Method for determining optimal distance between pantographs in double-pantograph or multi-pantograph operation of high-speed railway

Abstract

The invention discloses a method for determining the optimal distance between pantographs under the double-pantograph or multi-pantograph operation of a high-speed railway, and the method specifically comprises the steps: constructing a pantograph-catenary coupling model, carrying out the dynamic simulation, extracting the midspan lifting displacement of the middle span of a catenary under the excitation of a single pantograph, dividing a contact line displacement response region, and determining the optimal distance between the pantographs. Performing frequency domain analysis on the lifting response of the overhead line system in the third area, and calculating the main vibration wavelength of the overhead line system when the pantograph is excited at the speed v; introducing a scale factor of the ratio of the overhead line system span to the overhead line system vibration wavelength; comprehensively analyzing the propagation law of vibration waves, and proposing a calculation formula of the optimal distance between two bows or multiple bows; and simulating and checking the optimization result. According to the invention, the accuracy of a calculation result is obviously improved; the method is suitable for solving the favorable spacing of the high-speed train multi-pantograph-catenary system, and an important theoretical basis is provided for the design of the multi-pantograph-catenary system.

Description

Technical Field

[0001] The present invention belongs to the field of high-speed railway pantograph-catenary systems, and in particular relates to a method for determining an optimal pantograph spacing when a high-speed railway has double or multiple pantographs. Background Art

[0002] The pantograph contact network system is located at the end of the traction power supply system and provides the electric energy required by electric locomotives or trains. With the acceleration of China's economic development and urbanization, the passenger demand between different cities is increasing, especially during holidays. The huge passenger flow has brought great challenges to the carrying capacity of high-speed trains. In order to improve the passenger carrying capacity and running speed of the train, high-speed trains usually adopt a reconnection method and equip two or more pantographs to improve the carrying capacity of the train. However, the double-pantograph and multi-pantograph current collection system faces the challenge of the current collection quality of high-speed trains. The mechanical wave caused by the front pantograph propagates along the contact network to the rear pantograph, resulting in a sharp deterioration of the current collection quality of the rear pantograph. How to improve the current collection quality of the rear pantograph is an important problem that needs to be solved for the safe operation of the multi-pantograph network system. Zhang Weihua et al. gave the optimal spacing of the double-pantograph operation based on the propagation law of the contact network wave, but the correction coefficient in the formula is a fixed value. When the speed and contact network type change, the formula is no longer applicable. Xu Zhao et al. analyzed the contact network lifting speed response under the action of a single moving force and discussed the optimal spacing of the double-pantograph operation, but the speed response is relatively complex, and the filtering process is prone to data distortion, resulting in large errors in the calculation results. The above two methods are not suitable for high-speed bow-net systems, and existing research mainly focuses on the problem of double-bow spacing, and no method for determining the spacing between each bow in the operation of three or more bows is given. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for determining the optimal pantograph spacing under double-pan or multi-pan operation of a high-speed railway.

[0004] The present invention considers the double-bow and multi-bow working conditions of high-speed operation, analyzes the frequency domain characteristics of the catenary lifting displacement response, explores the propagation law of vibration waves, introduces proportional factors, and proposes a calculation method for the optimal spacing of double-bow and multi-bow, which significantly improves the current collection quality of the rear bow. A method for determining the optimal spacing of pantographs under the operation of double-bow or multi-bow high-speed railways of the present invention comprises the following steps:

[0005] Step 1: The pantograph adopts a three-mass block model, establishes a contact network model based on nonlinear cable-rod units, and uses a penalty function to construct a pantograph-catenary coupling model. The model accuracy is verified by comparing it with the EN50318-2018 standard.

[0006] Step 2: Set the high-speed train running speed v, perform pantograph-catenary coupling dynamics simulation, and extract the mid-span lift displacement of the middle span of the catenary under single pantograph excitation.

[0007] Step 3: The contact line displacement response is divided into three regions: the first is the region before the pantograph reaches the mid-span point; the second is the region from the pantograph reaching the mid-span point to the point where the displacement is zero after the first peak, and the length is defined as L t ; The third one is the area from the zero value point to the end point of the simulation time.

[0008] Step 4: Conduct frequency domain analysis of the catenary uplift response in the third area and use Matlab tools to calculate the main vibration wavelength λ of the catenary when the pantograph is excited at speed v.

[0009] Step 5: Define the contact network span L 跨 The ratio of the contact network vibration wavelength λ is the proportional factor α, and the α corresponding to the speed v is calculated v .

[0010] Step 6: Comprehensively analyze the propagation law of vibration waves and propose the calculation formula for the optimal spacing between the two arches:

[0011]

[0012] Where, L g is the optimal spacing between pantographs, L 跨 is the contact network span, and k is a natural number.

[0013] Step 7: When the high-speed train is running with three pantographs, the pantographs are defined as the front pantograph, the middle pantograph and the rear pantograph according to the running direction. The first two pantographs are taken as a whole, and the optimal spacing L between the front pantograph and the middle pantograph is g Calculated from step 6.

[0014] Different from the double-bow spacing solution process, the end point of the first area is the mid-span position where the middle bow reaches the middle span of the contact network. This position is also the starting point of the second area. The division method of other areas is the same as step 3.

[0015] This method is still applicable when high-speed trains have more than three bows in operation.

[0016] Step 8: Extract the mid-span uplift response of the catenary under the excitation of the double-bow velocity v and calculate α v ′ and L t ′.

[0017] Step 9: Compare the catenary lifting displacement under the excitation of different numbers of pantographs, and give the calculation formula for the optimal spacing of the three pantographs:

[0018]

[0019] Where, L g ′ is the optimal distance between the middle arch and the rear arch, L 跨 is the contact network span, and k is a natural number.

[0020] Step 10: Perform double-pantograph and triple-pantograph network coupling dynamics simulations respectively, and use Matlab tools to extract the standard deviation s of the contact force at different pantograph spacings. d , the calculation results obtained by formula (1) and formula (2) are compared with the simulation results to verify the accuracy of the optimal spacing of double and triple arches.

[0021] The beneficial technical effects of the present invention compared with the prior art are:

[0022] Under the operating conditions of double-panes and multiple-panes of high-speed trains, the present invention analyzes the dynamic lifting displacement response of the contact network, provides a calculation method for the optimal spacing of double-panes and multiple-panes, improves the current-collecting quality of the rear pantograph, and enhances the dynamic performance of the double-pane and multiple-pano-network system. Compared with the previous calculation method for the optimal spacing of pantographs, this method uses the actual lifting displacement response of the contact network, which significantly improves the accuracy of the calculation results; it is suitable for solving the favorable spacing of the high-speed train multiple-pano-network system (three or more pantographs), and provides an important theoretical basis for the design of the multiple-pano-network system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the multi-pantograph-network coupling system of a high-speed train.

[0024] Figure 2 This is a schematic diagram of the pantograph-catenary coupling model established using MATLAB (where a is a simplified schematic diagram of the pantograph, b is a simplified schematic diagram of the catenary, and c is a simplified schematic diagram of the pantograph-catenary coupling).

[0025] Figure 3 It is the mid-span uplift response of the middle span of the overhead contact network under the excitation of a single pantograph at a speed of 350km / h.

[0026] Figure 4 It is the mid-span uplift response of the middle span of the overhead contact network under the excitation of double pantographs at a speed of 350km / h.

[0027] Figure 5 This is a comparison chart between the calculation results and simulation results of the optimal spacing between the two arches.

[0028] Figure 6 This is a comparison chart between the calculation results and simulation results of the optimal spacing between the three arches. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0030] In this embodiment, the DSA380 pantograph and the overhead contact network data of the Beijing-Tianjin Line are used, where the double-pan and triple-panel operating speed v = 350km / h, and the overhead contact network span is L 跨 =50m.

[0031] The present invention provides a method for determining the optimal pantograph spacing under double-pano or multi-pano operation of a high-speed railway, which is applicable to a multi-pano-network coupling system of a high-speed train, such as Figure 1 As shown, the method of the present invention specifically comprises the following steps:

[0032] Step 1: The pantograph adopts a three-mass block model, establishes a contact network model based on nonlinear cable-rod units, and uses a penalty function to construct a pantograph-network coupling model, such as Figure 2 As shown, the accuracy of the model is verified by comparing it with the EN50318-2018 standard.

[0033] Step 2: Set the high-speed train running speed v, perform pantograph-catenary coupling dynamics simulation, and extract the mid-span lift displacement of the middle span of the catenary under single pantograph excitation.

[0034] Step 3: The contact line displacement response is divided into three regions, such as Figure 3 As shown: the first is the area before the pantograph reaches the mid-span point; the second is the area from the pantograph reaching the mid-span point to the point where the displacement is zero after the first crest, and the length is defined as L t ; The third one is the area from the zero value point to the end point of the simulation time.

[0035] Step 4: Conduct frequency domain analysis of the catenary uplift response in the third area and use Matlab tools to calculate the main vibration wavelength λ of the catenary when the pantograph is excited at speed v.

[0036] Step 5: Define the contact network span L 跨 The ratio of the contact network vibration wavelength λ is the proportional factor α, and the α corresponding to the speed v is calculated v .

[0037] Step 6: Comprehensively analyze the propagation law of vibration waves and propose the calculation formula for the optimal spacing between the two arches:

[0038]

[0039] Where, L g is the optimal spacing between pantographs, L 跨 is the contact network span, and k is a natural number.

[0040] Step 7: Extract the lifting displacement of the mid-span point of the contact network under the excitation of the double pantograph at speed v, and divide it into three regions, such as Figure 4 As shown. Same as step 4 and step 5, calculate L t ′ and α v ′;

[0041] Step 8: Compare the catenary lifting displacement under the excitation of different numbers of pantographs, and give the calculation formula for the optimal spacing of the three pantographs:

[0042]

[0043] Where, L g ′ is the optimal distance between the middle arch and the rear arch, L 跨 is the contact network span, and k is a natural number.

[0044] Step 9: Check the optimization results: Conduct double-pantograph and triple-pantograph network coupling dynamics simulations respectively, and use Matlab tools to extract the standard deviation s of the contact force under different pantograph spacings. d , the calculation results obtained by formula (1) and formula (2) are compared with the simulation results to verify the correctness of the calculation results.

[0045] After the calculations in the above steps, we can obtain α under single bow excitation. v＝350 =0.688, α under double bow excitation v＝350 ′=0.644; L under single bow excitation t =109.28m, L under double bow excitation t ′=92.17m. Substitute the obtained parameters into formula (1) and formula (2) respectively to calculate the optimal spacing of double and triple pantographs. Use step 9 to obtain the standard deviation of the contact force of the double and triple pantograph network systems with different pantograph spacings. The comparison between the calculation results of the optimal spacing and the simulation results is shown in Figure 9. Figure 5 and Figure 6 As shown, it can be seen that the optimal spacing calculated by the method proposed in the present invention is highly consistent with the simulation results, which verifies that the method can be used to solve the optimal spacing of double-bow and multi-bow systems, improve the current-collecting quality of the rear bow, and enhance the dynamic performance of double-bow and multi-bow networks.

Claims

1. A method for determining the optimal pantograph spacing in high-speed railway double-pan or multi-pan operation, characterized in that: The following steps are involved: Step 1: The pantograph adopts a three-mass block model, establishes a contact network model based on nonlinear cable-rod units, and uses a penalty function to construct a pantograph-catenary coupling model. The model accuracy is verified by comparing it with the EN50318-2018 standard. Step 2: Set the high-speed train running speed v, perform pantograph-catenary coupling dynamics simulation, and extract the mid-span lift displacement of the middle span of the contact network under single pantograph excitation; Step 3: The contact line displacement response is divided into three regions: the first is the region before the pantograph reaches the mid-span point; the second is the region from the pantograph reaching the mid-span point to the point where the displacement is zero after the first peak, and the length is defined as L t ; The third one is the area from the zero value point to the end point of the simulation time; Step 4: Conduct frequency domain analysis of the catenary lifting response in the third area, and use Matlab tools to calculate the main vibration wavelength λ of the catenary when the pantograph is excited at a speed v; Step 5: Define the contact network span L 跨 The ratio of the contact network vibration wavelength λ is the proportional factor α, and the α corresponding to the speed v is calculated v ; Step 6: Comprehensively analyze the propagation law of vibration waves and propose the calculation formula for the optimal spacing between the two arches: Where, L g is the optimal spacing between pantographs, L 跨 is the overhead contact network span, k is a natural number; Step 7: When the high-speed train is running with three pantographs, the pantographs are defined as the front pantograph, the middle pantograph and the rear pantograph according to the running direction. The first two pantographs are taken as a whole, and the optimal spacing L between the front pantograph and the middle pantograph is g Calculated from step 6; Different from the double-bow spacing solution process, the end point of the first area is the mid-span position where the middle bow reaches the middle span of the contact network. This position is also the starting point of the second area. The division method of other areas is the same as step 3. Step 8: Extract the mid-span uplift response of the catenary under the excitation of the double-bow velocity v and calculate α v ′ and L t ′; Step 9: Compare the catenary lifting displacement under the excitation of different numbers of pantographs, and give the calculation formula for the optimal spacing of the three pantographs: Where, L g ′ is the optimal distance between the middle arch and the rear arch, L 跨 is the overhead contact network span, k is a natural number; Step 10: Perform double-pantograph and triple-pantograph network coupling dynamics simulations respectively, and use Matlab tools to extract the standard deviation s of the contact force at different pantograph spacings. d , the calculation results obtained by formula (1) and formula (2) are compared with the simulation results to verify the accuracy of the optimal spacing of double and triple arches.

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