GB2600095A - A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device - Google Patents
A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device Download PDFInfo
- Publication number
- GB2600095A GB2600095A GB2016333.3A GB202016333A GB2600095A GB 2600095 A GB2600095 A GB 2600095A GB 202016333 A GB202016333 A GB 202016333A GB 2600095 A GB2600095 A GB 2600095A
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- United Kingdom
- Prior art keywords
- computing device
- electronic computing
- phase currents
- high frequency
- permanent magnet
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- 230000001360 synchronised effect Effects 0.000 title claims abstract description 14
- 238000000034 method Methods 0.000 title claims description 42
- 238000002347 injection Methods 0.000 claims abstract description 9
- 239000007924 injection Substances 0.000 claims abstract description 9
- 230000009466 transformation Effects 0.000 claims abstract description 5
- 238000010586 diagram Methods 0.000 description 23
- 230000010355 oscillation Effects 0.000 description 8
- 238000005070 sampling Methods 0.000 description 3
- 230000005284 excitation Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 1
- 230000001550 time effect Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/38—Means for preventing simultaneous conduction of switches
- H02M1/385—Means for preventing simultaneous conduction of switches with means for correcting output voltage deviations introduced by the dead time
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0009—Devices or circuits for detecting current in a converter
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/24—Vector control not involving the use of rotor position or rotor speed sensors
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using DC to AC converters or inverters
- H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using DC to AC converters or inverters with pulse width modulation
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
- H02M7/42—Conversion of DC power input into AC power output without possibility of reversal
- H02M7/44—Conversion of DC power input into AC power output without possibility of reversal by static converters
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
A dead time of a voltage source inverter for an interior permanent magnet synchronous machine (IPMSM) is compensated using an electronic computing device 10. Speed control and position control of the IPMSM are performed using sensorless control with a high frequency injection voltage u*HF by the electronic computing device, wherein a phase current prediction ipred_abc is used for compensating the dead time, wherein the phase current prediction is made depending on fundamental three-phase currents iabc* and high frequency phase currents iHF_abc. The fundamental three-phase currents may be determined depending on current commands (id*, iq*) and/or an estimated rotor electrical position ϑest. The high frequency phase currents may be determined depending on the estimated rotor electrical position ϑest and/or by using a Park's and Clark's transformation. The interior permanent magnet synchronous machine may be used in hybrid or electric vehicle powertrains.
Description
A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device, as well a corresponding electronic computing device
FIELD OF THE INVENTION
[0001] The invention relates to the field of automobiles. More specifically, the invention relates to a method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device, as well as to a corresponding electronic computing device.
BACKGROUND INFORMATION
[0002] An interior permanent magnet synchronous machine (IPMSM) is used widely for example in hybrid or electric vehicle powertrains due to its sturdy rotor structure and high power density. The classic field-oriented control of the IPMSM requires a rotor position and a speed signal, which is usually measured by a speed and position sensor, such as a resolver or an encoder point. The speed and position sensorless control of the IPMSM could improve electrified vehicle robustness by being used as a redundancy when the sensor fails, or totally eliminate the speed and position sensor in the system. For hybrid and electric vehicle powertrains, a speed and position sensorless control method has to be performed in full speed range and with high torque accuracy.
[0003] In the state of the art, two speed and position sensorless control method types are known. The first known type of method is through fundamental excitation, which is based on an electric machine Intrinsic Mode Function (IMF) model, which is also referred to as IMF methods. The second known type of method is through high frequency signal injection, which is also referred to as HFI methods. HFI methods are capable of standstill and ultra-low speed region, while fundamental excitation methods are capable of low to high-speed region. In order to achieve full speed range of operation of sensorless control, both methods have to be implemented and transit smoothly based on electric machine rotor speed.
[0004] To avoid shoot through in voltage source inverters, dead time, a small interval during which both the upper and lower switches in a phase-leg are off, is introduced into the standard pulse width modulation control of the voltage source inverters. This causes a voltage loss from commanded voltage. Depending on the current direction on each phase, dead-time compensation is applied based on the sign of the phase currents.
[0005] CN 109981013 A discloses an identification method of a motor phase current sampling delay time. The method comprises the steps: According to a permanent magnet synchronous motor model, injecting high-frequency voltage signals at a motor control end to obtain a high-frequency voltage equation and simplify the high-frequency voltage equation, selecting to inject the high-frequency voltage signal at ad axis to obtain a high-frequency current signal expression, correcting the high-frequency current signal expression by comprehensively considering the delay time in the motor phase current signal sampling process, and obtaining the motor phase current sampling loop delay time through phase delay phase-locked loop processing.
[0006] CN 108400737 Al provides a dead-zone compensation method and circuit, power electronic equipment and a computer storage medium. The dead-zone compensation method comprises the steps of converting a three-phase voltage of a bus to a voltage vector; and determining a phase included angle between a current vector and the voltage vector according to a given q-axis current and a given d-axis current, and detecting a corresponding q-axis dead-zone compensation voltage and a d-axis dead zone compensation voltage according to the phase included angle.
[0007] For sensorless control through HFI methods, it is preferable for the high frequency current to be considered when applying dead-time compensation. Especially for low speed with low load operations, the high frequency is dominant in deciding the sign of phase current. An exemplary method is to use the measured phase currents for dead-time compensation. However, because of feedback delay, pulse width modulation output delay, and noise in measured currents, the zero crossing may be inaccurate. If dead time is not compensated, significant oscillation in position estimation may be observed. Therefore, there is a need in the art to provide a method to compensate for dead time in a manner that prevents significant oscillation in position estimation.
[0008] SUMMARY OF THE INVENTION
[0009] It is an object of the invention to provide a method as well as a corresponding electronic computing device by which an oscillation in an estimated position is significantly reduced.
[0010] This object is solved by a method as well as a corresponding electronic computing device according to the independent claims. Advantageous embodiments are presented in the dependent claims.
[0011] One embodiment of the invention relates to a method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device, wherein a speed control and a position control of the interior permanent magnet synchronous machine are performed using sensorless control with a high frequency injection voltage by the electronic computing device.
[0012] In an embodiment, a phase current prediction is used for compensating the dead time, wherein the phase current prediction is predicted depending on fundamental three-phase currents and high frequency phase currents.
[0013] According to the presented embodiment, with the dead-time compensation for position and speed sensorless control with a high frequency injection, the oscillation in the estimated position is significantly reduced. Hence, the oscillation of achieved torque is greatly reduced, which improves sensorless controlled electrified powertrain performance regarding noise vibration harshness.
[0014] In an embodiment, the fundamental three-phase currents are determined depending on current commands by the electronic computing device.
[0015] In another embodiment, the fundamental three-phase currents are determined depending on an estimated rotor electrical position by the electronic computing device.
[0016] In a further embodiment, the high frequency phase currents are determined depending on an estimated rotor electrical position by the electronic computing device.
[0017] In another embodiment, the high frequency phase currents are determined by using a Park's and Clark's transformation performed by the electronic computing device.
[0018] Another aspect of the invention relates to the electronic computing device for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine, wherein the electronic computing device is configured to perform a method according to the preceding aspect. In particular, the method is performed by the electronic computing device.
[0019] Advantageous forms of configurations of the method are to be regarded as advantages forms of the electronic computing device. The electronic computing device therefore comprises means for performing the method.
[0020] Further advantages, features, and details of the invention derive from the following description of preferred embodiments as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respectively indicated combination but also in any other combination or taken alone without leaving the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The novel features and characteristics of the disclosure are set forth in the independent claims. The accompanying drawings, which are incorporated in and constitute part of this disclosure, illustrate exemplary embodiments and together with the description, serve to explain the disclosed principles. In the figures, the same reference signs are used throughout the figures to refer to identical features and components. Some embodiments of the system and/or methods in accordance with embodiments of the present subject matter are now described below, by way of example only, and with reference to the accompanying drawings.
[0022] The drawings show in: [0023] Fig. 1 a schematic block diagram according to an embodiment of the electronic computing device; and [0024] Fig. 2 four diagrams which represent the state of art and the method according to the invention.
In the figures same elements or elements having the same function are indicated by the same reference signs.
DETAILED DESCRIPTION
[0025] In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
[0026] While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.
[0027] The terms "comprises', "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion so that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus preceded by "comprises" or "comprise" does not or do not, without more constraints, preclude the existence of other elements or additional elements in the system or method.
[0028] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
[0029] Fig. 1 shows a schematic block diagram according to an embodiment of an electronic computing device 10. The electronic computing device 10 is configured for performing a method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine (IPMSM).
[0030] According to an embodiment, a method is presented for compensating for dead time of a voltage source inverter for an IPMSM by the electronic computing device 10. In an embodiment, speed control and/or position control of the IPMSM is performed using high frequency injection voltage u*HF. In another embodiment, phase current prediction ipred_abc is used for compensating for the dead time, wherein the phase current prediction ipred abc is predicted depending on fundamental three-phase currents i -abc* and high frequency phase currents i.HF_abc* [0031] According to an embodiment, the fundamental three-phase currents i *abc* are determined depending on current commands id*, id* by the electronic computing device 10. In another embodiment, the fundamental three-phase currents i *abc* are determined depending on an estimated rotor electrical position eds, of the IPMSM by the electronic device 10.
[0032] In an embodiment, the high frequency phase currents i *HE abc are determined depending on the estimated rotor electrical position Des, by the electronic computing device 10. In an embodiment the high frequency phase currents i.HF_abc are determined by using a Park's and Clark's transformation by the electronic device 10.
[0033] The Fig. 1 shows the block diagram of an embodiment of the phase current prediction method. Current commands id* and id" are transformed to fundamental three-phase currents iabc* with the estimated rotor electrical position Oust. The phase of injected high frequency voltage uHF"=V sin(wHFt) on direct axis (d axis) is subtracted by pi/2 (90 degree) to get the phase of the high frequency current sin(wHEt-pi/2) on d axis. With 0 on quadrature axis (q axis), and the estimated rotor electrical position *esi, the high frequency three-phase currents i *HF_abc may be obtained by Park's and Clark's transformation. In an embodiment, [(scale may be the gain to adjust the predicted current magnitude. In an embodiment, i.HF abc may be set to 0 if high frequency injection is inactive. The summation of the fundamental three-phase currents i -abc* and the high frequency three-phase currents iHF_abc is the final predicted phase currents ipred_abc, which may not have any delay and noise since it is calculated by current and voltage commands.
[0034] Fig. 2 shows four diagrams according to the state of the art and according to an embodiment of the invention. On the left side of Fig. 2, two diagrams representing the state of the art are shown. On the right side of Fig. 2, two diagrams representing an embodiment according to the invention are shown.
[0035] In a first diagram 12 the electric position over time t is shown. It is shown a resolver position 14 as well as an observer position 16. In a second diagram 18 according to the state of the art, a position error 20 is shown over time t. The first diagram 12 and the second diagram 18 represents the state of the art.
[0036] In a third diagram 22 the electrical position of the resolver position 14 and the electrical position of the observer position 16 are shown. In a fourth diagram 24 the position error over time t is shown. The third diagram 22 and the fourth diagram 24 represent an embodiment according to the invention.
[0037] According to a comparison of the first diagram 12 and the third diagram 22 and a comparison between the second diagram 18 and the fourth diagram 24, it is shown that by compensating for dead time effect using the predicted high frequency current, the oscillation of the angle estimation is significantly reduced.
[0038] According to an embodiment of the method for the dead-time compensation for position and speed sensorless control with a high frequency injection, the oscillation in estimated position is significantly reduced. Hence, the oscillation of achieved torque is significantly reduced, which improves sensorless controlled electrified powertrain performance regarding to noise vibration harshness.
Reference Signs electronic computing device 12 first diagram 14 resolver position 16 observer position 18 second diagram position error 22 third diagram 24 fourth diagram time id" current command iq current command iNF_abc high frequency phase currents Oest estimated rotor electrical position iabc* fundamental three phase currents ipred_abc phase current prediction U*HF high frequency injection voltage kscale gain
Claims (1)
- CLAIMS1. A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device (10), wherein a speed control and a position control of the interior permanent magnet synchronous machine are performed using sensorless control with a high frequency injection voltage (u'HE) by the electronic computing device, characterized in that a phase current prediction (i N*pred abc) is used for compensating the dead time, wherein the phase current prediction predicted depending on fundamental three-phase currents Oabc*) and high frequency phase currents (iHE 2. The method according to claim 1, characterized in that the fundamental three-phase currents 020 are determined depending on current commands (id*, iq*) by the electronic computing device (10).3. The method according to claim 1 or 2, characterized in that the fundamental three-phase currents (iabc") are determined depending on an estimated rotor electrical position 0%$ by the electronic computing device (10).4. The method according to any one of claims 1 to 3, characterized in that the high frequency phase currents II "HE abc) are determined depending on an estimated rotor electrical position (øest) by the electronic computing device (10).5. The method according to any one of claims 1 to 4, characterized in that the high frequency phase currents (i *I-IF abc) are determined by using a Park's and Clark's transformation by the electronic computing device (10).6. An electronic computing device (10) for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine, wherein the electronic computing device (10) is configured to perform a method of any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2016333.3A GB2600095A (en) | 2020-10-15 | 2020-10-15 | A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2016333.3A GB2600095A (en) | 2020-10-15 | 2020-10-15 | A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB202016333D0 GB202016333D0 (en) | 2020-12-02 |
| GB2600095A true GB2600095A (en) | 2022-04-27 |
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| Application Number | Title | Priority Date | Filing Date |
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| GB2016333.3A Withdrawn GB2600095A (en) | 2020-10-15 | 2020-10-15 | A method for compensating a dead time of a voltage source inverter for an interior permanent magnet synchronous machine by an electronic computing device |
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| Country | Link |
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| GB (1) | GB2600095A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114123751B (en) * | 2021-11-26 | 2023-10-10 | 珠海格力电器股份有限公司 | Dead zone compensation method, inverter control circuit, device and inverter |
| CN115585829B (en) * | 2022-09-07 | 2025-09-09 | 广东美的白色家电技术创新中心有限公司 | Method and device for acquiring running state of motor rotor, equipment and medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20170110999A1 (en) * | 2014-04-17 | 2017-04-20 | Aisin Aw Co., Ltd. | Rotary electric machine control device |
| CN110071669A (en) * | 2019-06-03 | 2019-07-30 | 北京机械设备研究所 | A kind of permanent magnet synchronous motor vector controlled " dead time effect " compensation method |
| CN110995072A (en) * | 2019-12-19 | 2020-04-10 | 华中科技大学 | Motor rotor position estimation method |
-
2020
- 2020-10-15 GB GB2016333.3A patent/GB2600095A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20170110999A1 (en) * | 2014-04-17 | 2017-04-20 | Aisin Aw Co., Ltd. | Rotary electric machine control device |
| CN110071669A (en) * | 2019-06-03 | 2019-07-30 | 北京机械设备研究所 | A kind of permanent magnet synchronous motor vector controlled " dead time effect " compensation method |
| CN110995072A (en) * | 2019-12-19 | 2020-04-10 | 华中科技大学 | Motor rotor position estimation method |
Also Published As
| Publication number | Publication date |
|---|---|
| GB202016333D0 (en) | 2020-12-02 |
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| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |