Power supply module and power supply system

Abstract

The utility model discloses a power supply module and a power supply system, the power supply module comprises a power supply circuit, a current sampling circuit and an output control circuit, the power supply circuit is provided with an output end used for outputting power supply voltage; the output control circuit is electrically connected with the output end of the power supply circuit; and the output control circuit is used for collecting the output current of the power supply circuit and controlling the output voltage of the power supply circuit according to a preset mapping relation between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit is consistent with a preset current value. The utility model aims to improve the stability and reliability of the parallel operation of the power supply modules.

Description

Technical Field

[0001] The present application relates to the technical field of power supplies, and in particular, to a power supply module and a power supply system. Background Art

[0002] In the industrial field, different devices require different power supplies. Usually, a centralized power supply method is adopted to provide a stable bus voltage for different devices. However, the power supply specifications often cannot fully match the required power. For example, if the required power in a distribution box is 600W, a 960W power supply needs to be used; if the required power exceeds 960W, a higher-specification power supply is required. When used in an environment far below the rated specification and without power redundancy, the damage of the power supply will cause the system to stop working, which undoubtedly increases the cost and wastes resources, and at the same time reduces the system reliability. To achieve the parallel use of power supplies and increase the reliability of power supply, a common method is to use load current sharing, so that multiple power supplies supply power together, and there will be no situation where a single power supply output is overloaded and the power supply is damaged. For example, in the output impedance method, the output voltage is reduced as the output current increases, but the output voltage accuracy is sacrificed. For example, in the average current method, the current of the power supply itself is compared with the system reference current, and the output voltage is changed according to the comparison result to adjust the output current. It has high accuracy and good dynamic response, but new sampling ports need to be added to each power supply, and users need to add additional wiring. When the load bus is short-circuited and any one of the power supply modules connected to the bus cannot work, the bus voltage drop will cause the voltage of each power supply module to decrease, even reaching its lower limit, resulting in a failure. Summary of the Utility Model

[0003] The main object of the present utility model is to provide a power supply module and a power supply system, aiming to improve the reliability and stability of the power supply module during operation.

[0004] To achieve the above object, the present utility model provides a power supply module, which includes:

[0005] A power supply circuit having an output terminal for outputting a power supply voltage;

[0006] An output control circuit electrically connected to the output terminal of the power supply circuit;

[0007] The output control circuit is configured to collect the output current of the power supply circuit, and control the output voltage of the power supply circuit according to a preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit is consistent with a preset current value.

[0008] Optionally, the output control circuit includes:

[0009] A main control circuit;

[0010] A current sampling circuit, the first end of the current sampling circuit is electrically connected to the output end of the power supply circuit, and the second end of the current sampling circuit is electrically connected to the input end of the main control circuit;

[0011] The current sampling circuit is used to collect the output current of the power supply circuit and output a corresponding current sampling signal to the main control circuit;

[0012] The main control circuit is used to control the output voltage of the power supply circuit according to a preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit is consistent with a preset current value.

[0013] Optionally, the main control circuit includes:

[0014] A voltage control circuit, the input end of the voltage control circuit is electrically connected to the second end of the current sampling circuit;

[0015] A feedback loop circuit, the first input end of the feedback loop circuit is electrically connected to the output end of the voltage control circuit, and the second input end of the feedback loop circuit is electrically connected to the output end of the power supply circuit;

[0016] The voltage control circuit is used to receive the current sampling signal and output a corresponding reference voltage signal to the feedback loop circuit according to a preset mapping relationship between voltage and current, so that the feedback loop circuit adjusts the output voltage of the power supply circuit according to the output voltage of the power supply circuit and the reference voltage signal.

[0017] Optionally, the voltage control circuit includes:

[0018] A bias circuit, the bias circuit includes a first input end and a second input end, the first input end is electrically connected to the output end of the current sampling circuit, and the second input end is used to connect to a bias voltage;

[0019] An operational amplifier circuit, the operational amplifier circuit includes a positive input end, a negative input end and an output end, the positive input end is used to be grounded, and the negative input end is electrically connected to the output end of the bias circuit;

[0020] A subtractor circuit, the subtractor circuit includes a first subtraction input end, a second subtraction input end and an output end, the first subtraction input end is electrically connected to the output end of the operational amplifier circuit, the second subtraction input end is used to connect to a reference voltage, and the output end of the subtractor is electrically connected to the first input end of the feedback loop circuit.

[0021] Optionally, the feedback loop circuit includes:

[0022] An optocoupler device;

[0023] A voltage-dividing circuit, the first end of the voltage-dividing circuit is electrically connected to the positive electrode of the output end of the power supply circuit;

[0024] A comparison circuit, the comparison circuit includes a positive input end, a negative input end and an output end, the positive input end is electrically connected to the output end of the voltage control circuit, the negative input end is electrically connected to the second end of the voltage-dividing circuit, and the output end of the comparison circuit is electrically connected to the optocoupler device.

[0025] Optionally, the voltage-dividing circuit includes a first voltage-dividing resistor and a second voltage-dividing resistor;

[0026] Wherein, the first end of the first voltage-dividing resistor is electrically connected to the positive electrode of the output end of the power supply circuit, the second end of the first voltage-dividing resistor is electrically connected to the first end of the second voltage-dividing resistor, the second end of the second voltage-dividing resistor is electrically connected to the negative electrode of the output end of the power supply circuit, and the common connection end of the first voltage-dividing resistor and the second voltage-dividing resistor is electrically connected to the negative input end of the comparison circuit.

[0027] Optionally, the feedback loop circuit further includes:

[0028] A loop compensation circuit, the first end of the loop compensation circuit is electrically connected to the negative input end of the comparison circuit, and the second end of the loop compensation circuit is electrically connected to the output end of the comparison circuit.

[0029] Optionally, the loop compensation circuit includes a first capacitor, a second capacitor, a third capacitor, a first resistor and a second resistor;

[0030] Wherein, the first ends of the first capacitor and the second capacitor are interconnected with the output end of the comparison circuit, the second end of the first capacitor is electrically connected to the first end of the first resistor, the second ends of the first resistor and the second capacitor are interconnected with the second end of the voltage-dividing circuit, the first end of the third capacitor is electrically connected to the second end of the voltage-dividing circuit, the second end of the third capacitor is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the positive electrode of the output end of the power supply circuit.

[0031] Optionally, the output end of the power supply module is electrically connected to the load bus, and the power supply module further includes:

[0032] An anti-backflow circuit, the first end of the anti-backflow circuit is electrically connected to the output end of the power supply circuit, and the second end of the anti-backflow circuit is electrically connected to the load bus.

[0033] The present utility model also provides a power supply system, which includes a load bus bar and a plurality of power supply modules as described in any one of the above. Among them, the plurality of power supply modules are connected in parallel, and the output ends of the plurality of power supply modules are respectively electrically connected to the load bus bar.

[0034] The present utility model provides a power supply module, which includes a power supply circuit and an output control circuit. The power supply circuit has an output end for outputting a power supply voltage; the output control circuit is electrically connected to the output end of the power supply circuit; the output control circuit is used to collect the output current of the power supply circuit, and according to the preset mapping relationship between voltage and current and the collected output current, control the output voltage of the power supply circuit so that the current value corresponding to the output current of the power supply circuit is consistent with the preset current value.

[0035] In practical applications, the output control circuit will collect the output current of the power supply circuit, and according to the preset mapping relationship between voltage and current and the collected output current, control the output voltage of the power supply circuit, so as to make the current value corresponding to the current sampling signal consistent with the preset current value. In this way, when the power supply system includes a plurality of power supply modules connected in parallel, there is no need to add extra wiring, reducing the design cost, including the material and labor costs required by users. At the same time, the power supply system can realize the combined use of different powers and the same voltage, avoiding the situation that a certain power supply module is overloaded and burned out when multiple power supply modules are used in parallel, improving the reliability and stability of the power supply module of the present utility model, and further improving the reliability and stability of the power supply system. Description of the Drawings

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0037] Figure 1 It is a schematic diagram of the circuit module of an embodiment of the power supply module of the present utility model;

[0038] Figure 2 It is a schematic diagram of the circuit module of another embodiment of the power supply module of the present utility model;

[0039] Figure 3 It is a schematic diagram of the circuit module of yet another embodiment of the power supply module of the present utility model;

[0040] Figure 4 It is a schematic diagram of the circuit module of still another embodiment of the power supply module of the present utility model;

[0041] Figure 5 Schematic diagram of a circuit module of an embodiment of the power supply module of the present utility model;

[0042] Figure 6 Schematic circuit diagram of an embodiment of the output control circuit of the power supply module of the present utility model;

[0043] Figure 7 Schematic wiring diagram of parallel use of each power supply module in the prior art;

[0044] Figure 8 Schematic wiring diagram of parallel use of each power supply module of the present utility model;

[0045] Figure 9 Complete schematic circuit diagram of an embodiment of the power supply module of the present utility model;

[0046] Figure 10 Schematic circuit diagram of an embodiment of the power supply system of the present utility model;

[0047] Figure 11 Schematic diagram of the output voltage-output current curve of the power supply module of the present utility model;

[0048] Figure 12 Schematic diagram of the output current of each power supply module in the non-redundant power supply system of the present utility model;

[0049] Figure 13 Schematic diagram of the output current of each power supply module in the N+1 redundant power supply system of the present utility model.

[0050] Explanation of the reference numerals in the drawings:

[0051] Label Name Label Name 10 Power supply circuit 22 Current sampling circuit 20 Output control circuit 31 Voltage control circuit 32 Feedback loop circuit 33 Bias circuit 34 Operational amplifier circuit 35 Subtractor circuit 36 Opto-coupler device 37 Voltage dividing circuit 38 Comparison circuit 39 Loop compensation circuit

[0052] The realization, functional features and advantages of the object of the present utility model will be further described in conjunction with the embodiments with reference to the accompanying drawings. Detailed implementation manners

[0053] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0054] In addition, in the present utility model, descriptions such as "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0055] In the industrial field, different devices require different power supplies, and a centralized power supply method is often adopted to provide a stable bus voltage for different devices to use. However, the power supply specifications often cannot fully match the required power. For example, if the required power in a distribution box is 600W, a 960W power supply needs to be used; if the required power exceeds 960W, a higher-specification power supply is required for power supply. When used in an environment far below the rated specification and there is no redundancy in the power supply, the damage of the power supply will cause the system to stop working, which undoubtedly increases the cost and wastes resources, and at the same time reduces the system reliability. To achieve the parallel use of power supplies and increase the reliability of power supply, a common method is to use load current sharing so that multiple power supplies supply power together, and there will be no situation where a single power supply output is overloaded and the power supply is damaged. For example, in the output impedance method, the output voltage is reduced as the output current increases, but the output voltage accuracy is sacrificed. For example, in the average current method, the current of the power supply itself is compared with the system reference current, and the output voltage is changed according to the comparison result to adjust the output current. It has high accuracy and good dynamic response, but new sampling ports need to be added to each power supply, and additional wiring is required by the user. Moreover, when the load bus is short-circuited and any one of the power supply modules connected to the bus cannot work, the bus voltage drop will cause the voltage of each power supply module to decrease, even reaching its lower limit, resulting in a failure. Refer to Figure 7 , which is a wiring schematic diagram of the parallel use of each power supply module in the prior art.

[0056] For this reason, the present utility model proposes a power supply module, refer to Figure 1 , the power supply module includes:

[0057] A power supply circuit 10, the power supply circuit 10 having an output terminal for outputting a power supply voltage;

[0058] An output control circuit 20, the output control circuit 20 being electrically connected to the output terminal of the power supply circuit 10;

[0059] The output control circuit 20 is configured to collect the output current of the power supply circuit 10, and control the output voltage of the power supply circuit 10 according to a preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit 10 is consistent with a preset current value.

[0060] In this embodiment, the power supply circuit 10 can be implemented by a circuit composed of a transformer, a rectifier circuit, a filter circuit, etc., and is used to output a stable power supply voltage to provide the required power for the backend load to ensure the normal operation of the system.

[0061] In this embodiment, the output control circuit 20 includes:

[0062] A main control circuit;

[0063] A current sampling circuit 22, a first end of the current sampling circuit 22 is electrically connected to an output end of the power supply circuit 10, and a second end of the current sampling circuit 22 is electrically connected to an input end of the main control circuit;

[0064] The current sampling circuit 22 is configured to collect the output current of the power supply circuit 10 and output a corresponding current sampling signal to the main control circuit;

[0065] The main control circuit is configured to control the output voltage of the power supply circuit 10 according to a preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit 10 is consistent with a preset current value.

[0066] In this embodiment, the current sampling circuit 22 can be implemented by a sampling resistor, a triode, etc. In this embodiment, the current sampling circuit 22 includes a sampling resistor, a first end of the sampling resistor is electrically connected to an output end of the power supply circuit 10, and a second end of the sampling resistor is electrically connected to an input end of the output control circuit 20. The main control circuit can be implemented by a voltage control circuit 31 and a feedback loop circuit 32 composed of operational amplifiers. Among them, the preset mapping relationship between voltage and current is set in advance by R & D personnel. In this embodiment, the preset mapping relationship between voltage and current includes a control curve of the output voltage and output current of the power supply circuit (V-I control curve).

[0067] Specifically, the output control circuit 20 can collect the output current of the power supply circuit 10 and output a corresponding current sampling signal, control the output voltage of the power supply circuit 10 according to the V-I control curve, so that the current value corresponding to the current sampling signal detected by the output control circuit 20, that is, the output current of the power supply circuit 10 is consistent with the preset current value, where the preset current value is set in advance by the R & D personnel. It should be noted that the output current of the power supply circuit 10 flows through the sampling resistor to obtain a corresponding current sampling signal, where the current sampling signal includes the voltage across the sampling resistor. In this way, by sampling the output current of the power supply circuit 10 to obtain a corresponding current sampling signal, the output control circuit 20 controls the output voltage of the power supply circuit 10, and by adjusting the circuit parameters, a specific relationship between the output voltage and the output current of the power supply circuit 10 can be established, that is, the V-I control curve of a single power supply module, so as to realize the mapping relationship between the output voltage and the output current of the power supply module, make the output voltage of the power supply circuit 10 follow the change of the output current. When multiple power supply modules are connected in parallel to the load bus, it can not only ensure that the output voltage remains unchanged under light load, but also avoid the situation that a single power supply module is overloaded and burned out when multiple power supply modules are used in parallel. In addition, by adaptively adjusting the output voltage of a single power supply, it is possible to realize the parallel use of power supply modules with different powers and the same voltage without the user adding extra wiring, so as to solve the problem that the output power of the power supply system does not match the power required by the equipment.

[0068] In practical applications, the output control circuit 20 will collect the output current of the power supply circuit 10, and control the output voltage of the power supply circuit according to the preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the current sampling signal is consistent with the preset current value. In this way, when the power supply system includes multiple parallel power supply modules, there is no need to add extra wiring, reducing the design cost, including the material and labor costs required by the user. At the same time, the power supply system can realize the combined use of different powers and the same voltage, avoid the situation that a certain power supply module is overloaded and burned out when multiple power supply modules are used in parallel, improve the reliability and stability of the power supply module of the present invention, and thus improve the reliability and stability of the power supply system.

[0069] In another embodiment of the present invention, referring to Figures 2 to 3 , the main control circuit includes:

[0070] A voltage control circuit 31, the input end of the voltage control circuit 31 is electrically connected to the second end of the current sampling circuit;

[0071] A feedback loop circuit 32, the first input end of the feedback loop circuit 32 is electrically connected to the output end of the voltage control circuit 31, and the second input end of the feedback loop circuit 32 is electrically connected to the output end of the power supply circuit 10;

[0072] The voltage control circuit 31 is configured to receive the current sampling signal and output a corresponding reference voltage signal to the feedback loop circuit 32 according to a preset mapping relationship between voltage and current, so that the feedback loop circuit 32 adjusts the output voltage of the power supply circuit according to the output voltage of the power supply circuit 10 and the reference voltage signal.

[0073] Wherein, the voltage control circuit 31 includes:

[0074] A bias circuit 33, the bias circuit 33 includes a first input terminal and a second input terminal, the first input terminal is electrically connected to the output terminal of the current sampling circuit 22, and the second input terminal is used for accessing a bias voltage;

[0075] An operational amplifier circuit 34, the operational amplifier circuit 34 includes a positive input terminal, a negative input terminal and an output terminal, the positive input terminal is grounded, and the negative input terminal is electrically connected to the output terminal of the bias circuit 33;

[0076] A subtractor circuit 35, the subtractor circuit 35 includes a first subtraction input terminal, a second subtraction input terminal and an output terminal, the first subtraction input terminal is electrically connected to the output terminal of the operational amplifier circuit 34, the second subtraction input terminal is used for accessing a reference voltage, and the output terminal of the subtractor is electrically connected to the first input terminal of the feedback loop circuit 32.

[0077] In this embodiment, the voltage control circuit 31 can be implemented by a circuit composed of a bias circuit 33, an operational amplifier circuit 34 and a subtractor circuit 35. The bias circuit 33 is configured to bias the current sampling signal output by the current sampling circuit 22 and then output it to the operational amplifier circuit 34, so that the operational amplifier circuit 34 performs an inverse proportional amplification process on the electrical signal output by the bias circuit 33 and then outputs it to the subtractor circuit 35. The subtractor circuit 35 processes it and outputs a corresponding feedback voltage, so that the feedback voltage serves as a new reference voltage for the power supply loop, thereby controlling the output voltage of the power supply circuit 10.

[0078] Reference Figure 6, a sampling resistor Rcs is connected in series at the output end of the power supply circuit 10. That is, the current sampling circuit 22 samples the output current of the power supply circuit 10 to obtain a negative voltage Vout_cs, and then a bias voltage (preset electrical signal) is introduced. The bias circuit 33 adds the bias voltage to the negative voltage Vout_cs to obtain Vcs, and the operational amplifier circuit 34 amplifies the voltage signal Vcs output by the bias circuit 33 to obtain V_ref-bias. Then, the reference voltage is subtracted from V_ref-bias by the subtractor circuit 35 to obtain a feedback voltage FB_ref, and the feedback voltage is used as a new reference voltage, that is, a new reference voltage of the power supply loop, to adjust the output voltage of the power supply circuit 10.

[0079] It should be noted that by adjusting the bias circuit 33, the inflection point current of the output voltage of the power supply circuit can be controlled; by the operational amplifier circuit 34, the amplitude of the output voltage decreasing with the output current can be controlled; by the subtractor circuit 35, a new reference voltage can be obtained, and the new reference voltage is compared with the output voltage obtained by the voltage dividing circuit to adjust the output voltage of the power supply circuit in real time. That is, the bias voltage is used to control the inflection point current Ia. When the output current Io of the power supply circuit 10 is less than the inflection point current Ia, Vcs is positive. When the output current Io of the power supply circuit 10 is greater than the inflection point current Ia, Vcs is negative. When the output current Io of the power supply circuit 10 is equal to the inflection point current Ia, Vcs is 0V. When I o ≤I a , V_ref-bias is 0V. At this time, the output current has not reached the preset value Ia, and the output current is within the acceptable range of the power supply circuit 10. Therefore, there is no need to adjust the reference voltage, and the power supply circuit 10 can output at the maximum voltage. That is, without changing the reference voltage, the output voltage of the power supply circuit 10 will not be overloaded and burned out.

[0080] Through the above settings, the output voltage of the power supply circuit 10 can be adaptively adjusted according to its own output voltage to realize the adjustment of the output voltage of the power supply module. In this way, in practical applications, when multiple power supply modules are connected in parallel, it can be avoided that the output voltage of a certain power supply module is too high and causes overload and burnout, improving the reliability and stability of the power supply system.

[0081] In an embodiment of the present invention, referring to Figure 5 , the feedback loop circuit 32 includes:

[0082] An optocoupler device 36;

[0083] A voltage dividing circuit 37, the first end of the voltage dividing circuit 37 is electrically connected to the positive pole of the output end of the power supply circuit 10;

[0084] Comparator circuit 38, the comparator circuit 38 includes a positive input terminal, a negative input terminal and an output terminal, the positive input terminal is electrically connected to the output terminal of the voltage control circuit 31, the negative input terminal is electrically connected to the second terminal of the voltage dividing circuit 37, and the output terminal of the comparator circuit 38 is electrically connected to the optocoupler device 36.

[0085] In this embodiment, the voltage dividing circuit 37 can be implemented by a resistive voltage dividing circuit 37 or a capacitive voltage dividing circuit 37. The comparator circuit 38 can be implemented by an operational amplifier. In this embodiment, a resistive voltage dividing circuit 37 is selected. The voltage dividing circuit 37 includes a first voltage dividing resistor and a second voltage dividing resistor; wherein, the first end of the first voltage dividing resistor is electrically connected to the positive pole of the output terminal of the power supply circuit 10, the second end of the first voltage dividing resistor is electrically connected to the first end of the second voltage dividing resistor, the second end of the second voltage dividing resistor is electrically connected to the negative pole of the output terminal of the power supply circuit, and the common connection end of the first voltage dividing resistor and the second voltage dividing resistor is electrically connected to the negative input terminal of the comparator circuit 38.

[0086] Specifically, referring to Figure 9 , Figure 9 is the complete circuit schematic diagram of an embodiment of the power supply module of the present invention, representing the internal circuit of a power supply module. Figure 10 It is the output voltage feedback circuit of the power supply circuit. The optocoupler device 36 is used to control the operation of the transformer to output the corresponding DC voltage to the power supply output terminal after voltage conversion. That is, the output voltage feedback circuit compares the actually sampled output voltage with the reference voltage, and feeds back the comparison result to the power supply control circuit (control chip) through the optocoupler device 36, so that the control chip controls the operation of the power supply power circuit, thereby realizing the adjustment and control of the output voltage of the power supply circuit 10. Among them, referring to Figure 6 , the power supply circuit includes a power supply power circuit and a power supply control circuit, and the power supply control circuit is used to control the working state of the power supply power circuit. The reference voltage is the new reference voltage described in the above embodiment. The first resistor R11 and the second resistor R12 form the output voltage sampling circuit of the power supply loop, which is used to collect the output voltage of the power supply module. R9 is the optocoupler series resistor, and R10 is the optocoupler parallel resistor.

[0087] Combined with the above embodiment content, taking a 12V power supply as an example, derating starts at 90% load. At 90% load, the output voltage is 12V; at 100% load, the output voltage is 11.7V. Due to considering the production consistency problem, the power supply module enters overcurrent protection at 110% load, and the output voltage is 11.4V at this time.

[0088] Referring to Figure 11, U0 is the rated output voltage of the power supply module, I0 is the rated output current of the power supply module, Ia is the current corresponding to the start of the output voltage drop of the power supply module, Ua is the actual voltage when the power supply module is fully loaded, Ib is the overcurrent protection point of the power supply module, and Ub is the voltage at overcurrent protection of the power supply module, that is, the lowest output voltage. Among them, Ia, Ib, Ua, and Ub can all be adjusted according to the actual bus voltage requirements.

[0089] It should be noted that due to factors such as device accuracy and ambient temperature, the output voltages of power supplies in large-scale production will inevitably have offsets and cannot be completely guaranteed to be consistent. To make the loads between multiple power supply modules as close as possible, the wires at the DC output end are used as uniformly as possible. In addition, ignoring the influence of DC cables, etc., calculate the current distribution of the power supply system in various situations to further adjust the parameters to make the loads between each power supply module as close as possible. Two indicators, the current sharing accuracy δ and the power load regulation rate ρ, need to be introduced.

[0090] Among them, the calculation formula for the current sharing accuracy is: δ = [△I omax / (I o / N)] × 100%; the power load regulation rate is: ρ = |(V o - V half ) / V half | × 100%; where, △I omax is the difference between the maximum output current and the minimum output current of the parallel modules themselves; I o is the total output current; N is the number of parallel modules; V o is the output voltage of the power supply system, and the no-load condition does not participate in the calculation of the load regulation rate; V half is the output voltage at half load (50% full load), which in this article refers to the output voltage of the system with a 50% load

[0091] Taking a 12V / 7A power supply module as an example, for mass-produced power supply modules, the highest output voltage is 12.2V and the lowest is 11.75V. Select 10 pcs of power supply modules and simulate the most extreme situation where the highest and lowest voltages appear simultaneously. The output voltages are evenly distributed between 11.75V and 12.2V. Observe the output conditions of each power supply through different total required currents of the load bus. Select the no-load, half-load, and full-load conditions of the load bus respectively, and the calculation results are as Figure 12As shown in the figure; according to the previous parameter settings, the load bus voltage regulation rate of the power supply system is only 2.30%. When multiple power supply modules are used in parallel, a high voltage regulation rate can still be ensured. Under light load, the power supply modules with higher output voltage supply power preferentially, so the current differences among the power supply modules are large and the current sharing accuracy δ is very poor. At this time, the effect of the parallel system is similar to the automatic master-slave control method. The load bus current is mainly supplied by one or more power supply modules, and the other power supply modules are in standby state. Under heavy load, the current sharing accuracy increases. At this time, each load has a load, but the current sharing accuracy δ is still not high. In addition, when the load is full, power supply module 1 has exceeded the rated load, and the output current is close to the overcurrent point of the power supply, there is a possibility of triggering overcurrent protection, and it is very likely to cause overload and burnout.

[0092] Therefore, to ensure the performance of power supply module 1 with the largest output current, the parameters are further optimized to keep the inflection point Ia unchanged; by adjusting the amplification factor n of the operational amplifier, the full-load voltage Ua is reduced, so that the full-load of the power supply drops by 0.5V compared with the normal voltage. At the same time, in order to make power supply module 1 work within a reasonable range, power supply module 11 is added as a system redundant backup, assuming that the output voltage of power supply module 11 is the typical value of 12V. The results after recalculation are as Figure 13 shown. It can be seen that after reducing the full-load voltage Ua and adding power supply module 11 as a redundant power supply module, power supply module 1 can work normally within the rated load range, and the load bus voltage regulation rate is further optimized. Under heavy load, the current sharing accuracy δ is greatly improved, which also has an improvement effect on the life of each power supply under heavy load. It should be noted that due to the influence of DC cables, output diodes, Oring circuits, etc., in actual applications, there will be no situation where power supply modules 6 to 10 have no output at all. Here, it is only used as a reference for the worst case.

[0093] In this embodiment, the power supply system composed of multiple power supply modules in parallel can achieve a high voltage regulation rate. Also, since the output voltage of a single power supply module will adaptively adjust the output according to its own V-I curve, under light load conditions, the power supply will be concentrated on some power supply modules, the current sharing effect is poor but the output voltage offset is small; under heavy load conditions, the current sharing effect among the power supply modules is good, meeting the life requirements of the power supply system. At this time, the load bus voltage is determined by the power supply module with the minimum output voltage of the power supply system.

[0094] It can be understood that when the total power required by the power supply system is less than the output power of N power supply modules used in parallel, it is recommended to use N + 1 power supply modules for system redundancy to avoid the overwork of the power supply module with the largest output current. Considering the performance of the power supply system, to improve the reliability of the power supply system, it is recommended that N ≤ 10.

[0095] With the above settings, the power module of the present utility model can be applied to a power system, which can avoid large fluctuations in the load bus voltage while ensuring a high voltage regulation rate. Moreover, the output current of each parallel-connected power module adapts to the actual situation, and compared with the average current method in the prior art, it does not require the user to make additional wiring, and only needs to adjust parameters such as the output voltage and sampling resistance of a single power supply separately. In addition, the user can flexibly adjust values such as Ia, Ib, Ua, and Ub to meet the requirements for the current sharing accuracy and voltage regulation rate of the power system. In this way, the design cost of the power system is reduced, and the reliability and stability of the power system are improved.

[0096] In an embodiment of the present utility model, referring to Figure 5 , the feedback loop circuit 32 further includes:

[0097] A loop compensation circuit 39, the first end of the loop compensation circuit 39 is electrically connected to the negative input end of the comparison circuit 38, and the second end of the loop compensation circuit 39 is electrically connected to the output end of the comparison circuit 38.

[0098] The loop compensation circuit 39 includes a first capacitor, a second capacitor, a third capacitor, a first resistor, and a second resistor;

[0099] Wherein, the first end of the first capacitor and the first end of the second capacitor are interconnected with the output end of the comparison circuit 38, the second end of the first capacitor is electrically connected to the first end of the first resistor, the second end of the first resistor and the second end of the second capacitor are interconnected with the second end of the voltage dividing circuit 37, the first end of the third capacitor is electrically connected to the second end of the voltage dividing circuit 37, the second end of the third capacitor is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the output end of the power supply circuit 10.

[0100] In this embodiment, referring to Figure 10 , the first capacitor C7 and the first resistor R14 are connected in series and then connected in parallel with the second capacitor C6, and the third capacitor C8 and the second resistor R13 are connected in series and then connected in parallel with the first voltage dividing resistor R11.

[0101] Specifically, by adding a loop compensation circuit 39 composed of the first capacitor C7, the second capacitor C6, the third capacitor C7, the first resistor R14, and the second resistor R13 as the compensation network of the comparison circuit 38, the comparison circuit 38 compares the output voltage sampled by the voltage dividing circuit connected to its negative input end with the new reference voltage at the positive input end. The loop compensation circuit 39 feeds the output signal of the comparison circuit 38 back to the negative input end of the comparison circuit 38 after being processed by the compensation network, so that the response of the comparison circuit 38 is faster and more accurate.

[0102] The setting of the feedback compensation circuit can adjust the output voltage of the power supply circuit 10 more quickly and accurately, so as to improve the stability of the power supply module, and further improve the stability and reliability of the power supply system. At the same time, the feedback compensation circuit composed of resistor and capacitor elements reduces the circuit design cost to a certain extent.

[0103] In one embodiment, the output end of the power supply module is electrically connected to the load bus, and the power supply module further includes:

[0104] An anti-backflow circuit, the first end of the anti-backflow circuit is electrically connected to the output end of the power supply circuit 10, and the second end of the anti-backflow circuit is electrically connected to the load bus.

[0105] In this embodiment, the anti-backflow circuit can be implemented by using diodes, MOS transistors, etc. In this embodiment, a diode is selected to implement it.

[0106] Specifically, the anode of the diode is electrically connected to the output end of the power supply module, and the cathode of the diode is electrically connected to the load bus. Under normal circumstances, the output power of the power supply module will be output to the load bus through its own output end to supply power to the load electrically connected to the load bus. At this time, the diode is in the forward conduction state, with a small resistance value and a small voltage drop, and can be regarded as a wire, which will not affect the power supply system. The power supply module can normally output the supply voltage to supply power to the load. When a reverse voltage appears at the output end of the power supply module, for example, the voltage of the load bus is higher than the voltage of the power supply module with a lower output voltage or a single power supply module fails and pulls down the voltage of the load bus. At this time, due to the one-way conduction characteristic of the diode, the diode is in the reverse cut-off state at this time. Due to the high voltage drop, it is equivalent to an open circuit state. At this time, the voltage of the load bus will not flow back into the power supply module, avoiding the damage of the power supply module caused by high voltage backflow.

[0107] The setting of the anti-backflow circuit can prevent the voltage of the load bus from flowing back into the power supply module with a lower output voltage when multiple power supply modules are used in parallel. In this way, the power supply module is effectively protected, the safety of the power supply module is improved, and further the stability and reliability of the power supply system are improved.

[0108] The present invention also proposes a power supply system, the power supply system includes a load bus and multiple power supply modules as described in any one of the above, wherein, the multiple power supply modules are connected in parallel, and the output ends of the multiple power supply modules are respectively electrically connected to the load bus. Refer to Figure 8 , which is a wiring schematic diagram for the parallel use of each power supply module.

[0109] It should be noted that since the power supply system of the present utility model is based on the above-mentioned power supply module, the embodiments of the power supply system of the present utility model include all the technical solutions of all the embodiments of the above-mentioned power supply module, and the achieved technical effects are also exactly the same, so they will not be elaborated here.

[0110] The above are only the optional embodiments of the present utility model, and do not limit the patent scope of the present utility model accordingly. Any equivalent structural transformation made by using the content of the specification and drawings of the present utility model under the inventive concept of the present utility model, or direct / indirect application in other related technical fields is included in the patent protection scope of the present utility model.

Claims

1. A power module, characterized in that: The power module comprises: A power supply circuit having an output terminal for outputting a power supply voltage; an output control circuit, the output control circuit being electrically connected to an output end of the power supply circuit; The output control circuit is used to collect the output current of the power supply circuit, and control the output voltage of the power supply circuit according to a preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit is consistent with the preset current value.

2. The power module according to claim 1, characterized in that: The output control circuit comprises: Main control circuit; A current sampling circuit, wherein a first end of the current sampling circuit is electrically connected to an output end of the power supply circuit, and a second end of the current sampling circuit is electrically connected to an input end of the main control circuit; The current sampling circuit is used to collect the output current of the power supply circuit and output a corresponding current sampling signal to the main control circuit; The main control circuit is used to control the output voltage of the power supply circuit according to the preset mapping relationship between voltage and current and the collected output current, so that the current value corresponding to the output current of the power supply circuit is consistent with the preset current value.

3. The power module according to claim 2, characterized in that: The main control circuit comprises: A voltage control circuit, wherein an input end of the voltage control circuit is electrically connected to a second end of the current sampling circuit; a feedback loop circuit, wherein a first input end of the feedback loop circuit is electrically connected to an output end of the voltage control circuit, and a second input end of the feedback loop circuit is electrically connected to an output end of the power supply circuit; The voltage control circuit is used to receive the current sampling signal and output a corresponding reference voltage signal to the feedback loop circuit according to a preset mapping relationship between voltage and current, so that the feedback loop circuit adjusts the output voltage of the power supply circuit according to the output voltage of the power supply circuit and the reference voltage signal.

4. The power module according to claim 3, characterized in that: The voltage control circuit comprises: A bias circuit, the bias circuit comprising a first input terminal and a second input terminal, the first input terminal is electrically connected to the output terminal of the current sampling circuit, and the second input terminal is used to access a bias voltage; An operational amplifier circuit, the operational amplifier circuit comprising a positive input terminal, a negative input terminal and an output terminal, the positive input terminal is used for grounding, and the negative input terminal is electrically connected to the output terminal of the bias circuit; A subtractor circuit, the subtractor circuit comprising a first subtraction input terminal, a second subtraction input terminal and an output terminal, the first subtraction input terminal is electrically connected to the output terminal of the operational amplifier circuit, the second subtraction input terminal is used to access a reference voltage, and the output terminal of the subtractor is electrically connected to the first input terminal of the feedback loop circuit.

5. The power module according to claim 3, characterized in that: The feedback loop circuit comprises: Optocoupler devices; A voltage divider circuit, wherein a first end of the voltage divider circuit is electrically connected to a positive electrode of an output end of the power supply circuit; A comparison circuit, the comparison circuit comprising a positive input terminal, a negative input terminal and an output terminal, the positive input terminal is electrically connected to the output terminal of the voltage control circuit, the negative input terminal is electrically connected to the second terminal of the voltage divider circuit, and the output terminal of the comparison circuit is electrically connected to the optocoupler device.

6. The power module according to claim 5, characterized in that: The voltage dividing circuit comprises a first voltage dividing resistor and a second voltage dividing resistor; Among them, the first end of the first voltage-dividing resistor is electrically connected to the positive output terminal of the power supply circuit, the second end of the first voltage-dividing resistor is electrically connected to the first end of the second voltage-dividing resistor, the second end of the second voltage-dividing resistor is electrically connected to the negative output terminal of the power supply circuit, and the common connection end of the first voltage-dividing resistor and the second voltage-dividing resistor is electrically connected to the negative input terminal of the comparison circuit.

7. The power module according to claim 5, characterized in that: The feedback loop circuit further includes: A loop compensation circuit, wherein a first end of the loop compensation circuit is electrically connected to the negative input end of the comparison circuit, and a second end of the loop compensation circuit is electrically connected to the output end of the comparison circuit.

8. The power module according to claim 7, characterized in that: The loop compensation circuit includes a first capacitor, a second capacitor, a third capacitor, a first resistor and a second resistor; Among them, the first end of the first capacitor and the first end of the second capacitor are interconnected with the output end of the comparison circuit, the second end of the first capacitor is electrically connected to the first end of the first resistor, the second end of the first resistor and the second end of the second capacitor are interconnected with the second end of the voltage divider circuit, the first end of the third capacitor is electrically connected to the second end of the voltage divider circuit, the second end of the third capacitor is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the positive output end of the power supply circuit.

9. The power module according to claim 1, characterized in that: The output end of the power module is electrically connected to the load bus, and the power module further includes: A backflow prevention circuit, wherein a first end of the backflow prevention circuit is electrically connected to the output end of the power supply circuit, and a second end of the backflow prevention circuit is electrically connected to the load bus.

10. A power supply system, characterized in that: The power supply system comprises a load bus and a plurality of power supply modules as claimed in any one of claims 1 to 9, wherein the plurality of power supply modules are connected in parallel, and output ends of the plurality of power supply modules are electrically connected to the load bus respectively.

Images