CN110829435B - Electrified railway energy storage type traction power supply system and control method thereof - Google Patents
Electrified railway energy storage type traction power supply system and control method thereof Download PDFInfo
- Publication number
- CN110829435B CN110829435B CN201910955379.4A CN201910955379A CN110829435B CN 110829435 B CN110829435 B CN 110829435B CN 201910955379 A CN201910955379 A CN 201910955379A CN 110829435 B CN110829435 B CN 110829435B
- Authority
- CN
- China
- Prior art keywords
- power
- energy storage
- traction
- ref
- storage system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L7/00—Electrodynamic brake systems for vehicles in general
- B60L7/10—Dynamic electric regenerative braking
- B60L7/14—Dynamic electric regenerative braking for vehicles propelled by ac motors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L9/00—Electric propulsion with power supply external to the vehicle
- B60L9/16—Electric propulsion with power supply external to the vehicle using ac induction motors
- B60L9/24—Electric propulsion with power supply external to the vehicle using ac induction motors fed from ac supply lines
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
- H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
Abstract
The invention discloses an energy storage type traction power supply system of an electrified railway and a control method thereof, wherein the system comprises a power flow controller, an energy storage system and a single-phase main traction transformer, wherein the power flow controller comprises a high-voltage matching transformer, a power grid side AC-DC converter, a traction test AC-DC converter, a middle DC side capacitor and a traction matching transformer; the energy storage system comprises a bidirectional DC/DC converter and an energy storage element, wherein the energy storage element is connected in parallel to the middle direct-current side capacitor through the bidirectional DC/DC converter; acquiring voltage and current data of a load at an outlet of a substation, judging the operation condition of the system, and calculating the compensation power of ports of a power flow controller and an energy storage device under each condition; adding the power signal into a power outer ring and a current inner ring for double-ring control to obtain a modulation signal; and then generating a switching signal of the control device through PWM modulation. The invention realizes the recovery and the reutilization of the regenerative braking energy of the train, improves the utilization rate of the regenerative braking energy, and realizes the negative sequence electric energy quality control and the capacity optimization of the compensating device.
Description
Technical Field
The invention relates to the technical field of traction power supply of electrified railways, in particular to an energy storage type traction power supply system of an electrified railway and a control method thereof.
Background
The single-phase power frequency alternating current power supply system of the electrified railway and the characteristics of high power and asymmetry of traction load cause the problem of electric energy quality of the system mainly based on negative sequence, and influence the safe, reliable and efficient operation of the electrified railway. Meanwhile, as the trunk line of the electrified railway extends to western high-altitude areas in China, the situations that the gradient of the line is large, the number of tunnels is large, and the regenerative braking of the train is frequent often occur. For example, the maximum gradient of the passenger dedicated line in Baolan and the passenger dedicated line in West Cheng can reach 25 per thousand, and the bridge-tunnel ratio in the greenish section can reach more than 90 percent. On the one hand, the peak load power is increased when the train climbs a slope, so that the rated capacity of the traction transformer is increased, but the utilization rate of the traction transformer is low and the economical efficiency is poor due to the low load rate of the traction transformer; on the other hand, more regenerative braking energy can be generated in the process of braking the train downhill, and the braking energy is returned to the power grid or is consumed by energy consumption elements, so that the influence on the power grid is caused, and the waste of electric energy is also caused.
Theories and practices show that the active compensation technology can effectively solve the negative sequence power quality problem existing in the electrified railway; the energy storage technology can realize the functions of demand side electric energy management, peak clipping and valley filling and smooth load. Therefore, the research of the energy storage type traction power supply scheme is developed, the active compensation technology and the energy storage technology are combined, and the advantages of the active compensation technology and the energy storage technology are fully utilized, so that the purposes of comprehensive negative sequence management, efficient utilization of regenerative braking energy and optimal configuration of system capacity are achieved, and the method has important practical significance for improving the power supply quality, the power supply efficiency and the economic benefit of a traction power supply system.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide an energy storage type traction power supply system for an electrified railway and a control method thereof, which can be applied to a single-phase ac traction power supply system, and can achieve comprehensive negative sequence power quality management, efficient utilization of regenerative braking energy, optimal configuration of system capacity, and reduce system operation cost. The technical scheme is as follows:
an energy storage type traction power supply system of an electrified railway comprises a power flow controller, an energy storage system and a single-phase main traction transformer; the power flow controller comprises a high-voltage matching transformer, a power grid side AC-DC converter, a traction side AC-DC converter, a middle DC side capacitor and a traction matching transformer; the high-voltage matching transformer has a primary side connected to the power grid side and a secondary side connected to the input end of the power grid side AC-DC converter, and the output end of the power grid side AC-DC converter is connected to the input end of the traction side AC-DC converter through a middle DC side capacitor to form a back-to-back structure; the output end of the traction side AC-DC converter is connected to the primary side of a traction matching transformer, and the secondary side of the traction matching transformer is connected to the traction side; the energy storage system comprises a bidirectional DC/DC converter and energy storage elements (including but not limited to a super capacitor, a storage battery and the like), wherein the energy storage elements are connected in parallel to a middle direct-current side capacitor through the bidirectional DC/DC converter; the primary side of the single-phase main traction transformer is connected to the power grid side, and the secondary side of the single-phase main traction transformer is connected to the traction side and forms connection with the high-voltage matching transformer.
Furthermore, the power grid side AC-DC converter and the traction side AC-DC converter adopt structures such as H-bridge cascade, MMC or two levels and the like.
A control method of an electrified railway energy storage type traction power supply system comprises the following steps:
step 1: three-phase unbalance u satisfied by transformer ε For constraint, the working mode of the system is divided into three modes of regenerative braking, peak clipping discharging and valley filling charging according to the magnitude of traction load;
step 2: voltage U of load at outlet of collection substation L And current data I L Calculating to obtain the instantaneous power P of the load L ；
And step 3: based on system working mode division principle and load instantaneous power P obtained through calculation L To judge thisThe system operates the working condition;
and 4, step 4: based on the system operation condition obtained by judgment, calculating the power reference value p of the power flow controller power grid side and traction side port under the condition α_ref And p β_ref And an energy storage system port power reference p ES_ref ，
And 5: obtaining the current reference values i of the power grid side and the traction side port of the power flow controller through a power outer ring α_ref And i β_ref And a reference value of the port current i of the energy storage system ES_ref ；
And 6: respectively reference the port current of the power flow controller to a value i α_ref And i β_ref And a reference value of the port current i of the energy storage system ES_ref And the actually measured current values i of the grid side and the traction side ports of the power flow controller α And i β And energy storage system port current value i ES Generating a modulation signal through a current inner loop;
and 7: and performing PWM modulation on the obtained modulation signal to generate a switching signal for controlling the power flow controller and the energy storage system, performing system coordination control, and completing system power transfer under each working condition.
Further, the system working mode division principle and the method for determining the port power of the power flow controller and the energy storage system in each working mode are as follows:
a: if the load power P L When the energy storage system is smaller than zero, the train works in a regenerative braking state, the system runs in a regenerative braking working mode, and the energy storage system is used for storing and absorbing the regenerative braking energy of the train;
a1) if the train regenerates the braking power | P L |＜P ESM When the system is running in the first working condition of the regenerative braking energy control mode, wherein P is ESM The maximum charge and discharge power of the energy storage system is preset; at the moment, all regenerative braking energy is absorbed by the energy storage system through the traction side AC-DC converter to obtain a port power reference value P of the power flow controller α_ref And P β_ref Port power reference value P of energy storage system ES_ref And port power reference value P of single-phase main traction substation T_ref Comprises the following steps:
a2) if the train regenerates the braking power P ESM ＜|P L |＜P ESM +P Low When the system is running, the system is in the second working condition of the regenerative braking energy control mode, wherein P Low Switching threshold value for preset valley filling mode, wherein the threshold value is the unbalance degree u of three-phase voltage required to be met by power transformation ε (%) short circuit capacity S of power system connected with substation d The product of (a); at the moment, the regenerative braking energy passes through the traction side AC-DC converter and is charged and discharged from the energy storage system at the maximum power P ESM Absorbing and returning the residual regenerative braking energy to the three-phase power grid from the single-phase main traction transformer to obtain a port power reference value P of the power flow controller α_ref And P β_ref Port power reference value P of energy storage system ES_ref And a port power reference value P of the single-phase main traction substation T_ref Comprises the following steps:
a3) if the regenerative braking power of the train is | P L |＞P ESM +P Low When the system is in the regenerative braking energy control mode, the system operates in a third working condition; at the moment, the regenerative braking energy passes through the traction side AC-DC converter and is charged and discharged from the energy storage system at the maximum power P ESM Absorbing and returning the residual regenerative braking energy to the three-phase power grid through a single-phase main traction transformer and a power grid side AC-DC converter, and obtaining a port power reference value P of the power flow controller in order to ensure that the system negative sequence meets the national standard limit value α_ref And P β_ref And a port power reference value P of the energy storage system ES_ref And port power reference value P of single-phase main traction substation T_ref Comprises the following steps:
B) if the load power P L If the load is larger than zero, the train works in a traction state, the system runs in a traction working mode, and the energy storage system is used for peak clipping and valley filling of traction load;
b1) if the train pulls the power P L ＜P ESM When the system is operated in a valley filling charging mode, working condition I is carried out; at the moment, the traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer, the energy storage system is charged by the three-phase power grid through a traction side AC-DC converter with the same power as the train traction power, and a port power reference value P of the power flow controller is obtained α_ref And P β_ref Port power reference value P of energy storage system ES_ref And port power reference value P of single-phase main traction substation T_ref Comprises the following steps:
b2) if the train pulls the power P ESM ＜P L ＜P Low When the system is operated in a valley filling charging mode working condition II; at the moment, the traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer, the energy storage system is charged by the three-phase power grid through a power grid side AC-DC converter at the maximum charging power, and a port power reference value P of the power flow controller is obtained α_ref And P β_ref Port power reference value P of energy storage system ES_ref And a port power reference value P of the single-phase main traction substation T_ref Comprises the following steps:
b3) if the train pulls the power P Low ＜P L ＜P H In time, the system operates in a peak clipping discharge mode condition one, wherein P H Switching a threshold value for a preset peak clipping mode; at the moment, the energy storage system does not work, and the traction power required by the train is obtained by a three-phase power grid through a tidal current controller and a single-phase main tractionThe power flow controller plays a role of peak clipping, and a port power reference value P of the power flow controller is obtained in order to enable the negative sequence of the system to meet the national standard limit value α_ref And P β_ref Port power reference value P of energy storage system ES_ref And port power reference value P of single-phase main traction substation T_ref Comprises the following steps:
b4) if the train pulls the power P L ＞P H When the system is in the peak clipping discharge mode, operating the system in a second working condition; at this time, the energy storage system has the maximum discharge power P ESM Supplying power to the train, wherein the residual traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer and a power flow controller, wherein the energy storage system and the power flow controller share the function of peak clipping, and meanwhile, in order to ensure that the negative sequence of the system meets the national standard limit value, a port power reference value P of the power flow controller is obtained α_ref And P β_ref Port power reference value P of energy storage system ES_ref And a port power reference value P of the single-phase main traction substation T_ref Comprises the following steps:
the beneficial effects of the invention are:
1) the invention effectively utilizes the energy storage system to recover and reuse the regenerative braking energy generated by the train and improves the utilization rate of the regenerative braking energy.
2) The invention utilizes the energy storage system and the power flow controller to carry out peak clipping on the peak load, thereby realizing negative sequence power quality control while reducing the electric charge.
3) The method has good effect on the negative sequence compensation of the system, has universal applicability when performing negative sequence compensation, can perform complete compensation and can also perform optimized compensation, and if the optimized compensation is performed, the capacity of the device can be effectively reduced, and the investment cost is reduced.
Drawings
FIG. 1 is a schematic diagram of a main circuit structure of an energy storage type traction power supply system; in the figure: 1-a power flow controller; 2-an energy storage system; 3-single phase main traction transformer; 4-high voltage matching transformer; 5-a traction matching transformer; 6-a grid side AC-DC converter; 7-a traction side AC-DC converter; 8-intermediate dc side capacitance; 9-a bidirectional DC/DC converter; 10-a super capacitor; 11-the trailing side.
Fig. 2 is a schematic diagram of a topology of an energy storage system.
Fig. 3 is a block diagram of a system coordination control strategy.
Fig. 4 is a flowchart of the system operation mode determination.
FIG. 5 is a diagram of the effect of regenerative braking energy utilization of the system.
FIG. 6 is a diagram illustrating the effect of negative sequence compensation.
Fig. 7 is a diagram showing the effect of reducing the maximum demand of the system.
Detailed Description
The invention is described in further detail below with reference to the figures and specific embodiments. Fig. 1 is a schematic diagram of a main circuit structure of an energy storage type traction power supply system. The system mainly comprises a power flow controller 1, an energy storage system 2 and a single-phase main traction transformer 3. Has the following functions: 1) the power flow controller is matched with the single-phase main traction transformer to work and is used for balancing negative sequence current on the power grid side; 2) the energy storage system and the power flow controller work cooperatively to realize the regenerative braking energy feedback utilization and traction load peak clipping of the train.
The power flow controller 1 comprises a high-voltage matching transformer 4, a power grid side AC-DC converter 6, a traction side AC-DC converter 7, a middle DC side capacitor 8 and a traction matching transformer 5; the primary side of the high-voltage matching transformer 4 is connected to the power grid side, the secondary side of the high-voltage matching transformer is connected to the input end of a power grid side AC-DC converter 6, and the output end of the power grid side AC-DC converter 6 is connected to the input end of a traction side AC-DC converter 7 through a middle DC side capacitor 8 to form a back-to-back structure; the output of the traction side ac-dc converter 7 is connected to the primary side of the traction matching transformer 5, and the secondary side of the traction matching transformer 5 is connected to the traction side 11. The grid side ac-dc converter 6 and the traction side ac-dc converter 7 may adopt an H-bridge cascade, an MMC or a two-level structure. As shown in fig. 1, in this embodiment, the converter adopts an H-bridge cascade topology, which is easy to implement modularization and power expansion, and the dc links are independent from each other, thereby reducing the dc side voltage, reducing the number of series and parallel connections of the energy storage elements, increasing the system reliability, and facilitating the access of the energy storage system.
The energy storage system 2 comprises a bidirectional DC/DC converter and an energy storage element. As shown in fig. 2, in this embodiment, the bidirectional DC/DC converter adopts a half-bridge topology, which is simple in structure, low in switching loss, and low in voltage and current stress; the energy storage element adopts a super capacitor, has high power density, short charging time and long service life, can well adapt to the characteristics of high power and frequent fluctuation of a traction load, and can perform quick high-power charging and discharging. The energy storage element 10 is connected in parallel to the intermediate DC-side capacitor 8 via a bidirectional DC/DC converter 9.
The single-phase main traction transformer 3 is connected to the grid side on the primary side and to the traction side 11 on the secondary side, forming a balanced connection with the high-voltage matching transformer 4.
The control block diagram of the control method of the energy storage type traction power supply system of the electrified railway is shown in fig. 3, and the control method comprises the following steps:
step 1: three-phase unbalance u satisfied by transformer ε For constraint, the working mode of the system is divided into three modes of regenerative braking, peak clipping discharging and valley filling charging according to the magnitude of the traction load.
Step 2: collecting voltage U of load at outlet of substation L And current data I L Calculating to obtain the instantaneous power P of the load L 。
And step 3: and (3) judging the system operation condition at the moment based on the system operation mode division principle and the load instantaneous power obtained in the step (2).
The principle of judging the system operating conditions is shown in fig. 4, and is briefly described as follows:
if the load power P L Less than zero indicates that the train is operating in a regenerative braking state and the system will be operating in regenerationAnd in the braking working mode, the energy storage system is utilized to store and absorb the regenerative braking energy of the train. If the regenerative braking power of the train is | P L |＜P ESM When the system operates in a first working condition of a regenerative braking energy control mode, all regenerative braking energy is absorbed by the energy storage system through the traction side AC-DC converter; if the train regenerates the braking power P ESM ＜|P L |＜P ESM +P Low When the system is in the second working condition of the regenerative braking energy control mode, the regenerative braking energy passes through the traction side AC-DC converter and is charged and discharged from the energy storage system at the maximum power P ESM Absorbing and returning the residual regenerative braking energy to the three-phase power grid through the single-phase main traction transformer; if the regenerative braking power of the train is | P L |＞P ESM +P Low When the system is in the third working condition of the regenerative braking energy control mode, the regenerative braking energy passes through the traction side AC-DC converter and is charged and discharged from the energy storage system at the maximum power P ESM And absorbing and returning the residual regenerative braking energy to the three-phase power grid through the single-phase main traction transformer and the power grid side AC-DC converter.
If the load power P L And if the load is larger than zero, the train works in a traction state, the system runs in a traction working mode, and the energy storage system is used for peak clipping and valley filling of traction load. If the train pulls the power P L ＜P ESM When the system operates in a first valley filling charging mode, the traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer, and the energy storage system is charged by the three-phase power grid through a power grid side AC-DC converter with the same power as the train traction power; if the train pulls the power P ESM ＜P L ＜P Low When the system operates in a valley filling charging mode working condition II, the traction power required by the train is provided by the three-phase power grid through the single-phase main traction transformer, and the energy storage system is charged by the three-phase power grid through the power grid side AC-DC converter at the maximum charging power; if the train pulls the power P Low ＜P L ＜P H When the system is operated in the peak clipping discharge mode working condition I, the energy storage system does not work at the moment, and the traction power required by the train is controlled by the three-phase power grid through the tide currentThe system is provided with a single-phase main traction transformer, wherein the power flow controller plays a role in peak clipping; if the train pulls the power P L ＞P H When the system is in the peak clipping discharge mode, the system operates in the second working condition, and at the moment, the energy storage system uses the maximum discharge power P ESM The power is supplied to the train, the residual traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer and a power flow controller, wherein the energy storage system and the power flow controller share the function of peak clipping.
And 4, step 4: calculating power reference values of ports of the power flow controller and the energy storage system under the working condition based on the system operating condition obtained in the step 3;
wherein, under each operation condition, the power of each device port is as follows:
when the regenerative braking energy control mode is in a first working condition, the power of the load flow controller, the energy storage system and the port of the single-phase main traction substation is
When the regenerative braking energy control mode is in the second working condition, the power of the load flow controller, the energy storage system and the port of the single-phase main traction substation is
When the regenerative braking energy control mode is in a third working condition, the power of the load flow controller, the energy storage system and the port of the single-phase main traction substation is
In the formula (3), u ε Three-phase voltage unbalance, S, required to be satisfied for power transformation d The short circuit capacity of the power system accessed by the substation is known.
Under the condition of a valley filling charging mode, the power of the ports of the power flow controller, the energy storage system and the single-phase main traction substation is
When the valley filling charging mode is in the second working condition, the power of the ports of the power flow controller, the energy storage system and the single-phase main traction substation is
When the peak clipping discharge mode is in a first working condition, the power of the load flow controller, the energy storage system and the port of the single-phase main traction substation is
When the peak clipping discharge mode is in the second working condition, the power of the power flow controller, the energy storage system and the port of the single-phase main traction substation is
And 5: port power reference value p based on power flow controller and energy storage system obtained in step 4 α_ref 、p β_ref 、p ES_ref Obtaining a port current reference value i of the power flow controller and the energy storage system through a power outer ring α_ref 、i β_ref 、i ES_ref 。
Step 6: and 5, obtaining a current reference value i of the power flow controller and the port of the energy storage system in the step 5 α_ref 、i β_ref 、i ES_ref Actually measured current value i of power flow controller and energy storage system port α 、i β 、i ES A modulation signal is generated via the current inner loop.
And 7: and (4) carrying out PWM modulation on the modulation signal obtained in the step (6) to generate a switching signal for controlling the power flow controller and the energy storage system, carrying out system coordination control, and completing system power transfer under each working condition.
In the specific embodiment of the invention, a certain traction substation in China is taken as an example, and the working effect of the energy storage type traction power supply system is analyzed. The solid line in fig. 5 is the real-time load power of the system, and it can be seen from the graph that the total regenerative braking energy of the traction day is 0.98 ten thousand kW · h, and before the energy storage system is not accessed, the energy is either consumed by the resistor or fed back to the power grid, which not only wastes the energy, but also impacts the three-phase power grid; by adding P ESM After the energy storage type traction system with 5MW is connected to a substation, the available regenerative braking energy per day is increased to 0.82 ten thousand kW.h, so that the utilization rate of the regenerative braking energy is increased to 83.6%, and the part of energy can be used for train traction to save corresponding electricity charge. Assuming that the allowable three-phase unbalance degree of the system is 2%, before the energy storage system is installed, the negative sequence distribution of the traction substation in one day is shown as a dotted line in fig. 6, and it is easy to know from the figure that the three-phase unbalance degree of the traction substation exceeds the standard seriously, and the maximum three-phase unbalance degree reaches about 7% in one day; after the energy storage type traction system is connected into the traction substation, the negative sequence distribution is shown as a solid line in fig. 6, and it can be seen that the three-phase unbalance degree of the substation can be kept below an allowable value of 2% after the energy storage type traction system is connected. Fig. 6 shows that the access of the energy storage type traction system can effectively improve the negative sequence problem of the system and reduce the fine caused by the over-standard of the three-phase unbalance degree of the system. Before the energy storage type traction system is not connected, the demand curve of the traction substation is shown as a dotted line in fig. 7, and the maximum demand of the substation reaches 23 MW; by adding P ESM After the energy storage type traction system with 5MW is connected to the substation, the demand curve of the system is shown by a solid line in fig. 7, and at the moment, the maximum demand of the system is 12.5MW, which is reduced by 10.5MW and saves the corresponding maximum demand electricity charge compared with the situation that the energy storage system is not connected. In a word, the access of the energy storage type traction system can effectively reduce the electricity consumption and the basic electricity charge, can also reduce the fine caused by the negative sequence problem, and has good economic benefit.
Claims (3)
1. A control method of an electrified railway energy storage type traction power supply system comprises the steps that the electrified railway energy storage type traction power supply system comprises a power flow controller (1), an energy storage system (2) and a single-phase main traction transformer (3); the power flow controller (1) comprises a high-voltage matching transformer (4), a power grid side AC-DC converter (6), a traction side AC-DC converter (7), a middle DC side capacitor (8) and a traction matching transformer (5); the primary side of the high-voltage matching transformer (4) is connected to the power grid side, the secondary side of the high-voltage matching transformer is connected to the input end of the power grid side AC-DC converter (6), and the output end of the power grid side AC-DC converter (6) is connected to the input end of the traction side AC-DC converter (7) through a middle DC side capacitor (8) to form a back-to-back structure; the output end of the traction side AC-DC converter (7) is connected to the primary side of a traction matching transformer (5), and the secondary side of the traction matching transformer (5) is connected to the traction side (11); the energy storage system (2) comprises a bidirectional DC/DC converter (9) and an energy storage element (10), wherein the energy storage element (10) is connected in parallel to the middle direct-current side capacitor (8) through the bidirectional DC/DC converter (9); the single-phase main traction transformer (3) is connected to the grid side on the primary side and to the traction side (11) on the secondary side and is connected to the high-voltage matching transformer (4), characterized in that the control method comprises the following steps:
step 1: three-phase unbalance u satisfied by transformer ε For constraint, the working mode of the system is divided into three modes of regenerative braking, peak clipping discharging and valley filling charging according to the magnitude of traction load;
step 2: voltage U of load at outlet of collection substation L And current I L Calculating to obtain the instantaneous power P of the load L ；
And step 3: based on system working mode division principle and load instantaneous power P obtained through calculation L Judging the system operation condition at the moment;
and 4, step 4: based on the system operation condition obtained by judgment, calculating the power reference value p of the ports at the power grid side and the traction side in the power flow controller (1) under the condition α_ref And p β_ref And an energy storage system (2) port power reference p ES_ref ，
And 5: obtaining a power grid side and a traction side in the power flow controller (1) through a power outer ringPort current reference value i α_ref And i β_ref And a reference value i of the port current of the energy storage system (2) ES_ref ；
Step 6: respectively referencing the port current of the power flow controller (1) with a value i α_ref And i β_ref And a reference value i of the port current of the energy storage system (2) ES_ref And the actually measured current values i of the ports at the power grid side and the traction side in the power flow controller (1) α And i β And the current value i of the port of the energy storage system (2) ES Generating a modulation signal through a current inner loop;
and 7: and modulating the obtained modulation signal by PWM to generate a switching signal for controlling the power flow controller (1) and the energy storage system (2), and performing system coordination control to complete system power transfer under each working condition.
2. The control method of the energy-storing traction power supply system of the electrified railway according to claim 1, characterized in that the grid-side AC-DC converter (6) and the traction-side AC-DC converter (7) adopt an H-bridge cascade, MMC or two-level structure.
3. The method for controlling the energy storage type traction power supply system of the electrified railway according to claim 1, wherein the system working mode division principle and the method for determining the port power of the power flow controller and the energy storage system in each working mode comprise:
a: if the load power P L When the energy storage system is smaller than zero, the train works in a regenerative braking state, the system runs in a regenerative braking working mode, and the energy storage system is used for storing and absorbing the regenerative braking energy of the train;
a1) if the train regenerates the braking power | P L |＜P ESM When the system is running in the first working condition of the regenerative braking energy control mode, wherein P is ESM The energy storage system is the preset maximum charge-discharge power of the energy storage system (2); at the moment, all regenerative braking energy is absorbed by the energy storage system (2) through the traction side AC-DC converter (7), and a port power reference value P of the power flow controller (1) is obtained α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a reference value P for the port power of the single-phase main traction transformer (3) T_ref Comprises the following steps:
a2) if the train regenerates the braking power P ESM ＜|P L |＜P ESM +P Low When the system is running, the system is in the second working condition of the regenerative braking energy control mode, wherein P Low Switching threshold value for preset valley filling mode, wherein the threshold value is the unbalance degree u of three-phase voltage required to be met by power transformation ε (%) short circuit capacity S of power system connected with substation d The product of (a); at the moment, the regenerative braking energy passes through the traction side AC-DC converter (7) and is supplied by the energy storage system (2) with the maximum charge-discharge power P ESM Absorbing and returning the residual regenerative braking energy to the three-phase power grid from the single-phase main traction transformer (3) to obtain a port power reference value P of the power flow controller (1) α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a reference value P for the port power of the single-phase main traction transformer (3) T_ref Comprises the following steps:
a3) if the regenerative braking power of the train is | P L |＞P ESM +P Low When the system is in the regenerative braking energy control mode, the system operates in a third working condition; at the moment, the regenerative braking energy passes through the traction side AC-DC converter (7) and is supplied by the energy storage system (2) with the maximum charge-discharge power P ESM Absorbing and returning residual regenerative braking energy to a three-phase power grid from a single-phase main traction transformer (3) and a power grid side AC-DC converter (6), and simultaneously obtaining a port power reference value P of a power flow controller (1) in order to ensure that the negative sequence of the system meets the national standard limit value α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a port power reference value P of the single-phase main traction transformer (3) T_ref Comprises the following steps:
B) if the load power P L If the load is larger than zero, the train works in a traction state, the system runs in a traction working mode, and the energy storage system (2) is used for peak clipping and valley filling of traction load;
b1) if the train pulls the power P L ＜P ESM When the system is operated in a valley filling charging mode, working condition I; at the moment, the traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer, the energy storage system is charged by the three-phase power grid through a traction side AC-DC converter with the same power as the train traction power, and a port power reference value P of the power flow controller (1) is obtained α_ref And P β_ref A port power reference value P of the energy storage system (2) ES_ref And a reference value P for the port power of the single-phase main traction transformer (3) T_ref Comprises the following steps:
b2) if the train pulls the power P ESM ＜P L ＜P Low When the system is in the valley filling charging mode, operating conditions are two; at the moment, the traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer, the energy storage system is charged by the three-phase power grid through a power grid side AC-DC converter with the maximum charging power, and a port power reference value P of the power flow controller (1) is obtained α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a port power reference value P of the single-phase main traction transformer (3) T_ref Comprises the following steps:
b3) if the train pulls the power P Low ＜P L ＜P H In time, the system operates in a peak clipping discharge mode condition one, wherein P H Switching a threshold value for a preset peak clipping mode; at the moment, the energy storage system does not work, the traction power required by the train is provided by a three-phase power grid through a power flow controller and a single-phase main traction transformer, wherein the power flow controller plays a role of peak clipping, and meanwhile, in order to enable the negative sequence of the system to meet the national standard limit value, a port power reference value P of the power flow controller (1) is obtained α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a port power reference value P of the single-phase main traction transformer (3) T_ref Comprises the following steps:
b4) if the train pulls the power P L ＞P H When the system is in the peak clipping discharge mode, operating the system in a second working condition; at this time, the energy storage system has the maximum discharge power P ESM Supplying power to a train, wherein the residual traction power required by the train is provided by a three-phase power grid through a single-phase main traction transformer and a power flow controller, wherein an energy storage system and the power flow controller share the function of peak clipping, and meanwhile, in order to enable the negative sequence of the system to meet the national standard limit value, a port power reference value P of the power flow controller (1) is obtained α_ref And P β_ref Port power reference value P of energy storage system (2) ES_ref And a reference value P for the port power of the single-phase main traction transformer (3) T_ref Comprises the following steps:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910955379.4A CN110829435B (en) | 2019-10-09 | 2019-10-09 | Electrified railway energy storage type traction power supply system and control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910955379.4A CN110829435B (en) | 2019-10-09 | 2019-10-09 | Electrified railway energy storage type traction power supply system and control method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110829435A CN110829435A (en) | 2020-02-21 |
| CN110829435B true CN110829435B (en) | 2022-09-13 |
Family
ID=69548889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910955379.4A Active CN110829435B (en) | 2019-10-09 | 2019-10-09 | Electrified railway energy storage type traction power supply system and control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110829435B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111959350A (en) * | 2020-06-24 | 2020-11-20 | 中铁第一勘察设计院集团有限公司 | Integrated traction power supply system architecture based on source network load storage |
| CN111864774B (en) * | 2020-08-10 | 2022-06-24 | 西南交通大学 | Peak clipping and valley filling control method for in-phase hybrid energy storage power supply structure of electrified railway |
| CN112339620B (en) * | 2020-10-28 | 2022-04-19 | 株洲中车时代电气股份有限公司 | Switching method and system for power supply modes of multi-system train and related components |
| CN112406636B (en) * | 2020-11-04 | 2022-01-28 | 西南交通大学 | Multi-station cooperative regenerative braking energy utilization system and control method thereof |
| CN112994094B (en) * | 2021-03-02 | 2024-01-30 | 中车青岛四方车辆研究所有限公司 | Control method based on alternating current electric energy storage system |
| CN113263920B (en) * | 2021-04-27 | 2022-05-17 | 西南交通大学 | Vehicle-mounted hybrid energy storage system of electrified railway and energy management method thereof |
| CN113381429B (en) * | 2021-06-04 | 2022-05-20 | 西南交通大学 | Flexible power supply device for rail transit and coordination control method |
| CN114498671B (en) * | 2021-12-21 | 2023-03-24 | 西南交通大学 | Flexible traction power supply system and energy coordination control method thereof |
| CN114566988A (en) * | 2022-01-07 | 2022-05-31 | 湘潭大学 | Energy storage access traction power supply system dual-application energy control strategy |
| CN114498706B (en) * | 2022-01-28 | 2023-03-24 | 西南交通大学 | Urban rail hybrid regenerative energy utilization system control method based on power distribution |
| CN114604141B (en) * | 2022-04-07 | 2023-04-25 | 西南交通大学 | Bilateral through in-phase power supply system and control method |
| CN115425672B (en) * | 2022-11-04 | 2023-02-17 | 清华大学 | Dynamic cooperative control method based on approximately optimal flexible direct current traction power supply system |
| CN115622111B (en) * | 2022-11-07 | 2023-05-16 | 清华大学 | Optimal power flow calculation method and device for flexible direct current traction power supply system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101746282A (en) * | 2010-03-12 | 2010-06-23 | 西南交通大学 | Electrified railroad through power supply system without split phase |
| CN102290841A (en) * | 2011-08-13 | 2011-12-21 | 罗俊亚 | Peak clipping and valley filling electric vehicle swapping station for distribution network |
| CN105958521A (en) * | 2016-05-31 | 2016-09-21 | 湖南华大紫光科技股份有限公司 | Unified energy control system |
| CN106159982A (en) * | 2016-07-26 | 2016-11-23 | 湖南华大紫光科技股份有限公司 | Unified energy storage and conversion control system |
| CN107104444A (en) * | 2017-07-05 | 2017-08-29 | 西南交通大学 | A kind of electric railway energy storage cophase supply device and its control method |
| CN107181273A (en) * | 2017-07-05 | 2017-09-19 | 西南交通大学 | A kind of electric railway generating suppling device and its control method |
| CN108336727A (en) * | 2018-01-23 | 2018-07-27 | 西南交通大学 | A kind of new energy supply system and control method for through traction power supply |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE602004032576D1 (en) * | 2004-02-12 | 2011-06-16 | Mitsubishi Electric Corp | POWER CONVERTER |
-
2019
- 2019-10-09 CN CN201910955379.4A patent/CN110829435B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101746282A (en) * | 2010-03-12 | 2010-06-23 | 西南交通大学 | Electrified railroad through power supply system without split phase |
| CN102290841A (en) * | 2011-08-13 | 2011-12-21 | 罗俊亚 | Peak clipping and valley filling electric vehicle swapping station for distribution network |
| CN105958521A (en) * | 2016-05-31 | 2016-09-21 | 湖南华大紫光科技股份有限公司 | Unified energy control system |
| CN106159982A (en) * | 2016-07-26 | 2016-11-23 | 湖南华大紫光科技股份有限公司 | Unified energy storage and conversion control system |
| CN107104444A (en) * | 2017-07-05 | 2017-08-29 | 西南交通大学 | A kind of electric railway energy storage cophase supply device and its control method |
| CN107181273A (en) * | 2017-07-05 | 2017-09-19 | 西南交通大学 | A kind of electric railway generating suppling device and its control method |
| CN108336727A (en) * | 2018-01-23 | 2018-07-27 | 西南交通大学 | A kind of new energy supply system and control method for through traction power supply |
Non-Patent Citations (2)
| Title |
|---|
| Energy Management of Connected Co-Phase Traction Power System Considering HESS and PV;Yuanli Liu et al;《2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)》;20190916;1048-1412 * |
| 电气化铁路电能质量评估及新型控制方案研究;陈民武等;《电力系统保护与控制》;20120816;第40卷(第16期);141-147 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110829435A (en) | 2020-02-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110829435B (en) | Electrified railway energy storage type traction power supply system and control method thereof | |
| CN109572491B (en) | Electrified railway traction network power supply structure and control method thereof | |
| WO2020000843A1 (en) | Optimized energy interconnection system for urban railway train | |
| WO2015014249A1 (en) | New energy-based hybrid bidirectional interactive dc traction power supply system | |
| CN108429276B (en) | High-speed railway energy storage system and control method thereof | |
| CN104527960B (en) | Ship braking energy control system and method | |
| CN111262245A (en) | Energy management optimization operation method for traction power supply system considering photovoltaic uncertainty | |
| Yu et al. | A novel renewable microgrid-enabled metro traction power system—concepts, framework, and operation strategy | |
| CN110071648A (en) | The progress control method of PWM rectifier in a kind of city rail traffic tractive power supply system | |
| CN112009272B (en) | Control method and system for energy storage system of double-flow locomotive | |
| CN115333105B (en) | AC/DC energy storage power supply system and energy control method for electrified railway | |
| CN217087520U (en) | Urban rail transit hybrid regenerative braking energy utilization system | |
| Wang et al. | A layered compensation optimization strategy of energy storage type railway power conditioner | |
| CN113381429B (en) | Flexible power supply device for rail transit and coordination control method | |
| CN219513799U (en) | Electrified railway energy storage type traction power supply system based on energy router | |
| CN109256764A (en) | A kind of vehicle-mounted grid-side converter suitable for middle pressure direct-current traction power supply | |
| Kumar et al. | Investigation on recuperation of regenerative braking energy using ESS in (Urban) rail transit system | |
| Zhou et al. | Research on comprehensive utilization technology of regenerative braking energy for heavy haul railway | |
| CN113178881A (en) | Electrified railway in-phase hybrid energy storage power supply system | |
| CN208257423U (en) | A kind of high-speed railway energy-storage system | |
| CN110994690A (en) | Electrified railway traction power supply system and method based on multi-source access structure | |
| CN115603340A (en) | Electrified railway energy storage type traction power supply system based on MMC and control method | |
| Dai et al. | Analysis and Simulation of Energy Router Suitable for Metro Power Supply Network | |
| CN217215985U (en) | Multi-station comprehensive renewable energy utilization device for heavy haul railway | |
| Cui et al. | Research on Key Technologies of Energy Router for Urban Rail Transit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |