JPH089700A - Air conditioner - Google Patents

Abstract

PURPOSE:To compensate ageing of a vector control operation and a characteristic due to a temperature change by a method wherein the set value of a primary resistance is changed to make the difference of a comparator zero. CONSTITUTION:A shell discharge temperature detector 38, a shell discharge pressure detector 39, a shell intake temperature detector 40 and a shell intake pressure detector 41 for a compressor 1 are connected to an enthalpy arithmetic device 42, and the enthalpy arithmetic device 42 is connected to a torque estimation device A52. In addition, torque estimation devices A52, B53 are connected to a comparator 54, and the comparator 54 is connected to a vector control instruction arithmetic circuit 56. Then, the set value of a primary resistance is changed so as to make the difference of the comparator zero, the primary resistance which is affected by a temperature change is corrected, the actual work load of the compressor 1 is computed according to the Mollier diagram, and a primary resistance value is corrected to make a deviation zero while the deviation from a work load instructed on the basis of a torque current instruction is regarded as the thermal change of the primary resistance. As a result, it is possible to control an inverter without being affected by a temperature change.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner equipped with an inverter control device for vector-controlling a compressor motor.

[0002]

2. Description of the Related Art In recent years, an air conditioner has been widely used which controls the capacity by increasing or decreasing the number of revolutions of a compressor by using an inverter device which makes a frequency of a power source variable.

A conventional air conditioner will be described below with reference to the drawings. FIG. 19 is a block diagram showing the configuration of a conventional air conditioner. In the figure, 1 is a compressor, 2 is a four-way valve, 3 is an indoor heat exchanger, 4 is a decompression device, and 5
Is an outdoor heat exchanger, and these are connected in a ring to form a refrigeration circuit. 6 is an indoor fan, and 7 is an outdoor fan. Reference numeral 8 is an inverter control device that controls the rotation speed of the compressor 1, and 9 is a three-phase AC power supply. Further, 10 is an indoor unit, and 11 is an outdoor unit.

As the control system of the inverter controller 8, vector control is often adopted because of its excellent response and power saving, and vector control is also applied to the variable speed control system of the compressor of the air conditioner. Has been done.

This vector control method includes a magnetic flux detection type vector control method in which a secondary magnetic flux is detected as a vector quantity and used as a control signal of a primary current, and a slip frequency in which a magnetic flux vector is calculated and controlled based on a motor constant. A shape vector control method is known. As these conventional techniques, for example, there is one disclosed in Japanese Patent Laid-Open No. 2-202387.

FIG. 20 is a block diagram showing the configuration of a slip frequency type vector controller which is one of the conventional inverter controllers for an air conditioner. In the figure, the compressor 1
Is supplied with AC power of variable frequency by the power converter 12, and the primary currents ic1, ib1 and ia1 of the compressor 1 are detected by the current detectors 13, 14 and 15, respectively, and by the speed detector 16 which detects the speed. The rotation angular frequency ωR is detected. The secondary magnetic flux command φ 2 ^* is converted into the exciting current command id 1 ^* by the exciting current calculator 17 and the torque command τ ^*.
Is converted by the torque current calculator 18 into a torque current command iq1 ^* based on the secondary resistance R2 ^* of the motor input thereto. The exciting current command id1 ^* and the torque current command iq1 ^* are transmitted by the vector rotator 19 to the rotating magnetic flux coordinate system (d axis, q
The current value i1 ^* on the axis) and the phase angle σ ^* are converted. Here, the vector rotator 19 performs calculation according to the equations (1) and (2).

Σ ^* = tan ^-1 {(R1 · id1 ^* −ω1 · (L1 + L2) · iq1 ^* ) + (E + ω1 · (L1 + L2) · id1 ^* + R1 · iq1 ^* )} ・ ・ ・ ・ ・ ・ ・ ・ ( 1) V1 ^* = (E + ω1 ・ (L1 + L2) ・ id1 ^* + R1 ・ iq1 ^* ) ・ cosσ ^* + (R1 ・ id1 ^* −ω1 ・ (L1 + L2) ・ iq1 ^* ) ・ sinσ ^*・ ・ ・ ・ ・ ・ ・ ・ ( 2) Here, L1 is a self-primary inductance, L2 is a self-secondary inductance, E is an induced electromotive force, and R1 is a primary resistance. V1 ^* is a voltage value that gives a current value i1 ^* .

On the other hand, in the slip frequency calculator 20,
Using the torque current command iq1 ^* , the secondary magnetic flux command φ2 ^*, and the motor secondary resistance R2 ^* , a slip frequency command ωs ^* is generated, and the adder 21 generates the rotational angular frequency ωR and the slip frequency command ωs ^.
The sum of s ^* , that is, the primary angular frequency ω 1 is generated. Further, the primary angular frequency ω1 is integrated by the integrator 22 to obtain the phase angle φ1 ^* of the rotating coordinate axis, and the adder 23 calculates the sum θ1 ^* with the phase angle σ ^* on the dq axes. Here, the adder 23 calculates according to the equation (3).

Θ1 ^* = σ ^* + φ1 ^* ... (3) θ1 ^* obtained by the equation (3) is the position of the current seen on the stationary axis.

The absolute value i1 ^* of the primary current is a combined current of the exciting current component and the torque current component, and the phase angle θ1 ^* indicates its position on the stationary two axes. Therefore, the two-phase / three-phase converter 24 converts the absolute value i1 ^{* of} the primary current and the phase angle θ1 ^* of the primary current into two-phase / three-phase conversion to generate three-phase current commands ia1 ^* , ib.
It generates a 1 ^* and ic1 ^*, the comparator 25, 26 and 27 by the output current of the power converter ia1 ^*, compared with ib1 ^* and ic1 ^*. After that, the current control is performed by a normal proportional type controller or a combination type controller for proportional and integral so that the actual current value matches the command current value.

Vector control becomes possible by the above method. The slip frequency command ωs ^* is the slip frequency calculator 2
It is calculated by the equation (4) by 0.

Ωs ^* = − (M ^* · R2 ^* · iq1 ^* ) / (L2 ^* · φ2 ^* ) (4) where R2 ^* is the secondary resistance and L2 ^* is the secondary resistance. Inductance,
M ^* indicates mutual inductance.

FIG. 21 is a block diagram showing the configuration of the torque current calculator 18. In the figure, a signal output from the coefficient unit 25, 26 and the differentiator 27 for the torque command τ ^* and a signal output only through the coefficient unit 25 are generated, and the adder 28 adds these signals to generate a torque current. The command iq1 ^* is output.

FIG. 22 is a block diagram showing the configuration of the slip frequency calculator 20. In the figure, the torque current command i
The signal output from q1 ^* through the coefficient multipliers 29 and 30 is divided by the secondary magnetic flux command φ2 ^* in the divider 31 to obtain the coefficient multiplier 3
The slip frequency command ω s ^* is output through 2.
When the primary voltage command V1 ^* shown in the equations (1) and (2) is calculated, the primary resistance R1 is directly involved, but in the conventional vector control system, the primary resistance R1 is controlled to be constant. .

Next, FIG. 23 shows a conventional air conditioner.
Magnetic flux detection type vector control, which is one of the inverter control devices
It is a block diagram which shows the structure of an apparatus. In the figure, magnetic flux
Are the voltages Va1, Vb1 and Vc1 applied to the compressor 1.
Detected by current detectors 13, 14 and 15 respectively
Based on the generated primary currents ia1, ib1 and ic1
It is calculated by the calculator 33. Of the magnetic flux calculator 33
The output is the stationary biaxial components φα1 and φβ1 of the secondary magnetic flux vector.
Yes, the vector analyzer 34 determines the absolute value component | φ
2 | and the phase angles sin φ and cos φ are converted. On the other hand, the secondary magnet
Bundle command φ2^*And generated torque command τ^*Is an exciting current calculator 17
And the processing of the torque current calculator 18 are performed, and the rotating magnetic flux is d
Exciting current command id1 in the rotating coordinate system considering the axis^*, To
Luk current command iq1^*Processed into a vector rotator 35
The exciting current command id1^*, Torque current command iq1^*The above
Current command iα1 in the stator coordinate form based on each phase φ^*, I
β1 ^*Convert to. That is, the output of the vector rotator 35
iα1^*, Iβ1^*Generates secondary magnetic flux components φα1 and φβ1
The current for the purpose of converting with the two-phase to three-phase converter 36
Primary current command ia1 of power converter 12^*, Ib1^*And ic1
^* To generate the coefficient units 25 and 26 and the differentiator 2 respectively.
7 to compare and control the output current of the power converter 12
It

As described above, in the magnetic flux detection type vector control system, since the magnetic flux is directly controlled by giving the current command, the inductance value and the resistance value on the secondary side, which has the most uncertainties in the motor constant, are not required. . Therefore, even if the constants of the primary circuit and the secondary circuit of the motor inside the compressor 1 change, the input primary voltages Va1 and Vb1 of the magnetic flux calculator 33 are changed.
And Vc1 and the input primary currents ia1, ib1 and ic1 are accepted as changes, and the calculation result of the magnetic flux changes accordingly, so that the deterioration of the vector control characteristics due to the parameter changes is small. However, the estimation of the magnetic flux by the magnetic flux calculator 33 and the vector analyzer 34 has many problems in the accuracy and resolution of the sensor, and in particular, there is a problem in the calculation accuracy due to the voltage distortion at low speed, which is not practically used. The reality is not.

[0017]

In such a conventional air conditioner, when the primary resistance R1 changes depending on the temperature in the practical inverter control device of the slip frequency type vector control, the primary voltage command V1 ^* is calculated. A large error occurs, and the excellent control characteristic originally possessed by the vector control cannot be maintained, and the characteristic deteriorates. Therefore, it is necessary to detect or estimate the fluctuation of the primary resistance due to temperature by some means and reflect it in the process of calculating the primary voltage command to compensate for the excellent control characteristic of the vector control.

The present invention solves the above problems and provides an air conditioner capable of compensating for the temperature change of the primary resistance of the motor in the slip frequency type vector control and for compensating the vector control and the characteristic deterioration due to the temperature change. The purpose is to

[0019]

According to a first aspect of the present invention, there is provided a compressor whose rotation speed is controlled by a power converter, a current detector for detecting a primary side current of the compressor, and the current detector. The current detection circuit for A / D converting the primary current value obtained by the above, the excitation current calculator for calculating the excitation current from the secondary magnetic flux command, the output of the current detection circuit and the torque from the excitation current of the excitation current calculator. A torque current calculator for calculating a current, a torque estimator B for obtaining a torque value from the output of the torque current calculator, an exciting current of the exciting current calculator and a torque current of the torque current calculator for the compressor. A vector rotator that calculates the output primary voltage and phase angle,
A slip frequency calculator that calculates a slip angular frequency from the secondary magnetic flux command and the torque current of the torque current calculator,
An adder that calculates the actual rotational angular frequency that is the current rotational speed of the compressor from the slip angular frequency of the slip frequency calculator and the desired rotational angular frequency setting value, and a shell that detects the shell discharge temperature of the compressor Discharge temperature detector, shell discharge pressure detector for detecting the shell discharge pressure of the compressor, shell suction temperature detector for detecting the shell suction temperature of the compressor, and shell suction pressure for detecting the shell suction pressure A detector, the shell discharge pressure detector, the shell discharge temperature detector, the shell suction pressure detector, and an enthalpy calculator that calculates a compressor work from output signals of the shell suction temperature detector, and A torque estimator A that calculates an estimated torque value of the compressor based on an output signal from an enthalpy calculator, an output signal of the torque estimator A, and the torque estimation value. A comparator for calculating the difference between the output signals of the comparator B and a primary resistance identifier for identifying the primary resistance required for the calculation in the vector rotator from the output signal of the comparator. An air conditioner in which the primary resistance affected by temperature change is corrected by changing the set value of the primary resistance so as to be zero, and the present invention according to claim 2 is the power converter. A compressor whose rotation speed is controlled by a current detector, a current detector for detecting the primary side current of the compressor, a current detection circuit for A / D converting the primary current value obtained by the current detector, and a secondary magnetic flux command From the output of the current detection circuit and the exciting current of the exciting current calculator, a torque current calculator that calculates the torque current from the output of the current detecting circuit, and the torque value from the output of the torque current calculator. Desired torque Stationary machine B, vector rotor for calculating the primary voltage and phase angle output to the compressor from the exciting current of the exciting current calculator and the torque current of the torque current calculator, the secondary magnetic flux command and the torque A slip frequency calculator that calculates the slip angular frequency from the torque current of the current calculator, an adder that calculates the slip angular frequency of the slip frequency calculator and the desired number of revolutions, and the shell discharge temperature of the compressor Shell discharge temperature detector, shell suction pressure detector for detecting shell suction pressure of the compressor, shell suction temperature detector for detecting shell suction temperature, shell discharge temperature detector and shell suction pressure detection And an enthalpy calculator that calculates the work of the compressor from the output signals of the shell and the shell suction temperature detector, and the output signal from the enthalpy calculator. Torque estimator A for calculating the estimated torque value of the compressor
And a comparator that calculates the difference between the output signal of the torque estimator A and the output signal of the torque estimator B, and identify the primary resistance required for the calculation in the vector rotator from the output signal of the comparator. A primary resistance identifier and, by changing the setting value of the primary resistance so as to make the difference of the comparator zero, an air conditioner configured to correct the primary resistance affected by temperature changes, The present invention according to claim 3 provides a compressor whose rotation speed is controlled by a power converter,
A current detector for detecting the primary side current of the compressor, a current detection circuit for A / D converting the primary current value obtained by the current detector, and an exciting current calculator for calculating an exciting current from a secondary magnetic flux command. A torque current calculator for calculating a torque current from the output of the current detection circuit and the exciting current of the exciting current calculator; a torque estimator B for obtaining a torque value from the output of the torque current calculator; and the exciting current. A vector rotator that calculates the primary voltage and phase angle output to the compressor from the exciting current of the calculator and the torque current of the torque current calculator; slip from the secondary magnetic flux command and the torque current of the torque current calculator. A slip frequency calculator for calculating the angular frequency, and an actual rotation angle frequency that is the current rotation speed of the compressor from the slip angle frequency of the slip frequency calculator and the desired rotation angle frequency setting value. An adder for calculating, a shell discharge temperature detector for detecting the shell discharge temperature of the compressor, a shell discharge pressure detector for detecting the shell discharge pressure of the compressor, and a shell suction temperature of the compressor From the shell suction temperature detector, the shell discharge temperature detector, the shell discharge pressure detector, and the output signal of each of the shell suction temperature detector, the enthalpy calculator, and the enthalpy calculator. A torque estimator A for calculating an estimated torque value of the compressor according to the output signal of
A comparator that calculates the difference between the output signal of the torque estimator A and the output signal of the torque estimator B, and a primary resistance that identifies the primary resistance required for the calculation in the vector rotator from the output signal of the comparator. An air conditioner comprising an identifier and changing the set value of the primary resistance so as to make the difference between the comparators zero, thereby correcting the primary resistance affected by the temperature change.

[0020]

In the present invention according to claim 1, the result of estimating the torque of the compressor from the discharge temperature, the discharge pressure, the suction temperature and the suction pressure is compared with the result of the torque command value, and the difference is made zero. By changing the setting value of the primary resistance in this way, the influence of the temperature of the primary resistance used in the calculation of the primary voltage command value is corrected to prevent the control accuracy from degrading, and the control accuracy does not deteriorate due to the temperature change. Realize a harmony device. Further, in the present invention according to claim 2, the result of estimating the torque of the compressor from the discharge temperature, the suction pressure, and the suction temperature is compared with the result of the torque command value, and the primary resistance is set so that the difference becomes zero. By changing the set value of 1, the influence of the temperature of the primary resistance used in the calculation of the primary voltage command value is corrected to prevent the control accuracy from decreasing, and an air conditioner with low cost and good control accuracy is realized. Claim 3
In the present invention, the result of estimating the torque of the compressor from the discharge temperature, the discharge pressure, and the suction temperature is compared with the result of the torque command value, and the set value of the primary resistance is changed so that the difference becomes zero. By doing so, the influence of the temperature of the primary resistance used in the calculation of the primary voltage command value is corrected, the control accuracy is prevented from lowering, and a low cost air conditioner is realized.

[0021]

【Example】

(Embodiment 1) An embodiment of the air conditioner according to the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing the configuration of this embodiment. In addition,
The same numbers are given to the same components as the conventional example, and the detailed description is omitted. In FIG. 1, 37 is an accumulator for making the refrigerant completely sucked into the compressor 1 only, 38 is a shell discharge temperature detector for detecting the shell discharge temperature of the compressor 1, 39 is the shell discharge pressure of the compressor 1. , 40 is a shell suction pressure detector for detecting the shell suction temperature of the compressor 1, 41 is a shell suction pressure sensor for detecting the shell suction pressure of the compressor 1, and 41 is a shell discharge temperature detector. The detector 38, the shell discharge pressure detector 39, the shell suction temperature detector 40, and the shell suction pressure detector 41 are connected to an enthalpy calculator 42, and the enthalpy calculator 42 is connected to a torque estimator A52. Further, the torque estimator A52 is connected to the comparator 54. Reference numeral 53 is a torque estimator B that estimates the torque from the torque current command value iq1 ^* and is connected to the comparator 54.
The comparator 54 is connected to the vector control command calculation circuit 56. The current detectors 13, 14 and 15 are connected to the vector control command calculation circuit 56 via the current detection circuit 44.

FIG. 2 is a block diagram showing the configuration of the inverter control device in this embodiment. In the figure, the exciting current calculator 43 outputs the exciting current command value id1 ^* from the self-secondary inductance L2 which is a motor constant and the secondary exciting command value φ2 ^* according to the equation (5).

Id1 ^* = 1.23 · iu · cos θ + (0.7 · iu−1.4 · iw) (5) where 1u is the primary current value of the current detector 13, 1w is the primary current value of the current detector 15.

The torque current calculator 47 is a current detection circuit 4
The torque current command value iq ^* is output by calculating the primary current from 4 by the equation (6).

Iq1 ^* = − 1.23 · iu · sin θ + (0.7 · iu−1.4 · iw) (6) where 1u is the primary current value of the current detector 13. 1w is the primary current value of the current detector 15.

The vector rotation origin 48 is used for the exciting current calculation 43.
By calculating the exciting current command value id1 ^* and the torque current of the torque current calculator 47 iq1 ^* (1) by the formula and (2) below, and outputs a primary voltage command value V1 ^* and phase angle sigma ^*.

The output phase angle σ ^* is input to the adder 23, and the output phase angle θ 1 is the two-phase to three-phase converter 4.
It is connected to the power converter 12 via 9.

The primary resistance identifier 55 identifies the primary resistance from the output of the comparator 54, and the vector rotator 48
It is connected to the. The slip frequency calculator 50 calculates the slip angular frequency ωs ^* by the equation (4) using the secondary magnetic flux command φ2 ^* and the torque current command value iq1 ^* which is the output of the torque current calculator 47, and the adder 51 Output to. Further, the adder 51 adds the slip frequency ωs ^* and the rotational angular frequency set value ω0, and outputs the actual rotational angular frequency ω1 to the integrator 22.

Hereinafter, shell discharge pressure, shell discharge temperature,
With reference to FIGS. 3 to 6, the enthalpy that is the work of the compressor 1 is calculated from the shell suction pressure and the shell suction temperature, the torque is estimated from the calculation result, and finally the primary resistance is identified. While explaining. Figure 3
Is a Mollier diagram showing the relationship between the enthalpy and the pressure of the refrigerant in the refrigeration cycle, the vertical axis gives pressure, and the horizontal axis gives enthalpy. As shown in FIG. 1, since the accumulator 37 is provided, the heating degree becomes 0 degree,
It becomes the Mollier diagram shown in FIG. From this Mollier diagram, the shell discharge pressure P1 and the shell discharge temperature T2 of the compressor 1 are shown.
The enthalpy E2 can be calculated from the above, and the enthalpy E1 can be calculated from the shell suction pressure P2 and the shell suction temperature T1. At this time, the work load AW of the compressor 1 is AW = E2
Can be calculated as -E1.

Shell discharge temperature T2 detected by shell discharge temperature detector 38, shell discharge pressure P1 detected by shell discharge pressure detector 39, shell suction temperature T1 detected by shell suction temperature detector 40, and shell suction temperature The shell suction pressure P2 detected by the pressure detector 41 is input to the enthalpy calculator 42, respectively. Enthalpy calculator 42
Calculates AW, which is the work of the compressor, from the Mollier diagram shown in FIG. 3, and inputs the result to the torque estimator A.
In the torque estimator A, from the relationship between the compressor work AW and the torque τ ^** shown in FIG. 4, the current work AW1 of the compressor 1 is calculated.
The torque τ 1 ^** is estimated from the output and output to the comparator 54. Further, the torque current command value iq1 ^* output from the torque current calculator 47 is input to the torque estimator B. The torque estimator B calculates the torque τ from the current torque current command value iq11 ^{* based on} the relationship between the torque current command value iq1 ^* and the torque τ ^* shown in FIG.
1 ^* is estimated and output to the comparator 54. The comparator 54 calculates the torque deviation Δτ according to the calculation of the equation (7).

Δτ = τ ^* −τ ^** (7) Here, τ ^* is the output of the torque estimator B, and τ ^** is the output of the torque estimator A.

The operation of the primary resistance identifier 55 will be described below with reference to FIG. From the relationship between the torque deviation Δτ and the primary resistance correction value ΔR1 ^* shown in FIG. 6 using Δτ1 which is the output of the comparator 54, the primary resistance correction amount ΔR11 ^{* in} this case is obtained ^.
Is determined and the primary resistance is identified according to the equation (8).

R1 = R1 + ΔR11 ^* ... (8) Here, R1 is a primary resistance initial setting value. In this way, the corrected primary resistance value R1 is the vector rotator 48
Input to the primary voltage command value V1 ^* and the phase angle σ
^* Is corrected, and as a result, the compressor 1 is operated via the two-phase to three-phase converter 49 and the power converter 12.

As described above, according to this embodiment, the primary resistance that changes with temperature is used to obtain the torque from the shell discharge pressure, the shell discharge temperature, the shell suction pressure, and the shell suction temperature, and this is compared with the torque command value. Thus, by detecting the temperature change of the primary resistance and correcting the primary resistance value, the slip frequency type vector control that is strong against the influence of temperature becomes possible. Although four sensors are required, since the torque is calculated from the actual measured value, the primary resistance can be corrected accurately with respect to the temperature change and easily realized.

(Embodiment 2) An embodiment of the air conditioner according to the present invention will be described below with reference to the drawings. FIG. 7 is a block diagram showing the configuration of this embodiment. The same components as those in the embodiment shown in FIG. 1 will be assigned the same reference numerals and detailed explanations thereof will be omitted. FIG. 8 is a block diagram showing the configuration of the inverter control device in this embodiment. The same components as those of the inverter control device according to the first embodiment shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted. The present embodiment is different from the first embodiment in that the work of the compressor is estimated without the shell discharge pressure detector 39, and the primary resistance identification method is similar to that of the first embodiment.

The enthalpy which is the work of the compressor 1 is calculated from the shell discharge temperature, the shell suction pressure and the shell suction temperature, the torque is estimated from the calculation result, and finally the primary resistance is identified. A description will be given with reference to the drawings. FIG. 9 is a Mollier diagram showing the relationship between refrigerant pressure and enthalpy, where the vertical axis represents pressure and the horizontal axis represents enthalpy. As shown in FIG. 7, since the accumulator 37 is provided, the heating degree becomes 0 degree, and the Mollier diagram shown in FIG. 9 is obtained. From the Mollier diagram shown in FIG. 9, the enthalpy E1 can be calculated from the shell suction pressure P2 of the compressor 1 and the shell suction temperature T1 detected by the shell suction temperature detector 40, and the isentropic line and shell starting from this intersection point. The intersection of the discharge temperatures T2 becomes the estimated value of the enthalpy E2. Therefore, the work load AW of the compressor 1 is
It can be estimated as AW = E2-E1.

The shell discharge temperature T2 detected by the shell discharge temperature detector 38, the shell suction temperature T1 detected by the shell suction temperature detector 40, and the shell suction pressure P2 detected by the shell suction pressure detector 41 are calculated by the enthalpy calculation. Vessel 42
Is input to The enthalpy calculator 42 calculates the compressor work AW from the Mollier diagram of FIG. 9 by the above estimation, and inputs the result to the torque estimator A. In the torque estimator A, the compressor work AW and the torque τ shown in FIG.
^From the relationship of ^**, the torque τ2 ^** is estimated from the current work AW2 of the compressor 1 and output to the comparator 54. Further, the torque current command value iq1 ^* output from the torque current calculator 47
Is input to the torque estimator B. The torque estimator B calculates the torque τ2 ^* from the current torque current command value iq12 ^{* according} to the relationship between the torque current command value iq1 ^* and the torque τ ^* shown in FIG.
Is estimated and output to the comparator 54. The comparator 54 calculates the torque deviation Δτ according to the calculation of the equation (7).

The operation of the primary resistance identifier 55 will be described below. Using △ .tau.2 which is the output of the comparator 54, determines the primary resistance correction amount △ R12 in this case from the torque deviation △ tau primary resistance correction amount △ R1 ^* relationship 12 ^*,
The primary resistance is identified according to the equation (9).

R1 = R1 + ΔR12 ^* (9) Here, R1 is the primary resistance initial setting value.

Thus, the corrected primary resistance value R1
Is input to the vector rotator 48, and the primary voltage command value V1 ^* and the phase angle σ ^* are corrected. As a result, the compressor 1 is operated via the two-phase / three-phase converter 49 and the power converter 12. To be done.

As described above, according to the air conditioner of this embodiment, the primary resistance that changes with temperature is used to obtain the torque from the shell discharge pressure, the shell discharge temperature, and the shell intake temperature, and this is compared with the torque command value. Thus, by detecting the temperature change of the primary resistance and correcting the primary resistance value, it becomes possible to perform the slip frequency type vector control that is strong against the influence of temperature. Further, as compared with the first embodiment, the accuracy is slightly lowered because there is no pressure information on the discharge side of the compressor 1,
In terms of cost, a discharge pressure sensor is not required, so that a cost reduction effect can be obtained, and it can be easily realized.

(Embodiment 3) An embodiment of the air conditioner of the present invention according to claim 3 will be described below with reference to the drawings. FIG. 13 is a block diagram showing the configuration of this embodiment. Further, FIG. 14 is a block diagram showing the configuration of the inverter in this embodiment. The same components as those of the first embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals, and detailed description thereof will be omitted. The present embodiment is different from the first embodiment in that the work of the compressor is estimated without the shell suction pressure detector, and the primary resistance identification method is the same as in the first embodiment.

The enthalpy which is the work of the compressor 1 is calculated from the shell discharge temperature, the shell discharge pressure and the shell suction temperature, the torque is estimated from the calculation result, and finally the primary resistance is identified. A description will be given with reference to the drawings.

FIG. 15 is a Mollier diagram showing the relationship between the refrigerant pressure and the enthalpy, where the vertical axis represents pressure and the horizontal axis represents enthalpy. As shown in FIG. 13, since the accumulator 37 is provided, the heating degree becomes 0 degree,
It becomes the Mollier diagram shown in FIG. From this Mollier diagram, the shell discharge pressure P1 of the compressor 1 and the shell discharge temperature T
The enthalpy E2 can be calculated from 2, and the intersection of the isentropic line starting from this intersection and the shell intake temperature T1 becomes the estimated value of the enthalpy E1. Therefore, the work load AW of the compressor can be estimated from the relationship of AW = E2-E1. Shell discharge temperature T2 detected by shell discharge temperature detector 38
The shell discharge temperature P1 detected by the shell discharge pressure detector 39 and the shell suction temperature T1 detected by the shell suction temperature detector 40 are input to the enthalpy calculator 42. The enthalpy calculator 42 calculates AW, which is the work of the compressor 1, from the Mollier diagram shown in FIG. 15, and inputs the result to the torque estimator A. In the torque estimator A, the work amount AW and the torque τ ^{** of} the compressor 1 shown in FIG.
The torque τ3 ^** is estimated from the current work amount AW3 of the compressor 1 based on the relationship with, and output to the comparator 54. Further, the torque current command value iq1 output from the torque current calculator 47
^* Is input to the torque estimator B. The torque estimator B, and the torque current command value iq1 ^* and the torque tau ^* relationship of FIG. 17, estimates the current torque current command value Iq13 ^* from the torque .tau.3 ^*, and outputs to the comparator 54. In the comparator 54, (7)
The torque deviation Δτ is calculated according to the calculation of the equation.

The operation of the primary resistance identifier 55 will be described below with reference to FIG. Using the output Δτ 3 of the comparator 54, the primary resistance correction amount ΔR 13 ^* in this case is determined from the relationship between the torque deviation Δτ and the primary resistance correction amount ΔR 1 ^* shown in FIG. ) Identifies the primary resistance according to the equation.

R1 = R1 + ΔR13 ^* ... (10) Here, R1 is a primary resistance initial setting value.

In this way, the corrected primary resistance R1 is input to the vector rotator 48 so that the primary voltage command V
The 1 ^* and phase angle σ ^* were modified, and this result resulted in two-phase −
Compressor 1 via three-phase converter 49 and power converter 12
Is driven.

As described above, according to the present embodiment, the primary resistance which changes with temperature is determined by calculating the torque from the shell discharge pressure, the shell discharge temperature and the shell suction temperature, and comparing this with the torque command value to determine the primary resistance. By detecting the temperature change and correcting the primary resistance value, it becomes possible to perform the slip frequency type vector control that is strong against the influence of temperature. Also,
Although the means of the present embodiment is lower in accuracy than the means of the second embodiment, the suction pressure sensor used in the first and second embodiments is higher in accuracy and cost than the discharge pressure sensor. Therefore, the means of this embodiment which does not use the suction pressure sensor can obtain a large cost reduction effect.

[0049]

As is apparent from the above description, the present invention according to claim 1 provides a compressor whose rotation speed is controlled by a power converter, and a current detector which detects the primary side current of the compressor. , The primary current value obtained by the current detector is A / D
A current detection circuit for converting, an exciting current calculator for calculating an exciting current from a secondary magnetic flux command, a torque current calculator for calculating a torque current from the output of the current detecting circuit and the exciting current of the exciting current calculator, A torque estimator B for obtaining a torque value from the output of the torque current calculator, and an exciting current of the exciting current calculator and a primary voltage and a phase angle to be output to the compressor from the torque current of the torque current calculator. A vector rotator, a slip frequency calculator that calculates a slip angular frequency from the torque current of the secondary magnetic flux command and the torque current calculator, and a slip angular frequency of the slip frequency calculator and a desired rotation angular frequency set value An adder that calculates an actual rotational angular frequency that is the current rotational speed of the compressor; a shell discharge temperature detector that detects the shell discharge temperature of the compressor; , A shell discharge pressure detector for detecting the shell discharge pressure, a shell suction temperature detector for detecting the shell suction temperature of the compressor, a shell suction pressure detector for detecting the shell suction pressure, and the shell discharge pressure detection And an enthalpy calculator that calculates a compressor work amount from output signals of the shell discharge temperature detector, the shell suction pressure detector, and the shell suction temperature detector, and an output signal from the enthalpy calculator. A torque estimator A for calculating an estimated torque value of a compressor, a comparator for calculating a difference between an output signal of the torque estimator A and an output signal of the torque estimator B, and the vector from the output signal of the comparator. A primary resistance identifier for identifying a primary resistance necessary for calculation in the rotator, and changing the set value of the primary resistance so that the difference between the comparators becomes zero. By so doing, the primary resistance affected by the temperature change is corrected, and the present invention according to claim 2 detects the compressor whose rotation speed is controlled by the power converter and the primary side current of the compressor. The current detector and the primary current value obtained by the current detector are A
A current detecting circuit for D / D conversion, an exciting current calculator for calculating an exciting current from a secondary magnetic flux command, and a torque current calculator for calculating a torque current from the output of the current detecting circuit and the exciting current of the exciting current calculator. A torque estimator B that obtains a torque value from the output of the torque current calculator, an excitation current of the excitation current calculator, a primary voltage and a phase angle output to the compressor from the torque current of the torque current calculator. A vector rotor for calculating, a slip frequency calculator for calculating a slip angular frequency from the secondary magnetic flux command and a torque current of the torque current calculator, and a slip angular frequency of the slip frequency calculator and a desired number of revolutions. An adder for calculating, a shell discharge temperature detector for detecting the shell discharge temperature of the compressor, a shell suction pressure detector for detecting the shell suction pressure of the compressor, and the system A shell suction temperature detector for detecting a suction temperature, an enthalpy calculator for calculating a compressor work amount from respective output signals of the shell discharge temperature detector, the shell suction pressure detector, and the shell suction temperature detector. , A torque estimator A for calculating a torque estimated value of the compressor based on an output signal from the enthalpy calculator, and a comparator for calculating a difference between the output signal of the torque estimator A and the output signal of the torque estimator B. And a primary resistance identifier for identifying a primary resistance required for calculation in the vector rotator from the output signal of the comparator, and changing the set value of the primary resistance so that the difference between the comparators becomes zero. By letting
Correct the primary resistance affected by the temperature change,
The present invention according to claim 3 provides a compressor whose rotation speed is controlled by a power converter, a current detector for detecting a primary side current of the compressor, and a primary current value obtained by the current detector. A / D conversion current detection circuit, excitation current calculator for calculating excitation current from secondary magnetic flux command, torque current calculation for calculating torque current from output of current detection circuit and excitation current of excitation current calculator , A torque estimator B for obtaining a torque value from the output of the torque current calculator, a primary voltage and a phase angle output from the exciting current of the exciting current calculator and the torque current of the torque current calculator to the compressor. , A slip frequency calculator that calculates a slip angular frequency from the secondary magnetic flux command and the torque current of the torque current calculator, and a slip angular frequency of the slip frequency calculator An adder that calculates the actual rotational angular frequency that is the current rotational speed of the compressor from a desired rotational angular frequency set value, a shell discharge temperature detector that detects the shell discharge temperature of the compressor, and a compressor Shell discharge pressure detector for detecting shell discharge pressure, shell suction temperature detector for detecting shell suction temperature of the compressor, shell discharge temperature detector, shell discharge pressure detector, and shell suction temperature detector , An enthalpy calculator that calculates a compressor work amount from the respective output signals, a torque estimator A that calculates a torque estimated value of the compressor by an output signal from the enthalpy calculator, and an output of the torque estimator A. A comparator for calculating the difference between the signal and the output signal of the torque estimator B, and the primary resistance required for the calculation in the vector rotator is identified from the output signal of the comparator. A secondary resistance identifier is provided, and by changing the setting value of the primary resistance so as to make the difference between the comparators zero, the primary resistance affected by the temperature change is corrected. The actual work of the machine is calculated according to the Mollier diagram, and the deviation from the specified work based on the torque current command is assumed to be due to the thermal change of the primary resistance, and the primary resistance value is corrected so that the deviation becomes zero. By doing so, the inverter control of the air conditioner can be performed without being affected by the temperature change.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of an air conditioner of the present invention according to claim 1.

FIG. 2 is a block diagram showing a configuration of an inverter control device according to the embodiment.

FIG. 3 is a Mollier diagram in the example.

FIG. 4 is a characteristic diagram showing the relationship between the work of the compressor and the estimated torque value τ ^** in the same example.

FIG. 5 is a characteristic diagram showing a relationship between a torque current command value iq1 ^* and an estimated torque value τ ^{* in} the embodiment.

FIG. 6 is a characteristic diagram showing a relationship between a difference between estimated torque values τ ^* and τ ^** and a primary resistance correction amount ΔR11 ^{* in} the example.

FIG. 7 is a block diagram showing the configuration of an embodiment of the present invention according to claim 2;

FIG. 8 is a block diagram showing a configuration of an inverter control device according to the embodiment.

FIG. 9 is a Mollier diagram in the example.

FIG. 10 is a characteristic diagram showing the relationship between the work of the compressor and the estimated torque value τ ^{** in} the same example.

FIG. 11 is a characteristic diagram showing a relationship between a torque current command value iq1 ^* and an estimated torque value τ ^{* in} the example.

FIG. 12 is a characteristic diagram showing the relationship between the difference between estimated torque values τ ^* and τ ^** and the primary resistance correction amount ΔR12 ^{* in} the example.

FIG. 13 is a block diagram showing the configuration of an embodiment of the present invention according to claim 3;

FIG. 14 is a block diagram showing the configuration of an inverter control device in the example.

FIG. 15 is a Mollier diagram in the example.

FIG. 16 is a characteristic diagram showing the relationship between the work of the compressor and the estimated torque value τ ^{** in} the example.

FIG. 17 is a characteristic diagram showing the relationship between the torque current command value iq1 ^* and the estimated torque value τ ^{* in} the example.

FIG. 18 is a characteristic diagram showing the relationship between the difference between the estimated torque values τ ^* and τ ^** and the primary resistance correction amount ΔR13 ^{* in} the example.

FIG. 19 is a block diagram showing a configuration of a conventional air conditioner.

FIG. 20 is a block diagram showing a configuration of a slip frequency vector control inverter device of the air conditioner.

FIG. 21 is a block diagram showing a configuration of a torque current calculator of a slip frequency type vector control inverter device of the air conditioner.

FIG. 22 is a block diagram showing a configuration of a slip frequency calculator of a slip frequency vector control inverter device of the air conditioner.

FIG. 23 is a block diagram showing a configuration of a magnetic flux detection type vector control inverter device of the air conditioner.

[Explanation of symbols]

 1 Compressor 13, 14, 15 Current Detector 38 Shell Discharge Temperature Detector 39 Shell Discharge Pressure Detector 40 Shell Suction Temperature Detector 41 Shell Suction Pressure Detector 42 Enthalpy Calculator 43 Excitation Current Calculator 47 Torque Current Calculator 48 Vector rotator 50 Slip frequency calculator 51 Adder 52 Torque estimator A 53 Torque estimator B

Claims (3)

[Claims] 1. A compressor whose rotation speed is controlled by a power converter, a current detector for detecting a primary side current of the compressor, and a current for A / D converting a primary current value obtained by the current detector. A detection circuit, an excitation current calculator that calculates an excitation current from a secondary magnetic flux command, a torque current calculator that calculates a torque current from the output of the current detection circuit and the excitation current of the excitation current calculator, and the torque current A torque estimator B that obtains a torque value from the output of the calculator, and a vector rotator that calculates the primary voltage and the phase angle output to the compressor from the exciting current of the exciting current calculator and the torque current of the torque current calculator. And a slip frequency calculator that calculates a slip angular frequency from the secondary magnetic flux command and the torque current of the torque current calculator, a slip angular frequency of the slip frequency calculator, and a desired rotation angular frequency. An adder that calculates the actual rotational angular frequency that is the current rotational speed of the compressor from a set value, a shell discharge temperature detector that detects the shell discharge temperature of the compressor, and a shell discharge pressure of the compressor Shell discharge pressure detector, shell suction temperature detector for detecting the shell suction temperature of the compressor, shell suction pressure detector for detecting the shell suction pressure, the shell discharge pressure detector and the shell discharge temperature An enthalpy calculator that calculates the work of the compressor from the output signals of the detector, the shell suction pressure detector, and the shell suction temperature detector, and the estimated torque value of the compressor based on the output signal from the enthalpy calculator , A comparator that calculates the difference between the output signal of the torque estimator A and the output signal of the torque estimator B, and the output signal of the comparator. And a primary resistance identifier for identifying a primary resistance necessary for calculation in the vector rotator, and by changing the setting value of the primary resistance so that the difference between the comparators becomes zero, the effect of temperature change An air conditioner that is designed to correct the primary resistance that receives. 2. A compressor whose rotation speed is controlled by a power converter, a current detector for detecting a primary side current of the compressor, and a current for A / D converting a primary current value obtained by the current detector. A detection circuit, an excitation current calculator that calculates an excitation current from a secondary magnetic flux command, a torque current calculator that calculates a torque current from the output of the current detection circuit and the excitation current of the excitation current calculator, and the torque current A torque estimator B for obtaining a torque value from the output of a calculator, and a vector rotator for calculating a primary voltage and a phase angle output to the compressor from the exciting current of the exciting current calculator and the torque current of the torque current calculator. A slip frequency calculator that calculates a slip angular frequency from the secondary magnetic flux command and the torque current of the torque current calculator, and a slip angular frequency of the slip frequency calculator and a desired rotation speed Adder, a shell discharge temperature detector for detecting the shell discharge temperature of the compressor, a shell suction pressure detector for detecting the shell suction pressure of the compressor, and a shell suction temperature detector for detecting the shell suction temperature. An enthalpy calculator that calculates the work of the compressor from the output signals of the shell discharge temperature detector, the shell suction pressure detector, and the shell suction temperature detector, and the output signal from the enthalpy calculator. A torque estimator A for calculating an estimated torque value of the compressor, a comparator for calculating a difference between an output signal of the torque estimator A and an output signal of the torque estimator B, and the vector from the output signal of the comparator. A primary resistance identifier for identifying a primary resistance necessary for calculation in the rotator, and changing the set value of the primary resistance so that the difference between the comparators becomes zero. The air conditioning apparatus that corrects the primary resistance affected by temperature changes. 3. A compressor whose rotation speed is controlled by a power converter, a current detector for detecting the primary side current of the compressor, and a current for A / D converting the primary current value obtained by the current detector. A detection circuit, an excitation current calculator that calculates an excitation current from a secondary magnetic flux command, a torque current calculator that calculates a torque current from the output of the current detection circuit and the excitation current of the excitation current calculator, and the torque current A torque estimator B that obtains a torque value from the output of the calculator, and a vector rotator that calculates the primary voltage and the phase angle output to the compressor from the exciting current of the exciting current calculator and the torque current of the torque current calculator. And a slip frequency calculator that calculates a slip angular frequency from the secondary magnetic flux command and the torque current of the torque current calculator, a slip angular frequency of the slip frequency calculator, and a desired rotation angular frequency. An adder that calculates the actual rotational angular frequency that is the current rotational speed of the compressor from a set value, a shell discharge temperature detector that detects the shell discharge temperature of the compressor, and a shell discharge pressure of the compressor Shell discharge pressure detector, shell suction temperature detector for detecting the shell suction temperature of the compressor, output signals of the shell discharge temperature detector, the shell discharge pressure detector and the shell suction temperature detector, respectively. From the enthalpy calculator, a torque estimator A that calculates a torque estimated value of the compressor based on an output signal from the enthalpy calculator, an output signal of the torque estimator A, and the torque estimation A comparator for calculating the difference between the output signals of the device B and a primary resistance identifier for identifying the primary resistance required for the calculation in the vector rotator from the output signal of the comparator. , By changing the set value of primary resistance so as to zero the difference in the comparator, an air conditioning apparatus which is adapted to correct the primary resistance affected by temperature changes.