CN-122026548-A - Switching power supply, control method of switching power supply and power distribution system

CN122026548ACN 122026548 ACN122026548 ACN 122026548ACN-122026548-A

Abstract

The application provides a switching power supply, a control method thereof and a power distribution system. The switching power supply comprises a first power conversion circuit, a second power conversion circuit and a controller, wherein the first power conversion circuit is used for converting electric energy provided by a power grid into first current and outputting the first current to an output bus, the second power conversion circuit is used for converting electric energy provided by an energy accumulator into second current and outputting the second current to the output bus, the controller is coupled with the first power conversion circuit and the second power conversion circuit, and the controller is used for controlling the first current output by the first power conversion circuit and the second current output by the second power conversion circuit according to target current, wherein the target current is expected current for inhibiting power fluctuation of the input bus caused by power fluctuation of a load. The switching power supply can restrain power fluctuation on the power grid side caused by power fluctuation on the load side so as to protect power supply and distribution facilities and improve the utilization rate of electric energy.

Inventors

ZHANG XIJUN
LV DIAN
Lv Qiaoqiang
YANG MENGLIN
XIAO JIAN

Assignees

华为技术有限公司

Dates

Publication Date: 20260512
Application Date: 20241104

Claims (13)

1. A switching power supply, comprising: The first power conversion circuit is coupled with a power grid through an input bus and coupled with a load through an output bus, and is used for converting electric energy provided by the power grid into first current and outputting the first current to the output bus; the second power conversion circuit is coupled with the energy accumulator and the load through the output bus, and is used for converting electric energy provided by the energy accumulator into second current and outputting the second current to the output bus; And a controller coupled to the first power conversion circuit and the second power conversion circuit, the controller being configured to control the first current output by the first power conversion circuit and the second current output by the second power conversion circuit according to a target current, wherein the target current is a desired current for suppressing power fluctuation of the input bus caused by power fluctuation of the load.
2. The switching power supply according to claim 1, wherein the controller is configured to control the first current output by the first power conversion circuit according to a first reference current value, and to control the second current according to a second reference current value, a sum of the first reference current value and the second reference current value being equal to a current value of the target current.
3. The switching power supply of claim 2 wherein the first reference current value is less than or equal to a current value of a maximum rated current of the first power conversion circuit.
4. A switching power supply as claimed in claim 2 or 3, wherein the first power conversion circuit comprises a first power switching tube and the second power conversion circuit comprises a second power switching tube; The controller is used for controlling the current value of the first current to be equal to the first reference current value by adjusting the duty ratio of the first power switch tube, and controlling the current value of the second current to be equal to the second reference current value by adjusting the duty ratio of the second power switch tube.
5. The switching power supply according to claim 4, further comprising a current detection unit for acquiring a detected current value of the first current and a detected current value of the second current and supplying the detected current values to the controller; The controller is used for adjusting the duty ratio of the first power switch tube based on the detected current value of the first current; the controller is used for adjusting the duty ratio of the second power switch tube based on the detected current value of the second current.
6. The switching power supply according to any one of claims 1 to 5, further comprising a voltage detection unit for acquiring a detected voltage of the input bus and supplying the detected voltage to the controller; The controller is used for determining the current value of the target current according to the voltage value of the detection voltage of the input bus and the voltage value of the reference voltage of the input bus.
7. The switching power supply according to claim 6, wherein when a voltage value of the detected voltage of the input bus is less than or equal to a maximum rated voltage value of the first power conversion circuit, The controller is used for controlling the first current to be the target current and controlling the output bus to input current to an energy accumulator coupled with the second power converter through the second power conversion circuit for charging.
8. The switching power supply of any one of claims 1-7 further comprising a power limiting circuit for limiting a maximum power of the input bus to be less than or equal to a sum of a maximum rated power value of the first power conversion circuit and a maximum rated power value of the second power conversion circuit.
9. A power distribution system comprising the switching power supply of any of claims 1-8 for receiving power from a power grid and for providing power to a load.
10. A control method of a switching power supply, characterized by comprising: Obtaining a detection voltage of an input bus through a voltage detection unit, wherein the input bus is used for being coupled with a power grid and a first power conversion circuit, the first power conversion circuit is used for outputting a first current to an output bus, and the first power conversion circuit is coupled to a load through the output bus; Determining a target current, which is a desired current for suppressing power fluctuation of the input bus caused by power fluctuation of the load, based on the detected voltage of the input bus and a reference voltage of the input bus; And respectively controlling a first current output by the first power conversion circuit and a second current output by an energy accumulator through a second power conversion circuit based on the target current, wherein the energy accumulator is used for storing electric energy and is coupled to the output bus through the second power conversion circuit.
11. The control method of a switching power supply according to claim 10, characterized by further comprising, after said determining a target current based on the detected voltage of the input bus and the reference voltage of the input bus: judging whether the energy accumulator is enabled or not: If yes, respectively controlling the first current and the second current based on the target current; if not, controlling the current value of the first current to be equal to the current value of the target current.
12. The method of claim 11, wherein the determining whether the energy storage is enabled comprises: Obtaining a deep filtering voltage value and a shallow filtering voltage value of the input bus through a sampling module, wherein the sampling time average value of the deep filtering voltage value is larger than the sampling average time of the shallow filtering voltage value; Judging whether the energy accumulator is enabled or not based on the deep filtering voltage value or the shallow filtering voltage value: If the shallow filtering voltage value is located outside the expected voltage value range of the input bus, enabling the energy accumulator and outputting the second current through the second power conversion circuit, wherein the expected voltage range of the input bus is a voltage fluctuation range when the power of the input bus is stable; Or alternatively, the first and second heat exchangers may be, And if the deep filtering voltage value is within the expected voltage value range of the input bus and the energy storage voltage of the energy storage device is smaller than the rated voltage of the energy storage device, enabling the energy storage device and receiving the current input by the output bus through the second power conversion circuit for charging.
13. The control method of a switching power supply according to claim 11, wherein the controlling the first current and the second current based on the target current, respectively, includes: Determining a first reference current value and a second reference current value based on the target current, wherein a sum of the first reference current value and the second reference current value is equal to a current value of the target current; judging whether the first reference current value is larger than or equal to the current value of the target current: If yes, controlling the first reference current value to be equal to the current value of the target current, and controlling the output bus to input current to the energy accumulator through the second power conversion circuit for charging; If not, controlling the current value of the first current to be equal to the first reference current value, and controlling the current value of the second current to be equal to the second reference current value.

Description

Switching power supply, control method of switching power supply and power distribution system Technical Field The application relates to the field of power electronics, in particular to a switching power supply, a control method of the switching power supply and a power distribution system. Background Power distribution systems typically carry a switching power supply between the grid and the load, through which an ac or dc voltage on the grid side is converted to an ac or dc voltage required on the load side and distributed to the load for meeting the operating demands on the load side. Wherein the actual power of the load during operation typically exhibits dynamic fluctuations. For example, when power switching occurs on the load side, the current demand on the load side will increase or decrease abruptly, and when the current demand on the load side suddenly changes and is fed back to the grid side, power fluctuation on the grid side will be caused, i.e. the power fluctuation on the load side may cause power fluctuation on the input side of the switching power supply. Fluctuating power can reduce not only the quality of electrical energy, but also the operational performance and life of power supply and distribution facilities. In order to avoid damage caused by overload of power supply and distribution facilities due to power fluctuation, the prior art generally distributes power according to the peak value of power to restrain the power fluctuation. However, the power distribution is performed by the peak value of the power, which results in waste of power supply and distribution infrastructure and power capacity, and maximum utilization of electric energy cannot be achieved. Disclosure of Invention The application provides a switching power supply, which can meet the current demand when the power of a load side fluctuates by synchronously controlling the first current provided by a first power conversion circuit to an output bus and the second current provided by an energy accumulator to the output bus through a second power conversion circuit based on target current, so as to realize the effect of inhibiting the fluctuation of the power of the input bus. The application also provides a control method of the switching power supply and a power distribution system. The application specifically comprises the following technical scheme: In a first aspect, the present application provides a switching power supply, including a first power conversion circuit coupled to a power grid through an input bus and coupled to a load through an output bus, the first power conversion circuit configured to convert electric energy provided by the power grid into a first current and output the first current to the output bus, a second power conversion circuit coupled to an energy storage device and coupled to the load through the output bus, the second power conversion circuit configured to convert electric energy provided by the energy storage device into a second current and output the second current to the output bus, and a controller coupled to the first power conversion circuit and the second power conversion circuit, the controller configured to control the first current output by the first power conversion circuit and the second current output by the second power conversion circuit according to a target current, wherein the target current is a desired current for suppressing power fluctuation of the input bus caused by power fluctuation of the load. The controller of the switching power supply is respectively and electrically connected with the first power conversion circuit and the second power conversion circuit so as to respectively control the first current input to the output bus by the first power conversion circuit and the second current input to the output bus by the second power conversion circuit. The controller controls the first current and the second current based on a target current for suppressing power fluctuation of the input bus caused by load-side power fluctuation, which can be understood as a desired current capable of suppressing power fluctuation of the input bus. The controller synchronously cooperates and controls the first current provided by the first power conversion circuit and the second current provided by the energy accumulator through the second power conversion circuit based on the target current, so that a joint control adjusting effect is formed between the first current and the second current, and the current requirement of the target current when the power of the input bus fluctuates can be met. According to the application, the first current and the second current are controlled based on the target current, namely, the power fluctuation of the input bus caused by the power fluctuation of the load side is restrained by controlling the current, so that the efficiency, the response speed and the accuracy of the switching power supply for restraining the power fluctuation of the