circuit of the 3rd operational amplifier U8A includes:Input build-out resistor R54 and resistance R56, feedback
Resistance R57, filter capacitor C33, power decoupling filter capacitor C30 and C32 and output LPF resistance R55 and electric capacity C31;
Input build-out resistor R54 one end ground connection, the positive that the other end connects the 3rd operational amplifier U8A is defeated
Enter end;Described input build-out resistor R56 one end connects the scaling circuit module with addition function, other end connection institute
State the inverting input of the 3rd operational amplifier U8A;
Two ends connect the 3rd operational amplifier respectively after the feedback resistance R57 and filter capacitor C33 parallel connections
The inverting input and output end of U8A;
Power decoupling filter capacitor C30 one end ground connection, the other end connects the positive electricity of the 3rd operational amplifier U8A
Source, the power decoupling filter capacitor C30 is also associated with the tie point of the positive power source terminal of the first operational amplifier U8A
+ 15V voltages;Power decoupling filter capacitor C32 one end ground connection, the other end connects the negative of the first operational amplifier U8A
Power end, the power decoupling filter capacitor C32 is also connected with the tie point of the negative power end of the first operational amplifier U8A
There are -15V voltages;
Described output LPF resistance R55 one end connects the output end of the 3rd operational amplifier U8A, and the other end connects
Connect one end of the electric capacity C31, the other end ground connection of the electric capacity C31, the output LPF resistance R55 and the electric capacity
The tie point output of C31, obtains the output line voltage value of the frequency converter.
The 4th of a kind of output voltage and frequency detection circuit for high-performance vector frequency converter that the present invention is provided is excellent
In selecting embodiment:The peripheral circuit of the comparator U7 includes:Input resistance R45, impedance matching resistor R50 and R52, filtered electrical
Hold C29, electric capacity C26, the reliable Large Copacity resistance R39 compared with input and output bridging, export filter resistance R48 and electric capacity C27
And pull-up resistor R44;
Described input resistance R45 one end connects the scaling circuit module with addition function, other end connection institute
State the normal phase input end of comparator U7;
Described impedance matching resistor R50 one end connects+2.5V voltages, and the other end connects the anti-phase input of the comparator U7
End;
The resistance R52 latter end ground connection in parallel with the filter capacitor C29, the other end is connected by the electric capacity C26
The normal phase input end of the comparator U7;
The reliability compares the Large Copacity resistance R39 two ends bridged with input and output and is connecting the comparator U7 respectively just
Phase input and output end;
Described pull-up resistor R44 one end connects+5V voltages, and the other end connects the output end of the comparator U7;
Described output filter resistance R48 one end connects the output end of the comparator U7, and the other end connects the electric capacity C27
One end, the other end ground connection of the electric capacity C27, the tie point of the output filter resistance R48 and electric capacity C27 exports,
Obtain the output frequency of the frequency converter.
The 5th of a kind of output voltage and frequency detection circuit for high-performance vector frequency converter that the present invention is provided is excellent
In selecting embodiment:The input upper limit threshold values of the comparator U7 is
Being input into lower limit threshold values is
Wherein, Rin1It is the input resistance of the comparator, Rf1It is the feedback resistance of the comparator, VrefIt is with reference to electricity
Source ,+Vz is the power supply forward voltage for exporting the comparator, and-Vz is the power supply negative pressure for exporting the comparator.
A kind of output voltage and frequency detection circuit for high-performance vector frequency converter provided in an embodiment of the present invention
Beneficial effect includes:
A kind of output voltage and frequency detection circuit for high-performance vector frequency converter provided in an embodiment of the present invention, according to
Output voltage is detected by difference channel, that is, detects the line voltage of frequency converter two-phase output, then by isolating at the signals such as amplification
Reason front-end circuit obtains meeting the output detection signal of DSP control interface voltage ranges, while such signal is also served as down
The input of one-level hysteresis comparator, the pulse signal for finally being obtained by hysteresis comparator circuit can detect frequency converter output voltage
Frequency signal and now selection of Motor speed and direction of rotation;
Can be used to realize residual voltage detection function, according to the residual voltage frequency that the motor for detecting is produced when rotating freely,
By the output voltage of frequency converter, constant frequency boosts to the corresponding specified V/f curves magnitude of voltage of its residual voltage frequency, is then risen by normal again
Dynamic program accelerates to the new frequency of default.When the frequency converter of vector controlled usually needs shutdown to restart;Because shutting down
Afterwards because remanent magnetism is present, can be produced in the case of circumgyration incision due to the rotor circuit for closing in motor (being often referred to asynchronous motor)
Raw rotation air-gap field, so as to (frequency rotates speed with rotor in the induced voltage of the similar generator operation principle of stator side generation
Degree is directly proportional, equivalent to synchronizing speed), therefore now turned by the phase and cycle that detect stator side induced voltage
The selection speed of son and direction of rotation so that acceleration, deceleration can it is quick under the background of this known rotor selection operating mode and
Efficiently carry out, without starting from scratch, cause impact and fluctuate.It is short that the time is restarted in shutdown, and starting process is steady, will not be to negative
Carry and produce overbump, excessively stream will not be produced, be particularly suitable for capability vector control frequency conversion speed-adjusting system.
A kind of output voltage and frequency detection circuit for high-performance vector frequency converter provided in an embodiment of the present invention, also
By the parameter refinement design details and protection Anti-Interference Optimization Design of circuit, it is ensured that detection is accurate, reliable.
A kind of various detection functions of circuit realiration of the present invention, therefore can be reduced into compared to various detection circuits and functional unit
Sheet and fault rate.
Motor direction of rotation and rotary speed after halt instruction can be judged;And then be applied to without velocity control
System, can also be applied to the vector controlled such as voltage model, the arrow based on neural network estimator of output voltage detection
The control model such as amount control and the vector controlled based on fuzzy control theory.And with small volume, application cost is reduced, together
When the advantages of improve the competitiveness of product.
Specific embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, it is right below in conjunction with drawings and Examples
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
In order to illustrate technical solutions according to the invention, illustrated below by specific embodiment.
It is as shown in Figures 2 and 3 the first for providing of the invention and second output for high-performance vector frequency converter
The schematic diagram of voltage and frequency detection circuit, the detection circuit includes:Differential amplifier circuit module, the ratio with addition function
Amplification circuit module, reverse amplification circuit module and comparator module.
Differential amplifier circuit module includes the first operational amplifier and its peripheral circuit, two of first operational amplifier
Input connects the two-phase in the three-phase output voltage of frequency converter respectively, and what Fig. 2 and Fig. 3 was given respectively is the first operational amplifier
The situation of the W-U and W-V phases of the output voltage of input connection frequency converter, the scaling electricity of output end connect band addition function
Road module.
Scaling circuit module with addition function includes the second operational amplifier and its peripheral circuit, second computing
The inverting input of amplifier connects the output end of differential amplifier circuit module, normal phase input end connection+2.5V voltages, output end
Connection amplifier circuit module and comparator module.
Reverse amplification circuit module include the 3rd operational amplifier and its peripheral circuit, the 3rd operational amplifier it is anti-phase
The output end of the scaling circuit module of input connect band addition function, positive input end grounding, output end output frequency conversion
The output voltage of device.
Comparator module includes comparator and its peripheral circuit, the normal phase input end connect band addition function of the comparator
The output end of scaling circuit module, inverting input exports frequency converter by connecting+2.5V voltages, output end after resistance
Output frequency signal.
A kind of output voltage and frequency detection circuit for high-performance vector frequency converter provided in an embodiment of the present invention, it is first
First rely on difference channel to detect output voltage, that is, detect the line voltage of frequency converter two-phase output, then by isolating the letter such as amplification
Number treatment front-end circuit obtains meeting the output detection signal of DSP control interface voltage ranges, while such signal is also made
It is the input of next stage hysteresis comparator, the pulse signal for finally being obtained by hysteresis comparator circuit can detect that frequency converter is exported
The frequency signal of voltage and now selection of Motor speed and direction of rotation.
Further, by taking Fig. 2 as an example, differential amplifier circuit module with the first operational amplifier U6A be core, the first computing
The peripheral circuit of amplifier U6A includes:
Input resistance R41, resistance R43 and R49, clamper protection diode D7 and D9, go DM EMI electric capacity C25, feedback
Resistance R53, power filter decoupling capacitor C23 and C28 and output current limiting protective resistance R46.
Input resistance R41 one end connects+2.5V voltages, and the other end connects the normal phase input end of the first operational amplifier U6A.
Play impedance matching and play differential amplification (amplification coefficient here with resistance R53<1) act on, R46 resistance has been that suppression amplifier is defeated
Go out oscillation action, R41 accesses 2.5V additions reference power source to raise the output signal of input difference circuit, strengthens the anti-common of circuit
Mould interference performance strengthens the sensitivity to input signal simultaneously.
Resistance R43 and R49 are mega-ohms resistance, the W phases of the output voltage of resistance R43 one end connection frequency converter, the other end
Connect the normal phase input end of the first operational amplifier U6A, the U phases of the output voltage of resistance R49 one end connection frequency converter, the other end
Connect the inverting input of the first operational amplifier U6A.
Specifically, resistance R43 and R49 can be connected across between forceful electric power and control circuit with 6 megaohms of value, and electricity is climbed in attention
Distance, so as to according to dsp interface voltage range is more accurate and input line voltage signal of safely sampling.
Clamper protection diode D7 and D9 connect the normal phase input end and anti-phase input of the first operational amplifier U6A respectively
End.Input voltage clamper protective effect is played, limitation input current potential is in amplifier power supply voltage range, it is to avoid amplifier was because being input into
Voltage and saturation, and then ensure that circuit normal work.
DM EMI electric capacity C25 two ends are gone to connect the normal phase input end and anti-phase input of the first operational amplifier U6A respectively
End.Play DM EMI filtering between line, the effect of stabilization input voltage.
Feedback resistance R53 two ends connect the inverting input and output end of the first operational amplifier U6A respectively.
Power filter decoupling capacitor C23 one end is grounded, and the other end connects the positive power source terminal of the first operational amplifier U6A, electricity
The tie point of the positive power source terminal of source filtering decoupling capacitor C23 and the first operational amplifier U6A is also associated with+15V voltages;Power supply is filtered
Ripple decoupling capacitor C28 one end is grounded, and the other end connects the negative power end of the first operational amplifier U6A, power filter decoupling capacitor
The tie point of the negative power end of C28 and the first operational amplifier U6A is also associated with -15V voltages.
Output current limiting protective resistance R46 is connected between the output end of the first operational amplifier U6A and feedback resistance R53.
Differential amplifier circuit module in the embodiment of the present invention, the first operational amplifier that can be included according to it is anti-phase
This ratio carries out good and bad evaluation with respect to the voltage range of power supply for end or in-phase end voltage, will not in accurate derivation
Approximation is produced, more accurate detection effect is can reach, additive error will not be increased because of actual resistance error, relatively existing skill
Art is closer on the premise of same effect is reached to actually enter voltage range, while having saved cost.Differential amplifier circuit mould
Block carries out differential amplification and band current potential lifting to input terminal voltage, and the output result for obtaining can be written as formula formula (1):
In formula (1), 2.5 is 2.5V reference power sources, plays current potential lifting;Rf1It is feedback resistance (R53 as shown in Figure 2, reality
Border is desirable 100k ohm);Rin1With Rf1With dimension and unit (i.e. such as the R43 or R49 of Fig. 2, actual value 6M ohm), 60 is two
The individual actual value ratio of resistance, Uw1u1It is input difference voltage, Ua1As differential amplifier circuit module output voltage.
Scaling circuit module with addition function with the second operational amplifier U6B be core, the second operational amplifier
The peripheral circuit of U6B includes:
Input build-out resistor R40, resistance R42 and R47, feedback resistance R51, remove DM EMI electric capacity C24 and output pincers
Position protection diode D8.
Input build-out resistor R47 one end connection differential amplifier circuit module, the other end connects the second operational amplifier U6B's
Inverting input;Connection+2.5V voltages in one end after resistance R40 and resistance R42 parallel connections, the other end connects the second operational amplifier
The normal phase input end of U6B.R40, R42 and R47 be input resistance, and R40 primarily to impedance matching and choose.
Feedback resistance R51 two ends connect the inverting input and output end of the second operational amplifier U6B respectively.With input electricity
Resistance combines the amplification for carrying out input signal.
DM EMI electric capacity C24 two ends are gone to connect the normal phase input end and anti-phase input of the second operational amplifier U6B respectively
End.To stablize input signal, circuit filter action is played.
Output clamper protection diode D8 connects the output end of the second operational amplifier U6B.Enter the clamper of line output voltage
Protection.
After scaling circuit module of the output voltage of frequency converter by differential amplifier circuit module and with addition function,
Obtain basic output voltage Ub1.
Differential amplifier circuit module exports Ua1As the homophase input of the scaling circuit module with addition function, pass through
After negative-feedback circuit amplifies and be anti-phase, second level amplifier result U is obtainedb1.Scaling circuit module with addition function is by managing
Think amplifier " void is disconnected " and " empty short " characteristic, the output result that can derive the scaling circuit module with addition function is as follows
Shown in formula (2):
Wherein, Ub1For second level amplifier is exported.Wherein input resistance R40 and feedback resistance R51 takes 20k ohm, and defeated
Enter resistance R42 values identical with R47 for 10k ohm, carrying out operational amplification circuit calculating can obtain formula (2).
Reverse amplification circuit module with the 3rd operational amplifier U8A as core, the peripheral circuit of the 3rd operational amplifier U8A
Including:
Input build-out resistor R54 and resistance R56, feedback resistance R57, filter capacitor C33, power decoupling filter capacitor C30
With C32 and output LPF resistance R55 and electric capacity C31.
Input build-out resistor R54 one end ground connection, the other end connects the normal phase input end of the 3rd operational amplifier U8A;It is defeated
Enter the scaling circuit module of build-out resistor R56 one end connect band addition function, the other end connects the 3rd operational amplifier U8A
Inverting input.
Two ends connect the anti-phase input of the 3rd operational amplifier U8A respectively after feedback resistance R57 and filter capacitor C33 parallel connections
End and output end.
Power decoupling filter capacitor C30 one end is grounded, and the other end connects the positive power source terminal of the 3rd operational amplifier U8A, electricity
The tie point of the positive power source terminal of source decoupling filter capacitor C30 and the first operational amplifier U8A is also associated with+15V voltages;Power supply goes
Coupling filter capacitor C32 one end is grounded, and the other end connects the negative power end of the first operational amplifier U8A, power decoupling filter capacitor
The tie point of the negative power end of C32 and the first operational amplifier U8A is also associated with -15V voltages.
Output LPF resistance R55 one end connects the output end of the 3rd operational amplifier U8A, other end connection electric capacity
One end of C31, the other end ground connection of electric capacity C31, the tie point of output LPF resistance R55 and electric capacity C31 is exported, and obtains essence
The output line voltage value of true reliable frequency converter.
Reverse amplification circuit module facilitates direct detection frequency converter output voltage waveform when frequency converter normally runs, right
In need to use frequency converter actual output voltage and frequency control model (such as the vector controlled of voltage model, based on nerve net
The vector controlled of network estimator and the vector controlled based on fuzzy control theory) for, without redesigning output voltage in addition
Detection circuit, no matter on design cost, or is functionally all optimized what is realized, wherein bridging third level output voltage
On feedback resistance and electric capacity composition integrating circuit, play LPF and obtain the effect of sine wave, feedback resistance and electric capacity
Value can be adjusted according to actual signal.Therefore, same preposing signal process circuit in Fig. 2, realizes two kinds of functions.
Comparator module is frequency detection circuit, will obtain voltage Ub1 as the input signal of frequency detection circuit, with than
It is core compared with device U7, the peripheral circuit of comparator U7 includes:
Input resistance R45, impedance matching resistor R50 and R52, filter capacitor C29, electric capacity C26, reliability compare defeated with input
Go out the Large Copacity resistance R39 of bridging, export filter resistance R48 and electric capacity C27 and pull-up resistor R44.
The scaling circuit module of input resistance R45 one end connect band addition function, other end connection comparator U7's
Normal phase input end.
Impedance matching resistor R50 one end connects+2.5V voltages, the inverting input of other end connection comparator U7.
Resistance R52 latter end ground connection in parallel with filter capacitor C29, the other end is connecting comparator U7 just by electric capacity C26
Phase input.
Reliability compares the normal phase input end that the Large Copacity resistance R39 two ends bridged with input and output connect comparator U7 respectively
And output end.
Pull-up resistor R44 one end connects+5V voltages, the output end of other end connection comparator U7.
Output filter resistance R48 one end connects the output end of comparator U7, one end of other end connection electric capacity C27, electric capacity
The other end ground connection of C27, the tie point of output filter resistance R48 and electric capacity C27 is exported, and obtains the defeated of accurate reliable frequency converter
Go out frequency OUT_FB.
It is compared by the reference potential after the voltage Ub1 and 2.5V partial pressures by input, so as to obtain recurrent pulse letter
Number, you can as frequency converter output frequency signal.
Comparator module is hysteresis comparator circuit, and is comparator circuit of the homophase input with positive feedback type.Based on whole
Individual frequency converter is three-phase output, and the output that difference channel all the way is had in addition in real application systems is positive and negative by anti-phase input band
Feedback type comparison circuit, such that it is able to obtain pulse sequence situation according to two comparator outputs, thus judges the rotation side of motor
To single channel pulse can only judge rotating speed.Comparison circuit of the homophase input with positive feedback in first analysis chart 2, it is considered to critical condition
When can with " void disconnected " of ideal operational amplifier, " empty short " characteristic is analyzed, and then can obtain two threshold values of hysteresis comparator.
It is illustrated in figure 4 a kind of simplified pinciple figure of comparator module provided in an embodiment of the present invention, the electricity of refer to the attached drawing 2
Road, be calculated analytically obtain Fig. 4 (homophase input is with positive feedback type comparison circuit) upper and lower bound threshold values (wherein R75 and
R77 is input resistance Rin1, R71 is feedback resistance Rf1):
(1) the input upper limit threshold values of Fig. 4:
(2) the input lower limit threshold values of Fig. 4:
VrefIt is reference power source ,+Vz is to represent output comparator to power forward voltage, and-Vz represents the power supply of output comparator
Negative pressure.
Especially, the detection of two-way output line voltage is detected during Fig. 2 and Fig. 3 export three-phase voltage for frequency converter respectively, from
And actual frequency converter output voltage can be obtained, it has been achieved in that the detection of two output line voltages circuit and two proposed by the present invention
Road output frequency detection, and detection signal obtains frequency converter residual voltage according to this, such that it is able to motor direction of rotation after halt instruction
Judged with rotary speed;And then be applied to without velocity control, can also be applied to output voltage detection as
The vector controlled of voltage model, the vector controlled based on neural network estimator and the vector controlled based on fuzzy control theory etc.
Control model.
Presently preferred embodiments of the present invention is the foregoing is only, is not intended to limit the invention, it is all in essence of the invention
Any modification, equivalent and improvement made within god and principle etc., should be included within the scope of the present invention.