Method, device and frequency converter for controlling motor output torque
By acquiring historical stopping torque and combining it with a PID algorithm to adjust the motor output torque, the problem of unstable train startup was solved, improving passenger comfort.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SIEMENS (CHINA) CO LTD
- Filing Date
- 2022-05-24
- Publication Date
- 2026-07-10
AI Technical Summary
In existing technologies, due to uncertainties in road conditions and loads, the use of fixed torque control during train startup leads to unstable startup, affecting passenger comfort.
By acquiring historical stopping torque and controlling the motor output torque during train startup, combined with a PID algorithm to transition to normal operating torque, the torque is adjusted according to road conditions and load information.
It improves the smoothness of the train's start-up phase and enhances passenger comfort.
Smart Images
Figure CN115051614B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of train operation control, and in particular to a method, device and frequency converter for controlling the output torque of a motor. Background Technology
[0002] Many types of trains, such as monorail sightseeing trains, use frequency converters to control the output torque of their motors during startup and operation to achieve the purpose of controlling the train's operation.
[0003] Currently, most trains use frequency converters to provide a fixed starting torque to the motor during startup, and the train starts using this starting torque.
[0004] However, since the road conditions and loads vary when a train starts, if the torque is too high, overshoot will occur; if the torque is too low, slippage will occur. Therefore, starting with a fixed starting torque will result in the train not starting smoothly, which will affect the comfort of passengers when the train starts. Summary of the Invention
[0005] In view of this, the present invention proposes a method, device and frequency converter for controlling the output torque of a motor, in order to improve passenger comfort when the train starts.
[0006] According to the first aspect, a method for controlling the output torque of a motor is provided, which includes:
[0007] When a start command is detected, the historical stopping torque is obtained; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation.
[0008] During the train start-up phase, the output torque of the motor is controlled based on the historical stopping torque.
[0009] In one embodiment of the first aspect, the historical parking torque includes:
[0010] The output torque of the motor when a stop command was detected during the train's last historical operation;
[0011] or,
[0012] The average value of the motor's output torque when a stop command is detected during any N historical runs of the train.
[0013] In one embodiment of the first aspect, after controlling the output torque of the motor based on the historical parking torque, the method further includes:
[0014] Check whether the train has entered the normal operation phase;
[0015] Once it is determined that the train has entered the normal operating phase, the output torque of the motor is controlled to be the torque set by the preset torque control strategy.
[0016] In one embodiment of the first aspect, detecting whether the train has entered the normal operation phase includes:
[0017] Determine whether the running time of the train entering the start-up phase has reached a preset time; if the running time of the train entering the start-up phase has reached the preset time, then determine that the train has entered the normal operation phase.
[0018] or,
[0019] Obtain the train's operating speed; determine whether the train has entered the normal operating phase based on the operating speed.
[0020] In one embodiment of the first aspect, controlling the output torque of the motor to be the torque set by a preset torque control strategy includes:
[0021] Obtain the current load information and current road condition information of the train;
[0022] The motor output torque corresponding to the current load information and current road condition information is queried from the preset torque control strategy;
[0023] The output torque of the motor is controlled to be the motor output torque corresponding to the current load information and the current road condition information.
[0024] In one embodiment of the first aspect, after controlling the output torque of the motor based on the historical parking torque, the method further includes:
[0025] Calculate the torque during the normal operation phase of the train;
[0026] The output torque of the motor is controlled by a PID algorithm to transition from the historical stopping torque to the torque during the normal operation of the train.
[0027] In one embodiment of the first aspect, obtaining the historical parking torque includes:
[0028] Obtain the historical output torque of the motor latched by the latch during the train's historical operation.
[0029] According to the second aspect, a control device for the output torque of a motor is provided, comprising:
[0030] The acquisition unit is configured to acquire historical stopping torque when a start command is detected; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation.
[0031] The first control unit is configured to control the output torque of the motor based on the historical stopping torque during the train start-up phase.
[0032] In one embodiment of the second aspect, the historical parking torque includes:
[0033] The output torque of the motor when a stop command was detected during the train's last historical operation;
[0034] or,
[0035] The average value of the motor's output torque when a stop command is detected during any N historical runs of the train.
[0036] In one embodiment of the second aspect, the apparatus further includes:
[0037] The detection unit is configured to detect whether the train has entered the normal operation phase;
[0038] The second control unit is configured to control the output torque of the motor to the torque set by a preset torque control strategy after it is determined that the train has entered the normal operation phase.
[0039] In one embodiment of the second aspect, the detection unit is configured as follows:
[0040] Determine whether the running time of the train entering the start-up phase has reached a preset time; if the running time of the train entering the start-up phase has reached the preset time, then determine that the train has entered the normal operation phase.
[0041] or,
[0042] Obtain the train's operating speed; determine whether the train has entered the normal operating phase based on the operating speed.
[0043] In one embodiment of the second aspect, the second control unit is configured as follows:
[0044] Obtain the current load information and current road condition information of the train;
[0045] The motor output torque corresponding to the current load information and current road condition information is queried from the preset torque control strategy;
[0046] The output torque of the motor is controlled to be the motor output torque corresponding to the current load information and the current road condition information.
[0047] In one embodiment of the second aspect, the apparatus further includes:
[0048] The calculation unit is configured to calculate the torque during the normal operation phase of the train;
[0049] The third control unit is configured to control the output torque of the motor to transition from the historical stopping torque to the torque during the normal operation of the train using a PID algorithm.
[0050] In one embodiment of the second aspect, the acquisition unit is configured as follows:
[0051] Obtain the historical output torque of the motor latched by the latch during the train's historical operation.
[0052] According to a third aspect, a computer-readable storage medium is provided, on which a computer program is stored, which, when executed in a computer, performs the method described in the first aspect.
[0053] Fourthly, a frequency converter is provided, which includes a memory and a processor, wherein the memory stores executable code, and the processor executes the executable code to implement the method described in the first aspect.
[0054] As can be seen from the above solutions, the motor output torque control method and device provided in the embodiments of the present invention obtain historical parking torque and control the motor output torque according to the historical parking torque during the train start-up phase. Since the historical parking torque reflects the change pattern of the motor output torque when a parking command is detected during the train's historical operation, and when the torque during the parking phase and the motor output torque during the start-up phase are related, the motor output torque will be more consistent, thus improving the smoothness of the train start-up phase and thereby improving the passenger's riding comfort during the train start-up phase. Attached Figure Description
[0055] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which will make the above and other features and advantages of the present invention more apparent to those skilled in the art. In the drawings:
[0056] Figure 1 A flowchart of a method for controlling the output torque of a motor provided in an embodiment of the present invention.
[0057] Figure 2 A flowchart of a method for controlling the output torque of a motor, provided in another embodiment of the present invention.
[0058] Figure 3 This is a flowchart illustrating how the output torque of the motor is controlled to be the torque set by a preset torque control strategy in one embodiment of the present invention.
[0059] Figure 4 A flowchart of a method for controlling the output torque of a motor, provided in another embodiment of the present invention.
[0060] Figure 5 This is a block diagram of a motor output torque control device provided in one embodiment of the present invention.
[0061] Figure 6 A block diagram of a motor output torque control device provided for another embodiment of the present invention.
[0062] Figure 7 A block diagram of a motor output torque control device provided for another embodiment of the present invention.
[0063] List of reference numerals in the attached diagram:
[0064] 101: When a start command is detected, obtain the historical stopping torque; the historical stopping torque is the motor's output torque when a stopping command is detected during the train's historical operation.
[0065] 103: During the train startup phase, the output torque of the motor is controlled based on the historical stopping torque.
[0066] 105: Check whether the train has entered the normal operation phase.
[0067] 107: Once the train has entered the normal operating phase, the output torque of the control motor is set to the torque specified by the preset torque control strategy.
[0068] 1071: Obtain the train's current load information and current road condition information.
[0069] 1073: Query the motor output torque corresponding to the current load information and current road condition information from the preset torque control strategy.
[0070] 1075: The output torque of the control motor is the motor output torque corresponding to the current load information and current road condition information.
[0071] 109: Calculate the torque during normal train operation.
[0072] 111: The output torque of the control motor is transitioned from the historical stopping torque to the torque during normal train operation using a PID algorithm.
[0073] 501: Acquisition Unit
[0074] 503: First Control Unit
[0075] 505: Detection Unit
[0076] 507: Second Control Unit
[0077] 509: Computing Unit
[0078] 511: Third Control Unit Detailed Implementation
[0079] To make the objectives, technical solutions, and advantages of the present invention clearer, the following embodiments are provided to further illustrate the present invention in detail.
[0080] Many types of trains use frequency converters to control the output torque of their motors during startup and operation. These trains include monorail sightseeing trains and double-rail sightseeing trains. These trains typically have at least one carriage, and each carriage has one, two, or four motors that output torque, which can be controlled by one, two, or four frequency converters.
[0081] During the train's start-up phase, especially for monorail and double-rail sightseeing trains, the output torque of the motor controlled by the frequency converter will vary due to uncertainties in road conditions (uphill, flat, downhill, etc.) and passenger load (full carriage, 70% full carriage, 50% full carriage). If the frequency converter controls the motor by outputting a fixed torque, it is clearly not scientific and will affect the train's starting stability, thus impacting passenger comfort during the start-up phase. Therefore, it is necessary to provide a motor output torque control method suitable for the train's start-up phase, and the embodiments of this invention aim to achieve this objective.
[0082] This invention proposes a method for controlling the output torque of a motor based on the free function blocks of a frequency converter. The execution subject of this method can be any frequency converter on a train. The concept of the embodiments described in this specification will be explained in detail below.
[0083] Figure 1 This is a flowchart illustrating a method for controlling the output torque of a motor according to an embodiment of the present invention. The executing entity of this method includes, but is not limited to, any frequency converter on a monorail sightseeing train or a double-rail sightseeing train. Figure 1 As shown, the method includes the following steps:
[0084] Step 101: When a start command is detected, obtain the historical stopping torque; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation.
[0085] The start command can be the action of pressing the start button; that is, when the start button is detected being pressed, a start command is determined to have been detected. The stop command can be the action of pressing either the normal stop button or the emergency stop button; that is, when either the normal stop button or the emergency stop button is detected being pressed, a stop command is determined to have been detected.
[0086] Step 103: During the train start-up phase, control the output torque of the motor based on the historical stopping torque.
[0087] The motor in question is a motor controlled by a frequency converter. For example, if the frequency converter is the one that controls the left front wheel of the sixth car in a monorail sightseeing train, then the motor is the one that controls the output torque of the left front wheel of the sixth car.
[0088] Since historical stopping torque reflects the change pattern of motor output torque when a stopping command is detected during the train's historical operation, and when the torque during the stopping phase is related to the motor output torque during the starting phase, for example, when the output torque of the motor during the previous stopping phase is applied to the next starting phase, the motor output torque will be more consistent, with an effect similar to not stopping, thus improving the smoothness of the train's starting phase. Therefore, the embodiments of the present invention control the motor output torque according to historical stopping torque during the train starting phase, which can improve the running smoothness of the train during the starting phase, thereby improving the passenger's riding comfort during the train starting phase.
[0089] Specifically, when controlling the motor's output torque based on historical stopping torque, the motor's output torque can be controlled to the historical stopping torque during the train startup phase.
[0090] In one specific embodiment of this specification, the frequency converter is typically equipped with a latch. When a stop command is detected, the latch latches the output torque of the motor and stores the latched torque in a memory. Therefore, when obtaining the historical stop torque in step 101, the historical output torque of the motor latched by the latch during the historical operation of the train can be obtained.
[0091] Furthermore, since the output torque of the motor during the train start-up phase is the same as the output torque of the motor when the train detected a stop command during its previous historical operation, the output torque of the motor during the previous stop and this start can be made continuous, thus ensuring a smooth start for the train. Therefore, in this embodiment of the invention, the historical stop torque is preferably the output torque of the motor when the train detected a stop command during its previous historical operation.
[0092] In addition, when the train's load and road conditions are similar, the output torque of the motor when a stop command is detected during historical operation will also be similar. In this case, the historical stop torque in this embodiment of the invention can be the average value of the output torque of the motor when a stop command is detected during any N historical operations of the train, so that the output torque of the motor in this starting phase is determined by combining multiple historical stop processes, and the determined historical stop torque is more reasonable.
[0093] Of course, the historical stopping torque can also be the output torque of the motor when a stopping command is detected at any time during N historical operations. The specific torque can be selected as needed, and this embodiment of the invention does not impose any specific limitations on it.
[0094] In another embodiment of this specification, after the train transitions from the starting phase to the normal operating phase, the control strategy for its motor output torque varies depending on road conditions and load. To ensure that the motor can output appropriate torque after the train transitions from the starting phase to the normal operating phase, such as... Figure 2 As shown, after controlling the motor's output torque based on historical stopping torque during the train startup phase, this embodiment of the invention may further include the following steps:
[0095] Step 105: Check whether the train has entered the normal operation phase.
[0096] Step 107: Once it is determined that the train has entered the normal operation phase, control the output torque of the motor to be the torque set by the preset torque control strategy.
[0097] Step 105, when detecting whether the train has entered the normal operation phase, includes, but is not limited to, the following two methods:
[0098] The first method is to determine whether the train's running time in the start-up phase has reached the preset duration; if the train's running time in the start-up phase has reached the preset duration, then the train is determined to have entered the normal operation phase.
[0099] For example, the preset duration can be determined based on the duration from detecting the start command to entering the normal operation phase during historical operation processes. For instance, the preset duration can be the average of the durations from detecting the start command to entering the normal operation phase during N historical operation processes.
[0100] The second method is to obtain the train's operating speed and determine whether the train has entered the normal operating phase based on the operating speed.
[0101] During train operation, the train's speed may increase continuously during the initial startup phase. However, once the train enters the normal operating phase, different gears correspond to different speeds, and the speeds at each gear are often relatively constant. Therefore, this method acquires the train's speed in real time and determines whether the train has entered the normal operating phase based on that speed. Specifically, when the speed is constant, the train is considered to have entered the normal operating phase. When the speed still has some acceleration, the train is considered not to have entered the normal operating phase.
[0102] Furthermore, such as Figure 3 As shown, step 107, when controlling the output torque of the motor to be the torque set by the preset torque control strategy, is achieved through, but is not limited to, the following steps:
[0103] Step 1071: Obtain the train's current load information and current road condition information.
[0104] Specifically, the current load information of the train can be obtained from the weighing sensors installed on the train. The current road condition information can be determined based on the current operating speed obtained from the speed sensors installed on the train. For example, if the train is going uphill, its current operating speed will usually be lower than the operating speed of the gear it is currently in; that is, if the current operating speed is lower than the operating speed of the gear the train is currently in, it can be determined that the train is going uphill.
[0105] Step 1073: Query the motor output torque corresponding to the current load information and current road condition information from the preset torque control strategy.
[0106] The preset torque control strategy stores the motor output torque corresponding to load information and road condition information. By comparing the current load information and current road condition information with the load information and road condition information stored in the preset torque control strategy, the motor output torque corresponding to the current load information and current road condition information can be obtained.
[0107] Step 1075: Control the motor output torque to be the motor output torque corresponding to the current load information and current road condition information.
[0108] This invention controls the motor's output torque to correspond to the current load information and current road condition information. This ensures that the torque output by the motor during normal train operation is calculated based on the actual load and road conditions, thus ensuring normal train operation while providing reasonable torque based on load and road conditions, resulting in higher passenger comfort.
[0109] In another embodiment of this specification, since there is often a difference between the torque of the motor during the starting phase and the torque during normal train operation, directly converting the torque from the starting phase to the normal train operation torque would cause sudden changes in the train's torque, such as sudden acceleration or sudden braking, which would cause discomfort to passengers. To avoid this situation, such as... Figure 4 As shown, after controlling the motor's output torque based on historical parking torque, this embodiment of the invention may further include the following steps:
[0110] Step 109: Calculate the torque during normal train operation.
[0111] Specifically, this step is implemented through steps 1071 to 1075, including but not limited to.
[0112] Step 111: The output torque of the motor is controlled by using a PID algorithm to transition from the historical stopping torque to the torque during normal train operation.
[0113] By employing a PID algorithm to transition from historical stopping torque to torque during normal train operation, a smooth transition of motor output torque from the start-up phase to the normal operation phase is achieved, further enhancing passenger comfort.
[0114] This specification also provides an embodiment of a control device for the motor output torque; see [link to embodiment]. Figure 5 ,include:
[0115] The acquisition unit 501 is configured to acquire the historical stopping torque when a start command is detected; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation.
[0116] The first control unit 503 is configured to control the output torque of the motor based on the historical stopping torque during the train start-up phase.
[0117] In one embodiment of the motor output torque control device in this specification, the historical stopping torque includes:
[0118] The output torque of the motor when a stop command was detected during the train's last historical operation;
[0119] or,
[0120] The average value of the motor's output torque when a stop command is detected during any N historical runs of the train.
[0121] In one embodiment of the motor output torque control device in this specification, such as Figure 6 As shown, the device also includes:
[0122] Detection unit 505 is configured to detect whether the train has entered the normal operation phase;
[0123] The second control unit 507 is configured to control the output torque of the motor to the torque set by the preset torque control strategy after it is determined that the train has entered the normal operation phase.
[0124] In one embodiment of the motor output torque control device in this specification, the detection unit 505 is configured as follows:
[0125] Determine whether the train's running time in the start-up phase has reached the preset duration; if the train's running time in the start-up phase has reached the preset duration, then determine that the train has entered the normal operation phase.
[0126] or,
[0127] Obtain the train's operating speed; determine whether the train has entered the normal operating phase based on the operating speed.
[0128] In one embodiment of the motor output torque control device in this specification, the second control unit 507 is configured as follows:
[0129] Obtain the train's current load information and current road condition information;
[0130] Query the motor output torque corresponding to the current load information and current road condition information from the preset torque control strategy;
[0131] The output torque of the control motor is the motor output torque corresponding to the current load information and current road condition information.
[0132] In one embodiment of the motor output torque control device in this specification, such as Figure 7 As shown, the device also includes:
[0133] The calculation unit 509 is configured to calculate the torque during the normal operation phase of the train;
[0134] The third control unit 511 is configured to control the output torque of the motor by using a PID algorithm to transition from the historical stopping torque to the torque during normal train operation.
[0135] In one embodiment of the motor output torque control device in this specification, the acquisition unit 501 is configured as follows:
[0136] Obtain the historical output torque of the motor latched by the latch during the train's historical operation.
[0137] This specification provides, in one embodiment, a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the methods of any embodiment in the specification.
[0138] This specification provides an embodiment of a frequency converter, including a memory and a processor. The memory stores executable code, and when the processor executes the executable code, it implements the method of any embodiment in this specification.
[0139] It is understood that the structures illustrated in the embodiments of the present invention do not constitute a specific limitation on the device for calculating device lifespan. In other embodiments of the specification, the device for calculating device lifespan may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.
[0140] The information interaction and execution process between the modules in the above-mentioned device and system are based on the same concept as the method embodiments in this specification, and the specific details can be found in the descriptions in the method embodiments in this specification, so they will not be repeated here.
[0141] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the apparatus embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.
[0142] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in this invention can be implemented using hardware, software, widgets, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium.
[0143] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solution of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for controlling the output torque of a motor, characterized in that, include: When a start command is detected, the historical stopping torque is obtained; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation. During the train startup phase, the output torque of the motor is controlled based on the historical stopping torque. After controlling the motor's output torque based on the historical parking torque, the method further includes: Detecting whether the train has entered the normal operation phase includes: determining whether the running time of the train entering the start-up phase has reached a preset time; if the running time of the train entering the start-up phase has reached the preset time, then determining that the train has entered the normal operation phase; or, acquiring the running speed of the train; and determining whether the train has entered the normal operation phase based on the running speed. Once it is determined that the train has entered the normal operating phase, the output torque of the motor is controlled to be the torque set by the preset torque control strategy.
2. The method according to claim 1, characterized in that, The historical stopping torque includes: The output torque of the motor when a stop command was detected during the train's last historical operation; or, The average value of the motor's output torque when a stop command is detected during any N historical runs of the train.
3. The method according to claim 1, characterized in that, The control of the motor's output torque to be the torque set by a preset torque control strategy includes: Obtain the current load information and current road condition information of the train; The motor output torque corresponding to the current load information and current road condition information is queried from the preset torque control strategy; The output torque of the motor is controlled to be the motor output torque corresponding to the current load information and the current road condition information.
4. The method according to claim 1, characterized in that, After controlling the motor's output torque based on the historical parking torque, the method further includes: Calculate the torque during the normal operation phase of the train; The output torque of the motor is controlled by a PID algorithm to transition from the historical stopping torque to the torque during the normal operation of the train.
5. The method according to claim 1, characterized in that, The acquisition of historical parking torque includes: Obtain the historical output torque of the motor latched by the latch during the train's historical operation.
6. A control device for the output torque of a motor, characterized in that, include: The acquisition unit is configured to acquire historical stopping torque when a start command is detected; the historical stopping torque is the output torque of the motor when a stopping command is detected during the train's historical operation. The control unit is configured to, during the train start-up phase, control the output torque of the motor based on the historical stopping torque, and after controlling the output torque of the motor based on the historical stopping torque, detect whether the train has entered the normal operation phase, and when it is determined that the train has entered the normal operation phase, control the output torque of the motor to the torque set by a preset torque control strategy. The step of detecting whether the train has entered the normal operation phase includes: determining whether the running time of the train entering the start-up phase has reached a preset time; if the running time of the train entering the start-up phase has reached the preset time, then determining that the train has entered the normal operation phase; or, acquiring the running speed of the train; and determining whether the train has entered the normal operation phase based on the running speed.
7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed in a computer, performs the method of any one of claims 1-5.
8. A frequency converter, characterized in that, The device includes a memory and a processor, wherein the memory stores executable code, and the processor executes the executable code to implement the method of any one of claims 1-5.