Generator redundant lubricating system based on electric lubricating oil pump and control method

Abstract

The invention relates to a generator redundant lubrication system based on electric lubricating oil pumps and a control method, two electric lubricating oil pumps are connected in parallel to serve as redundant configuration of a generator oil supply system, and are connected with a front bearing and a rear bearing of a generator through flow switches respectively; the control box and the distribution box are connected with the two electric lubricating oil pumps and control the two electric lubricating oil pumps to supply oil for lubrication as required; the control box is connected with the flow switch and used for receiving a lubricating oil flow signal detected by the flow switch and indirectly judging the state of the electric lubricating oil pump according to the lubricating oil flow signal so as to control whether the redundant electric lubricating oil pump is switched into operation or not or send out an interlocking signal to prohibit starting of the diesel generating set. Through redundant configuration of the two electric lubricating oil pumps, the operation reliability of the diesel generating set is improved; through the interlocking arrangement, the diesel generating set cannot be started to operate when the electric lubricating oil pump is not put into operation; and through a power-off protection function, the diesel generating set can be ensured to automatically stop running when power is suddenly cut off.

Description

Technical Field

[0001] The invention relates to a high-power marine diesel generator set, in particular to a lubrication system and a control method for the high-power marine diesel generator set. Background Art

[0002] At present, most marine diesel generator sets mainly use rolling bearings and sliding bearings. The rolling bearing structure is relatively simple and easy to maintain, but it is only suitable for small-power diesel generator sets. For large-power diesel generator sets, most of them use sliding bearings.

[0003] Currently, most diesel generator lubrication is achieved by electric oil pumps. This method has strict safety requirements on the electric oil pump itself and the control strategy. When the electric oil pump fails or the system is powered off, if the diesel generator set cannot be shut down smoothly, the diesel generator set will cause abnormal wear of the generator bearings. Summary of the invention

[0004] The present invention aims to solve the problem of how to ensure that a diesel generator set can still operate stably in the event of an electric lubricating oil pump failure, and to improve the safety of the generator used in the diesel generator set in abnormal situations such as electric lubricating oil pump failure and system power failure by optimizing the control strategy. Furthermore, the present invention proposes a redundant lubrication system and control method for a generator based on an electric lubricating oil pump.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is: a redundant lubrication system for a generator based on an electric lubricating oil pump, comprising a generator lubricating oil box, two electric lubricating oil pumps, a generator, a distribution box, and a control box. The two electric lubricating oil pumps are connected in parallel as a redundant distribution of the generator oil supply system, and are respectively connected to the front and rear bearings of the generator through a flow switch to supply oil to the front and rear bearings of the generator; the control box and the distribution box are connected to the two electric lubricating oil pumps, and the two electric lubricating oil pumps are powered by the distribution box, and the two electric lubricating oil pumps are controlled to supply oil and lubricate respectively; the control box is also connected to the flow switch, which is used to receive the lubricating oil flow signal detected by the flow switch, and output a control signal to the redundant electric lubricating oil pump according to the lubricating oil flow signal, automatically starting the redundant electric lubricating oil pump, thereby ensuring the oil supply to the generator bearing, or sending an interlocking signal to prohibit the diesel generator set from starting.

[0006] Furthermore, the oil suction ports of the two electric lubricating oil pumps are connected to the generator lubricating oil tank via a one-way valve and a coarse filter; the oil delivery port is connected to the front and rear bearings of the generator via a ball valve, a one-way valve, a lubricating oil fine filter, an oil cooler, and a thermostatic valve via two flow switches respectively.

[0007] Furthermore, a lubricating oil heater is also provided in the oil extraction pipeline connecting the one-way valve and the coarse filter.

[0008] Further, the thermostatic valve and oil cooler combination enables the oil temperature to be maintained within a desired range.

[0009] Furthermore, during normal operation, the electric lubricating oil pump extracts the lubricating oil from the generator lubricating oil tank, passes through the coarse filter, ball valve, one-way valve, and lubricating oil fine filter, and then is divided into two paths of lubricating oil and supplied to the front and rear bearings of the generator respectively after passing through the flow switch; the lubricating oil returns to the lubricating oil tank after supplying oil to the front and rear bearings of the generator.

[0010] Furthermore, during normal operation, only one electric lubricating oil pump is used for oil supply and lubrication, and the other electric lubricating oil pump serves as a redundant standby.

[0011] Furthermore, when the current electric lubricating oil pump fails, the flow switch detects that the lubricating oil flow is too low and sends a signal to the control box. After receiving the low flow signal, the control box automatically starts another electric lubricating oil pump to ensure oil supply to the generator bearings.

[0012] Furthermore, when the external AC380V power is cut off, the electric lubricating oil pump stops running, and the diesel generator set is not started, the flow switch detects that the lubricating oil flow is too low and sends a signal to the control box. After receiving the low flow signal, the control box sends an interlock signal to prohibit the diesel generator set from starting;

[0013] Furthermore, when the external AC380V power is cut off, the electric lubricating oil pump stops running, and the diesel generator set is in operation, the control box automatically stops the diesel generator set after detecting the DC24V power failure, thereby protecting the safety of the generator bearing 3.

[0014] A control method for a redundant lubrication system of a generator based on an electric lubricating oil pump, firstly, a standby button is pressed in front of a diesel generator set. If the electric lubricating oil pump starts normally at this time, the vehicle can be prepared smoothly, and the vehicle can be started normally after the preparation is completed; if the electric lubricating oil pump cannot start normally, the vehicle preparation fails, and the diesel generator set enters an interlocking state and is prohibited from starting; when the diesel generator set starts normally, only one of the two electric lubricating oil pumps is put into operation, and the switch is automatically made every 8 hours; if one electric lubricating oil pump fails, the system detects that the lubricating oil flow is low, and the other electric lubricating oil pump is automatically put into operation; when the external AC380V loses power, the diesel generator set control box automatically shuts down to ensure the safety of the generator bearings.

[0015] The beneficial effects of the present invention are:

[0016] (1) The redundant configuration of two electric lubricating oil pre-supply pumps improves the reliability of diesel generator set operation;

[0017] (2) Through the interlock setting, ensure that the diesel generator set will not start and run when the electric lubricating oil pump is not put into operation;

[0018] (3) The power failure protection function ensures that the diesel generator set can automatically stop running when there is a sudden power failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a diagram of a redundant lubrication system for a generator based on an electric lubricating oil pump according to an embodiment of the present invention;

[0020] Figure 2 is a control strategy diagram of a redundant lubrication system for a generator based on an electric lubricating oil pump according to an embodiment of the present invention;

[0021] In the figure: 1. diesel engine, 2. generator, 3. generator bearing, 4. flow switch, 5. thermostatic valve, 6. lubricating oil cooler, 7. lubricating oil fine filter, 8. non-return valve, 9. ball valve, 10. electric lubricating oil pump, 11. oil dipstick, 12. lubricating oil coarse filter, 13. generator lubricating oil tank, 14. distribution box, 15. control box, 16. lubricating oil heater. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0023] Embodiment, a redundant lubrication system for a generator based on an electric lubricating oil pump, such as Figure 1 As shown, the system mainly consists of generator oil tank 13, oil coarse filter 12, check valve 8, electric oil pump 10 (1#, 2#), oil fine filter 7, oil cooler 6, thermostatic valve 5, flow switch 4, generator 2, distribution box 14, control box 15, oil heater 16 and other equipment. It is specifically used in marine diesel generator sets.

[0024] Two electric lubricating oil pumps 10 are connected in parallel as a redundant configuration of redundant pre-supply pumps, and are respectively connected to the front and rear bearings 3 of the generator 2 through the lubricating oil fine filter 7, the lubricating oil cooler 6, the thermostatic valve 5, and the flow switch 4 to supply oil to the front and rear bearings 3 of the generator 2.

[0025] The control box 15 and the distribution box 14 are connected to the two electric lubricating oil pumps 10, and the distribution box 14 provides AC380V electricity to the two electric lubricating oil pumps 10, and controls the two electric lubricating oil pumps 10 to supply oil and lubricate respectively.

[0026] The control box 15 is also connected to the flow switch 4 for receiving the lubricating oil flow signal detected by the flow switch 4 and outputting a control signal to the redundant electric lubricating oil pump 10 or sending an interlocking signal to prohibit the diesel generator set from starting according to the lubricating oil flow signal.

[0027] An oil heater 16 is added to the oil extraction pipeline of the electric oil pump 10 , and an oil dipstick 11 is added to the generator oil tank 13 .

[0028] When all equipments are operating normally, the electric oil pump 10 extracts the oil from the generator oil tank 13, passes through the coarse filter 12, oil heater 16, ball valve 9, check valve 8, oil fine filter 7, and then the oil temperature is kept within a reasonable range by the combination of thermostatic valve 5 and oil cooler 6. The oil is divided into two paths and then supplied to the front and rear bearings 3 of the generator 2 respectively after passing through the flow switch 4. The lubricating oil returns to the oil tank 13 after being supplied to the front and rear bearings of the generator.

[0029] The electric oil pump 10 is provided with AC380V electricity through the distribution box 14 for oil supply and lubrication. During normal operation, only one electric oil pump 10 is needed for oil supply and lubrication, and the other electric oil pump 10 is used as a redundant standby. If the electric oil pump 10 currently supplying oil fails, the flow switch 4 detects that the oil flow is too low and sends a signal to the control box 15. After receiving the low flow signal, the control box 15 automatically starts the other electric oil pump 10, thereby ensuring the oil supply to the generator bearing 3.

[0030] When the external AC380V power is cut off, the electric lubricating oil pump 10 will stop running: 1) If the diesel generator set is not started at this time, the flow switch 4 will detect that the lubricating oil flow is too low and send a signal to the control box 15. After receiving the low flow signal, the control box 15 will send an interlocking signal to prohibit the diesel generator set from starting; 2) If the diesel generator set is in operation at this time, the control box 15 will automatically stop the diesel generator set after detecting that the DC24V power is lost, thereby protecting the safety of the generator bearing 3.

[0031] The specific control method of the redundant lubrication system of the generator based on the electric lubricating oil pump of the present invention is as follows: Figure 2 As shown. Press the standby button before the diesel generator set starts. If the electric lubricating oil pump starts normally, the vehicle can be prepared smoothly. After the preparation is completed, it can be started normally. If the electric lubricating oil pump cannot start normally, the preparation fails, and the diesel generator set enters the interlocking state and is prohibited from starting. After the diesel generator set starts normally, only one of the 1# electric lubricating oil pump and the 2# electric lubricating oil pump is put into operation, and it automatically switches every 8 hours. If the 1# electric lubricating oil pump fails, the system detects that the lubricating oil flow is low, and the other lubricating oil pre-supply pump is automatically put into operation. When the external AC380V loses power, the diesel generator set control box automatically shuts down to ensure the safety of the generator bearings.

Claims

1. A redundant lubrication system for a generator based on an electric lubricating oil pump, characterized in that: It includes a generator oil box, two electric oil pumps, a generator, a distribution box, and a control box. The two electric oil pumps are connected in parallel as a redundant distribution of the generator oil supply system, and are respectively connected to the front and rear bearings of the generator through a flow switch to supply oil to the front and rear bearings of the generator; the control box and the distribution box are connected to the two electric oil pumps, and the two electric oil pumps are powered by the distribution box, and the two electric oil pumps are controlled to supply oil and lubrication respectively; the control box is also connected to the flow switch to receive the oil flow signal detected by the flow switch, and output a control signal to the redundant electric oil pump according to the oil flow signal, automatically starting the redundant electric oil pump, thereby ensuring the oil supply to the generator bearing, or sending an interlocking signal to prohibit the diesel generator set from starting.

2. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 1, characterized in that: The oil suction ports of the two electric lubricating oil pumps are connected to the generator lubricating oil tank via a one-way valve and a coarse filter; the oil delivery port is connected to the front and rear bearings of the generator via a ball valve, a one-way valve, a lubricating oil fine filter, a lubricating oil cooler, and a thermostatic valve via two flow switches respectively.

3. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 2 is characterized in that: A lubricating oil heater is also provided in the oil extraction pipeline connecting the one-way valve and the coarse filter to ensure that the lubricating oil can be preheated when the temperature is low.

4. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 2, characterized in that: The thermostatic valve and oil cooler combination keeps the oil temperature within the required range.

5. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 2, characterized in that: During normal operation, the electric lubricating oil pump draws the lubricating oil from the generator lubricating oil tank, passes through the coarse filter, ball valve, one-way valve, and lubricating oil fine filter, and then is divided into two paths of lubricating oil and supplied to the front and rear bearings of the generator respectively after passing through the flow switch; the lubricating oil returns to the lubricating oil tank after supplying the front and rear bearings of the generator.

6. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 1, characterized in that: During normal operation, only one electric oil pump is used for lubrication, and the other electric oil pump serves as a redundant standby.

7. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 6, characterized in that: When the electric oil pump that supplies oil fails, the flow switch detects that the oil flow is too low and sends a signal to the control box. After receiving the low flow signal, the control box automatically starts another electric oil pump to ensure oil supply to the generator bearings.

8. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 1, characterized in that: When the external AC380V power is off, the electric lubricating oil pump stops running, and the diesel generator set is not started, the flow switch detects that the lubricating oil flow is too low and sends a signal to the control box. After receiving the low flow signal, the control box sends an interlock signal to prohibit the diesel generator set from starting.

9. The redundant lubrication system for generators based on an electric lubricating oil pump according to claim 1, characterized in that: When the external AC380V power is cut off, the electric lubricating oil pump stops running, and the diesel generator set is in operation, the control box automatically stops the diesel generator set after detecting the DC24V power failure, thereby protecting the safety of the generator bearings.

10. A control method for a redundant lubrication system for a generator based on an electric lubricating oil pump according to any one of claims 1 to 9, characterized in that: First, press the standby button before the diesel generator set starts. If the electric lubricating oil pump starts normally, the vehicle can be prepared smoothly. After the preparation is completed, it can be started normally. If the electric lubricating oil pump cannot start normally, the preparation fails, and the diesel generator set enters the interlock state and is prohibited from starting. When the diesel generator set starts normally, only one of the two electric lubricating oil pumps will be put into operation, and the two will be automatically switched every 8 hours. If one electric lubricating oil pump fails, the system will detect that the lubricating oil flow is low and the other electric lubricating oil pump will automatically start running. When the external AC380V power is lost, the diesel generator set control box will automatically shut down to ensure the safety of the generator bearings.

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