Power supply additional control system

Abstract

The utility model relates to a power supply additional control system, which is additionally arranged on one side of a direct current bus of a power supply load side current converter and is characterized in that an unloading circuit is used for dissipating excess energy; the signal acquisition circuit is used for detecting power and current on two sides of the load side current converter; the unloading circuit control circuit comprises a logic control and protection module which is used for generating an additional control signal to control a pulse generation module based on a direct current bus current and a load side current value acquired by signals, generating a trigger signal based on a power deviation between an acquired direct current bus power and a load side power, and outputting the trigger signal. And in combination with an additional control signal output by the logic control and protection module, an unloading circuit control signal is output so as to control the switching of the unloading circuit. Compared with the prior art, the control circuit generates signals to control the switching of the unloading circuit, so that redundant power is dissipated, the load side converter is protected from being impacted by large current, the power supply is prevented from being damaged by faults, and the service life of electronic components is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to power supply control technical field especially, it is a kind of power supply control system. BACKGROUND

[0002] When the power supply of large load supplies power, when load cutout or stop working and other load mutation conditions occur, the current of load side will drop sharply, since the current of DC bus side needs time to slowly fall back, larger power difference will be generated between the two sides of load side converter, i.e. between load and DC bus, which is easy to cause damage to internal electronic components of load side converter.

[0003] Traditional power supply overcurrent, over-power protection generally only considers the overload risk of adapter caused by excessive current consumption of load, but does not consider the influence of power overshoot of DC bus side on converter caused by instantaneous fall back of load side current after large load cutout. INVENTION CONTENTS

[0004] The utility model aims at overcoming the defects of the prior art and provides a power supply control system.

[0005] The utility model discloses the purpose can be realized through the following technical scheme:

[0006] A power supply power supply additional control system, the system is set on the DC bus side of power load side converter: unloading circuit, signal acquisition circuit and unloading circuit control circuit;Wherein, the unloading circuit control circuit includes:

[0007] Logic control and protection module, input end connects signal acquisition circuit, includes connected subtracter and hysteresis comparator and connected differential circuit and falling edge trigger delay timer, the output end of falling edge trigger delay timer is connected with the enable end of hysteresis comparator;

[0008] Control pulse generation module, input end connects signal acquisition circuit, and includes connected subtracter, proportional-integral controller, pulse generator and controlled switch in proper order, and the controlled end of controlled switch is connected with the output end of hysteresis comparator.

[0009] As preferred technical scheme, the unloading unit at least includes thyristor, and the anode of the thyristor is connected with the anode of the DC bus.

[0010] As preferred technical scheme, the signal acquisition circuit includes current transformer and voltage transformer arranged on load side and DC bus side.

[0011] As preferred technical scheme, the logic control and protection module includes: subtracter, hysteresis comparator, differential circuit and falling edge trigger delay timer.

[0012] As a preferred technical solution, the input end of the subtracter is connected with the signal acquisition circuit, and the output end of the subtracter is connected with the input end of the proportional integral controller.

[0013] The input end of the subtracter is connected with the signal acquisition circuit, and the output end of the subtracter is connected with the input end of the proportional integral controller.

[0014] The input end of the subtracter is connected with the signal acquisition circuit, and the output end of the subtracter is connected with the input end of the proportional integral controller.

[0015] As a preferred technical solution, the input end of the subtracter is connected with the signal acquisition circuit, and the output end of the subtracter is connected with the input end of the proportional integral controller.

[0016] As a preferred technical solution, the additional control system further comprises a drive output module, the drive output module is a drive amplification unit, the input end is connected with the output of the control pulse generation module, and the output end of the drive output module is connected with the unloading circuit.

[0017] Compared with the prior art, the power supply additional control circuit has the following beneficial effects:

[0018] The power supply additional control circuit has the following beneficial effects: BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 FIG. 1 is a structural schematic diagram of the power supply additional control system of the utility model;

[0020] Figure 2 FIG. 4 is a circuit structure diagram of the logic control and protection module circuit of the utility model;

[0021] Figure 3 FIG. 5 is a circuit structure diagram of the control pulse generation module circuit of the utility model. DETAILED DESCRIPTION

[0022] The utility model will be described in detail below in combination with the drawings and specific embodiments. The embodiments are implemented on the premise of the technical scheme of the utility model, and detailed implementation modes and specific operation processes are given, but the protection scope of the utility model is not limited to the following embodiments.

[0023] Embodiment 1

[0024] The utility model provides a kind of power supply additional control system, as shown in Figure 1 It includes unloading unit for realizing dissipation of excess energy;Signal acquisition circuit for detecting power and current on both sides of load side converter;Logic control and protection module for generating additional control signal based on DC bus current and load side current value collected by signal acquisition circuit;Control pulse generation module for generating unloading circuit control signal based on power deviation of DC bus power and load side power collected by signal acquisition circuit and unloading control signal output by logic control and protection module.

[0025] Among them, unloading unit is used to handle surplus power of AC system in case of AC system failure, and the unloading unit at least includes thyristor, and the anode of the thyristor is connected with the anode of the DC bus.

[0026] Signal acquisition circuit includes current transformer CT and voltage transformer PT arranged on load side and DC bus side, for acquiring current and power on both sides of load side converter.

[0027] As shown in Figure 2 , logic control and protection module includes subtracter, hysteresis comparator, differential circuit and falling edge trigger delay. The DC bus current and load side current value collected by the signal acquisition circuit are input to the hysteresis comparator after being subtracted by the subtracter;The hysteresis comparator compares with the upper and lower limits of the set current difference value;The load side current after passing through the differential circuit obtains its change rate, and its output is input to the enable end of the hysteresis comparator after being delayed by a falling edge trigger delay. When the load is cut out, the load side current rapidly drops, and the enable signal is output to make the hysteresis comparator start comparison;After a short delay, the comparison stops when the current stops dropping, ensuring the stability of DC bus power control. When the current difference value is within the set reference difference value, the additional signal Ctrl Is "0";When the current difference value exceeds the set reference difference value, the additional control signal Ctrl Output is "1" and input to control pulse generation module to control it to generate unloading circuit control signal.

[0028] As shown in Figure 3 , control pulse generation module includes subtracter, proportional-integral controller, pulse generator and controlled switch. The power deviation of load side converter on both sides collected by signal acquisition circuit is input to proportional-integral controller, to calculate duty cycle , and trigger signal is generated by pulse generator according to duty cycle ; The input of controlled switch position 1 is the generated trigger signal, and the input of position 2 is 0;The controlled end of controlled switch receives additional control signal generated by logic control and protection moduleCtrl When the additional control signal Ctrl is "1", the trigger signal generated by the pulse generator is outputted, when the additional signal Ctrl Ctrl is "0", the additional control output duty cycle is 0; the unloading circuit control signal is obtained.

[0029] The drive output module is a drive amplification unit, which amplifies the trigger pulse outputted by the voltage regulation and pulse generation module, drives the insulated gate bipolar transistor (IGBT) device of the unloading circuit, and controls the on-off of the unloading resistor.

[0030] When the power supply is in a normal power supply operation state, the additional control link is locked; when the load is cut off, the additional control link is put into operation, and according to the power deviation of the converter on both sides , the duty cycle , , is calculated by proportional integral operation, which are proportional coefficient and integral coefficient respectively. When the difference between the current and on both sides of the converter is less than the set value, the additional control is restored, and the power supply is restored to the normal control strategy.

[0031] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor according to the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment on the basis of the prior art according to the concept of the present application shall be within the protection scope defined by the claims.

Claims

1. A power supply auxiliary control system, characterized in that, The system is equipped with an unloading circuit, a signal acquisition circuit, and an unloading circuit control circuit on the DC bus side of the power load-side converter; wherein, the unloading circuit control circuit includes: The logic control and protection module has an input terminal connected to a signal acquisition circuit, including a subtractor and a hysteresis comparator connected together, as well as a differentiator and a falling edge trigger delay connected together. The output terminal of the falling edge trigger delay is connected to the enable terminal of the hysteresis comparator. The control pulse generation module has an input terminal connected to a signal acquisition circuit and includes a subtractor, a proportional-integral controller, a pulse generator, and a controlled switch connected in sequence. The controlled terminal of the controlled switch is connected to the output terminal of a hysteresis comparator.

2. The power supply auxiliary control system according to claim 1, characterized in that, The unloading circuit includes at least a thyristor, the positive terminal of which is connected to the positive terminal of the DC bus.

3. The power supply auxiliary control system according to claim 1, characterized in that, The signal acquisition circuit includes current transformers and voltage transformers installed on the load side and the DC bus side.

4. The power supply auxiliary control system according to claim 1, characterized in that, The logic control and protection module includes: a subtractor, a hysteresis comparator, a differentiating circuit, and a falling edge triggered delay.

5. A power supply auxiliary control system according to claim 4, characterized in that, The aforementioned The input of the subtractor is connected to a signal acquisition circuit, and the output is connected to a hysteresis comparator. The input terminal of the differentiating circuit is connected to the signal acquisition circuit, the output terminal of the differentiating circuit is connected to the falling edge triggered delay, and the output terminal of the falling edge triggered delay is connected to the enable terminal of the hysteresis comparator.

6. A power supply auxiliary control system according to claim 5, characterized in that, The input terminal of the subtractor is connected to the signal acquisition circuit, the output terminal of the subtractor is connected to the output terminal of the proportional-integral controller, the output terminal of the proportional-integral controller is input to one end of the controlled switch, and the controlled terminal of the controlled switch is connected to the output terminal of the hysteresis comparator.

7. The power supply auxiliary control system according to claim 1, characterized in that, The additional control system further includes a drive output module, which is a drive amplification unit. Its input terminal is connected to the output of the control pulse generation module, and its output terminal is connected to the unloading circuit.

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