An electrified railway same-phase energy storage power supply system, control method and measurement and control unit

Abstract

The present invention provides an electrified railway co-phase energy storage power supply system, a control method and a measurement and control unit, and relates to the technical field of electrified railway traction power supply. The voltage transformer arranged on the co-phase power supply bus and the current transformer measuring end arranged on the feeder are respectively connected to the detection signal input end of the measurement and control unit, one end of the traction side winding of the traction main transformer is grounded, and the other end is connected to the co-phase power supply bus, the n groups of conversion side windings of the first traction matching transformer are connected to the n groups of parallel side ports of the co-phase converters in a one-to-one correspondence, and the m groups of conversion side windings of the second traction matching transformer are connected to the m groups of AC side ports of the energy storage converters in a one-to-one correspondence; the voltage transformer and the current transformer measuring end are respectively connected to the detection signal input end of the measurement and control unit, and the control signal output end of the measurement and control unit is connected to the control end of the co-phase converter and the control end of the energy storage converter.

Description

Technical Field

[0001] The present invention relates to the technical field of electrified railway traction power supply, and in particular to an electrified railway co-phase energy storage power supply system, a control method and a control unit. Background Art

[0002] When electric locomotives in electrified railways slow down or go downhill at stops, a large amount of regenerative braking energy is generated. Under the traditional traction power supply mode, this part of energy is absorbed by the trains at a low rate, and most of it is returned to the power grid. Since it is unplanned power generation, it will have an adverse effect on the power grid. The power system often punishes the regenerative braking return energy of electrified railways, such as using the "return without counting" or even "return plus counting" metering method to calculate the electricity bill of traction power supply users. In order to reduce the return amount of regenerative braking energy, a technical solution of energy storage is proposed to store the regenerative braking energy and release it during traction. Most of the existing technical solutions are to set up two sets of energy storage devices in the two power supply arms respectively. It depends on the regenerative working conditions of the two power supply arms, requires a large capacity of the energy storage device, and has a large investment, while the actual metering value is much less than the sum of the regenerative braking energy of the two arms. Most importantly, it cannot directly use the regenerative braking energy in the traction power supply system, nor can it solve the problem of electrical phase separation. In addition, the traction load of electrified railways fluctuates violently. The load power peak not only causes technical problems with negative-sequence power quality, but also increases the capacity demand of traction transformers, bringing a lot of capacity electricity charges to traction depots. Reasonable elimination of traction load peaks can not only improve traction power quality, but also reduce electricity costs of traction depots.

[0003] Combining the same-phase power supply technology and energy storage technology can further improve the performance of traction power supply. At present, there are some patented traction power supply solutions based on same-phase fusion energy storage, and their energy storage devices are generally connected to the DC bus of the same-phase converter. In this type of solution, the DC bus structure of the same-phase converter and the bus voltage level will affect the configuration of the energy storage device. For example, the same-phase converter using high-voltage cascade topology has a large number of DC buses and belongs to high-voltage electricity. Correspondingly, multiple energy storage branches need to be configured, and the insulation of each branch energy storage device must be designed according to the high-voltage insulation standard, which increases the technical difficulty and cost, and also affects the independence and flexibility of the energy storage configuration to a certain extent.

[0004] The same-phase power supply technology can make the feedback power of the locomotive be directly used by the locomotive in the traction condition in the traction network to the maximum extent, which is conducive to reducing the capacity requirements of the traction transformer and energy storage; and the energy storage device can perform peak load shaving and valley filling of the traction load, further reducing the capacity requirements of the traction transformer, and peak shaving can reduce negative sequence. How to combine the same-phase power supply and energy storage technology in the best way is a hot topic in the industry. Summary of the invention

[0005] The first aspect of the purpose of the present invention is to provide an electrified railway same-phase energy storage power supply system, which can effectively solve the technical problem of energy storage in the same-phase power supply system.

[0006] The objective of the present invention is achieved through the following technical solutions: an electrified railway co-phase energy storage power supply system, comprising a traction main transformer, a voltage transformer arranged on a co-phase power supply bus and a current transformer measuring end arranged on a feeder are respectively connected to a detection signal input end of a measurement and control unit, one end of a traction side winding of the traction main transformer is grounded, and the other end is connected to the co-phase power supply bus, and the co-phase power supply bus is connected to a traction network through a feeder; a first traction matching transformer converter side winding 2a is arranged in n groups, a co-phase converter is arranged in n groups, and a first traction matching transformer converter side winding 2a is arranged in n groups; a first traction matching transformer converter side winding 2a ... The n groups of current conversion side windings 2a of the traction matching transformer are connected one-to-one with the parallel side ports of the n groups of in-phase converters, and the series side ports of the in-phase converters are cascaded and connected to the secondary winding of the high-voltage matching transformer; the second traction matching transformer current conversion side windings 3b are set to m groups, and the energy storage converter and energy storage are both set to m groups. The m groups of current conversion side windings 3b of the second traction matching transformer are connected one-to-one with the AC side ports of the m groups of energy storage converters, and the DC side ports of the m groups of energy storage converters are connected one-to-one with the m groups of energy storage devices, wherein n≥1, m≥1;

[0007] The control signal output end of the measurement and control unit is respectively connected to the control end of each in-phase converter and the control end of each energy storage converter;

[0008] One end of the traction side winding of the first traction matching transformer is grounded, and the other end is connected to the same-phase power supply bus; one end of the traction side winding of the second traction matching transformer is grounded, and the other end is connected to the same-phase power supply bus;

[0009] Alternatively, the first traction matching transformer and the second traction matching transformer share the same traction side winding, one end of the shared traction side winding is grounded, and the other end is connected to the same-phase power supply bus.

[0010] The voltage transformer and current transformer measuring ends are respectively connected to the detection signal input end of the measurement and control unit, and the control signal output end of the measurement and control unit is respectively connected to the control end of each in-phase converter and the control end of each energy storage converter;

[0011] Furthermore, the primary winding of the traction main transformer and the primary winding of the high-voltage matching transformer are SCOTT connected or Vv connected.

[0012] Furthermore, the energy storage medium of the energy storage device is one of electromagnetic energy storage, physical energy storage and electrochemical energy storage.

[0013] Furthermore, the voltage transformer is used to measure the voltage of the same-phase power supply bus, and the current transformer is used to measure the current of the feeder.

[0014] The second aspect of the present invention is to provide a control method for controlling the above-mentioned electrified railway co-phase energy storage power supply system, which can effectively solve the technical problem of energy storage converter management and control.

[0015] The purpose of the present invention is achieved by a measurement and control unit. The permissible value of the negative sequence power of the power grid P is known. N and traction load peak-valley threshold P V , the control method comprises:

[0016] Respectively obtain voltage data and current data transmitted by the voltage transformer and the current transformer;

[0017] Calculate the active power S of the traction load according to the voltage data and the current data;

[0018] Judgment 1: Determine whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter to discharge the energy storage and enter judgment 2, otherwise enter judgment 3;

[0019] Judgment 2: Judgment of the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the same-phase converter to provide supply power P S , otherwise, the same-phase converter is controlled to provide zero supply power, where P N >0,P V >0;

[0020] Judgment three: judge whether the active power S of the traction load is less than zero. If so, control the energy storage converter to charge the energy storage and control the same-phase converter to provide a supply power of zero. Otherwise, control the energy storage converter to charge the energy storage and enter judgment two.

[0021] Further, when making a judgment, the energy storage converter is controlled to discharge the energy storage device at a discharge power S D =SP V .

[0022] Furthermore, when making the second judgment, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , control the same-phase converter to provide supply power P S The value of (P V -P N ) / 2.

[0023] Furthermore, when the third judgment is made, if the active power S of the traction load is less than zero, the energy storage converter is controlled so that the charging power S of the energy storage device is C=-S, if the active power S of the traction load is greater than zero, the energy storage converter is controlled to make the charging power S of the energy storage device C =P V -S.

[0024] The third aspect of the present invention is to provide a measurement and control unit for implementing the above control method, which can effectively solve the technical problems of calculation and judgment in the control method.

[0025] The measurement and control unit according to the third aspect of the present invention comprises a data acquisition module, a calculation module, a first judgment module, a second judgment module and a third judgment module:

[0026] The data acquisition module is used to acquire the voltage data and current data transmitted by the voltage transformer and the current transformer;

[0027] Calculation module: used for calculating the active power S of the traction load according to the voltage data and the current data;

[0028] The first judgment module is used to judge whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter to discharge the energy storage and enter the second judgment module, otherwise enter the third judgment module;

[0029] The second judgment module is used to judge the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the same-phase converter to provide supply power P S , otherwise, the same-phase converter is controlled to provide zero supply power;

[0030] The third judgment module: judge whether the active power S of the traction load is less than zero. If so, control the energy storage converter to charge the energy storage and control the same-phase converter to provide zero supply power. Otherwise, control the energy storage converter to charge the energy storage and enter the second judgment module.

[0031] Furthermore, in the first judgment module, the energy storage converter is controlled to discharge the energy storage device at a discharge power S D =SP V ;

[0032] In the second judgment module, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , control the same-phase converter to provide supply power P S The value of (P V -P N ) / 2;

[0033] In the third judgment module, if the traction load active power S is less than zero, the energy storage converter is controlled to make the charging power S of the energy storage device C =-S, if the active power S of the traction load is greater than zero, the energy storage converter is controlled to make the charging power S of the energy storage device C =P V -S.

[0034] The advantages and effects of the present invention compared with the prior art are: the energy storage converter controls the charging and discharging of the energy storage, and its circuit does not pass through the same-phase converter. The energy storage converter and the same-phase converter are set separately and work in coordination. The energy storage converter is used preferentially to control the energy storage to shave peaks and fill valleys. When the negative sequence does not meet the standard, the same-phase converter performs negative sequence compensation to meet the standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of the first electrified railway co-phase energy storage and power supply system of the present invention.

[0036] Figure 2 It is a structural schematic diagram of the second electrified railway co-phase energy storage power supply system of the present invention.

[0037] Figure 3 It is a structural schematic diagram of the third electrified railway co-phase energy storage power supply system of the present invention.

[0038] Figure 4 It is a schematic diagram of the first traction matching transformer and the second traction matching transformer of the present invention sharing the same traction winding.

[0039] Figure 5 It is a structural schematic diagram of a specific electrified railway co-phase energy storage and power supply system of the present invention.

[0040] Figure 6 The present invention is a flow chart of a control method for a co-phase energy storage power supply system for an electrified railway.

[0041] Figure 7 This is a structural block diagram of a measurement and control unit of the present invention. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0043] Example 1

[0044] like Figure 1 As shown, this embodiment provides an electrified railway co-phase energy storage power supply system, including a traction main transformer 1, a first traction matching transformer 2, a second traction matching transformer 3, a co-phase converter 4, an energy storage converter 5, an energy storage 6, a measurement and control unit 7, a co-phase power supply bus 8, a feeder 9, a voltage transformer 10, a current transformer 11 and a high-voltage matching transformer 12, wherein:

[0045] One end of the traction side winding of the traction main transformer 1 is grounded, and the other end is connected to the same-phase power supply bus 8, and the same-phase power supply bus 8 is connected to the traction network through a feeder 9;

[0046] The first traction matching transformer 2 is provided with n groups of conversion side windings 2a, and n groups of in-phase converters 4 are provided. The n groups of conversion side windings 2a of the first traction matching transformer 2 are connected to the parallel side ports of the n groups of in-phase converters 4 in a one-to-one correspondence. The series side ports of the in-phase converters 4 are cascaded and connected to the secondary winding of the high-voltage matching transformer 12.

[0047] The second traction matching transformer 3 is provided with m groups of converter side windings 3b, and the energy storage converter 5 and the energy storage device 6 are provided with m groups. The m groups of converter side windings 3b of the second traction matching transformer 3 are connected to the m groups of AC side ports of the energy storage converter 5 in a one-to-one correspondence, and the m groups of DC side ports of the energy storage converter 5 are connected to the m groups of energy storage devices 6 in a one-to-one correspondence; wherein, n≥1, m≥1.

[0048] The measuring ends of the voltage transformer 10 and the current transformer 11 are respectively connected to the detection signal input end of the measurement and control unit 7 , and the control signal output end of the measurement and control unit 7 is respectively connected to the control end of each in-phase converter 4 and the control end of each energy storage converter 5 .

[0049] One end of the traction side winding of the first traction matching transformer 2 is grounded, and the other end is connected to the same-phase power supply bus 8; one end of the traction side winding of the second traction matching transformer 3 is grounded, and the other end is connected to the same-phase power supply bus 8;

[0050] Or the first traction matching transformer 2 and the second traction matching transformer 3 share the same traction side winding, one end of the shared traction side winding is grounded, and the other end is connected to the same-phase power supply bus 8.

[0051] In this embodiment, there are two schemes for setting the first traction matching transformer 2 and the second traction matching transformer 3. One scheme is to set the traction side winding of the first traction matching transformer 2 and the traction side winding of the second traction matching transformer 3 separately, that is, one end of the traction side winding of the first traction matching transformer 2 is grounded, and the other end is connected to the same-phase power supply bus 8, and one end of the traction side winding of the second traction matching transformer 3 is grounded, and the other end is connected to the same-phase power supply bus 8. Figure 1 , Figure 2 and Figure 3 As shown; Another solution is to integrate the traction side winding of the first traction matching transformer 2 and the traction side winding of the second traction matching transformer 3 into the same traction side winding, that is, the first traction matching transformer 2 and the second traction matching transformer 3 share the same traction side winding, one end of the shared traction side winding is grounded, and the other end is connected to the same-phase power supply bus 8, as shown Figure 4As shown, the advantage of doing so is that it can save the transformer's floor space and also save the transformer's cost.

[0052] The energy storage device 6, the energy storage converter 5 and the second traction matching transformer 3 in this embodiment together form an energy storage branch and are connected to the same-phase power supply bus 8. The charging and discharging process of the energy storage branch does not pass through the same-phase converter 4, so it will not occupy the capacity of the same-phase converter 4. The port DC voltage of the energy storage device 7 is also not affected by the structure and voltage of the DC bus in the middle of the same-phase converter. In addition, the energy storage device 6, the energy storage converter 5 and the second traction matching transformer 3 are set as an independent energy storage branch, which not only makes the interface configuration of the energy storage converter 5 and various energy storage devices 6 more flexible, but also facilitates the expansion of the number of energy storage branches. The measurement and control unit 7 can achieve the goal of optimal utilization of the feedback energy of the electric locomotive, suppressing the peak power of the traction station, controlling the negative sequence of the three-phase power grid, and reducing the capacity demand of the traction transformer by reasonably controlling the power supplied by the same-phase converter 4 and the charging and discharging power of the energy storage converter 5. In this embodiment, the energy storage medium of the energy storage device 6 can be one of electromagnetic energy storage, physical energy storage and electrochemical energy storage.

[0053] It should be noted that the in-phase converter 4 in this embodiment is an AC-DC-AC converter, the port connected to the high-voltage matching transformer 12 is called a series side port, the port connected to the traction matching transformer 2 is called a parallel side port, and the energy storage converter 5 is an AC-DC converter. When implementing this embodiment, the values ​​of m and n may not be equal and can be set according to actual conditions.

[0054] Preferably, the primary winding of the traction main transformer 1 and the primary winding of the high-voltage matching transformer 12 can be connected to form a SCOTT connection, such as Figure 1 As another preferred embodiment, the high voltage matching transformer 12 may be a Yd connection, such as Figure 2 As another preferred embodiment, the primary winding of the traction main transformer 1 and the primary winding of the high-voltage matching transformer 12 can be connected to form a Vv connection, such as Figure 3 As shown; in addition, the primary winding of the traction main transformer 1 and the primary winding of the high-voltage matching transformer 12 can also be connected in a Vx connection manner.

[0055] Preferably, the voltage transformer 10 is used to measure the voltage of the same-phase power supply bus 8 , and the current transformer 11 is used to measure the current of the feeder 9 .

[0056] Specifically, Figure 5 As shown, taking SCOTT connection, n=m=1, and the first traction matching transformer 2 and the second traction matching transformer 3 sharing the same traction winding as an example, this embodiment can be connected in the following manner:

[0057] The primary side of the traction main transformer 1 is connected to two phases of the three-phase power grid A, B, and C with a middle tap. One end of the secondary winding of the traction main transformer 1 is connected to the same-phase power supply bus 8, and the other end is grounded. The same-phase power supply bus 8 is connected to the traction grid via a feeder 9 to supply power to the train.

[0058] One end of the primary side of the high-voltage matching transformer 12 is connected to the third phase of the three-phase grid A, B, C (another phase other than the two phases connected to the traction main transformer 1), and the other end is connected to the middle tap of the primary winding of the traction main transformer 1, together forming a Scott connection; the secondary winding of the high-voltage matching transformer 12 is connected to the series side port of the same-phase converter 4;

[0059] The first traction matching transformer 2 and the second traction matching transformer 3 share the same traction side winding, one end of the traction side winding is connected to the same-phase power supply bus 8, and the other end is grounded; the conversion side winding 2a of the first traction matching transformer 2 is connected to the parallel side port of the same-phase converter 4, and the conversion side winding 3b of the second traction matching transformer 3 is connected to the AC port of the energy storage converter 4; the DC port of the energy storage converter 4 is connected to the port of the energy storage 6;

[0060] The detection signal input end of the measurement and control unit 7 is respectively connected to the voltage transformer 10 and the current transformer 11, and the control signal output end thereof is respectively connected to the control end of the in-phase converter 4 and the control end of the energy storage converter 5; the voltage transformer 10 measures the voltage of the in-phase power supply bus 8, and the current transformer 11 measures the current of the feeder 9;

[0061] The measurement and control unit 7 measures the traction load power s via the voltage transformer 10 and the current transformer 11 , and controls the current and power of the in-phase converter 3 and the energy storage converter 4 accordingly.

[0062] Example 2

[0063] like Figure 6 As shown, this embodiment provides a control method for controlling the electric railway co-phase energy storage power supply system provided in Example 1, which is applied to the measurement and control unit, and the grid negative sequence power allowable value P is known. N and traction load peak-valley threshold P V , the control method comprises:

[0064] A1: respectively obtaining voltage data and current data transmitted by the voltage transformer 10 and the current transformer 11;

[0065] A2: Calculate the active power S of the traction load based on the voltage data and current data;

[0066] A3: Judgment 1: Determine whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter 5 to discharge the energy storage device 6 and enter judgment 2, otherwise enter judgment 3;

[0067] A4: Judgment 2: Judgment of the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the in-phase converter 4 to provide supply power P S , otherwise, control the in-phase converter 4 to provide a supply power of zero;

[0068] A5: Judgment three: judge whether the active power S of the traction load is less than zero. If so, control the energy storage converter 5 to charge the energy storage 6 and control the same-phase converter 4 to provide zero supply power. Otherwise, control the energy storage converter 5 to charge the energy storage 6 and enter judgment two, where P N >0,P V >0.

[0069] As a preference, this embodiment further includes: when making a judgment, controlling the energy storage converter 5 to discharge the energy storage device 6 with a discharge power S D =SP V .

[0070] As a preferred embodiment, this embodiment further includes: when performing the second judgment, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , controls the in-phase converter 4 to provide the supply power P S The value of (P V -P N ) / 2.

[0071] As a preferred embodiment, the present embodiment further comprises: when performing judgment three, if the active power S of the traction load is less than zero, controlling the energy storage converter 5 to make the charging power S of the energy storage device 6 C =-S, if the active power S of the traction load is greater than zero, the energy storage converter 5 is controlled to make the charging power S of the energy storage device 6 C =P V -S.

[0072] When implementing this embodiment, the energy storage inverter 5 controls the charging and discharging of the energy storage 6, and its circuit does not pass through the same-phase inverter 4. The energy storage inverter 5 and the same-phase inverter 4 are set separately and work in coordination. The energy storage inverter 5 is used preferentially to control the energy storage 6 to shave peaks and fill valleys. When the negative sequence does not meet the standard, the same-phase inverter 4 performs negative sequence compensation to meet the standard.

[0073] It should be noted here that the allowable value of negative sequence power of the power grid P N Determined by the grid capacity, as the basis for compensation, the traction load peak-valley threshold P VThe goal is to reduce the basic electricity fee. In this embodiment, when the power factor is equal to 1, the same-phase energy storage power supply system does not need to perform reactive power compensation. When the power factor is not equal to 1, the same-phase energy storage power supply system can be controlled to perform reactive power compensation.

[0074] In addition, in this embodiment, the charging and discharging rated power Se can be set. When according to the formula S D =SP V When the calculated result is greater than Se, let S D =Se; Similarly, when according to the formula S C =-S or S C =P V -When the result calculated by S is greater than Se, let S C =Se. The reason for this is that, considering the actual situation and economy, the power of the energy storage co-phase power supply system should not be too large.

[0075] Example 3

[0076] like Figure 7 As shown, this embodiment provides a measurement and control unit for implementing the control method described in Embodiment 2, including:

[0077] Data acquisition module: used to acquire voltage data and current data transmitted by the voltage transformer 10 and the current transformer 11;

[0078] Calculation module: used to calculate the active power S of the traction load according to the voltage data and the current data;

[0079] The first judgment module is used to judge whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter 5 to discharge the energy storage device 6 and enter the second judgment module, otherwise enter the third judgment module;

[0080] The second judgment module is used to judge the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the in-phase converter 4 to provide supply power P S , otherwise, control the in-phase converter 4 to provide a supply power of zero;

[0081] The third judgment module: judge whether the active power S of the traction load is less than zero. If so, control the energy storage converter 5 to charge the energy storage device 6 and control the in-phase converter 4 to provide a supply power of zero. Otherwise, control the energy storage converter 5 to charge the energy storage device 6 and enter the second judgment module.

[0082] As a preferred embodiment, in the first judgment module, the energy storage converter 5 is controlled to discharge the energy storage device 6 with a discharge power S D =SP V ;

[0083] In the second judgment module, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , controls the in-phase converter 4 to provide the supply power P S The value of (P V -P N ) / 2;

[0084] In the third judgment module, if the active power S of the traction load is less than zero, the energy storage converter 5 is controlled to make the charging power S of the energy storage device 6 C =-S, if the active power S of the traction load is greater than zero, the energy storage converter 5 is controlled to make the charging power S of the energy storage device 6 C =P V -S.

[0085] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An electrified railway co-phase energy storage power supply system, comprising a traction main transformer (1), a voltage transformer (10) arranged on a co-phase power supply bus (8) and a current transformer (11) arranged on a feeder (9), the measuring ends of which are respectively connected to the detection signal input end of a measurement and control unit (7), one end of a traction side winding of the traction main transformer (1) is grounded, and the other end is connected to the co-phase power supply bus (8), and the co-phase power supply bus (8) is connected to a traction network through a feeder (9), characterized in that: The first traction matching transformer (2) has n groups of current conversion side windings 2a, and n groups of in-phase converters (4). The n groups of current conversion side windings 2a of the first traction matching transformer 2 are connected one-to-one with the parallel side ports of the n groups of in-phase converters (4). The series side ports of the in-phase converters (4) are connected in cascade connection with the secondary windings of the high-voltage matching transformer (12). The second traction matching transformer (3) has m groups of current conversion side windings 3b, and the energy storage converter (5) and the energy storage device (6) are both provided with m groups. The m groups of current conversion side windings 3b of the second traction matching transformer (3) are connected one-to-one with the AC side ports of the m groups of energy storage converters (5), and the DC side ports of the m groups of energy storage converters (5) are connected one-to-one with the m groups of energy storage devices (6); wherein n≥1, m≥1; The control signal output end of the measurement and control unit (7) is respectively connected to the control end of each in-phase converter (4) and the control end of each energy storage converter (5); One end of the traction side winding of the first traction matching transformer (2) is grounded, and the other end is connected to the same-phase power supply bus (8); one end of the traction side winding of the second traction matching transformer (3) is grounded, and the other end is connected to the same-phase power supply bus (8); Alternatively, the first traction matching transformer (2) and the second traction matching transformer (3) share the same traction side winding, one end of the shared traction side winding is grounded, and the other end is connected to the same-phase power supply bus (8).

2. The same-phase energy storage power supply system for an electrified railway according to claim 1, characterized in that: The primary winding of the traction main transformer (1) and the primary winding of the high-voltage matching transformer (12) are SCOTT connections or Vv connections.

3. The same-phase energy storage power supply system for an electrified railway according to claim 1, characterized in that: The energy storage medium of the energy storage device (6) is one of electromagnetic energy storage, physical energy storage and electrochemical energy storage.

4. The same-phase energy storage power supply system for an electrified railway according to claim 1, characterized in that: The voltage transformer (10) is used to measure the voltage of the same-phase power supply bus (8), and the current transformer (11) is used to measure the current of the feeder (9).

5. A control method for controlling the electric railway co-phase energy storage power supply system according to any one of claims 1 to 4, implemented by a measurement and control unit (7), characterized in that: The permissible value of negative sequence power of the known power grid is P N and traction load peak-valley threshold P V , the control method comprises: Respectively acquiring voltage data and current data transmitted by a voltage transformer (10) and a current transformer (11); Calculate the active power S of the traction load according to the voltage data and the current data; Judgment 1: Determine whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter (5) to discharge the energy storage device (6) and enter judgment 2, otherwise enter judgment 3; Judgment 2: Judgment of the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the in-phase converter (4) to provide the supply power P S , otherwise, the in-phase converter (4) is controlled to provide a supply power of zero; wherein, P N >0,P V >0; Judgment three: judge whether the active power S of the traction load is less than zero. If so, control the energy storage converter (5) to charge the energy storage device (6) and control the same-phase converter (4) to provide a supply power of zero. Otherwise, control the energy storage converter (5) to charge the energy storage device (6) and enter judgment two.

6. The method for controlling a co-phase energy storage power supply system for an electrified railway according to claim 5, characterized in that: When making a judgment, the energy storage converter (5) is controlled to discharge the energy storage device (6) at a discharge power S D =SP V .

7. The method for controlling a co-phase energy storage power supply system for an electrified railway according to claim 5, characterized in that: When making the second judgment, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , controls the in-phase converter (4) to provide the supply power P S The value of (P V -P N ) / 2.

8. The method for controlling a co-phase energy storage power supply system for an electrified railway according to claim 5, characterized in that: When making the third judgment, if the active power S of the traction load is less than zero, the energy storage converter (5) is controlled so that the charging power S of the energy storage device (6) is C = -S, if the active power S of the traction load is greater than zero, the energy storage converter (5) is controlled to make the charging power S of the energy storage device (6) C =P V -S.

9. A measurement and control unit for implementing the control method according to any one of claims 5 to 8, characterized in that: include: A data acquisition module: used for acquiring voltage data and current data transmitted by a voltage transformer (10) and a current transformer (11); Calculation module: used for calculating the active power S of the traction load according to the voltage data and the current data; The first judgment module is used to judge whether the traction load active power S is greater than the traction load peak-valley threshold P V If yes, control the energy storage converter (5) to discharge the energy storage device (6) and enter the second judgment module, otherwise enter the third judgment module; The second judgment module is used to judge the peak-valley threshold value P of the traction load V Is it greater than the allowable value P of the negative sequence power of the power grid? N If yes, control the in-phase converter (4) to provide the supply power P S , otherwise, controlling the in-phase converter (4) to provide a supply power of zero; The third judgment module: judges whether the active power S of the traction load is less than zero. If so, controls the energy storage converter (5) to charge the energy storage device (6) and controls the same-phase converter (4) to provide a supply power of zero. Otherwise, controls the energy storage converter (5) to charge the energy storage device (6) and enters the second judgment module.

10. A measurement and control unit according to claim 9, characterized in that: In the first judgment module, the energy storage converter (5) is controlled to discharge the energy storage device (6) with a discharge power S D =SP V ; In the second judgment module, if the traction load peak-valley threshold P V Greater than the allowable value of the negative sequence power of the power grid P N , controls the in-phase converter (4) to provide the supply power P S The value of (P V -P N ) / 2; In the third judgment module, if the active power S of the traction load is less than zero, the energy storage converter (5) is controlled to make the charging power S of the energy storage device (6) C = -S, if the active power S of the traction load is greater than zero, the energy storage converter (5) is controlled to make the charging power S of the energy storage device (6) C =P V -S.

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