JP2005210793A - Inverter controller, inverter control method, sealed compressor, and freezing air-conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverter controller which is free of restriction on operation in such a way that it needs to be kept operating continuously with a certain number of revolutions so as to accurately detect its mechanical position, by enabling it to quickly and accurately detect the mechanical position even if it is immediately after start where load torque pulsation is small or even in a region where the number of revolutions is relatively high. <P>SOLUTION: This inverter controller is equipped with a load torque reference position estimating part which estimates a reference torque reference position, using a parameter in correlation with load torque, a load torque reference position estimate which is estimated by the load torque reference position estimating part, a load torque reference position deciding part which decides the load torque reference position by the stipulated relation of the mechanical position of a load element, and a load torque compensating pattern calculating part which compensates the load torque ripple per revolution. This compensates the output voltage or currents of an inverter, using a load torque compensating pattern which is calculated in the load torque compensating pattern calculating part, on the basis of the load torque reference position decided by the load torque reference position deciding part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a permanent magnet synchronous motor that suppresses vibration of a compressor when driving a single rotary compressor or the like that is mounted on a refrigeration air conditioner such as a refrigerator or an air conditioner and whose load torque varies periodically. The present invention relates to an inverter control device.

  In general, a system is used in which an electric motor for a compressor such as a refrigerator or an air conditioner is variably controlled by an inverter. And when a compressor is a single rotary type, since a compression element and an electrically-driven element are directly attached to an airtight container, since a vibration inside a compressor cannot be suppressed, a vibration of a compressor often becomes a problem. The vibrations of the single rotary compressor are caused by periodic load fluctuations, and mainly the vibration components in the rotational direction.

  Torque control is used as a method for reducing such compressor vibration. For example, in the case of a four-pole synchronous motor, utilizing the characteristic that the vibration of the compressor has the characteristic that the compression volume is minimized in the compression stroke, that is, the load applied to the synchronous motor is maximized at the maximum time. Using the filter circuit from the armature winding terminal voltage of the synchronous motor, the position detection signal of the rotor position detection circuit that forms the position detection signal corresponding to the rotor position and the detection signal of the vibration of the compressor are used. Determine the mechanical position. Then, the stored load torque is read according to the mechanical position of the rotor, and the torque of the electric motor is output based on the read data (see, for example, Patent Document 1).

However, in the configuration as described above, a compressor vibration detector is required to control the torque of the four-pole synchronous motor, which increases the cost. Therefore, in order to realize torque control of an inexpensive 4-pole synchronous motor that does not require a compressor vibration detector, a 4-pole motor that drives a load, an inverter that supplies AC power to the synchronous motor, A rotor position detection circuit that detects the rotor position of the motor, a rotation speed detection circuit that calculates the rotor speed based on the output of the rotor position detection circuit, and a torque that stores a load torque pattern per rotation of the synchronous motor The pattern memory unit, the mechanical position determining circuit for determining the mechanical position of the rotor based on the output of the rotational speed detecting circuit, the output of the rotor position detecting circuit, and the output of the mechanical position determining circuit in advance in the torque pattern storing unit A torque controller that reads the stored torque pattern and controls the output torque of the synchronous motor based on the read torque pattern; Compressor motor control device is known which includes (e.g., see Patent Document 2).
JP-A 61-4492 JP-A-6-90588

  The conventional compressor motor control device determines the mechanical position of the rotor based on the rotational speed, so the mechanical position is accurately set immediately after startup with a small load torque pulsation or in a region where the rotational speed is relatively high. There is a problem that it takes time to detect. Therefore, in order to accurately detect the mechanical position in a region where the load torque pulsation is small, it is possible to have an operation restriction that the operation must be continuously performed at a certain rotation speed, for example, for compressor control of an air conditioner. When used, there is a problem that the temperature management control is affected.

  In addition, when the load is a compressor load, the load torque pulsation becomes large in order to accurately detect the mechanical position when the positional relationship between the compressor mechanical position and the stator and rotor of the synchronous motor is not specified. If it is necessary to determine the mechanical position in the rotation range, and vibration or noise at that time becomes a problem, control without torque control giving up the determination of the worst mechanical position, and increase the minimum number of rotations. There was also the problem of having to.

  The present invention has been made to solve the above-mentioned problems, and a first object is to quickly and accurately determine the mechanical position even immediately after startup with a small load torque pulsation or in a region where the rotational speed is relatively high. Inverter control device, inverter control method, hermetic compressor, and refrigeration and air conditioning without operation restrictions that must be continuously operated at a certain rotational speed in order to detect the mechanical position accurately Is to get the equipment.

  In addition, the second object is to provide an inverter that can quickly and accurately detect the mechanical position even immediately after the start-up where the load torque pulsation is small or in a region where the rotational speed is relatively high, thereby quickly suppressing vibration and noise against the load torque pulsation. To obtain a control device, an inverter control method, a hermetic compressor, and a refrigeration air conditioner.

  The inverter control device according to the present invention drives a load element whose load torque fluctuates periodically, has a number of poles of 2n poles (n is an integer of 2 or more), and the position of the load element relative to the mechanical position. A load torque reference position estimation unit for estimating a load torque reference position using a parameter correlated with the load torque in an inverter control device that controls a motor with a defined relationship by three-phase sine wave drive, and a load torque reference position A load torque reference position determination unit that determines a load torque reference position based on a prescribed relationship between a load torque reference position estimated value estimated by the estimation unit and a mechanical position of a load element, and load torque compensation that compensates for load torque fluctuation per rotation A pattern calculation unit, and the load torque compensation pattern calculation unit calculates the load torque reference position determined by the load torque reference position determination unit. By using the load torque compensation pattern, and correcting the output voltage or current of the inverter.

  The inverter control device according to the present invention drives a load element whose load torque fluctuates periodically, has a number of poles of 2n poles (n is an integer of 2 or more), and the position of the load element relative to the mechanical position. A load torque reference position estimation unit for estimating a load torque reference position using a parameter correlated with the load torque in an inverter control device that controls a motor with a defined relationship by three-phase sine wave drive, and a load torque reference position A load torque reference position determination unit that determines a load torque reference position based on a prescribed relationship between a load torque reference position estimated value estimated by the estimation unit and a mechanical position of a load element, and load torque compensation that compensates for load torque fluctuation per rotation A pattern calculation unit, and the load torque compensation pattern calculation unit calculates the load torque reference position determined by the load torque reference position determination unit. Since the output voltage or current of the inverter is corrected using the load torque compensation pattern, the mechanical position can be detected quickly and accurately even immediately after startup with a small load torque pulsation or in a region where the rotational speed is relatively high. Thus, it is possible to obtain an inverter control device that does not have an operation restriction that must be continuously operated at a certain rotational speed in order to accurately detect the mechanical position. Further, vibration and noise with respect to load torque pulsation can be suppressed quickly and accurately.

Embodiment 1 FIG.
FIG. 1 to FIG. 14 are diagrams showing Embodiment 1, FIG. 1 is a schematic block diagram of an inverter control device, FIG. 2 is a detailed block diagram of the inverter control device, and FIG. 3 is a permanent magnet synchronous motor of a single rotary compressor and FIG. 4 is a block diagram of a load torque reference position estimation unit, FIG. 5 is a schematic block diagram of another inverter control device, FIG. 6 is a detailed block diagram of another inverter control device, and FIG. 7 is a load torque. FIG. 8 is a flowchart of the load torque reference position determination unit, FIG. 9 is a flowchart of the load torque compensation pattern calculation unit and the excitation current command value calculation unit, and FIG. 10 is the execution frequency fd and load. FIG. 11 is a diagram showing the relationship between the torque compensation amount amplitude Δiγ *, FIG. 11 is a diagram showing the relationship between the execution frequency fd and the load torque reference position correction amount θadj, and FIG. 12 is the execution frequency fd. FIG. 13 is a timing chart of the excitation current command value calculation unit, and FIG. 14 is a vector diagram of a general permanent magnet synchronous motor according to the first embodiment. is there.

  As shown in FIG. 1, the inverter control device calculates the U-phase current value and the V-phase current value detected by the inverter 2 connected to the DC power source 1 that drives the compressor 3 and the current detection units 4 a and 4 b. The inverter control unit 5 outputs a PWM (pulse width modulation) signal to the inverter 2 so that the execution frequency fd becomes the frequency command value f *.

The configuration of the inverter control device will be described in detail with reference to FIG.
The inverter 2 is a 180-degree sine wave energization type inverter that drives the compressor 3 by converting the DC power source 1 into a three-phase pseudo sine wave. D6 is provided.

  The compressor 3 is a hermetic compressor, and includes a permanent magnet synchronous motor 3a as an example of an electric motor, and a compressor 3b (an example of a load element whose load torque fluctuates periodically) serving as a load thereof. It is. As shown in FIG. 3, the permanent magnet synchronous motor 3 a is fixed directly in the shell (sealed container) of the compressor 3 and has a three-phase Y-shaped stator (stator) composed of a U phase, a V phase, and a W phase. ) And a rotor (rotor) having a 6-pole number in which a magnet (permanent magnet) is arranged on the outer periphery of the shaft (rotary shaft). However, the motor is not limited to a permanent magnet synchronous motor. Further, the load element whose load torque varies periodically is not limited to the compressor of the compressor. Furthermore, the hermetic compressor is not limited to a single rotary compressor.

  The compression unit 3b sucks, compresses and discharges the refrigerant gas when a rolling piston fitted to an eccentric portion of the shaft (rotating shaft) revolves in the cylinder. In FIG. 3, the rolling piston is located at the top dead center.

  Here, the positional relationship between the compressor mechanical position of the compression unit 3b and the stator and rotor of the permanent magnet synchronous motor 3a is manufactured in a defined positional relationship.

  The inverter control unit 5 determines the execution frequency fd based on the voltage value of the DC power supply 1 (hereinafter referred to as bus voltage value) and the U-phase current value and V-phase current value detected by the current detection units 4a and 4b. A PWM signal is output to the inverter 2 so that the frequency command value f * is obtained, and the transistors TR1 to TR6 are controlled to be turned on / off.

  In this embodiment, the U-phase current value and the V-phase current value are detected. However, the detected current value by the current detection units 4a and 4b is the current value of any two-phase current ( For example, the same result can be obtained by detecting a U-phase current value and a W-phase current value.

  The inverter control unit 5 includes the following three-phase / two-phase coordinate conversion unit 6, frequency compensation unit 7, execution frequency calculation unit 8, primary frequency calculation unit 9, electrical angle angle calculation unit 10, mechanical angle angle calculation unit 11, Load torque reference position estimation unit 12, load torque reference position determination unit 13, load torque compensation pattern calculation unit 14, excitation current command value calculation unit 15, output voltage command value calculation unit 16, two-phase / three-phase coordinate conversion unit 17, And a PWM signal generation unit 18. The inverter control unit 5 can be realized by a microprocessor, for example. The processing timing of each part is assumed to be performed for each carrier period of the PWM signal, for example.

  The three-phase / two-phase coordinate conversion unit 6 uses the electrical angle angle θe to convert the current values detected by the current detection units 4a and 4b into an excitation current component (γ-axis current iγ) and a torque current component (δ-axis current iδ). Is converted into a current value on the γ-δ axis expressed by

  The frequency compensator 7 is a δ-axis current filter obtained by calculating the δ-axis current obtained by the three-phase / 2-phase coordinate converter 6 and the first-order lag filter operation (for example, the filter time constant is 100 ms). The frequency compensation amount fh is obtained by multiplying the difference (harmonic component) from the value by a gain Km (for example, Km = 2).

  The execution frequency calculation unit 8 brings the execution frequency fd closer to the frequency command value f * given from outside by Δf.

  The primary frequency calculation unit 9 compensates the execution frequency fd using the frequency compensation amount fh obtained by the frequency compensation unit 7 to obtain the primary frequency f1. Thereby, even when load torque fluctuates rapidly, generated torque can be made to follow.

  The electrical angle angle calculator 10 integrates the primary frequency f1 that is the compensated frequency command value to obtain the electrical angle angle θe.

  The mechanical angle angle calculation unit 11 obtains the mechanical angle angle θm based on a value obtained by dividing the electrical angle angle θe calculated by the electrical angle angle calculation unit 10 by the number of pole pairs pp (in the case of 6 poles, pp = 3).

  The load torque reference position estimation unit 12 obtains the phase of the peak value of the primary frequency component of the δ-axis current from the mechanical angle θm and the δ-axis current iδ, and uses that value as the load torque reference position estimate. .

  The load torque reference position estimation unit 12 of the present embodiment will be described with reference to FIG. FIG. 4 is a block diagram of the torque reference position estimation unit. The sin component extraction unit 12a extracts a sin component using the δ-axis current and the mechanical angle. The cos component extraction unit 12b extracts the cos component using the δ-axis current and the mechanical angle. The filter unit 12c multiplies the sin component of the δ-axis current extracted by the sin component extraction unit 12a by a first-order lag filter (for example, the filter time constant is 1 s). The filter unit 12d multiplies the cos component of the δ-axis current extracted by the cos component extraction unit 12b by a first-order lag filter (for example, the filter time constant is 1 s).

Using the filter value of the sine component of the δ-axis current obtained from the filter unit 12c and the filter value of the cosine component of the δ-axis current obtained from the filter unit 12d, the tan ^-1 calculation unit 12e uses the tan ^-1 calculation. By doing so, the phase of the peak value of the primary frequency component of the δ-axis current can be obtained. This value is the load torque reference position estimated value.

  In this embodiment, the torque reference position estimated value is obtained based on the δ-axis current value that has a strong correlation with the load torque, but other parameters (for example, the δ-axis voltage value) that have a correlation with the load torque are obtained. It may be used.

  The load torque reference position determination unit 13 determines the load torque reference position θpx based on the load torque reference position estimated value θp obtained by the load torque reference position estimation unit 12.

  The load torque compensation pattern calculation unit 14 performs load based on the execution frequency fd obtained by the execution frequency calculation unit 8, the load torque reference position determination value θpx obtained by the load torque reference position determination unit 13, and the mechanical angle θm. A torque compensation pattern iγ * (2) is calculated.

  The excitation current command value calculation unit 15 includes a load torque compensation pattern iγ * (2) obtained by the load torque compensation pattern calculation unit 14 and an excitation current command value reference value iγ * (1) described later corresponding to the execution frequency fd. Thus, the excitation current command value iγ * is obtained.

  The output voltage command value calculation unit 16 includes a primary frequency f1 obtained by the primary frequency calculation unit 9, an excitation current command value iγ * obtained by the excitation current command value calculation unit 15, and a three-phase / two-phase coordinate conversion unit. The γ-axis voltage command value Vγ * and the δ-axis voltage command value Vδ * are obtained from the excitation current iγ and the δ-axis current iδ obtained in step 6.

  The two-phase / three-phase coordinate conversion unit 17 includes the γ-axis voltage command value Vγ * and the δ-axis voltage command value Vδ * obtained by the output voltage command value calculation unit 16, and the electric angle obtained by the electrical angle angle calculation unit 10. The voltage is converted into voltage command values Vu *, Vv *, and Vw * in a three-phase coordinate system according to the angle θe.

  The PWM signal generator 18 turns on / off the transistors TR1 to TR6 of the inverter 2 based on the three-phase voltage command values Vu *, Vv *, Vw * obtained by the two-phase / three-phase coordinate converter 17 and the bus voltage value. A PWM signal for control is generated. The inverter 2 is controlled based on the PWM signal, and the DC power source 1 is converted into a three-phase pseudo sine wave to drive the compressor 3.

  In the above embodiment, the phase current is detected by detecting the two phases, but the current flowing through the DC power source 1 (hereinafter referred to as the bus current) is detected by the current detector 4c as shown in FIGS. A similar result can be obtained even if the phase current converter 19 uses the value obtained by converting the bus current value to each phase current value iu, iv, iw using the PWM signal timing of the PWM signal generator 18. it can.

  Next, the operation will be described with reference to a timing chart in the load torque reference position determination unit 13 of FIG. 7, (a) is a load torque, (b) is a δ-axis current iδ, (c) is a primary frequency component of the δ-axis current, (d) is an electrical angle θe, and (e) is a mechanical angle θm. It is.

  There is a correlation between the load torque pulsation and the primary frequency component of the δ-axis current, and the phase of the peak value of the primary frequency component of the δ-axis current can be used as the load torque reference position. However, in the case of a 6-pole motor, there are three patterns as shown in FIG. 7E at the timing when the mechanical angle θm is set to 0 using the electrical angle θe.

  Therefore, the load torque reference position determination method will be described with reference to the flowchart in the load torque reference position determination unit 13 of FIG.

  STEP 1 is a process for determining whether or not the load torque reference position determination value θpx has been determined. If θpx is determined, the processes of STEP 2 to STEP 9 are not performed.

  If θpx is not fixed, the load torque reference position estimation calculation process in STEP 2 is performed, and the phase of the peak value of the primary frequency component of the δ-axis current (= load torque reference position estimated value θp) is obtained. STEP 3 is a condition for performing load torque reference position determination calculation. In this embodiment, load torque reference position determination calculation processing is performed when the execution frequency is 60 [rps] or higher. When the execution frequency is less than 60 [rps], the load torque reference position determination process is not performed.

  STEP 4 to STEP 8 are processes for determining the load torque reference position θpx. When the load torque reference position estimated value θp is 55 ° or more and less than 175 ° (STEP 4), the load torque reference position determination value θpx is 115 ° (STEP 5). When the estimated load torque reference position value θp is not less than 175 ° and less than 295 ° (STEP 6), the load torque reference position determination value θpx is set to 235 ° (STEP 7). Otherwise, θpx is 355 ° (STEP 8). And STEP 9 is a process indicating that θpx has been determined.

  In the flow chart of the load torque compensation pattern calculation unit 14 and the excitation current command value calculation unit 15 in FIG. 9, STEP 10 is based on a table of execution frequency fd and load torque compensation amount amplitude ΔIγ * (hereinafter referred to as fd−ΔIγ * table). , Fd corresponding to ΔIγ *. An example of the fd-ΔIγ * table is shown in FIG.

  STEP 11 is a process of reading out θadj corresponding to fd from a table of execution frequency fd and load torque reference position correction amount θadj (hereinafter referred to as fd−θadj table). An example of the fd-θadj table is shown in FIG.

STEP 12 is a process for calculating the load torque compensation pattern iγ * (2) according to the equation (1).
iγ * (2) = ΔIγ * × sin {θm− (θpx + θadj)} (1)

  STEP 13 is a process of reading iγ * (1) corresponding to fd from a table of execution frequency fd and excitation current reference command value iγ * (1) (hereinafter referred to as fd-iγ * (1) table). An example of the fd-iγ * (1) table is shown in FIG.

  STEP 14 obtains the excitation current command value iγ * from the excitation current reference command value iγ * (1) obtained in STEP 13 and the load torque compensation pattern iγ * (2) obtained in STEP 12.

  In the timing chart of the excitation current command value calculation unit 15 in FIG. 13, (a) is the load torque, (b) is the primary frequency component of the δ-axis current, (c) is the mechanical angle θm, and (d) is the excitation. The current command value iγ *, (e) is the generated torque. 9 is performed, the excitation current command value iγ * is generated, and the generated torque corresponding to the load torque pattern is obtained.

  Here, in this embodiment, since the γ-δ axis is used as the coordinate system instead of the dq axis, the relationship between the dq axis coordinate system and the γ-δ axis coordinate system will be described. The voltage equation in the dq axis coordinates of the permanent magnet synchronous motor is generally given by equation (2). In the dq-axis coordinate system, the d-axis is defined as the direction of the N pole of the permanent magnet rotor, and the axis that forms a phase advanced by 90 ° in electrical angle from the d-axis to the rotation direction is defined as the q-axis.

  In Equation (2), Vd is the d-axis voltage of the permanent magnet synchronous motor, Vq is the q axis voltage of the permanent magnet synchronous motor, R is the resistance value per phase of the permanent magnet synchronous motor, and Ld is d of the permanent magnet synchronous motor. The axial inductance, Lq is the q-axis inductance of the permanent magnet synchronous motor, Φf is the induced voltage constant of the permanent magnet synchronous motor, id is the d-axis current of the permanent magnet synchronous motor, iq is the q-axis current of the permanent magnet synchronous motor, and ω is permanent The angular speed of the magnet synchronous motor, p represents a differential operator with respect to time t.

  In the vector diagram under a certain operating condition of the permanent magnet synchronous motor (particularly the embedded magnet type synchronous motor) of FIG. 14, the horizontal axis represents the γ-axis and the vertical axis represents the δ-axis. Further, the d axis and the q axis are positioned at angles rotated by Δθ with respect to the γ axis and the δ axis, respectively. Here, ΦF is a magnetic flux vector generated by the rotor magnet, and its magnitude is an induced voltage constant Φf, which is located on the d-axis.

  Lγ · iγ is a γ-axis component of the stator magnetic flux, Lδ · iδ is a δ-axis component of the stator magnetic flux, and Φ0 is the stator magnetic flux (Lγ · iγ, Lδ · iδ) and the rotor magnetic flux (ΦF). It is a composite magnetic flux vector. Here, Lγ is the γ-axis inductance of the permanent magnet synchronous motor, and Lδ is the δ-axis inductance of the permanent magnet synchronous motor.

  Further, ω1 · Φ0 is a voltage vector generated by the combined magnetic flux, R · Ia is a voltage vector generated by the resistance of the motor, Va is a combined vector thereof, and is a voltage vector applied to the permanent magnet synchronous motor. Here, ω1 is a value obtained by converting the primary frequency f1 into an angular velocity, and Ia is a combined vector of the excitation current iγ and the δ-axis current iδ. The γ-axis component of Va is the γ-axis voltage Vγ, and the δ-axis component is the δ-axis voltage Vδ.

  Here, the phase difference Δθ between the dq axis and the γ-δ axis is approximated as Δθ≈0, and the inductance of each axis is handled as Lγ≈Ld and Lδ≈Lq. The load can be reduced. For example, a microcomputer with low specifications can be used, and the degree of freedom in selecting a microcomputer is increased. However, if it is necessary to improve the control accuracy, Δθ may be predicted and controlled.

  As described above, the positional relationship between the compressor mechanical position (mechanical position) of the compressor 3 and the stator and rotor of the permanent magnet synchronous motor 3a, which is a typical example of a single rotary compressor, is defined and correlated with the load torque. A load torque reference position estimation unit 12 that estimates a load torque reference position using a δ-axis current or a δ-axis voltage that are related parameters, a load torque reference position estimation value estimated by the load torque reference position estimation unit 12, and compression A load torque reference position determining unit 13 that determines a load torque reference position based on a prescribed relationship between mechanical and mechanical positions, and a load torque compensation pattern calculating unit 14 that compensates for load torque fluctuations per rotation are provided. Using the load torque compensation pattern calculated by the load torque compensation pattern calculation unit 14 based on the load torque reference position determined by Since the output voltage or current of the inverter 2 is corrected by controlling the excitation current command value, the load torque reference position can be determined quickly and accurately, and the generated torque that follows the load torque pattern is generated. Speed fluctuation due to load torque fluctuation during one rotation can be quickly suppressed, and vibration and noise can be suppressed.

  If a δ-axis current having a strong correlation with the load torque is used as a parameter having a correlation with the load torque, the load torque reference position can be determined more quickly and accurately, leading to early vibration and noise suppression. .

  Also, by making the load torque compensation pattern sinusoidal, the followability of the load torque will be inferior. However, if the load torque pattern is followed too much, it will be easier to enter overcurrent cutoff protection to protect the inverter element. Can be solved. Further, it is not necessary to hold the load torque pattern, and the development load for determining the load torque pattern can be reduced.

  In addition, by correcting the load torque reference position determined by the load torque reference position with a parameter (for example, δ-axis current) that can detect the execution frequency or the load state, control that follows the load torque pattern can be performed, and vibration and Noise can be suppressed.

  Furthermore, if the load torque reference position is corrected by combining the execution frequency and a parameter (for example, δ-axis current) that can detect the load state, vibration and noise can be further suppressed.

  Further, by correcting the load torque compensation pattern with a parameter (for example, the δ-axis current) that can detect the execution frequency or the load state, control following the load torque pattern can be performed, and vibration and noise can be suppressed.

  Furthermore, if the load torque compensation pattern is corrected by combining the execution frequency and a parameter (for example, the δ-axis current) that can detect the load state, vibration and noise can be further suppressed.

  In addition, the load torque reference position determination unit 13 determines the load torque reference position only once after the inverter is started, holds the load torque reference position, and thereafter performs load torque reference position estimation processing and load torque reference position determination processing. By not doing so, the calculation load in the inverter control unit 5 can be reduced, and for example, it is possible to cope with an inexpensive microcomputer.

  Further, by setting the determination timing of the load torque reference position by the load torque reference position determination unit 13 at the time of high rotation (for example, when the execution frequency is 60 [rps] or more), vibration resonance existing in the low rotation region is avoided. Vibration and noise can be suppressed.

  In this embodiment, the determination timing of the load torque reference position by the load torque reference position determination unit 13 is set at the time of high rotation (for example, when the execution frequency is 60 [rps] or more). For example, speed fluctuation accompanying load torque fluctuation during one rotation can be suppressed immediately after startup, and vibration and noise can be suppressed.

Embodiment 2. FIG.
15 to 19 are diagrams showing the second embodiment, FIG. 15 is a block diagram of the inverter control device, FIG. 16 is a flowchart of the load torque compensation pattern calculation unit, and FIG. 17 is an execution frequency fd and load torque compensation amount amplitude. FIG. 18 is a diagram illustrating the relationship between Δfh, FIG. 18 is a diagram illustrating the relationship between the execution frequency fd and the load torque reference position correction amount θadj ′, and FIG. 19 is a timing chart of the primary frequency calculation unit.

  In FIG. 15, the same parts as those in FIG. Hereinafter, the changed configuration will be described.

  In the first embodiment, the output voltage or current of the inverter 2 is corrected by controlling the excitation current command value. However, in this embodiment, the output voltage or current of the inverter 2 is controlled by controlling the frequency. Correct.

  In FIG. 15, the primary frequency calculation unit 9 ′ is executed by the frequency compensation amount fh obtained by the frequency compensation unit 7 and the load torque compensation pattern fh (2) obtained by the load torque compensation pattern calculation unit 14 ′. The frequency fd is compensated to obtain the primary frequency f1.

  The load torque compensation pattern calculation unit 14 ′ performs load based on the execution frequency fd obtained from the execution frequency calculation unit 8, the load torque reference position determination value θpx obtained by the load torque reference position determination unit 13, and the mechanical angle θm. A torque compensation pattern fh (2) is calculated.

  The excitation current command value calculation unit 15 ′ obtains the excitation current command value iγ * based on the execution frequency fd obtained by the execution frequency calculation unit 8.

  Next, the operation will be described with reference to the flowchart of the load torque compensation pattern calculation unit 14 'in FIG. In FIG. 16, STEP 15 is a process of reading Δfh corresponding to fd from a table of execution frequency fd and load torque compensation amount amplitude Δfh (hereinafter referred to as fd−Δfh table). An example of the fd-Δfh table is shown in FIG.

  STEP 16 is a process for reading θadj ′ corresponding to fd from a table of execution frequency fd and load torque reference position correction amount θadj ′ (hereinafter referred to as fd−θadj ′ table). An example of the fd-θadj ′ table is shown in FIG.

STEP 17 is a process for calculating the load torque compensation pattern fh (2) according to the equation (3).
fh (2) = Δfh × sin {θm− (θpx + θadj ′)} (3)

  In the timing chart of the primary frequency calculation unit 9 ′ in FIG. 19, (a) is the load torque, (b) is the primary frequency component of the δ-axis current, (c) is the mechanical angle θm, and (d) is the primary frequency. f1 and (e) are generated torques. By performing the processing of STEPs 15 to 17 in FIG. 16, the load torque compensation pattern fh (2) is generated, and the generated torque corresponding to the load torque pattern is obtained.

  As described above, the positional relationship between the compressor mechanical position (mechanical position) of the compressor 3 and the stator and rotor of the permanent magnet synchronous motor 3a, which is a typical example of a single rotary compressor, is defined and correlated with the load torque. A load torque reference position estimation unit 12 that estimates a load torque reference position using a δ-axis current or a δ-axis voltage that are related parameters, a load torque reference position estimation value estimated by the load torque reference position estimation unit 12, and compression A load torque reference position determining unit 13 for determining a load torque reference position based on a prescribed relationship of mechanical mechanism positions, and a load torque compensation pattern calculating unit 14 ′ for compensating for a load torque fluctuation per one rotation. 13 using the load torque compensation pattern calculated by the load torque compensation pattern calculation unit 14 ′ based on the load torque reference position determined by 13. Since the output voltage or current of the inverter 2 is corrected by controlling the execution frequency, the load torque reference position can be determined quickly and accurately, and the generated torque following the load torque pattern is generated. Speed fluctuation due to load torque fluctuation during one rotation can be quickly suppressed, and vibration and noise can be suppressed.

  Also, by making the load torque compensation pattern sinusoidal, the followability of the load torque will be inferior. However, if the load torque pattern is followed too much, it will be easier to enter overcurrent cutoff protection to protect the inverter element. Can be solved. Further, it is not necessary to hold the load torque pattern, and the development load for determining the load torque pattern can be reduced.

  In addition, by correcting the load torque reference position determined by the load torque reference position with a parameter (for example, δ-axis current) that can detect the execution frequency or the load state, control that follows the load torque pattern can be performed, and vibration and Noise can be suppressed.

  Furthermore, if the load torque reference position is corrected by combining the execution frequency and a parameter (for example, δ-axis current) that can detect the load state, vibration and noise can be further suppressed.

  Further, by correcting the load torque compensation pattern with a parameter (for example, the δ-axis current) that can detect the execution frequency or the load state, control following the load torque pattern can be performed, and vibration and noise can be suppressed.

  Furthermore, if the load torque compensation pattern is corrected by combining the execution frequency and a parameter (for example, the δ-axis current) that can detect the load state, vibration and noise can be further suppressed.

  In addition, the load torque reference position determination unit 13 determines the load torque reference position only once after the inverter is started, holds the load torque reference position, and thereafter performs load torque reference position estimation processing and load torque reference position determination processing. By not doing so, the calculation load in the inverter control unit 5 can be reduced, and for example, it is possible to cope with an inexpensive microcomputer.

  Further, by setting the determination timing of the load torque reference position by the load torque reference position determination unit 13 at the time of high rotation (for example, when the execution frequency is 60 [rps] or more), vibration resonance existing in the low rotation region is avoided. Vibration and noise can be suppressed.

  In this embodiment, the determination timing of the load torque reference position by the load torque reference position determination unit 13 is set at the time of high rotation (for example, when the execution frequency is 60 [rps] or more). For example, speed fluctuation accompanying load torque fluctuation during one rotation can be suppressed immediately after startup, and vibration and noise can be suppressed.

Embodiment 3 FIG.
20 to 22 are diagrams showing the third embodiment, FIG. 20 is a longitudinal sectional view of a single rotary compressor, and FIG. 21 is a measurement method for measuring pipe stress by attaching an accelerometer to a suction pipe with respect to the single rotary compressor. FIG. 22 is a diagram showing the measurement results of the pipe stress in the suction pipe portion of the single rotary compressor.

  The single-rotary compressor was actually driven using the inverter control device shown in the first or second embodiment, and the vibration suppression effect of torque control was confirmed. The results will be described below.

  The hermetic compressor used in the test is a single-cylinder single rotary compressor 40 as shown in FIG. 20, and the electric motor 41 accommodated in the hermetic container 43 together with the compression unit 42 is used in the first embodiment or the first embodiment. The permanent magnet synchronous motor shown in Embodiment 2 was used.

  In the vibration measuring method of the single rotary compressor 40, as shown in FIG. 21, an acceleration pickup is installed in the suction pipe near the suction muffler connected to the sealed container 43. The output from the accelerometer was input to the frequency analyzer through an amplifier, the primary component was extracted, and the pipe stress was measured.

The measurement results are shown in FIG. In the figure, the horizontal axis represents the operating frequency [S ⁻¹ ] of the single rotary compressor 40 and the vertical axis represents the pipe stress [G × 10 ⁻³ ]. As shown in the figure, a remarkable vibration suppression effect by the torque control of the inverter control device shown in the first embodiment or the second embodiment was confirmed.

Embodiment 4 FIG.
FIGS. 23 to 26 are diagrams showing Embodiment 4, FIG. 23 is a front view of an outdoor unit of an air conditioner, FIG. 24 is a plan view thereof, and FIG. 25 is a method of measuring floor excitation force of the outdoor unit of the air conditioner. FIG. 26 is a diagram showing a result of measuring the floor excitation force of the outdoor unit of the air conditioner.

  In Embodiment 3, the inverter control device shown in Embodiment 1 or Embodiment 2 was used to actually drive the single rotary compressor, and the vibration suppression effect of torque control was confirmed. The floor excitation force of the outdoor unit of an air conditioner using a single rotary compressor was also measured.

  As shown in FIGS. 23 and 24, the indoor unit 50 of the air conditioner includes the single rotary compressor 40, the heat exchanger, the blower, the electrical component room, and the like described in the third embodiment.

  As shown in FIG. 25, the floor excitation force of the indoor unit 50 of the air conditioner was measured by using a sensor to measure the floor excitation force at four points on the lower surface support base of the indoor unit 50 of the air conditioner. The signal from the sensor is taken into the frequency analyzer via the amplifier, and the first order component at each point is extracted. The total excitation force of 4 points was defined as the floor excitation force [gf].

The measurement results are shown in FIG. In the figure, the horizontal axis represents the operating frequency [S ⁻¹ ] of the single rotary compressor 40 and the vertical axis represents the floor excitation force [gf]. As shown in the figure, a remarkable vibration suppression effect by the torque control of the inverter control device shown in the first embodiment or the second embodiment was confirmed.

Embodiment 5 FIG.
FIG. 27 shows the fifth embodiment and is a longitudinal sectional view of the refrigerator. In the figure, the machine room of the refrigerator 60 is located at the lowermost part of the back surface, and a hermetic compressor is installed in the machine room. The refrigerator 60 is used indoors, and it is extremely important to suppress vibration of the hermetic compressor.

  In particular, when a single-cylinder single rotary compressor 40 is used for a hermetic compressor, the unique vibration often becomes a problem. Therefore, by using the single rotary compressor 40 to which the torque control of the inverter control device shown in the first embodiment or the second embodiment is applied for the refrigerator 60, a vibration suppressing effect can be expected.

  In the above description, the air conditioner and the refrigerator are taken as examples, but the same effect can be expected in other refrigeration air conditioners.

FIG. 2 is a diagram showing the first embodiment and is a schematic block diagram of an inverter control device. FIG. 5 is a diagram showing the first embodiment, and is a detailed block diagram of the inverter control device. FIG. 2 is a diagram showing the first embodiment, and is a cross-sectional view of a permanent magnet synchronous motor and a compression unit of a single rotary compressor. FIG. 5 is a diagram illustrating the first embodiment and is a block diagram of a load torque reference position estimation unit. It is a figure which shows Embodiment 1 and is a schematic block diagram of another inverter control apparatus. It is a figure which shows Embodiment 1 and is a detailed block diagram of another inverter control apparatus. FIG. 5 shows the first embodiment, and is a timing chart diagram of a load torque reference position determination unit. FIG. 5 is a diagram illustrating the first embodiment and is a flowchart diagram of a load torque reference position determination unit. FIG. 5 is a diagram showing the first embodiment and is a flowchart diagram of a load torque compensation pattern calculation unit and an excitation current command value calculation unit. FIG. 5 is a diagram illustrating the first embodiment and is a diagram illustrating a relationship between an execution frequency fd and a load torque compensation amount amplitude Δiγ *. FIG. 5 is a diagram illustrating the first embodiment and is a diagram illustrating a relationship between an execution frequency fd and a load torque reference position correction amount θadj. FIG. 5 is a diagram illustrating the first embodiment and is a diagram illustrating a relationship between an execution frequency fd and an excitation current reference command value iγ * (1). FIG. 5 is a diagram illustrating the first embodiment and is a timing chart of an excitation current command value calculation unit. It is a figure which shows Embodiment 1 and is a vector diagram of a general permanent magnet synchronous motor. It is a figure which shows Embodiment 2, and is a block diagram of an inverter control apparatus. FIG. 10 is a diagram illustrating the second embodiment and is a flowchart of a load torque compensation pattern calculation unit. FIG. 10 is a diagram illustrating the second embodiment and is a diagram illustrating a relationship between an execution frequency fd and a load torque compensation amount amplitude Δfh. FIG. 10 is a diagram illustrating the second embodiment and is a diagram illustrating a relationship between an execution frequency fd and a load torque reference position correction amount θadj ′. It is a figure which shows Embodiment 2, and is a timing chart figure of a primary frequency calculating part. It is a figure which shows Embodiment 3, and is a longitudinal cross-sectional view of a single rotary compressor. FIG. 9 is a diagram showing a third embodiment, and is a schematic diagram showing a measurement method for measuring a pipe stress by attaching an acceleration pickup to a suction pipe with respect to a single rotary compressor. It is a figure which shows Embodiment 3, and is a figure which shows the measurement result of the piping stress of the suction pipe part of a single rotary compressor. It is a figure which shows Embodiment 4, and is a front view of the outdoor unit of an air conditioner. It is a figure which shows Embodiment 4, and is a top view of the outdoor unit of an air conditioner. It is a figure which shows Embodiment 4, and is a figure which shows the floor excitation force measuring method of the outdoor unit of an air conditioner. It is a figure which shows Embodiment 4, and is a figure which shows the floor excitation force measurement result of the outdoor unit of an air conditioner. It is a figure which shows Embodiment 5, and is a longitudinal cross-sectional view of a refrigerator.

Explanation of symbols

1 DC power supply, 2 inverter, 3 compressor, 3a permanent magnet synchronous motor, 3b compression unit, 4a, 4b, 4c current detection unit, 5 inverter control unit, 6 3 phase / 2 phase coordinate conversion unit, 7 frequency compensation unit, 8 execution frequency calculation unit, 9, 9 ′ primary frequency calculation unit, 10 electrical angle angle calculation unit, 11 mechanical angle angle calculation unit, 12 load torque reference position estimation unit, 12a sin component extraction unit, 12b cos component extraction unit, 12c , 12d filter unit, 12e tan ^-1 calculation unit, 13 load torque reference position determination unit, 14, 14 'load torque compensation pattern calculation unit, 15, 15' excitation current command value calculation unit, 16 output voltage command value calculation unit, 17 2-phase / 3-phase coordinate conversion unit, 18 PWM signal generation unit, 40 single rotary compressor, 41 electric motor, 42 compression unit, 43 sealed container, 50 indoor unit of air conditioner, 6 Refrigerator.

Claims (14)

Three electric motors that drive a load element whose load torque fluctuates periodically, have 2n poles (n is an integer of 2 or more), and have a positional relationship with the mechanical position of the load element are defined. In the inverter control device controlled by phase sine wave drive,
A load torque reference position estimation unit that estimates a load torque reference position using a parameter correlated with the load torque;
A load torque reference position determining unit that determines a load torque reference position based on a specified relationship between a load torque reference position estimated value estimated by the load torque reference position estimating unit and a mechanical position of the load element;
A load torque compensation pattern calculation unit for compensating for load torque fluctuation per rotation;
And correcting the output voltage or current of the inverter using the load torque compensation pattern calculated by the load torque compensation pattern calculation unit based on the load torque reference position determined by the load torque reference position determination unit An inverter control device characterized by that.   The torque current component obtained by three-phase / 2-phase coordinate conversion of the three-phase sine wave drive output current of the inverter is used as a parameter correlated with the load torque used in the load torque reference position estimation unit. 1. The inverter control device according to 1.   The inverter control device according to claim 1, wherein an output voltage or current of the inverter is corrected by controlling an excitation current command value.   The inverter control device according to claim 1, wherein an output voltage or current of the inverter is corrected by controlling a frequency.   The inverter control device according to claim 1, wherein the load torque compensation pattern is sinusoidal.   The inverter control device according to claim 1, wherein the load torque reference position determined by the load torque reference position determination unit is corrected using a parameter or a combination thereof capable of detecting the frequency or load state of the inverter. .   The inverter control device according to claim 1, wherein the load torque compensation pattern is corrected using a parameter capable of detecting a frequency or a load state of the inverter or a combination thereof.   2. The inverter control device according to claim 1, wherein the load torque reference position determining unit determines the load torque reference position only once after the inverter is started.   The inverter control device according to claim 1, wherein the determination timing by the load torque reference position determination unit is a high rotation time.   The inverter control device according to claim 1, wherein the determination timing by the load torque reference position determination unit is immediately after startup. Three electric motors that drive a load element whose load torque fluctuates periodically, have 2n poles (n is an integer of 2 or more), and have a positional relationship with the mechanical position of the load element are defined. In the inverter control method for controlling by phase sine wave drive,
Estimating a load torque reference position using a parameter correlated with the load torque;
Determining a load torque reference position based on a prescribed relationship between a load torque reference position estimated value estimated by the load torque reference position estimation unit and a mechanical position of the load element;
Calculating a load torque compensation pattern for compensating for load torque fluctuations per rotation;
Correcting the output voltage or current of the inverter using the load torque compensation pattern based on the determined load torque reference position;
An inverter control method comprising: A compression unit provided in the hermetic container and compressing the refrigerant to periodically change the load torque;
An electric motor that drives the compression unit and has a number of poles equal to or greater than 2n poles (n is an integer of 2 or more) in which a positional relationship with the compression unit mechanical position is defined;
An inverter for driving the electric motor with three-phase sine wave energization;
A load torque reference position estimating unit that estimates a load torque reference position using a parameter correlated with the load torque of the compression unit; a load torque reference position estimated value estimated by the load torque reference position estimating unit; and the load element A load torque reference position determining unit that determines a load torque reference position based on a prescribed relationship of mechanical positions, and a load torque compensation pattern calculating unit that compensates for load torque fluctuation per rotation, and determining the load torque reference position An inverter control device that corrects the output voltage or current of the inverter using the load torque compensation pattern calculated by the load torque compensation pattern calculation unit based on the load torque reference position determined by the unit;
A hermetic compressor characterized by comprising   13. The hermetic compressor according to claim 12, wherein the compression section is formed of a single cylinder single rotary type.   A refrigeration air conditioner using the hermetic compressor according to claim 12 in a refrigeration cycle.

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