CN109936165A - Diesel Generator System - Google Patents

Abstract

The application proposes a kind of diesel generator system, comprising: diesel generating set, the diesel generating set are connected with ac bus, for providing electric energy to the load being connected with the ac bus；Data detecting unit, the data detecting unit are connected with the ac bus, generate control instruction for acquiring the data of the ac bus in real time, and according to the data of the ac bus；Energy-storage units, the energy-storage units are connected with the data detecting unit, the energy-storage units discharge according to the control instruction, enable the energy-storage units as the backup of the diesel generating set, it discharges when the diesel generating set is abnormal according to the control instruction, it realizes in the case where guaranteeing the load efficiency of diesel generating set, solve the problem of that the diesel engine unit failure under power load fluctuation and individual emergency cases under isolated network mode in diesel engine unit supply network exits paired running.

Description

Diesel Generator System

technical field

The present application relates to the technical field of power generation control, and in particular, to a diesel generator system.

Background technique

At present, Chinese enterprises have mainly placed the new market of the mining industry in the third world, and most of the mining enterprises are located in remote areas. These areas are mostly in areas with no power supply that are difficult to cover by power supply networks or underdeveloped economies. Considering that mining enterprises Due to the large scale of construction and the economy of power supply, enterprises generally use the power supply mode of parallel operation of multiple diesel generator sets under the isolated grid mode.

However, because the power supply network is an isolated network, and the diesel generator is the only power supply, therefore, when the electricity load fluctuates, or when an individual diesel generator suddenly fails to run out of operation, the power supply is Great test of the network. In order to solve such problems and ensure the stability and reliability of power supply, the related technology usually adopts N+M mode of power supply. Multiple diesel generators run in parallel in a way of mutual hot standby. However, such an arrangement makes the operating load rate of the diesel generator set at about 60%, that is, the above problem is solved by sacrificing a load rate of 40%. Therefore, there is an urgent need to propose a method that can not only solve the above problems, but also ensure the load rate of the diesel generator set.

SUMMARY OF THE INVENTION

The present application aims to solve one of the technical problems in the related art at least to a certain extent. Therefore, the first object of the present application is to propose a diesel generator system, so as to solve the power load fluctuation in the power supply network of the diesel generator set in the isolated grid mode under the condition of ensuring the load efficiency of the diesel generator set, and The problem of the failure of diesel units to exit parallel operation in individual emergencies.

In order to achieve the above purpose, an embodiment of the first aspect of the present application proposes a diesel generator system, including: a diesel generator set, the diesel generator set is connected to an AC bus, and used to provide electrical energy to a load connected to the AC bus ; a data detection unit, the data detection unit is connected with the AC bus, used to collect the data of the AC bus in real time, and generate control instructions according to the data of the AC bus; an energy storage unit, the energy storage unit is connected to the The data detection unit is connected, and the energy storage unit discharges according to the control command, so that the energy storage unit can be used as a backup of the diesel generator set, and when the diesel generator set is abnormal, according to the control command to discharge.

Optionally, the energy storage unit includes: a bidirectional converter, the data detection unit is in communication connection with the bidirectional converter, and the bidirectional converter controls the battery assembly to discharge according to the control instruction .

Optionally, the bidirectional converter is further configured to: send the electric energy on the AC bus to the energy storage unit to charge the energy storage unit.

Optionally, the energy storage unit further includes: a transformer, the low voltage side of the transformer is connected to the bidirectional converter, and the high voltage side of the transformer is connected to the AC bus.

Optionally, the diesel generator system further includes: a management unit, the management unit is connected with the diesel generator set and the load, and is used for adjusting the diesel generator set and the load according to the operating parameters of the diesel generator set and the load. Diesel generator set is controlled.

Optionally, the management unit is specifically configured to: identify the abnormality and/or failure of the diesel generator set, control the abnormal and/or faulty diesel generator to be turned off, and control the backup diesel generator to be turned on.

Optionally, the management unit is further configured to: control the diesel generator set to generate electricity according to a preset load rate.

Optionally, the management unit is further connected with the energy storage unit to control the energy storage unit to black start the diesel generator system.

Optionally, the energy storage unit supplies power to the auxiliary equipment of the diesel generator set through the AC bus.

Optionally, the energy storage unit further includes a battery management system, the battery management system is connected between the battery assembly and the bidirectional converter, and the battery management system is configured to charge the battery assembly. Discharge is controlled and protected.

According to the diesel generator system of the embodiment of the present application, the addition of the energy storage unit is simple and easy to implement, which can significantly reduce the power generation cost of the power supply system, reduce the atmospheric pollution and noise pollution to the environment, and provide factories and enterprises with reliable, stable, high-efficiency Quality, low cost power supply.

Additional aspects and advantages of the present application will be set forth, in part, in the following description, and in part will be apparent from the following description, or learned by practice of the present application.

Description of drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily understood from the following description of embodiments taken in conjunction with the accompanying drawings, wherein:

1 is a schematic block diagram of a diesel generator system according to an embodiment of the application;

FIG. 2 is a structural diagram of a diesel generator system according to a specific embodiment of the application.

Detailed ways

The following describes in detail the embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to be used to explain the present application, but should not be construed as a limitation to the present application.

Mineral resources are a kind of non-renewable resources. With the continuous exploitation of domestic mineral resources in China since the reform and opening up, all kinds of minerals are gradually facing the problem of tight supply. Therefore, more and more mining enterprises go abroad to invest overseas to develop minerals. A new direction for the industry.

Chinese enterprises mainly place the new market of the mining industry in the third world countries, and most of the mining enterprises are located in remote areas. Considering the construction scale of the enterprise and the economy of power supply, multiple diesel generator sets in the isolated network mode are usually used in parallel operation. Electric way. In the power supply and distribution system of the diesel generator set in the isolated grid mode, all the power supply comes from the diesel generator set. The large and medium-sized mining enterprises have a large electricity load, and have high requirements on the stability and reliability of the power supply. Therefore, it is impossible to Relying on a single diesel generator to complete the power supply requires multiple diesel generator sets to run in parallel for power supply.

Since the power supply network is an isolated network, the diesel generator is the only power supply, so when the electricity load fluctuates, or the individual diesel engine suddenly fails to run out of operation, it is a major test for the power supply network. In order to solve this problem and ensure the stability and reliability of the power supply, the diesel engine power supply system in this type of isolated grid mode usually adopts the N+M mode to supply power, that is, on the basis of satisfying the conventional power supply capacity, additional configuration 1 One or more diesel generators, and multiple diesel generators operate in parallel in a way of mutual hot standby.

There are many problems in the hot standby power supply system of multiple diesel generator sets in the isolated grid mode:

1) The operating load rate of the diesel unit is low. In order to ensure the reliability and stability of the power supply, to solve the random fluctuation of the load in the isolated grid power supply system, and the individual diesel generators to withdraw from parallel operation due to sudden failures, under normal circumstances, the diesel generator sets operate at about 60% load rate, The other 40% is used as a hot spare capacity to deal with various emergencies.

2) The power generation efficiency of diesel units is low. lead to higher power generation costs. The power generation efficiency of diesel generator sets is related to many factors, but one of the most direct factors is the load rate of the generator set, that is, the higher the operating load rate of the diesel generator set, the higher the corresponding power generation efficiency. However, in order to ensure the reliability of power supply, the diesel power station in the isolated grid mode can only be forced to operate at a low load rate, resulting in a low efficiency of the generator set and an increase in the cost of power generation.

3) The initial investment of diesel power stations is high. Due to the problem of the hot standby capacity of diesel power stations, one or more additional diesel generator sets must be purchased when the diesel power station is initially constructed to meet the normal electricity load, which increases the initial investment cost of the power station. In addition, in order to solve the black start of the power station under the isolated power grid, it is necessary to configure the black start motor, and it is also necessary to increase the initial investment.

4) Diesel units run for a long time, the loss increases and the service life decreases. In order to ensure the reliability of power supply, it is necessary to increase the number of operating units. The operating time of the unit is forced to increase at a lower load rate, resulting in an increase in the relative operating time of a single unit, the loss of the unit itself, and the shortening of the operation and maintenance cycle of the unit. Reduced unit life.

5) The daily operation and maintenance costs are high. There are many diesel generator sets, and the black-start motor must be configured, which will lead to a large workload of daily operation and maintenance of diesel power stations, thereby further increasing the cost of power generation.

6) The power quality of the power supply is poor. Since the reaction speed of diesel generator sets is slower than that of power electronic equipment, the response time of diesel generator sets is longer when the power supply network fluctuates, resulting in poor power supply quality.

7) Environmental pollution. Diesel units will inevitably pollute the atmosphere during operation. The pollution problems are roughly divided into oxidation, acidification, photochemical smog, particulate matter, greenhouse effect and exhaust gas. Diesel generators usually generate noise of 95-125dB(A) when running, and if people live in an environment above 80dB(A) for a long time, it will cause problems such as emotional irritability and hearing loss. Therefore, every additional diesel generator that is turned on increases pollution.

Based on this, the present application proposes a diesel generator system.

The diesel generator system of the embodiment of the present application will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram of a diesel generator system according to an embodiment of the present application. As shown in FIG. 1 and FIG. 2 , the diesel generator system 100 of the embodiment of the present application includes: a diesel generator set 10 , a data detection unit 20 and an energy storage unit 30 .

Wherein, the diesel generator set 10 is connected with the AC bus 40, and is used to provide electrical energy to the load connected with the AC bus; the data detection unit 20 is connected with the AC bus 40, and is used for real-time collection of the data of the AC bus, and according to the data of the AC bus to generate Control command; the energy storage unit 30 is connected to the data detection unit 20, and the energy storage unit 30 can be used as a backup of the diesel generator set, and discharge according to the control command when the diesel generator set is abnormal.

That is to say, when the diesel generator set 10 is working normally, the diesel generator set 10 generates electric energy and supplies the electric energy to the load through the AC bus 40. At this time, the data detection unit 20 detects that the data on the AC bus 40 is normal. When the diesel generator set 10 When a power supply failure occurs, for example, any diesel generator in the diesel generator set 10 fails, so that the power supply cannot meet the load demand, at this time, the data detection unit 20 will detect that the electric energy on the AC bus 40 is lower than the electric energy required by the load. , then a control command is generated and sent to the energy storage unit 30, and the energy storage unit 30 will discharge according to the received control command, so that the energy storage unit acts as a backup of the diesel generator set 10, and when the diesel generator set 10 is abnormal, according to the control command to discharge.

The data detection unit 20 may include a data collector 21 and a data detector 22. The data collector 21 is connected to the AC bus 40 for real-time collection of electrical parameters such as voltage, current, and frequency of the AC bus 40, and real-time data of these parameters. to the data monitor 22. The data monitor 22 reads and records the collected electrical parameters in real time, and compares them with the preset values of the parameters. When the collected parameters do not match the preset values, a control command is generated and transmitted to the energy storage in real time. unit 30. Among them, dedicated high-speed communication is used between the data monitor 22 and the energy storage unit 30 to ensure the reliability and accuracy of the communication, realize millisecond-level response, and ensure the response speed of the energy storage system when the power supply fluctuates.

Therefore, the addition of energy storage units is simple and easy to implement, which can significantly reduce the power generation cost of the power supply system, reduce air pollution and noise pollution to the environment, and provide reliable, stable, high-quality, and low-cost power supplies for factories and enterprises.

Optionally, the energy storage unit 30 includes a bidirectional converter 31 , the data detection unit 20 is connected in communication with the bidirectional converter 31 , and the bidirectional converter 31 controls the battery assembly 32 to discharge according to the control instruction.

It should be noted that the output of the battery assembly 32 in the energy storage unit 30 is direct current, which needs to be converted into alternating current through the bidirectional converter 31 and sent to the AC bus to realize the external power supply of the energy storage unit 30 .

Further, the bidirectional converter 31 is also used for: sending the electric energy on the AC bus 40 to the energy storage unit 30 to charge the energy storage unit.

It should be understood that the bidirectional converter 31 may be a DC/AC bidirectional converter, wherein the DC terminal DC is connected to the battery assembly 32, and the AC terminal AC is connected to the AC bus 40. When the energy storage unit 30 passes through the bidirectional converter When the 31 provides power to the AC bus 40, the bidirectional converter 31 can receive the DC power output by the battery pack 31 through the DC terminal DC, convert the DC power into AC power through inverter, and then provide it to the AC bus 40 through the AC terminal AC, and vice versa .

Furthermore, the energy storage unit 30 further includes a battery management system 33 , the battery management system 30 is connected between the battery assembly 32 and the bidirectional converter 31 , and the battery management system is configured to control and protect the charging and discharging of the battery assembly 32 .

In the embodiment of the present application, compared with various current energy storage batteries, and comprehensively considering the main factors such as product performance and price, a lithium iron phosphate battery is selected as the battery component 32 in the energy storage unit 30 of the present application. Lithium iron phosphate batteries are electrochemical energy storage devices. Each energy storage device consists of a large number of single lithium iron phosphate cells in series and parallel. Therefore, a dedicated battery management system is required to control and protect the charging and discharging of each cell. .

Optionally, the energy storage unit 30 further includes a transformer 34 , the low voltage side of the transformer 34 is connected to the bidirectional converter 31 , and the high voltage side of the transformer 34 is connected to the AC bus 40 .

It should be noted that the transformer 34 is also an electrical device capable of bidirectionally flowing electric energy. The low-voltage alternating current output by the bidirectional converter 31 is boosted by the transformer 34 and then connected to the grid with the high-voltage diesel generator set 10 to form a power supply network for external power supply. The AC bus 40 of the diesel generator set 10 can also step down the high-voltage electricity into low-voltage electricity through the transformer 34 , so as to charge the energy storage unit 30 .

That is to say, in the embodiment of the present application, multiple components in the energy storage unit 30 are connected in the sequence of the battery assembly 32 , the battery management system 33 , the bidirectional converter 31 and the converter 34 , wherein the bidirectional converter 31 It communicates with the data detection unit 20. When the bidirectional converter 31 receives the control signal sent by the data detection unit 20, the bidirectional converter 31 inverts the electric energy stored in the battery assembly 32 to low-voltage alternating current, and then boosts the voltage through the transformer 34. And send it to the AC bus 40 to realize the process of supplying power to the load. When the power of the energy storage unit 30 is insufficient, the transformer 34 can also step down the high-voltage power on the AC bus 40, and then convert it into DC power through the bidirectional converter 31. It is sent to the battery assembly 32 for storage to realize the charging of the energy storage unit 30 .

It should be understood that the aforementioned data monitor 22 can be directly connected to the bidirectional converter 31. When the data monitor 22 detects abnormal data, a control command is generated and sent to the bidirectional converter 31. The data monitor 22 is connected to the bidirectional converter 31. Special high-speed communication is adopted between the current transformers 31 to ensure the reliability and accuracy of the communication, to achieve millisecond-level response, and to ensure the response speed of the energy storage system when the power supply fluctuates.

Optionally, the diesel generator system 100 further includes: a management unit 50, the management unit 50 is connected with the diesel generator set 10 and the load, and is used for controlling the diesel generator set according to the operating parameters of the diesel generator set 10 and the load.

Further, the management unit 50 is specifically used to: identify the abnormality and/or fault of the diesel generator set 10, control the abnormal and/or faulty diesel generator to be turned off, and control the backup diesel generator to turn on; and control the diesel generator set 10 to follow the preset Set the load factor to generate electricity.

Furthermore, the management unit 50 is also connected with the energy storage unit 30 to control the energy storage unit 30 to black start the diesel generator system 100 . The energy storage unit 30 supplies power to the auxiliary equipment of the diesel generator set 10 through the AC bus 40 to realize black start.

Specifically, the management unit 50 communicates with the electrical load, the diesel generator set 10 , the data detection unit 20 , and the energy storage unit 30 in real time, collects electrical parameters of each device, and monitors the running status of the entire diesel generator system 100 in real time. However, the real-time nature of the communication is at the second level. Therefore, the management unit 50 schedules and controls the entire diesel generator system 100 for a relatively long period of time, so as to realize the intelligent optimal control of electric energy dispatching, realize the rational utilization of electric energy at the management level, and reduce the system load. Overall electricity cost.

To sum up, due to its power supply characteristics and requirements for power supply reliability in the isolated grid power supply mode of diesel units, each unit is forced to operate at a lower load rate, resulting in low power supply efficiency and high power supply costs for the entire system. The new intelligent diesel generator system formed after the energy storage unit is added can effectively solve various problems of the original isolated grid power supply system and significantly reduce the power supply cost of the system.

Among them, when the diesel generator system is in normal operation, each diesel generator runs at 80%-90% load rate (which can be determined according to the actual working conditions), the energy storage unit is in a hot standby state, and the data detection unit dynamically monitors the power supply data in real time. When there are small loads in the power supply network that start and stop, and the load fluctuates, the diesel generator set can adjust its output by itself to achieve the dynamic balance of the entire power supply and distribution network.

When a large load starts in the diesel generator system or there is a sudden failure of a single diesel generator, due to the short-term energy imbalance between the supply and distribution, the power quality of the power supply network will be degraded, and the response time of the management unit will be long. , the diesel generator set regulated by the management unit needs a few seconds or even tens of seconds before the original power supply quality can be restored. During the recovery process, the electrical equipment will be affected to varying degrees. In the diesel generator system of the present application The data detection unit detects abnormal fluctuations at the moment when the power quality drops, and immediately generates a control command and sends it to the bidirectional converter. After receiving the control command, the bidirectional converter responds quickly and outputs energy to meet the power supply demand within milliseconds. The decline in power supply quality caused by fluctuations in the power grid can be improved within a short period of time. After a large load is started or a faulty diesel generator supplies power, the energy storage unit exits the power supply and maintains the return to the original power supply mode.

Then, when the diesel generator system is running normally and the electricity load is in the valley time period, the management unit detects the remaining power of the energy storage unit. When the energy storage unit is not full, the diesel generator set not only supplies power to the electricity load At the same time, it also supplies power to the energy storage unit, and charges the energy storage unit through the transformer and bidirectional converter to ensure that the energy storage unit has sufficient power to deal with the situation that the energy storage unit needs to be discharged.

After the entire diesel generator set is powered off and overhauled, the energy storage unit can be used as the black start power supply to first restore the power supply to the auxiliary equipment of the diesel generator set, then complete the startup and parallel operation of the diesel generator set, and finally complete the black start of the entire diesel generator set. Power recovery process.

If an example is used to introduce the technical effect of the power supply system provided by the embodiment of the present application:

Taking an overseas project as an example, the diesel generator set is currently used for power supply, and 8 sets of 8800kw diesel generator sets are configured. During operation, 5 sets are arbitrarily turned on, and the remaining 3 sets are used as backup sets. The power load of the factory is basically maintained between 27000kw-28000kw , the average monthly electricity consumption is about 17.5 million kWh, and the load rate of a single diesel generator is calculated to be about 60%. According to the information provided by the manufacturer, the average load rate of the unit is 60%, corresponding to the average unit efficiency of 39%; the average load rate of the unit is 90%, and the corresponding unit average efficiency is 44%.

Using the diesel generator system proposed in this application, the bidirectional converter is 6500kw, and the lithium iron phosphate battery can store 7500kw, which can increase the load rate from the original 60% to 90%, and the improvement of the unit efficiency brings direct economic cost savings. The economic benefit of saving fuel is about 5 million yuan. In addition, the energy storage unit can also replace the original black start unit, which will also bring many powerful factors such as increased unit life and reduced operation and maintenance costs.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless expressly and specifically defined otherwise.

It should be understood that various parts of this application may be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented by any one of the following techniques known in the art, or a combination thereof: discrete with logic gates for implementing logic functions on data signals Logic circuits, application specific integrated circuits with suitable combinational logic gates, Programmable Gate Arrays (PGA), Field Programmable Gate Arrays (FPGA), etc.

Those skilled in the art can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium, and the program can be stored in a computer-readable storage medium. When executed, one or a combination of the steps of the method embodiment is included.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware, and can also be implemented in the form of software function modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, and the like. Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limitations to the present application. Embodiments are subject to variations, modifications, substitutions and variations.

Claims (10)

1. a diesel generator system, is characterized in that, comprises: a diesel generator set, the diesel generator set is connected to the AC bus, and used to provide electrical energy to the load connected to the AC bus; a data detection unit, the data detection unit is connected to the AC bus, and is used for collecting the data of the AC bus in real time, and generating a control instruction according to the data of the AC bus; An energy storage unit, the energy storage unit is connected to the data detection unit, and the energy storage unit discharges according to the control instruction, so that the energy storage unit can be used as a backup of the diesel generator set, and the energy storage unit can be used as a backup for the diesel generator set. When the generator set is abnormal, it will discharge according to the control command. 2. The diesel generator system according to claim 1, wherein the energy storage unit comprises: A bidirectional converter, the data detection unit is in communication connection with the bidirectional converter, and the bidirectional converter controls the battery assembly to discharge according to the control instruction. 3. The diesel generator system according to claim 2, wherein the bidirectional converter is also used for: The electrical energy on the AC bus is sent to the energy storage unit to charge the energy storage unit. 4. The diesel generator system according to claim 2, wherein the energy storage unit further comprises: A transformer, the low voltage side of the transformer is connected to the bidirectional converter, and the high voltage side of the transformer is connected to the AC bus. 5. The diesel generator system of claim 1, further comprising: and a management unit, which is connected with the diesel generator set and the load, and is used for controlling the diesel generator set according to the operation parameters of the diesel generator set and the load. 6. The diesel generator system according to claim 5, wherein the management unit is specifically used for: An abnormality and/or failure of the diesel generator set is identified, the abnormal and/or faulty diesel generator is controlled to be turned off, and the backup diesel generator is controlled to be turned on. 7. The diesel generator system according to claim 5, wherein the management unit is further used for: The diesel generator set is controlled to generate electricity according to a preset load rate. 8 . The diesel generator system according to claim 5 , wherein the management unit is further connected with the energy storage unit to control the energy storage unit to black start the diesel generator system. 9 . 9 . The diesel generator system according to claim 8 , wherein the energy storage unit supplies power to the auxiliary equipment of the diesel generator set through the AC bus. 10 . 10 . The diesel generator system according to claim 1 , wherein the energy storage unit further comprises a battery management system, and the battery management system is connected between the battery assembly and the bidirectional converter, 10 . The battery management system is configured to control and protect the charging and discharging of the battery assembly.