WO2022262258A1

WO2022262258A1 - Power supply unit, power supply apparatus, and power supply system

Info

Publication number: WO2022262258A1
Application number: PCT/CN2021/143882
Authority: WO
Inventors: 踪成林; 张凯旋; 张海东; 付加友; 陈小平; 李晨光; 朱建国
Original assignee: 深圳市永联科技股份有限公司
Priority date: 2021-06-15
Filing date: 2021-12-31
Publication date: 2022-12-22
Also published as: CN113258753B; CN113258753A

Abstract

Provided in the present invention are a power supply unit, a power supply apparatus, and a power supply system. The power supply unit is a first power supply unit in a power supply apparatus, wherein the first power supply unit is used for: when the required current value of a load is greater than an output current limit value of the first power supply unit, acquiring an actual output voltage of each power supply unit in the power supply apparatus; determining an output voltage average value according to the actual output voltage of each power supply unit; and sending the output voltage average value to each second power supply unit, wherein the output voltage average value is used by each second power supply unit to perform the following operations: determining an output voltage set value of the second power supply unit according to the output voltage average value, wherein each second power supply unit has the same output voltage set value, which is determined according to the output voltage average value. The power supply unit provided in the present invention is applied to a power supply apparatus with serial outputs, which is beneficial to maintaining the equalization of the output power of different power supply units in the power supply apparatus, thereby prolonging the service life of the power supply units and the entire power supply apparatus, and improving the reliability of the power supply apparatus.

Description

A power supply unit, a power supply device and a power supply system

This application claims the priority of the Chinese patent application with the application number 2021106581130 and the title of "a power supply unit, power supply device and power supply system" submitted to the China Patent Office on June 15, 2021, the entire contents of which are incorporated by reference in In this application.

technical field

The invention belongs to the field of power supply technology, and in particular relates to a power supply unit, a power supply device and a power supply system.

Background technique

With the development of the energy industry, the user's demand for the output voltage range of the power supply is becoming wider and wider. When the output voltage demand exceeds 2000V, it is difficult for conventional semiconductor components to meet the voltage stress requirements, and device-level series connection is required. Device-level It is difficult to design in series, so at present, the output of the power supply is usually connected in series to increase the output voltage range of the power supply. In a multi-power supply output series system, when the actual load demand is greater than the output current limit of some power supplies in the system, the whole system will have the problem of unbalanced output power among different power supplies. If the whole system is in a state of unbalanced output power for a long time, This will result in a shortened service life of the entire system.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide a power supply unit, a power supply device, and a power supply system, in order to realize the output power balance of each power supply unit in the scenario where the output of the power supply unit is connected in series, which is beneficial to improve the power supply unit. service life and reliability.

In order to achieve the above object, the present invention provides a power supply unit, the power supply unit is the first power supply unit in the power supply device, the power supply device includes the first power supply unit and at least one second power supply unit, the first power supply unit The output port of the power supply unit and the output port of each second power supply unit are connected in series to the load, any two power supply units in the power supply unit are connected through a communication bus, and the first power supply unit is the output current of the power supply unit. The power supply unit with the smallest limit value;

The first power supply unit is used to obtain the actual output voltage of each power supply unit in the power supply device when the load demand current value is higher than the output current limit value of the first power supply unit; according to each power supply unit The actual output voltage of the actual output voltage, determine the average value of the output voltage; send the average value of the output voltage to each of the second power supply units, the average value of the output voltage is used for each of the second power supply units to perform the following operations: according to the The output voltage average value determines the output voltage setting value of the second power supply unit, and the output voltage setting values determined by each second power supply unit according to the output voltage average value are the same.

Further, in terms of sending the average value of the output voltage to each of the second power supply units, the first power supply unit is specifically configured to: compare the actual output voltage of the first power supply unit with the system setting voltage value When the difference is greater than the preset difference, the average output voltage is sent to each of the second power supply units, and the system set voltage value is not higher than the load demand current value of the first power supply unit When the output current is limited, the output voltage setting value of each power supply unit in the power supply device.

Further, the average output voltage is specifically used for each of the second power supply units to perform the following operation: determine the smaller voltage value of the average output voltage and the system setting voltage value as the second power supply unit When the output voltage setting value of the load demand current is not higher than the output current limit value of the first power supply unit, the output voltage setting value of each power supply unit in the power supply unit is the system setting voltage value.

Further, the output current limit values of any two different power supply units in the power supply device are different.

Further, the output current limit of the third power supply unit in the power supply device is determined according to the preset first current limit value, the first parameter value corresponding to the third power supply unit and the preset current limit adjustment parameter, The greater the first parameter value corresponding to the third power supply unit, the greater the difference between the output current limit value of the third power supply unit and the first current limit value;

Wherein, the difference is proportional to the preset current limit adjustment parameter, the third power supply unit is any power supply unit in the power supply device, and each power supply unit in the power supply device corresponds to a first parameter value, the first parameter values corresponding to any two different power supply units are different, and the first parameter value corresponding to the first power supply unit is the smallest.

Further, the output current limit of the third power supply unit=the first current limit value+the first parameter value corresponding to the third power supply unit×the current limit adjustment parameter, and the current limit adjustment parameter is based on The preset rated current value and the preset steady current accuracy value are determined.

Further, the current limit adjustment parameter=(2÷preset parameter difference)×the preset steady current accuracy value×the preset rated current value, wherein, according to each power supply unit in the power supply device The corresponding first parameter values are from small to large or from large to small. When sorting the power supply units, the difference between the first parameter values corresponding to any two adjacent power supply units is the preset parameter difference.

Further, any power supply unit in the power supply device includes:

Control module, power module, diode module and capacitor module;

The control module is connected to the control port of the power supply module, and the control module communicates with other power supply units through a communication bus. The input terminal of the power supply module is used to connect to an external power supply. The negative pole of the diode module and the first end of the capacitor module are combined and then connected to the positive output port of the power supply unit. The negative output terminal of the power supply module is connected to the positive pole of the diode module and the second terminal of the capacitor module. After the terminal is combined, it is connected to the negative output port of the power supply unit;

The control module of the first power supply unit is used to realize the functions realized by the first power supply unit as described in the first aspect;

The power supply module of the first power supply unit is used to output an electrical signal for charging the load according to the output voltage setting value of the first power supply unit; the capacitor module of the first power supply unit is used to output the electric signal to the power supply module The electric signal of the first power supply unit is filtered; the diode module of the first power supply unit is used to prevent the output of the other power supply units from affecting the capacitor module of the first power supply unit.

The present invention also provides a power supply device, which includes the power supply unit according to the first aspect, the power supply unit is a first power supply unit, at least one second power supply unit, the output port of the first power supply unit and The output port of each second power supply unit is connected to the load in series, any two power supply units in the power supply unit are connected through a communication bus, and the first power supply unit is the power supply unit with the smallest output current limit in the power supply unit .

The present invention also provides a power supply system, comprising the power supply unit according to the first aspect or the power supply device according to the second aspect.

Beneficial effects of the present invention:

Compared with the prior art, the present invention provides a power supply unit, a power supply device and a power supply system, the power supply device includes a first power supply unit and at least one second power supply unit, the output port of the first power supply unit and each second power supply unit The output ports are connected in series to the load. The power supply unit with the smallest output current limit in the power supply unit is the first power supply unit. When the load demand current value is higher than the output current limit of the first power supply unit, the first power supply unit will voltage, determine the average value of the output voltage, and send it to each second power supply unit, so that each second power supply unit can determine the same output voltage setting value according to the output voltage value. That is, when the whole power supply device enters the state of unbalanced output power between different power supply units, the first power supply unit determines the average output voltage according to the actual output voltage of each power supply unit, and sends it to each second power supply unit for adjusting the output voltage of each second power supply unit. The output voltage setting value of the two power supply units, and the output voltage setting value of each second power supply unit is the same value, because the current in the series circuit is the same, the output power between different power supply units of the power supply device can be gradually adjusted to be relatively balanced state. It can be seen that the power supply unit provided by the present invention is applied in a power supply unit with series output, which is conducive to maintaining the output power balance of different power supply units in the power supply unit, improving the service life of each power supply unit and the entire power supply unit and the reliability of the power supply unit.

Description of drawings

The present invention is further described by using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, without paying creative work, other embodiments can also be obtained according to the following accompanying drawings Attached picture.

Fig. 1 is a schematic diagram of a circuit principle of a power supply unit provided by the present invention;

Fig. 2 is a schematic diagram of the circuit principle of another power supply unit provided by the present invention;

Fig. 3 is a schematic diagram of the circuit principle of another power supply unit provided by the present invention.

detailed description

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance. As used in the embodiments of the present invention and the appended claims, the singular forms "a", "said" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

At present, in a system in which multiple power supplies are output in series, when the actual load demand is less than the current limit value of each power supply in the system, all power supplies work in a voltage loop, that is, all power supplies output the same voltage set by the system. Since the output of the power supply is used in series, the output current of all the power supplies in the series circuit is exactly the same, so when the voltage loop works, the output power of all the power supplies is relatively balanced.

When the actual load demand is greater than the current limit value of some power supplies in the system, the power supplies whose current limit value is lower than the load demand will enter the current loop to work in sequence according to their own current limit value, and other power supplies with a current limit value higher than the load demand work at the voltage ring. Specifically, the power supply with the smallest current limit value will enter the current loop first, and control its own output current not to exceed its own current limit value. Since the output current of the entire series system is limited by the current limit value of the power supply working in the current loop, then The total output voltage of the entire system will be pulled down, the power supply working in the voltage loop will still output according to the set voltage value, and the output voltage of the power supply working in the current loop will be pulled down uncontrolled, lower than the set voltage value, When the output voltage of the power supply drops to 0 or even reverses under the influence of the output of other power supplies, other power supplies enter the current loop in turn according to their own current limit values.

That is to say, in the whole series system, some power supplies whose current limit value is lower than the load demand all work in the current loop, and other power supplies work in the voltage loop. The output voltage of the power supply working in the current loop is lower than that of the power supply working in the voltage loop. The system is in a state of unbalanced power. If the entire system is in a state of unbalanced power for a long time, it will affect the service life and reliability of the entire system and internal power supply.

In view of the above problems, the present invention provides a power supply unit, a power supply device and a power supply system, which will be described in detail below with reference to the accompanying drawings.

Example 1:

Referring to Fig. 1, this embodiment provides a power supply unit, the power supply unit is the first power supply unit in the power supply device, the power supply device includes the first power supply unit and at least one second power supply unit, the first power supply unit The output port of a power supply unit and the output port of each second power supply unit are connected in series to the load, any two power supply units in the power supply unit are connected through a communication bus, and the first power supply unit is the output port of the power supply unit. Power supply unit with minimum current limit;

Specifically, Fig. 1 shows the connection mode of the output terminals of each power supply unit in the power supply device. Outside the unit, the positive output port of each power supply unit is connected to the negative output port of an adjacent power supply unit, and the negative output port of each power supply unit is connected to the positive output port of the other adjacent power supply unit. Among the power supply units, the positive output port of the power supply unit that is not connected to the negative output port of other power supply units is connected to the positive output port of the power supply unit, and the negative output port of the power supply unit that is not connected to the positive output ports of other power supply units is connected to the negative output port of the power supply unit. port. For example, in FIG. 1, the positive output port Vo1+ of the first power supply unit is connected to the positive output port Vout+ of the power supply device, and the negative output port Vo2- of the second power supply unit is connected to the negative output port Vout- of the power supply device.

In a specific implementation, when the power supply device is applied in a vehicle power supply system, the communication bus may be a Controller Area Network (CAN) bus, that is, every two power supply units may be connected through CAN bus communication.

In the specific implementation, considering that the load demand current exceeds the output current limit value of some power supply units (the first part of the power supply unit described later) in the power supply device, the actual output voltage of the first part of the power supply unit will be pulled down first, and the power supply device will be lowered under the current load. The actual total output voltage is lower than the originally set total output voltage. That is, the actual output voltage of each power supply unit in the first part of the power supply unit is lower than the average value of the originally set total output voltage. At this time, if the output voltage value of the first part of the power supply unit is not set, and the second part of the power The other power supply units in the device except the first part of the power supply unit) still control the output according to the average value of the originally set total output voltage, then the actual output voltage of the first part of the power supply unit will always be lower than the actual output voltage of the second part of the power supply unit , the entire power supply device has been in a power unbalanced state.

Therefore, when the load demand current is higher than the output current limit of the first power supply unit, that is, when the output power of different power supply units in the power supply device is unbalanced, the first power supply unit can determine according to the actual output voltage of each power supply unit. The average value of the output voltage is sent to each second power supply unit for determining the set value of the output voltage. In specific implementation, each second power supply unit can determine the average output voltage as the output voltage setting value of the unit, that is, each second power supply unit controls the output voltage of the unit according to the average output voltage.

Specifically, the actual output voltage of each power supply unit may be the sampled value of the output voltage of the power supply unit. The first power supply unit can receive the output voltage sample value from each second power supply unit through the communication bus. Specifically, each second power supply unit can send the output voltage sampling value of this unit to the first power supply unit in real time (can be set every preset time), and at the same time, the first power supply unit can also collect the output voltage of this unit in real time sample value. That is, the first power supply unit continuously obtains the actual output voltage of each power supply unit, and determines the average value of the output voltage, and then continuously adjusts the set value of the output voltage of each second power supply unit according to the average value of the output voltage.

Since each second power supply unit controls the output voltage of the unit according to the average value of output voltage (the voltage value obtained by dividing the actual total output voltage by the number of power supply units), the actual output voltage of the first power supply unit will naturally gradually change to the same value as In the equal state of each second power supply unit, since the output current of each power supply unit in the series circuit is naturally equal, and the actual output voltage of each power supply unit is adjusted to the average value of the output voltage, the output power of each power supply unit in the entire power supply device Basic balance.

In addition, in a specific implementation, the first power supply unit is also used to control the output current of the unit not to exceed the output current limit of the unit. That is, in the end, each second power supply unit in the power supply device works in the voltage loop, the voltage setting value is the average value of the output voltage, the first power supply unit works in the current loop, and the current in the entire output series circuit is controlled not to exceed the output of the first power supply unit current limit.

In specific implementation, the average value of the output voltage can be determined by the following formula:

Vmain_set=Vo_samp÷N;

Wherein, Vmain_set is the average value of the output voltage, Vo_samp is the sum of actual output voltages of each power supply unit in the power supply device, and N is the number of power supply units in the power supply device. The first power supply unit can communicate with other power supply units in the system through the communication bus, so as to determine the number of power supply units in the power supply device.

In addition, in practical applications, the first power supply unit can be set to obtain its own actual output voltage in real time as long as it is powered on, and the second power supply unit can be set to keep sending its own voltage to the first power supply unit in real time as long as it is powered on. The actual output voltage, or, in order to reduce unnecessary data transmission, the first power supply unit can be set to send the actual output to each second power supply unit when the load demand current is greater than the output current limit of this unit Voltage acquisition request, the first power supply unit can also be set to send its output voltage sampling value to the second power supply unit in real time when receiving the actual output voltage acquisition request from the first power supply unit, which is not specifically limited here .

In this embodiment, in terms of sending the average value of the output voltage to each of the second power supply units, the first power supply unit is specifically configured to: compare the actual output voltage of the first power supply unit with the system setting voltage When the difference between the values is greater than the preset difference, the average value of the output voltage is sent to each of the second power supply units, and when the load demand current is not higher than the output current limit of the first power supply unit, the The output voltage setting value of each power supply unit in the power supply unit is the system setting voltage value.

In specific implementation, when the first power supply unit does not send the average output voltage to the second power supply unit, that is, when the load demand current does not exceed the output current limit of the first power supply unit, the first power supply unit and the second power supply unit follow the The originally set output voltage (that is, the system setting voltage value) controls the output, and when the first power supply unit sends the average value of the output voltage to the second power supply unit, the second power supply unit will re-determine the output voltage setting value according to the output voltage value, The output voltage of the first power supply unit also changes as the output voltage of the second power supply unit changes.

Among them, when the load demand current of the first power supply unit is greater than the output current limit of the unit, the output voltage will drop, and the total output voltage will drop, then the average value of the output voltage will be lower than the system setting voltage value, and the second power supply unit will When the output voltage is adjusted, the output voltage of the first power supply unit will rise again. In order to avoid that the difference between the load demand current and the output current limit of the first power supply unit is very small, that is, the actual output voltage of the first power supply unit fluctuates around the system setting voltage value (that is, the actual output voltage of the first power supply unit The difference of the set voltage value is very small), which leads to repeatedly adjusting the output voltage set value of the second power supply unit according to different strategies. Each second power supply unit sends the average value of the output voltage, which is beneficial to avoid repeated regulation and fluctuation of the output voltage of each power supply unit.

For example, if V1 is the actual output voltage of the first power supply unit, Vset is the system setting voltage value, and ΔV is the preset difference value, then the first power supply unit will only send to the second power supply unit when V1<Vset-ΔV average output voltage.

In this embodiment, the average value of the output voltage is specifically used for each of the second power supply units to perform the following operation: determine the smaller voltage value of the average value of the output voltage and the system setting voltage value as the second The output voltage setting value of the second power supply unit, when the load demand current is not higher than the output current limit value of the first power supply unit, the output voltage setting value of each power supply unit in the power supply unit is the system setting voltage value.

In a specific implementation, the power supply device may include a monitoring unit, which is connected to each power supply unit through a communication bus, and is used to send a system setting voltage value to each power supply unit. The system setting voltage value may be the load value determined by the monitoring unit. The required voltage value; or in the case that there is no monitoring unit in the power supply device, the system set voltage value can be a preset fixed value, which is pre-stored in each power supply unit.

Specifically, the monitoring system can directly send the total output voltage setting value Vtotal or the system setting voltage value Vset of a single power supply unit to each power supply unit. If the monitoring system sends Vtotal to each power supply unit, each power supply unit is on After power-on, communicate with other power supply units to determine the number N of power supply units, and obtain the system setting voltage value Vset according to Vtotal÷N. Similarly, Vtotal can also be pre-stored in each power supply unit, and each power supply unit can determine Vset according to the number of power supply units in the power supply device, or Vset can be directly pre-stored in each power supply unit.

In specific implementation, if the system setting voltage value is higher than the average output voltage, that is, the actual output voltage of some power supply units in the power supply device is lower than the system setting voltage, that is, the actual output voltage of some power supply units is lower than the other power supply The actual output voltage of the unit, at this time, in order to avoid the unbalanced output voltage of each power supply unit, the output voltage setting value of each second power supply unit is the average value of output voltage (determined according to the actual output voltage of each power supply unit average value), then the output voltage of the first power supply unit can also be adjusted to be balanced with the output voltage of each second power supply unit.

If the system set voltage value itself is lower than the average value of the output voltage, that is, the actual total output voltage of the power supply device is higher than the total set voltage corresponding to the system set voltage value. Since the system set voltage value is the load demand voltage set by the monitoring unit, or the preset output voltage of each power supply unit, when the actual output voltage value is higher than the preset total set voltage, each second power supply unit will When the system setting voltage value is determined as the output voltage setting value of the unit, the output voltage of the first power supply unit will also be naturally adjusted to the system setting voltage to achieve output voltage balance.

In this embodiment, the output current limit values of any two different power supply units in the power supply device are different.

In the specific implementation, it is considered that in the case of a sudden increase of the deep current-limited load, that is, when the load demand current suddenly becomes much larger, because the load change is instantaneous, the first power supply unit cannot immediately supply power to each second power supply unit The average value of the output voltage is sent, that is, the power supply units in the entire power supply device cannot be adjusted to a relatively balanced output power state immediately. At the moment when the load changes, the output voltage of the power supply unit whose output current limit is lower than the load demand current in the power supply device will suddenly drop (that is, enter the current loop to control the output current of the unit not to exceed the output current limit of the unit), and then Under the adjustment of the average value of the output voltage, the output power is relatively balanced (that is, except for the first power supply unit, the power supply units whose output current limit is less than the load demand current all exit the current loop, and each second power supply unit works in the voltage loop. , the same output voltage setting value is determined according to the average value of the output voltage from the first power supply unit).

Therefore, the output current limit of each power supply unit is set to a different value, that is, the output current limit of the entire power supply unit is set in sections. The power supply units whose current limit value is lower than the load demand current will be lowered in turn. It is beneficial to avoid that when the current limiting values of multiple power supply units are the same and are all lower than the load demand current, the voltages of multiple power supply units in the power supply unit drop at the same time, resulting in a large change in the output state of the entire power supply unit and thus oscillation.

In this embodiment, the output current limit value of the third power supply unit in the power supply device is adjusted according to the preset first current limit value, the first parameter value corresponding to the third power supply unit and the preset current limit value Parameter determination, the greater the first parameter value corresponding to the third power supply unit, the greater the difference between the output current limit value of the third power supply unit and the first current limit value;

In specific implementation, if the power supply device includes a monitoring unit, each power supply unit can receive the first current limiting value from the monitoring unit; or, the first current limiting value can also be pre-stored in each power supply unit, and each power supply unit The output current limit of the unit can be determined according to the first current limit value. Specifically, each power supply unit can adjust parameters according to the first parameter value corresponding to the unit and the preset current limit value to determine the difference between the output current limit value of the unit and the first current limit value. The larger the difference is, the first parameter value corresponding to the first power supply unit is the smallest, and the output current limit of the first power supply unit is the smallest. That is to say, the larger the difference determined by the power supply unit, the power supply unit The larger the output current limit, that is, the larger the first parameter value corresponding to the power supply unit, the larger the output current limit of the power supply unit.

It is beneficial to ensure that when the load demand is greater than the output current limit of some power supply units, the output voltage of the power supply unit whose output current limit is smaller than the load demand current will decrease in order according to the order of the first parameter value from small to large, and then in the first power supply unit. Under the adjustment of the average value of the output voltage, the output voltage rises sequentially according to the order of the first parameter value from large to small, and finally the output voltage of each power supply unit is maintained in a relatively balanced state.

In specific implementation, for the sake of convenience, the first parameter value can be the address of each power supply unit. Since the address of each power supply unit is different, there is no need to set an additional associated parameter value for each power supply unit as The first parameter value.

For example, if the power supply device includes N power supply units, the addresses of the N power supply units can be N integers ranging from 0 to (N−1), wherein the power supply unit with the address of 0 is the first power supply unit. When a deep current-limited load is suddenly added, the power supply unit with address 0, that is, the first power supply unit, enters the current loop (that is, controls the output current of this unit not to exceed the output current limit of this unit, so that the output voltage of this unit drops), and The output voltage drops to 0V immediately, and then the power supply unit at address 1 enters the current loop, and the output voltage also drops to 0V immediately. According to the load current corresponding to the actual deep current-limiting load, finally when the address is M (M is less than or equal to N) enters the current loop, when the output voltage of the power supply unit at address M is stable above 0V, the power supply device realizes the stability of the total output voltage after the load is added, and then under the adjustment of the average value of the output voltage determined by the first power supply unit, Starting from the power supply unit with address M, the power supply units with addresses smaller than M exit the current loop in turn and enter the voltage loop to work. Finally, the first power supply unit works in the current loop, and the second power supply unit works in the voltage loop. Each power supply unit The output voltage is balanced, and thus the output power of the different power supply units in the whole power supply device is balanced. At the same time, each power supply unit determines the output current limit value of the unit according to the address of the unit, which is beneficial to improve the convenience of determining the output current limit value.

In this embodiment, the output current limit of the third power supply unit=the first current limit value+the first parameter value corresponding to the third power supply unit×the current limit adjustment parameter, the current limit The adjustment parameters are determined according to the preset rated current value and the preset steady current accuracy value.

Wherein, the rated current value of each power supply unit is the same, which is the preset rated current value. The preset steady current accuracy value is used to characterize the fluctuation degree of the output current of the power supply unit. In the specific implementation, even if the power supply unit controls the output according to the set output current value, its actual output current value may vary within a certain range around the set output current value, and the steady current accuracy value is used to represent this range of variation. For example, the actual output current of the power supply unit = set output current ± rated current value × steady current accuracy value.

Therefore, in order to ensure that in the process of sudden loading, each power supply unit in the power supply device can enter the current loop sequentially according to the order of the output current limit value from small to large (that is, the first parameter value is small to large), and in the first power supply Under the adjustment of the average value of the output voltage of the unit, exit the current loop in sequence according to the order of the output current limit value from large to small. It is necessary to ensure that among the two power units with the closest output current limit, the power unit with the smaller output current limit enters the current loop, and when the output is controlled according to the output current limit, even if the actual output current fluctuates, the actual output current will not change. Reach the output current limit of the power supply unit with a large output current limit, so as to prevent the power supply unit with a large output current limit from detecting that the actual output current sampling value reaches the output current limit of the unit and enter the current loop, that is, to avoid the output current limit. The two output cells with the closest values enter the current loop at the same time.

Therefore, the current limit adjustment parameters can be determined according to the preset rated current value and steady current accuracy value, that is, the output current limit value of each power supply unit can be determined according to the preset rated current value and steady current accuracy value, for example, according to the preset rated current value The current and steady current accuracy values determine the current limit adjustment parameters, so that the difference between any two closest output current limit values (take the absolute value) among the output current limit values of each power supply unit is not less than the rated current value × steady current value Current accuracy value, for example, the difference is equal to 2 × rated current value × steady current accuracy value. The current limit adjustment parameters are determined according to the preset rated current value and steady current accuracy value, which is beneficial to ensure that each power supply unit enters the current loop sequentially and improves the reliability of the power supply unit.

In a specific implementation, the current limit adjustment parameters can be pre-configured in each power supply unit, and each power supply unit can be directly based on the first parameter value corresponding to this unit, as well as the preset first current limit value and current limit value Adjust the parameters to determine the output current limit of the unit.

In this embodiment, the current limit adjustment parameter=(2÷preset parameter difference)×the preset steady current accuracy value×the preset rated current value, wherein, according to the The first parameter value corresponding to each power supply unit is from small to large or from large to small. When sorting the power supply units, the difference between the first parameter values corresponding to any two adjacent power supply units is the preset The parameters are poor.

Wherein, the difference between the first parameter values corresponding to any two adjacent power supply units is: among the first parameter values corresponding to the two adjacent power supply units, any one first parameter value minus the other first parameter value The absolute value of the numeric value of the parameter value. The difference between the first parameter values corresponding to any two adjacent power supply units is the preset parameter difference, that is, the difference between the first parameter values of any two adjacent power supply units is equal, and each power supply unit determines the output When the current limit is set, the current limit adjustment parameters are equal.

In the specific implementation, it is considered that when a deep current-limited load is suddenly added, the maximum output current peak may appear in the output series circuit of each power supply unit of the power supply device (that is, the maximum output current limit among the output current limits corresponding to each power supply unit) , in order to avoid damage to the power supply device or even the load due to excessive output current, the value of the current limit adjustment parameter cannot be set too large.

Therefore, it can be determined that (2÷preset parameter difference)×the preset steady current accuracy value×the preset rated current value is the current limit adjustment parameter, that is, the output current limit is closest to (the first parameter value Between the two power supply units closest to ), the absolute value of the difference of the output current limit value is 2×the preset steady current accuracy value×the preset rated current value, which is beneficial to ensure the voltage of the power supply unit While decreasing, avoid damage to the unit or device due to excessive peaks of the maximum output current.

In specific implementation, for the sake of convenience, the first parameter value corresponding to each power supply unit may be the address of the power supply unit, for example, the first parameter corresponding to each power supply unit is the address of the power supply unit, The address of each power supply unit is an integer from 0 to (N-1) respectively, as an example, the current limit value adjustment parameter=2×the preset steady current accuracy value×the preset rated current value; the third The output current limit value of the power supply unit (that is, any power supply unit in the power supply device) = the first current limit value + the address of the third power supply unit × 2 × the preset steady current accuracy value × the preset rated current value. Wherein, the preset steady current accuracy value may be 1%, that is, the current limit adjustment parameter value is 2% of the rated current value.

Described by a specific formula, the output current limit of the third power supply unit can be specifically determined by the following formula:

Isetm=(Iset+M×ΔI);

ΔI=2×Y×I;

Among them, Isetm is the output current limit of the third power supply unit, Iset is the first current limit value, M is the address of the third power supply unit, ΔI is the current limit adjustment parameter, Y is the steady current accuracy value, and I is the rated current value.

In this embodiment, referring to FIG. 2, any power supply unit in the power supply device includes: a control module, a power supply module, a diode module and a capacitor module;

The control module is connected to the control port of the power supply module, and the control module communicates with other power supply units through a communication bus. The input terminal of the power supply module is used to connect to an external power supply. The negative pole of the diode module and the first end of the capacitor module are combined and then connected to the positive output port (VO+) of the power supply unit, the negative output terminal of the power supply module is connected to the positive pole of the diode module, the capacitor module The second end of the connected circuit is connected to the negative output port (VO-) of the power supply unit;

The control module of the first power supply unit is used to realize the functions realized by the first power supply unit as described in Embodiment 1;

Wherein, referring to FIG. 3 , the diode module may be a diode, and the capacitor module may be an electrolytic capacitor.

In a specific implementation, the internal structure of each power supply unit may be the same, that is, the working principle of the internal modules of the first power supply unit may be referred to each second power supply unit.

In the specific implementation, considering that the output voltage of each power supply unit will gradually drop when the load demand current value exceeds its own current limit value, in order to avoid the output voltage of the power supply unit falling to 0, it will be affected by the output of other power supply units. Negative pressure and reverse charging of the internal capacitor module will cause damage to the device. The above-mentioned diode module is set inside each power supply unit as a circuit protection diode to clamp the negative voltage at both ends of the capacitor module to the conduction voltage drop of the diode. After the output voltage of each power supply unit drops to 0, the internal diode module is in positive phase On, the capacitor module will not be affected by the output of other power supply units.

Example 2:

This embodiment provides a power supply device, including the power supply unit in Embodiment 1 above, the power supply unit is a first power supply unit, at least one second power supply unit, the output port of the first power supply unit and each second power supply unit The output port of the power supply unit is connected to the load after being connected in series, any two power supply units in the power supply unit are communicatively connected through a communication bus, and the first power supply unit is the power supply unit with the smallest output current limit in the power supply unit.

Example 3:

This embodiment provides a power supply system, including the power supply unit described in Embodiment 1 or the power supply device described in Embodiment 2 above.

Compared with the prior art, the present invention provides a power supply unit, a power supply device and a power supply system, the power supply device includes a first power supply unit and at least one second power supply unit, the output port of the first power supply unit and each second power supply unit The output ports are connected in series to the load. The power supply unit with the smallest output current limit in the power supply unit is the first power supply unit. When the load demand current value is higher than the output current limit of the first power supply unit, the first power supply unit will voltage, determine the average value of the output voltage, and send it to each second power supply unit, so that each second power supply unit can determine the same output voltage setting value according to the output voltage value. That is, when the whole power supply device starts to enter the output power unbalanced state among different power supply units, the first power supply unit starts to determine the average output voltage according to the actual output voltage of each power supply unit, and sends it to each second power supply unit for adjusting the output voltage of each power supply unit. The output voltage setting value of each second power supply unit, and the output voltage setting value of each second power supply unit is the same value, because the current in the series circuit is the same, the output power between different power supply units of the power supply device can be gradually adjusted to be relatively relative. balanced state. It can be seen that the power supply unit provided by the present invention is applied in a power supply unit with series output, which is conducive to maintaining the output power balance of different power supply units in the power supply unit, improving the service life of each power supply unit and the entire power supply unit and the reliability of the power supply unit.

Finally, it needs to be emphasized that the present invention is not limited to the above-mentioned embodiments, the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications made within the spirit and principles of the present invention, equivalent Replacement, improvement, etc. should all be included within the protection scope of the present invention.

Claims

A power supply unit, characterized in that the power supply unit is a first power supply unit in a power supply device, the power supply device includes the first power supply unit and at least one second power supply unit, and the output of the first power supply unit Port and the output port of each second power supply unit are connected in series to the load, any two power supply units in the power supply unit are connected through a communication bus, and the first power supply unit is the one with the smallest output current limit in the power supply unit power supply unit;

The first power supply unit is used to obtain the actual output voltage of each power supply unit in the power supply device when the load demand current value is higher than the output current limit value of the first power supply unit; according to each power supply unit The actual output voltage of the actual output voltage, determine the average value of the output voltage; send the average value of the output voltage to each of the second power supply units, the average value of the output voltage is used for each of the second power supply units to perform the following operations: according to the The output voltage average value determines the output voltage setting value of the second power supply unit, and the output voltage setting values determined by each second power supply unit according to the output voltage average value are the same.
The power supply unit according to claim 1, wherein, in terms of sending the average value of the output voltage to each of the second power supply units, the first power supply unit is specifically used for:

When the difference between the actual output voltage of the first power supply unit and the system set voltage value is greater than a preset difference, the average value of the output voltage is sent to each of the second power supply units, and the load demand current is not high When the output current of the first power supply unit is limited, the output voltage setting value of each power supply unit in the power supply unit is the system setting voltage value.
The power supply unit according to claim 1, wherein the average value of the output voltage is specifically used for each of the second power supply units to perform the following operation: set the smaller of the average value of the output voltage and the system setting voltage value to The voltage value is determined as the output voltage setting value of the second power supply unit, and when the load demand current is not higher than the output current limit value of the first power supply unit, the output voltage of each power supply unit in the power supply unit The setting value is the system setting voltage value.
The power supply unit according to claim 1, wherein the output current limit values of any two different power supply units in the power supply device are different.
The power supply unit according to claim 4, wherein the output current limit of the third power supply unit in the power supply device is based on the preset first current limit value and the first parameter value corresponding to the third power supply unit Determined with the preset current limit adjustment parameter, the greater the first parameter value corresponding to the third power supply unit, the greater the difference between the output current limit value of the third power supply unit and the first current limit value ;

Wherein, the difference is proportional to the preset current limit adjustment parameter, the third power supply unit is any power supply unit in the power supply device, and each power supply unit in the power supply device corresponds to a first parameter value, the first parameter values corresponding to any two different power supply units are different, and the first parameter value corresponding to the first power supply unit is the smallest.
The power supply unit according to claim 5, wherein the output current limit of the third power supply unit=first current limit value+the first parameter value corresponding to the third power supply unit×the current limit value An adjustment parameter, the current limit adjustment parameter is determined according to a preset rated current value and a preset steady current accuracy value.
The power supply unit according to claim 6, wherein the current limit adjustment parameter=(2÷preset parameter difference)×the preset steady current accuracy value×the preset rated current value, Wherein, according to the first parameter values corresponding to each power supply unit in the power supply device from small to large or from large to small, when sorting the power supply units, the first parameter values corresponding to any two adjacent power supply units The difference is the difference of the preset parameters.
The power supply unit according to any one of claims 1-7, wherein any power supply unit in the power supply device comprises:

Control module, power module, diode module and capacitor module;

The control module is connected to the control port of the power supply module, and the control module communicates with other power supply units through a communication bus. The input terminal of the power supply module is used to connect to an external power supply. The negative pole of the diode module and the first end of the capacitor module are combined and then connected to the positive output port of the power supply unit. The negative output terminal of the power supply module is connected to the positive pole of the diode module and the second terminal of the capacitor module. After the terminal is combined, it is connected to the negative output port of the power supply unit;

The control module of the first power supply unit is used to realize the function realized by the first power supply unit according to any one of claims 1-7;

The power supply module of the first power supply unit is used to output an electrical signal for charging the load according to the output voltage setting value of the first power supply unit; the capacitor module of the first power supply unit is used to output the electric signal to the power supply module The electric signal of the first power supply unit is filtered; the diode module of the first power supply unit is used to prevent the output of the other power supply units from affecting the capacitor module of the first power supply unit.
A power supply device, characterized in that it comprises the power supply unit according to any one of claims 1-8, the power supply unit is a first power supply unit, at least one second power supply unit, and the output port of the first power supply unit The load is connected in series with the output port of each second power supply unit, any two power supply units in the power supply unit are communicatively connected through a communication bus, and the first power supply unit is the power supply with the smallest output current limit in the power supply unit unit.
A power supply system, characterized by comprising the power supply unit according to any one of claims 1-8 or the power supply device according to claim 9.