A circuit for obtaining a balanced control deviation

Abstract

The present invention provides a balanced control deviation acquisition circuit, comprising a resistor R1, an operational amplifier A1, a differential amplifier A2, and a connection terminal J. The present invention only requires a single coaxial line (or twisted pair) to obtain the average value #imgabs0# and the deviation Δv i =V avg ‑v i . Where: v i is the output of the unit with serial number i in the distributed system. Compared with the existing communication bus to obtain the deviation, the present invention only needs a few common components and wire connections to achieve the acquisition of the average value and deviation of the output of the distributed system balanced control, and has the characteristics of simple structure, low cost and good practicality.

Description

Technical Field

[0001] The present invention specifically relates to a circuit for acquiring a balance control deviation. Background Art

[0002] In the field of power electronics, in order to meet the requirements of voltage stress, current stress, redundancy, scalability and reliability, it is necessary to connect modules in series or (and) in parallel to reduce module voltage and current stress, and improve system load capacity, reliability and redundancy. Although multi-module cascading has a series of advantages such as redundancy, reliability and cost-effectiveness, there is a very common problem in module cascading - the problem of balanced control.

[0003] Due to the inconsistency of the characteristics of each module and the impedance of the connecting line, the module input or (and) output is unbalanced. Long-term operation in an unbalanced state will greatly reduce the module life and system reliability, causing failures, so the system must be balanced controlled. In order to achieve output balance control, the acquisition of the balance control deviation is a prerequisite.

[0004] The existing balanced control deviation acquisition is mainly realized by the communication bus, which has the following shortcomings: ① communication modules and related interface circuits are required, which increases the complexity and cost of the system hardware circuit; ② a dedicated communication protocol needs to be designed to process data, which increases the difficulty of system software development and reduces the response speed of the system. Therefore, a deviation acquisition circuit with simple structure, low cost and good practicality is needed. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a circuit for obtaining a balance control deviation.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A balanced control deviation acquisition circuit includes a busbar electrically connected to a plurality of electrical devices and a plurality of deviation acquisition circuits corresponding to the electrical devices, wherein the deviation acquisition circuit includes an average value circuit and a deviation calculation circuit for calculating a deviation according to an average value obtained by the average value circuit.

[0008] The average value circuit includes an operational amplifier A1, the in-phase input terminal of the operational amplifier A1 is connected to the voltage v of the electrical device through a resistor R1. i The output end is connected, the non-inverting input end of the operational amplifier A1 is connected to a terminal of the bus, and the non-inverting input end of the operational amplifier A1 is connected to the potential obtained by the bus The inverting input terminal of the operational amplifier A1 is connected to the output terminal of the operational amplifier A1, and the output terminal of the operational amplifier A1 outputs the mean value

[0009] The deviation calculation circuit includes a differential amplifier A2, the non-inverting input terminal of the differential amplifier A2 is connected to the output terminal of the operational amplifier A1, and the potential of the non-inverting input terminal of the differential amplifier A2 is The inverting input terminal of the differential amplifier A2 is connected to the voltage v i The output end of the differential amplifier A2 outputs the deviation Δv corresponding to the electrical device. i =V avg -v i .

[0010] The gain factor of the differential amplifier is 1.

[0011] The busbar is provided with a connection terminal at a connection position corresponding to each electrical device, and the connection terminal is connected to the deviation acquisition circuit.

[0012] The beneficial effects of the present invention are as follows: only a few common components and wire connections are needed to realize the acquisition of the deviation of the balanced control, and no communication bus is required to realize the acquisition of the deviation based on the average value balanced control. It has a simple structure, low cost and good practicality, and provides a new solution for balanced control. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The circuit diagram for obtaining the balance control deviation of the present invention. DETAILED DESCRIPTION

[0014] Without loss of generality, the present invention uses the i-th (1≤i≤n) deviation acquisition circuit as the object of explanation. The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Figure 1 The figure shows a circuit diagram for obtaining the deviation of the balance control. n circuits are connected to all the terminals J through coaxial cables or twisted pairs. Each deviation obtaining circuit includes: a resistor R1, an operational amplifier A1, a differential amplifier A2 and a terminal J. The connection method of the above electronic components is shown in the figure.

[0016] The present invention provides a balanced control deviation acquisition circuit, which includes a busbar electrically connected to a plurality of electrical devices and a plurality of deviation acquisition circuits arranged corresponding to the electrical devices. The deviation acquisition circuit includes an average value circuit and a deviation calculation circuit for calculating the deviation according to the average value obtained by the average value circuit.

[0017] The average value circuit includes an operational amplifier A1, the in-phase input terminal of the operational amplifier A1 is connected to the voltage v of the electrical device through a resistor R1. i The output end is connected, the non-inverting input end of the operational amplifier A1 is connected to a terminal of the bus, and the non-inverting input end of the operational amplifier A1 is connected to the potential obtained by the bus The inverting input terminal of the operational amplifier A1 is connected to the output terminal of the operational amplifier A1, and the output terminal of the operational amplifier A1 outputs the mean value The operational amplifier A1 is used to perform mean value calculation to obtain the mean value of the potential of several electrical devices.

[0018] The deviation calculation circuit includes a differential amplifier A2, the non-inverting input terminal of the differential amplifier A2 is connected to the output terminal of the operational amplifier A1, and the potential of the non-inverting input terminal of the differential amplifier A2 is The inverting input terminal of the differential amplifier A2 is connected to the voltage v i The output end of the differential amplifier A2 outputs the deviation Δv corresponding to the electrical device. i =V avg -v i .

[0019] The gain factor of the differential amplifier is 1.

[0020] The busbar is a coaxial line or a twisted pair, and a connection terminal is provided at the connection point of each electrical device corresponding to the busbar, and the connection terminal is connected to the deviation acquisition circuit. Each electrical device is electrically connected through the busbar, and the electrical parameters of each electrical device are obtained through the connection terminals respectively connected to the corresponding electrical devices.

[0021] The variables are described as follows: i It is a voltage signal with the same value as the physical quantity to be balanced and controlled. is the potential of the non-inverting input terminal of operational amplifier A1, is the potential of the non-inverting input terminal of differential amplifier A2, V avg v i (1≤i≤n), Δv i is the deviation amount.

[0022] The potential of the in-phase terminal of all deviation acquisition circuits A1 is the same, so:

[0023]

[0024] make: According to Kirchhoff's current law, we can get:

[0025]

[0026] because Arranging (2) yields:

[0027] v A1+ =V avg (3)

[0028] Since A1 satisfies the "virtual short" condition, we have:

[0029]

[0030] Let: the gain of differential amplifier A2 is 1, then:

[0031] Δv i =V avg -v i (5)

[0032] It can be seen from formula (5) that the output of A2 is the deviation, so the deviation of the balanced control can be calculated by sampling the voltage at the output end of A2.

[0033] The embodiments should not be regarded as limiting the present invention, but any improvements made based on the spirit of the present invention should be within the protection scope of the present invention.

Claims

1. A circuit for obtaining an average value and a deviation of a balanced control, characterized in that: The utility model comprises a busbar electrically connected to a plurality of electrical devices and a plurality of deviation acquisition circuits corresponding to the electrical devices, wherein the deviation acquisition circuit comprises an average value circuit and a deviation calculation circuit for obtaining the deviation according to the average value obtained by the average value circuit, and the average value circuit comprises an operational amplifier A1, and the in-phase input terminal of the operational amplifier A1 is connected to the voltage of the electrical device through a resistor R1. The output end is connected, the non-inverting input end of the operational amplifier A1 is connected to a terminal of the bus, and the non-inverting input end of the operational amplifier A1 is connected to a potential obtained by the bus , The inverting input terminal of the operational amplifier A1 is connected to the output terminal of the operational amplifier A1, and the output terminal of the operational amplifier A1 outputs the mean value The deviation calculation circuit includes a differential amplifier A2, the non-inverting input terminal of the differential amplifier A2 is connected to the output terminal of the operational amplifier A1, and the potential of the non-inverting input terminal of the differential amplifier A2 is , , the inverting input terminal of the differential amplifier A2 is connected to the voltage of the electrical device The output terminal of the differential amplifier A2 outputs the deviation of the corresponding electrical device. The busbar is provided with a connection terminal at a connection point corresponding to each electrical device, and the connection terminal is connected to the deviation acquisition circuit.

2. The circuit for obtaining the average value and deviation of equalization control according to claim 1, characterized in that: The gain factor of the differential amplifier is 1.

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