Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
  • H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
  • H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using DC to AC converters or inverters
  • H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using DC to AC converters or inverters with pulse width modulation
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
  • H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
  • H02M7/42—Conversion of DC power input into AC power output without possibility of reversal
  • H02M7/44—Conversion of DC power input into AC power output without possibility of reversal by static converters
  • H02M7/48—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
  • H02M7/53—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
  • H02M7/537—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
  • H02M7/5387—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
  • H02M7/53871—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
  • H02M7/53875—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current with analogue control of three-phase output
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
  • H02P23/0077—Characterised by the use of a particular software algorithm
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
  • H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
  • H02P27/047—V/F converter, wherein the voltage is controlled proportionally with the frequency

Definitions

• the present invention relates to an inverter device that controls the number of rotations of a motor by changing the frequency of a voltage applied to the induction motor.
• variable voltage / variable frequency control (hereinafter referred to as VVVF control) is performed.
• VVVF control is such that the magnetic flux of the motor is always kept constant even when the output frequency of the inverter device is changed.
• the ratio of the motor applied voltage to the motor applied frequency is basically controlled.
• the ratio between the output voltage V of the impeller device and the output frequency: the wave number F is controlled to keep the VZF ratio constant.
• Fig. 1 shows an example of a conventional device of the above type.
• 1 is a three-phase or single-phase power supply, which in this case consists of a three-phase power supply.
• Reference numeral 2 denotes an inverter unit (forward conversion unit) of the inverter device, and reference numeral 3 denotes an inverter unit (reverse conversion unit).
• 4 is an induction motor], which is connected to the inverter unit 3 in three phases.
• Reference numeral 12 denotes a signal generation circuit that generates a pulse width modulation signal (hereinafter, referred to as a PW signal) proportional to an external output frequency signal.
• the PWM signal generated by the PWM signal generation circuit 12 is a photo signal.
• FIG. 2 shows an example of the relationship between the PwM signal generated by this circuit and the three-phase terminal voltage.
• FIG. 2 (a) shows a signal at a high output frequency of the inverter unit 3
• FIG. 2 (b) shows a signal at a low output frequency of the inverter unit 3.
• the horizontal direction shows time
• the vertical direction shows output values.
• each sine wave signal has a phase difference of 120 °.
• the ⁇ -phase terminal voltage ⁇ ⁇ is the V-phase terminal voltage V v obtained from the voltage comparison between the sine wave signal 14 and the triangular wave signal 13 is the sine wave signal 1 with a phase difference of 1 It is obtained from a voltage comparison between 5 and the triangular wave signal 13 .
• Each to, W-phase terminal voltage V w is derived from the voltage comparator of a sine wave signal No. 1 6 of the phase difference relative to the sine wave signal 1 5 1 2 O ° '.
• the peak value ratio of 13 is changed according to the frequency.
• the motor applied voltage is high at high frequency (state in Fig. 2a) and low at low frequency (state in Fig. 2b). Control is performed so that the ratio between the motor applied voltage and the frequency is constant.
• a signal is generated by the signal generation circuit 12 and the switching timing of the inverter section 3 is determined.
• C At this time, among the plurality of switching elements of the inverter section 3, A short-circuit prevention period (hereinafter referred to as short-circuit prevention period td) is provided to prevent a short circuit phenomenon caused by simultaneous ignition of the upper and lower elements connected in series.
• the short-circuit prevention period td is described in “Mitsubishi Electric — —
• Inverter devices with different configurations are being considered. This configuration detects the applied voltage applied to the motor via the instantaneous voltage detection circuit,
• the signal output from the sine wave reference voltage circuit based on the V / F command signal and the signal output from the instantaneous voltage detection circuit are compared and input to the circuit, and the inverter is operated based on the input comparison signal. It is driven, and it is possible to correct the zero distortion of the output waveform by feeding back the applied voltage, so that the carrier frequency can be increased up to 20 KHz and noise can be reduced. Has an effect. Power, power,
• VV VF control with a constant V / F ratio, if the power supply voltage supplied to the inverter changes, the output frequency differs for the same output frequency.
• the output voltage was low and stability was lacking.
• a main object of the present invention is to make the carrier frequency non-frequency, reduce the distortion of the output voltage waveform, and provide a stable voltage corresponding to the frequency even when the power supply voltage fluctuates. It is an object of the present invention to provide an inverter device for driving a low noise motor.
• the inverter device of the present invention is an integrated circuit that integrates an inverter output voltage and a magnetic flux command signal having a frequency proportional to an external frequency command output from the magnetic flux indicating signal generating circuit.
• the P7 ⁇ ⁇ ⁇ M signal is generated by comparing the modulated wave signal obtained by amplifying the error of the integrated motor voltage signal with the triangular wave signal that is the carrier frequency of the non-audible frequency. It is.
• the inverter apparatus of the present invention includes a magnetic flux command signal generating circuit for generating a magnetic flux command signal having a frequency proportional to an external inverter output frequency, and an impeller for supplying electric power to the motor.
• An integrating circuit for integrating the output voltage of the motor; an error amplifying circuit for amplifying an error between a motor voltage integration signal output from the integrating circuit and a magnetic flux command signal output from the magnetic flux command signal generating circuit;
• a triangular wave generating circuit for generating a frequency signal, and for generating a pulse width modulation signal based on a comparison between a signal of the error amplifier circuit and a carrier frequency signal formed of a triangular wave.
• a sine wave is used as the magnetic flux command signal
• the magnetic flux indicating signal includes a sine wave and a harmonic component of an odd number of multiples of three of the sine wave. Includes waveforms using integrated signals.
• the inverter device of the present invention is provided with an output of the inverter device. • Including those equipped with an automatic magnetic flux reduction circuit that lowers the peak value of the magnetic flux command signal in inverse proportion to the output frequency when the frequency enters the constant voltage region from the variable voltage and variable frequency control regions.
• FIG. 1 is an electrical configuration diagram of a conventional inverter device
• Figs. 2a and 2b are diagrams showing the relationship between PWM signal generation and three-phase terminal voltage in a conventional inverter device.
• FIG. 3 is an electrical configuration diagram of an inverter device according to one embodiment of the present invention
• FIG. 4 is a diagram illustrating a specific configuration of a magnetic flux command circuit used in one embodiment of the present invention
• FIG. 6 is a diagram showing a specific configuration of the automatic magnetic flux reduction circuit used in the embodiment of the present invention.
• FIG. 7 is a diagram showing an inverter output voltage waveform according to another embodiment of the present invention.
• FIG. 8 is a diagram showing output voltage versus output frequency of the inverter device when the power supply voltage fluctuates.
• FIG. 15 shows the characteristics.
• FIG. 8 and FIG. 21 show the case of a conventional inverter device, and b shows the inverter in one embodiment of the present invention. The case of the device is shown.
• 1 is the power supply
• 2 is the converter
• 3 is the inverter
• a magnetic flux command signal generation circuit for generating a magnetic flux command signal having a frequency proportional to an external inverter output frequency signal;
• the three-phase voltages applied to the motor 4 from the inverter unit 3 are respectively integrated by the integration circuit 6, and the motor voltage integration signals obtained by the integration circuit 6 are converted into three-phase magnetic flux coupling signals, respectively.
• Reference numeral 8 denotes a comparison circuit which compares a carrier frequency signal in the non-audible range (2 OKHZ or more) generated by the triangular wave generation circuit 9 with the above-mentioned modulated wave to generate a PWM signal.
• the driver-circuit 1 O is provided with the short-circuit prevention period td.
• 11 is an automatic magnetic flux reduction circuit. -Next, each configuration and operation will be described.
• reference numeral 5a denotes a converter to which an external inverter output frequency signal is input and which generates a motor applied voltage signal corresponding to the inverter output frequency signal.
• magnetic flux waveform data is stored.
• 5C addresses the memory 5b—counter, 5d multiplies the digital signal of the magnetic flux waveform output from the memory 5b by the peak value signal, and the phase is shifted by 120 ° each.
• D ZA converter that generates a three-phase magnetic flux command signal 0 —
• the magnetic flux coupling signal is 0 S X si no.
• the total of the gains amplified by the error amplifier circuit, the comparator circuit 8, the driver circuit 1 O, the inverter section 3 and the like is represented by G, and the short-circuit prevention period td ⁇ ⁇ the power switching element.
• the influence of disturbances such as switching delays and signal delays is d, the output voltage of the inverter 3 is V M , Assuming that the transfer function of the circuit 6 is 1 (S x T) and ( ⁇ is the time constant of the integrating circuit), the following equation is established.
• Equation (2) indicates that if the peak value signal 0 S of the magnetic flux command signal ⁇ 3 X sinw t is constant, the ratio of the output voltage to the output frequency is automatically fixed.
• VVVF control will be performed. -Also, gain & is sufficient. If it is large, the influence of disturbance V on output voltage v M is reduced, and even if the carrier frequency is not audible, it does not greatly affect output voltage waveform distortion, and noise is reduced. Sound generation can be prevented.
• FIG. 5 shows an inverter output voltage-output frequency characteristic diagram in a case where the induction motor is generally driven by the inverter device to shift from the VVVF control region to the constant voltage control region.
• Low output frequency range in Fig. 5 represents the ratio V ratio Jonojo torque characteristics of the output voltage and output frequency, the output frequency F 0 by a high output frequency range, the output voltage. Constant It shows the constant output characteristics of the above.
• the peak value signal ⁇ 3 of the magnetic flux command signal ⁇ s X si nw t generated by the magnetic flux command signal generating circuit 5 is inversely proportional to the angular velocity W.
• the circuit for this is the automatic magnetic flux reduction circuit 11], and Fig. 6 shows the details.
• iia, iib, iic, iid, and iie are fixed resistors
• 11 f is an operational amplifier
• 11 g is a capacitor
• 111 is a transistor
• 11 i is the control in Fig. 5.
• Output frequency F to transition to constant output voltage control from.
• Terminal for giving the peak voltage value of the modulated 'wave signal.
• transistor 11 h operates to lower the potential of the peak value signal ⁇ 3 of the magnetic flux command signal generating circuit 5 connected to the collector of the transistor 11 ⁇ . Therefore, the peak voltage of the modulated wave output from the error amplifier circuit is always the same as the voltage value of the terminal 11i. According to the above operation, even if the frequency changes, the peak voltage of the modulated wave signal amplified by the error amplifier circuit is automatically constant, and the output voltage from the inverter unit 3 is also always constant. — —
• the modulated sputum signal amplified by the error amplifier circuit is a sine wave
• the inverter output voltage applied to the motor is a sine wave
• the waveform shown in FIG. 7 is an inverter output voltage waveform.
• Figure a shows the inverter output voltage waveform of one of the three phases, and the other two phases are shifted by 120 ° and 240 °, respectively.
• ⁇ is the angular velocity
• ⁇ 0 is the angular velocity when the effective value of the inverter output voltage is at its maximum
• ⁇ is the DC voltage output from the converter unit 2 in FIG.
• the relationship between the inverter output voltage waveform and the effective value of the inverter output voltage is described below.
• the effective value of the power supply voltage is Vr
• the output voltage of the inverter is Vu, Vv, Vvr for each of the three phases. If the capacitor section 2 has an infinitely large capacitor,
• Vu (E 2) x s i ⁇ ⁇ t
• Vv C E 2) x s i n (o t — 120 °)
• Vu-v ⁇ "X (/ V ⁇ 2) X Vr x s in (o) t + 3 ⁇ °) and the effective value of the line-to-line voltage V (u —ma) r are
• This waveform is a sine wave with odd harmonics that are multiples of 3 and the fundamental and nth harmonics (n is an integer of 2 or more) of this waveform are shown in the following equation.
• the fundamental wave may be considered. If the fundamental wave of one phase of the three phases of the inverter output voltage is Vu and the fundamental wave of the output voltage of one phase of the other two phases is Vu, then Vu and Vma are ⁇ .
• Vu-y ⁇ / ⁇ 3 XC 2 / ⁇ 3 ") X (1 / V ⁇ ") ⁇ ⁇ * ⁇ ⁇ 3 ⁇ ( ⁇ ⁇ -
• the inverter for the output voltage waveform in the wave shape shown in ⁇ view stores the data in the integral value of the waveform of the ⁇ diagram fourth diagram Note rie 5 b.
• the relationship between the inverter output frequency and the output voltage when the power supply voltage fluctuates is shown in FIG.
• the relationship between the converter output frequency and the output voltage is shown in Fig. 8b.
• the inverter output voltage is different from the DC voltage, which is the output of the converter, that is, the power supply voltage.
• VVVF control with a constant V / F ratio to the power supply voltage. If the power supply voltage fluctuates, the VZF ratio fluctuates with the fluctuation of the power supply voltage.
• the integrated value of the voltage applied to the motor is fed back.
• V / F ratio in the range that the VVVF control variation in power supply voltage to be determined by the pulse height signal [Phi 3 flux command signal generation circuit 5 thereconnection same output voltage DOO Ru is also at the same output frequency.
• the boundary frequency at which the transition from the VVVF control to the V-constant control changes as shown in FIG. Industrial applicability
• the present invention provides a — —
• the carrier frequency is set to an inaudible frequency.
• the waveform distortion of the output voltage due to the short-circuit prevention period td of the switching element can be reduced. Therefore, it is possible to provide an inverter device that can drive a motor with low noise and can stably obtain an output voltage corresponding to an output frequency.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Inverter Devices (AREA)
• Control Of Ac Motors In General (AREA)

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• 1986
  • 1986-09-12 JP JP61216620A patent/JPS6373898A/ja active Pending
• 1987
  • 1987-09-07 US US07/199,035 patent/US4905135A/en not_active Expired - Lifetime
  • 1987-09-07 GB GB8811305A patent/GB2204160B/en not_active Expired - Lifetime
  • 1987-09-07 WO PCT/JP1987/000663 patent/WO1988002195A1/ja not_active Ceased
  • 1987-09-07 DE DE19873790557 patent/DE3790557T1/de not_active Withdrawn

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