TWI741819B - Power supply device and power supply method thereof - Google Patents

Abstract

A power supply device and a power supply method thereof are provided. A charging power provided to a charging circuit by an AC power supply is adjusted according to a load power provided to a load by the AC power supply, so that total output power of the AC power supply is maintained below a preset total power. The total output power of the AC power is equal to the sum of the load power and the charging power.

Description

Power supply device and power supply method thereof

The present invention relates to a power supply device, and more particularly to a power supply device and a power supply method thereof.

Generally offline energy storage products such as Uninterruptible Power Supply (UPS)/PV inverter, due to hardware limitations, if you want to increase the input/output power, the power components in the hardware circuit A higher rated power must be selected, which increases its cost. If the power is provided in the form of a short-term overload output, the temperature will rise and the power can only be provided for a short time, so the power required by the load cannot be output for a long time.

The invention provides a power supply device and a power supply method thereof, which can effectively save hardware costs and improve power use efficiency.

The power supply device of the present invention includes a battery module, a charging circuit, and a control circuit. The charging circuit is coupled to the battery module and the AC power source. The AC power source provides charging power to the charging circuit and load power to the load, and the charging circuit charges the battery module. The control circuit is coupled to the charging circuit. The control circuit controls the charging circuit to adjust the charging power provided by the AC power supply to the charging circuit according to the load power provided by the AC power supply to the load, so that the total output power of the AC power supply is maintained below the preset total power. The total output power of the power supply is equal to the sum of the load power and the charging power.

In an embodiment of the present invention, the above-mentioned control circuit calculates the load average power based on multiple sampled load real-time powers obtained by sampling the load power at the sampling frequency within the most recent half cycle time of the AC power supply, and calculates the load average power according to the load average power The comparison result with the preset power adjusts the charging power.

In an embodiment of the present invention, when the average load power is greater than the preset power, the control circuit reduces the charging power so that the total output power of the AC power supply is maintained below the preset total power.

In an embodiment of the present invention, the update frequency of the aforementioned load average power is equal to the sampling frequency.

In an embodiment of the present invention, the aforementioned control circuit sets the charging power to the preset charging power when the charging power is lower than the preset charging power.

In an embodiment of the present invention, the above-mentioned power supply device further includes a power conversion circuit, which is coupled to the battery module, and converts the DC voltage provided by the battery module into an AC voltage when the AC power source is abnormal to supply power to the load . The first switch circuit is coupled to the control circuit, the power conversion circuit and the load. The second switch circuit is coupled to the control circuit, the AC power supply, and the load. The control circuit turns off the first switch circuit and the second switch circuit when the load power is greater than the preset total power.

The present invention also provides a power supply method of a power supply device including the following steps. Detect the load power provided by the AC power supply to the load and the charging power provided to the charging circuit. Adjust the charging power provided by the AC power supply to the charging circuit according to the load power provided by the AC power supply to the load, so that the total output power of the AC power supply is maintained below the preset total power, and the total output power of the AC power supply is equal to the load power and the charging power的和, wherein the charging circuit is used to charge the battery module.

In an embodiment of the present invention, the power supply method of the above-mentioned power supply device includes the following steps. The load power is sampled at the sampling frequency within the most recent half cycle of the AC power supply to obtain multiple sampled load real-time power. The average power of the load is calculated according to the real-time power of the multiple sampled loads. The charging power is adjusted according to the comparison result of the average power of the load and a preset power.

In an embodiment of the present invention, the power supply method of the power supply device described above includes reducing the charging power when the load average power is greater than the preset power, so that the total output power of the AC power supply is maintained below the preset total power.

In an embodiment of the present invention, the update frequency of the aforementioned load average power is equal to the sampling frequency.

In an embodiment of the present invention, the power supply method of the power supply device described above includes, when the charging power is lower than the preset charging power, setting the charging power to the preset charging power.

In an embodiment of the present invention, the aforementioned AC power supply supplies power to the load via a switching circuit, and the power supply method of the power supply device includes turning off the switching circuit when the load power is greater than the preset total power.

Based on the above, the embodiment of the present invention adjusts the charging power provided by the AC power supply to the charging circuit according to the load power provided by the AC power supply to the load, so that the total output power of the AC power supply is maintained below the preset total power, which can be improved without increasing the hardware. In the case of physical cost, it can meet the load power required by the load, improve the power usage efficiency, and avoid the temperature rise due to the power provided in the way of overload output, and then the electric energy required by the load can be output for a longer time.

FIG. 1 is a schematic diagram of a power supply device according to an embodiment of the present invention. Please refer to FIG. 1. The power supply device 100 may include a battery module 102, a charging circuit 104, and a control circuit 106. The battery module 102 is coupled to the charging circuit 104 and the control circuit 106. The charging circuit 104 is coupled to the control circuit 106 and the AC power source 108. The AC power source 108 Coupled to load 110. The AC power supply 108 can provide the charging power PCH to the charging circuit 104 and provide the load power PL to the load 110. The charging circuit 104 can charge the battery module 102. The control circuit 106 can control the charging circuit 104 to adjust the charging power PCH provided by the AC power supply 108 to the charging circuit 104 according to the load power PL provided by the AC power supply 108 to the load 110, for example, the total output power of the AC power supply 108 can be maintained at a preset total output power. Below power. For example, as shown in FIG. 2, when the total output power of the AC power supply 108 is equal to the sum of the load power PL and the charging power PCH, when the load power PL is increased to be greater than the preset power PLR, the control circuit 106 can reduce The charging power PCH, for example, when the load power PL is increased to the load power PLMAX, the difference power value PD between the load power PLMAX and the preset power PLR, and the charging power PCH is correspondingly reduced by the control circuit 106 to the preset charging power PCMIN at this time , And the power value PD different from the maximum charging power PCMAX, that is, the reduced charging power PCH is provided as the load power PL. In this way, the sum of the load power PL and the charging power PCH can be maintained at a fixed value (for example, the preset total power), so that the demand of the load 110 for the load power PL can be met, and the total output power of the AC power supply 108 does not exceed the preset value The total power, in turn, achieves the goal of saving hardware costs and improving power usage efficiency.

The preset charging power PCMIN is the minimum power value required for the normal operation of the charging circuit 104. In some embodiments, the preset charging power PCMIN can also be 0, and the load power PLMAX is the total output power of the AC power supply 108 minus After the charging power PCMIN is preset, the maximum load power that can be provided to the load 110 in the case of no overload output, that is, when the control circuit 106 reduces the charging power PCH to below the preset charging power PCMIN, the control circuit 106 will The charging power PCH is set to the preset charging power PCMIN to ensure the normal operation of the charging circuit 104 and avoid affecting the charging progress of the battery module 102.

(1) Furthermore, the control circuit 106 can calculate the load average power based on multiple sampled load real-time powers obtained by sampling the load power PL at a fixed sampling frequency within the most recent half cycle time of the AC power supply 108, and based on the load average power The comparison result with the preset power PLR adjusts the charging power PCH, that is, the control circuit 106 can adjust the charging power PCH in only half a cycle for the longest time, and the total output power of the AC power source 108 can be efficiently stabilized. For example, FIG. 3 is a schematic diagram of sampling the voltage and current output from the AC power supply to the load according to an embodiment of the present invention. Please refer to FIG. 3. The control circuit 106 can sample the voltage v(t) and current i(t) output from the AC power supply 108 to the load at a fixed frequency (for example, 10 kHz), for example, the voltage v(t) and current i( t) Sampling to obtain multiple sampling voltages v0~vh-1 and multiple sampling currents i0~ih-1, the load average power PAV1 in the cycle time T1 can be calculated by the following formula (1), where the cycle time T1 is the voltage 1/2 of the cycle length of v(t) and current i(t).

(1)

Among them, h is the number of samples in the half-cycle length of the AC power supply. The control circuit 106 can adjust the charging power PCH according to the comparison result of the load average power PAV1 and the preset power PLR. For example, when the load average power PAV1 is greater than the preset power PLR, the control circuit 106 can reduce the charging power PCH so that the AC power supply 108 The total output power is maintained below the preset total power, and the detailed adjustment method of the charging power PCH has been described in the above-mentioned embodiment, so it will not be repeated here. It is worth noting that the control circuit 106 can update the load average power at the same frequency as the sampling frequency of the voltage v(t) and current i(t), and based on the comparison result of the updated load average power and the preset power PLR By adjusting the charging power PCH, the charging power PCH can be adjusted quickly in response to the change of the load power PL, and the power usage efficiency can be greatly improved.

(2) For example, in the embodiment of FIG. 3, the control circuit 106 can sample the voltage v(t) and the current i(t) at a fixed frequency (for example, 10 kHz) within the cycle time T2 to obtain a plurality of sampled voltages v1~vh and A plurality of sampling currents i1~ih, wherein the cycle time T2 is shifted by a time Δt relative to the cycle time T1 on the time axis, and the time Δt may be equal to the reciprocal of the sampling frequency (10kHz). Similarly, the load average power PAV2 within the cycle time T2 can be calculated by the following formula (2), where the cycle time T2 is also 1/2 of the cycle length of the voltage v(t) and the current i(t).

(2)

The control circuit 106 can adjust the charging power PCH according to the comparison result of the load average power PAV2 and the preset power PLR. In this way, the adjustment of the charging power PCH is performed every time Δt, which can avoid the sudden change of the load power PL in a short time, causing the control circuit 106 to be too late to adjust the charging power PCH, so that high power usage efficiency can be achieved.

FIG. 4 is a schematic diagram of a power supply device according to another embodiment of the present invention, please refer to FIG. 4. In this embodiment, the power supply device 100 may further include a power conversion circuit 402 and switch circuits 404 and 406, wherein the power conversion circuit 402 is coupled to the battery module 102, the control circuit 106, and the switch circuit 404, and the switch circuit 404 is coupled to control The circuit 106 and the load 110, and the switch circuit 406 is coupled to the AC power supply 108, the control circuit 106 and the load 110. When the AC power source 108 is abnormal, the power conversion circuit 402 can convert the DC voltage provided by the battery module 102 into AC voltage to supply power to the load 110. The control circuit 106 can turn off the switch when the load power PL is greater than the preset total power. The circuit 404 and the switch circuit 406 are used to implement overload protection. The control circuit 106 of this embodiment can also control the charging circuit 104 to adjust the charging power PCH provided by the AC power source 108 to the charging circuit 104 according to the load power PL provided by the AC power source 108 to the load 110 as in the above-mentioned embodiment. Embodiments, so they will not be repeated here.

FIG. 5 is a flowchart of a power supply method of a power supply device according to an embodiment of the present invention, please refer to FIG. 5. It can be seen from the above embodiments that the power supply method of the power supply device may include the following steps. First, detect the load power provided to the load by the AC power source and the charging power provided to the charging circuit (step S502). Next, adjust the charging power provided by the AC power supply to the charging circuit according to the load power provided by the AC power supply to the load, so that the total output power of the AC power supply is maintained below the preset total power (step S504), where the total output power of the AC power supply can be It is equal to the sum of load power and charging power, and the charging circuit is used to charge the battery module. In some embodiments, the charging power must be maintained above the preset charging power to maintain the normal operation of the charging circuit, that is, when the charging power is reduced to less than the preset charging power, the charging power is still set to the preset charging power. Set the charging power. In addition, in other embodiments, the power supply device may also be provided with a switch circuit on the power supply path to the load. When the load power is greater than the preset total power, the switch circuit can be cut off to stop power supply to the load, and overload protection can be performed.

FIG. 6 is a flowchart of a power supply method of a power supply device according to another embodiment of the present invention, please refer to FIG. 6. In this embodiment, the charging power can be adjusted according to the load average power within the most recent half cycle of the AC power source. The power supply method of the power supply device of this embodiment can include the following steps. First, the load power is sampled at a sampling frequency within the most recent half cycle of the AC power supply to obtain multiple sampled load real-time powers (step S602). Then, the load average power is calculated according to the multiple sampled load real-time power (step S604). Then, the charging power is adjusted according to the comparison result of the average power of the load and the preset power (step S606). For example, when the average load power is greater than the preset power, the charging power can be reduced to keep the total output power of the AC power supply below the preset total power. The update frequency of the load average power can be equal to the sampling frequency, so that the charging power can be adjusted quickly in response to the change of the load power, and the power usage efficiency can be greatly improved.

FIG. 7 is a flowchart of a power supply method of a power supply device according to another embodiment of the present invention. Please refer to FIG. 7. The power supply method of the power supply device of this embodiment may include the following steps. First, it is determined whether the load power provided by the AC power supply to the load is greater than the preset total power (step S702). If the load power is greater than the preset total power, overload protection is performed (step S704), for example, power supply to the load can be stopped. If the load power is not greater than the preset total power, then it is determined whether the load power provided by the AC power source to the load is greater than the preset power (step S706). If the load power is not greater than the preset power, the charging power provided by the AC power supply to the charging circuit can be set to the maximum charging power (step S708), so that the charging circuit can charge the battery module in the most efficient manner, of which the maximum charging The power is less than the preset power. If the load power is greater than the preset power, the charging power provided by the AC power supply to the charging circuit can be reduced (step S710), so that the AC power supply can increase the load power provided to the load without causing the total output power of the AC power supply to exceed the preset total output power. Provides the electrical energy required by the load in the case of power. Then, it is determined whether the charging power provided by the AC power supply to the charging circuit is less than the preset charging power (step S712). If the charging power is not less than the preset charging power, the process of the power supply method ends. If the charging power is less than the preset charging power, the charging power is set to the preset charging power (step S714) to provide the electrical energy required for the normal operation of the charging circuit.

In summary, according to the present embodiment, the charging power provided by the AC power supply to the charging circuit is adjusted according to the load power provided by the AC power supply to the load, so that the total output power of the AC power supply is maintained below the preset total power. In the case of hardware cost, it can meet the load power required by the load, improve the power usage efficiency, and avoid the temperature rise due to the power supply in the way of overload output, and then the electric energy required by the load can be output for a longer time. In some embodiments, the load average power can be calculated based on the multiple sampled load real-time power obtained by sampling the load power at a fixed sampling frequency within the most recent half cycle time of the AC power supply, and the load average power and the predicted The charging power is adjusted by the comparison result of the power to quickly and efficiently stabilize the total output power of the AC power supply.

100: Power supply device

102: battery module

104: charging circuit

106: control circuit

108: AC power

110: load

402: Power Conversion Circuit

404, 406: switch circuit

PCH: Charging power

PL: Load power

PLR: preset power

PLMAX: Load power

PD: power difference

PCMIN: preset charging power

PCMAX: Maximum charging power

v(t): voltage

i(t): current

T1, T2: cycle time

v0~vh: sampling voltage

i0~ih: sampling current

PAV1, PAV2: Load average power

Δt: time

S502~S504, S602~S606, S702~S714: Power supply method steps of power supply device

FIG. 1 is a schematic diagram of a power supply device according to an embodiment of the present invention. Fig. 2 is a schematic diagram of load power and charging power according to an embodiment of the present invention. 3 is a schematic diagram of sampling the voltage and current output from an AC power supply to a load according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a power supply device according to another embodiment of the invention. FIG. 5 is a flowchart of a power supply method of a power supply device according to an embodiment of the present invention. FIG. 6 is a flowchart of a power supply method of a power supply device according to another embodiment of the present invention. FIG. 7 is a flowchart of a power supply method of a power supply device according to another embodiment of the present invention.

100: Power supply device

102: battery module

104: charging circuit

106: control circuit

108: AC power

110: load

PCH: Charging power

PL: Load power

Claims (10)

A power supply device includes: a battery module; a charging circuit coupled to the battery module and an AC power source, wherein the AC power source provides a charging power to the charging circuit and a load power to a load, the charging The circuit charges the battery module; and a control circuit coupled to the charging circuit, the control circuit controls the charging circuit to adjust the AC power provided to the charging circuit according to the load power provided by the AC power supply to the load Charging power, so that the total output power of the AC power supply is maintained below a preset total power, the control circuit sets the charging power as the preset charging power when the charging power is lower than a preset charging power, The total output power of the AC power supply is equal to the sum of the load power and the charging power. The power supply device according to claim 1, wherein the control circuit calculates a load average power based on a plurality of sampled load real-time powers obtained by sampling the load power at a sampling frequency within the most recent half cycle of the AC power supply , And adjust the charging power according to the comparison result of the average power of the load and a preset power. The power supply device according to claim 2, wherein when the load average power is greater than the preset power, the control circuit reduces the charging power so that the total output power of the AC power source is maintained below the preset total power. The power supply device according to claim 2, wherein the update frequency of the average power of the load is equal to the sampling frequency. The power supply device according to claim 1, further comprising: A power conversion circuit is coupled to the battery module, and when the AC power source is abnormal, the DC voltage provided by the battery module is converted into an AC voltage to supply power to the load; a first switch circuit is coupled to the The control circuit, the power conversion circuit and the load; and a second switch circuit coupled to the control circuit, the AC power supply and the load, wherein the control circuit turns off the load when the load power is greater than the preset total power The first switch circuit and the second switch circuit. A power supply method for a power supply device includes: detecting a load power provided by an AC power source to a load and a charging power provided to a charging circuit; and adjusting the load power according to the load power provided by the AC power source to the load The charging power provided by the AC power supply to the charging circuit so that the total output power of the AC power supply is maintained below a preset total power, and the total output power of the AC power supply is equal to the sum of the load power and the charging power, and When the charging power is lower than a preset charging power, the charging power is set as the preset charging power, wherein the charging circuit is used for charging a battery module. The power supply method of the power supply device according to claim 6, comprising: sampling the load power at a sampling frequency within the most recent half cycle of the AC power supply to obtain multiple sampled load real-time powers; Sampling the real-time power of the load to calculate a load average power; and The charging power is adjusted according to the comparison result of the load average power and a preset power. The power supply method of the power supply device according to claim 7, comprising: when the average power of the load is greater than the preset power, reducing the charging power so that the total output power of the AC power supply is maintained at the preset total power the following. The power supply method of the power supply device according to claim 7, wherein the update frequency of the average power of the load is equal to the sampling frequency. The power supply method of the power supply device according to claim 6, wherein the AC power supply supplies power to the load through a switching circuit, and the power supply method of the power supply device includes: when the load power is greater than the preset total power , Cut off the switch circuit.

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