Hybrid power unit, hybrid power pumping unit and control method of hybrid power pumping unit

Abstract

The invention belongs to the technical field of engineering equipment, and particularly relates to a hybrid power unit, a hybrid power pumping unit and a control method of the hybrid power pumping unit in order to solve the problems that a fuel engine is high in fuel consumption and difficult to apply in special environments. One path of electric energy generated by the generator can be output through the charging circuit to charge the power battery, and the other path can be provided for the motor through the AC output circuit; the power battery can output electric energy to the motor through the inverter circuit; and the motor is used for driving the operation device. According to the invention, the fuel engine can work in an ideal interval for most time, the occurrence frequency of a fuel consumption peak value is reduced, and the fuel consumption is greatly reduced; the power battery does not need to consume oxygen in an electric driving state, emission is also zero, noise is reduced, stable work in a special environment (such as in a closed or semi-closed space) can be achieved, and environmental applicability is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of engineering equipment, and in particular relates to a hybrid power unit, a hybrid power pumping unit and a hybrid power unit control method. Background Art

[0002] In the petrochemical field, oil transfer generally relies on fuel engine pump units, which convert chemical energy into mechanical energy to drive the oil pump. There are the following defects: 1) Since the oil transfer process requires intermittent work, the fuel engine cannot maintain the best working state under frequent starting, stopping and idling, resulting in increased fuel consumption and high emissions. 2) In addition to high fuel consumption, high oxygen dependence, noise and exhaust emissions will also be generated, which will limit its application in closed and semi-closed spaces. Summary of the invention

[0003] In order to solve the problems of high fuel consumption of fuel engines and difficulty in application in special environments, the present invention provides a hybrid power unit to improve its energy utilization efficiency and environmental adaptability.

[0004] The present invention is achieved through the following technical solutions: a hybrid power unit, which converts the mechanical energy generated by a fuel engine into electrical energy through a generator. The electrical energy generated by the generator can be output to a power battery through a charging circuit on one path, and can be provided to a motor through an AC output circuit on the other path; the power battery can output electrical energy to the motor through an inverter circuit; the motor is used to drive an operating device.

[0005] Furthermore, it also includes a hybrid power controller for controlling the start and stop of the fuel engine according to the working conditions and the power of the power battery.

[0006] Furthermore, it also includes a power battery controller for controlling the charging and discharging process of the power battery.

[0007] Furthermore, it also includes a motor controller for integrating the AC output circuit and the inverter circuit and controlling the on-off of the AC output circuit and the inverter circuit; the output end of the inverter circuit is connected to the input end of the AC output circuit.

[0008] Furthermore, the charging circuit converts the alternating current generated by the generator into direct current through a lithium battery charger to charge the power battery.

[0009] Furthermore, it also includes a stand for integrating and installing various components in the hybrid power unit.

[0010] The present invention further provides a hybrid power pumping unit, comprising the hybrid power unit of the present invention, wherein the operating device is an oil pump or a water pump, and is driven by the motor.

[0011] The present invention also provides a control method for a hybrid power unit, which is used for outputting power of the hybrid power unit of the present invention, and comprises the following steps:

[0012] When the motor is in the starting condition, the inverter circuit is turned on to control the power battery to output electrical energy to the motor;

[0013] When the motor is in operation, determine whether the SOC of the power battery is less than the power threshold;

[0014] If so, the fuel engine is controlled to start, the charging circuit and the AC output circuit are connected, the power battery is charged and the motor is powered through the AC output circuit;

[0015] If not, select the power supply mode according to the working conditions.

[0016] Furthermore, when the SOC of the power battery is less than 20%, the fuel engine is controlled to start, the charging circuit and the AC output circuit are connected, and the power battery is charged while the motor is powered through the AC output circuit;

[0017] When the SOC of the power battery reaches 90%, the charging circuit and the AC output circuit are disconnected, the inverter circuit is connected, and the power battery supplies power to the motor.

[0018] Furthermore, under frequent start-stop conditions, when the SOC of the power battery is greater than or equal to 20%, the fuel engine stops working and the power battery supplies power to the motor;

[0019] Under working conditions requiring high power output, when the SOC of the power battery is greater than or equal to 20%, the fuel engine starts working, and the inverter circuit and the AC output circuit are turned on at the same time, and the power battery and the generator simultaneously power the motor.

[0020] Compared with the prior art, the beneficial effects of the present invention include:

[0021] 1. The present invention uses a fuel engine group composed of a fuel engine and a generator to generate electricity. On the one hand, the electric energy is stored in the power battery, and on the other hand, it can directly drive the motor to do work. The use of a power battery to start the engine avoids frequent starting and stopping of the engine; and the power battery is preferentially used to power the motor. The fuel engine is started only when the motor is in a high-speed power output condition or the power of the power battery is lower than the power threshold. Therefore, the fuel engine works in the ideal range most of the time, reducing the number of peak fuel consumption, greatly reducing fuel consumption, saving energy and reducing emissions.

[0022] 2. When driven in electric mode, the noise will be significantly reduced, no oxygen consumption is required in the short term, and emissions become zero. It can work stably in special environments (such as in closed or semi-closed spaces), improving environmental applicability.

[0023] 3. As long as the fuel engine is started, the power battery can be charged. Compared with pure electric power sources, it can be used without pre-charging and there is no need to worry about insufficient power. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Power flow diagram;

[0025] Figure 2 It is a structural schematic diagram of a bench-type hybrid power pumping unit. DETAILED DESCRIPTION

[0026] The hybrid power unit of the present invention is suitable for working conditions that require frequent starting and stopping, such as water conservancy transfer operations, oil transfer operations, etc. This specific implementation method is described by taking a hybrid power pumping unit for oil transfer operations as an example.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0028] refer to Figure 1 As shown, a hybrid power pumping unit includes a hybrid power unit and an oil pump 5. The hybrid power unit includes a fuel engine unit 1 composed of a fuel engine and a generator. The fuel engine unit 1 converts the mechanical energy generated by the fuel engine into electrical energy through the generator; the electrical energy generated by the generator can be output to the power battery 2 through a charging circuit for charging, and can be provided to the motor 4 through an AC output circuit in another way; the power battery 2 can output electrical energy to the motor 4 through an inverter circuit; and the oil pump 5 is driven by the motor 4.

[0029] refer to Figure 2 In the specific embodiment shown, the charging circuit converts the alternating current generated by the generator 4 into direct current through the lithium battery charger 6 to charge the power battery 2 group.

[0030] In this specific implementation, a power battery controller is also included to control the charging and discharging process of the power battery 2 .

[0031] 1. The specific functions of the power battery controller are as follows

[0032] (1) Power battery information collection

[0033] 1) Voltage: Single cell voltage measurement range 2V~5V

[0034] 2) Current: isolated current transformer, bidirectional detection, range ±30A

[0035] 3) Temperature: Two slave boards, each with 2 temperature measurement points, temperature measurement range: -40~85℃

[0036] (2) Control system

[0037] 1) Single cell balancing control: passive balancing

[0038] 2) Temperature control: Battery pack temperature range: -20~60℃, 2-way switch control

[0039] 3) Protection: single cell disconnection, overvoltage, undervoltage, overcurrent, overtemperature, BMS overtemperature

[0040] refer to Figure 2 As shown, in this specific implementation, a motor controller 3 is also included, which is used to integrate the AC output circuit and the inverter circuit and control the on and off of the AC output circuit and the inverter circuit; the output end of the inverter circuit is connected to the input end of the AC output circuit.

[0041] The relevant parameters and functions of the motor controller are as follows:

[0042] (1) Control range: 72V300A;

[0043] (2) Control power supply voltage: 9VDC~32VDC

[0044] (3) Output frequency range: 0Hz~600Hz

[0045] (4) Torque response time: <200ms

[0046] (5) Torque control accuracy <3%

[0047] (6) Protection functions: overvoltage protection / undervoltage protection / motor overtemperature protection / controller overtemperature protection / short circuit protection / motor overcurrent protection / motor overspeed protection, etc.

[0048] (7) It can realize adaptive adjustment and control of the speed, pressure and flow of the oil pump, and has the functions of displaying oil transfer information, etc.

[0049] refer to Figure 2 As shown, in this specific embodiment, a hybrid power controller 7 is also included, which is used to control the start and stop of the fuel engine according to the working conditions and the power of the power battery 2.

[0050] In this specific implementation mode, reference Figure 2 As shown, it also includes a stand for integrated installation of various components in the hybrid power unit. The stand is built with profiles and equipped with self-locking casters. It is flexible, safe, reliable, strong and durable. All components are integrated and installed in the stand, which can be forked, hoisted and manually transported to meet the requirements of road, rail, water and air transportation.

[0051] In order to minimize the number of engine starts, a control method for a hybrid power unit is provided, which is used to control the output power of the hybrid power unit, and comprises the following steps:

[0052] When the motor 4 is in the starting state, the inverter circuit is turned on to control the power battery 2 to output electric energy to the motor 4;

[0053] When the motor 4 is in operation, it is determined whether the power of the power battery 2 is less than the power threshold;

[0054] If yes, the fuel engine 4 is controlled to start, the charging circuit and the AC output circuit are connected, the power battery 2 is charged and the motor 4 is powered by the AC output circuit;

[0055] If not, the power battery 2 is controlled to output electrical energy to the motor 4 .

[0056] Preferably, when the charging circuit is turned on, the inverter circuit is turned off.

[0057] Preferably, after the power battery is fully charged, the charging circuit is disconnected and the fuel engine continues to work to supply power to the motor until the operation is completed.

[0058] Example 1

[0059] In the generator power-fuel transmission mode, the engine is in working state, driving the generator to generate electricity. The generated electricity charges the battery pack on the one hand, and drives the motor to provide kinetic energy to the oil pump on the other hand, so as to achieve stable operation of the oil pump. In the generator power-fuel transmission mode, as long as the fuel engine has sufficient fuel, the fuel supply work can be carried out continuously.

[0060] Example 2

[0061] The battery power drives the fuel transfer, the engine is always in a stopped state, and the motor works with the power stored in the battery pack. In this mode, no oxygen is consumed and no exhaust gas is generated. The noise and heat radiation are low, so this working state has strong environmental compatibility. After the power battery is exhausted, it is necessary to start the engine to transfer fuel in the generator power fuel transfer mode and charge the battery pack at the same time.

[0062] Example 3

[0063] Under frequent start-stop conditions, when the SOC of the power battery is greater than or equal to 20%, the fuel engine stops working and the power battery supplies power to the motor;

[0064] The power supply of the power battery will cause the power to decrease. When the SOC of the power battery is less than 20%, the fuel engine is controlled to start, and the charging circuit and the AC output circuit are connected to charge the power battery while supplying power to the motor through the AC output circuit. During the charging process, when the SOC of the power battery reaches 90%, the charging circuit and the AC output circuit are disconnected, and the inverter circuit is connected to supply power to the motor from the power battery.

[0065] This can ensure the performance of the hybrid system while reducing overcharging and over-discharging, extending the service life of the lithium-ion battery.

[0066] Example 4

[0067] Under working conditions requiring high power output, when the SOC of the power battery is greater than or equal to 20%, the fuel engine starts working, and the inverter circuit and the AC output circuit are turned on at the same time, and the power battery and the generator simultaneously power the motor.

[0068] The power supply of the power battery will cause the power to decrease. When the SOC of the power battery is less than 20%, the fuel engine is controlled to start, and the charging circuit and the AC output circuit are connected to charge the power battery while supplying power to the motor through the AC output circuit. During the charging process, when the SOC of the power battery reaches 90%, the charging circuit and the AC output circuit are disconnected, and the inverter circuit is connected to supply power to the motor from the power battery.

[0069] This can ensure the performance of the hybrid system while reducing overcharging and over-discharging, extending the service life of the lithium-ion battery.

[0070] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0071] The above technical solution is only one implementation mode of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the principles disclosed in the present invention, and it is not limited to the technical solution described in the above specific embodiments of the present invention. Therefore, the above description is only preferred and does not have a restrictive meaning.

Claims

1. A hybrid power unit, characterized in that: The mechanical energy generated by the fuel engine is converted into electrical energy through a generator. The electrical energy generated by the generator can be output to the power battery through a charging circuit on one path and can be provided to the motor through an AC output circuit on the other path; the power battery can output electrical energy to the motor through an inverter circuit; the motor is used to drive the working device.

2. The hybrid power unit according to claim 1, characterized in that: It also includes a hybrid power controller, which is used to control the start and stop of the fuel engine according to the operating conditions and the power battery level.

3. The hybrid power unit according to claim 2, characterized in that: It also includes a power battery controller for controlling the charging and discharging process of the power battery.

4. The hybrid power unit according to claim 3, characterized in that: It also includes a motor controller for integrating the AC output circuit and the inverter circuit and controlling the on-off of the AC output circuit and the inverter circuit; the output end of the inverter circuit is connected to the input end of the AC output circuit.

5. The hybrid power unit according to claim 4, characterized in that: The charging circuit converts the alternating current generated by the generator into direct current through a lithium battery charger to charge the power battery.

6. The hybrid power unit according to claim 5, characterized in that: It also includes a stand for integrated installation of various components in the hybrid power unit.

7. A hybrid power pumping unit, characterized in that: It comprises a hybrid power unit as claimed in any one of claims 1 to 6, wherein the operating device is an oil pump or a water pump, and is driven by the motor.

8. A control method for a hybrid power unit, characterized in that: The method for controlling the output power of the hybrid power unit as claimed in claim 1 comprises the following steps: When the motor is in the starting condition, the inverter circuit is turned on to control the power battery to output electrical energy to the motor; When the motor is in operation, determine whether the SOC of the power battery is less than the power threshold; If so, the fuel engine is controlled to start, the charging circuit and the AC output circuit are connected, the power battery is charged and the motor is powered through the AC output circuit; If not, select the power supply mode according to the working conditions.

9. The control method of the hybrid power unit according to claim 8, characterized in that: When the SOC of the power battery is less than 20%, the fuel engine is controlled to start, the charging circuit and the AC output circuit are connected, and the power battery is charged while the motor is powered through the AC output circuit; When the SOC of the power battery reaches 90%, the charging circuit and the AC output circuit are disconnected, the inverter circuit is connected, and the power battery supplies power to the motor.

10. The control method of the hybrid power unit according to claim 8, characterized in that: Under frequent start-stop conditions, when the SOC of the power battery is greater than or equal to 20%, the fuel engine stops working and the power battery supplies power to the motor; Under working conditions requiring high power output, when the SOC of the power battery is greater than or equal to 20%, the fuel engine starts working, and the inverter circuit and the AC output circuit are turned on at the same time, and the power battery and the generator simultaneously power the motor.

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