A New Symmetrical Power Filter Network Structure and Its Parameter Design Method

Abstract

The invention discloses a novel symmetric power filter network structure which comprises a pair of inductors L1, a first capacitor C1, a resistor R1, a pair of second capacitors C2 and a third capacitor C3, wherein input ends of the inductors L1 are respectively connected with a pair of output ends of a PWM (Pulse-Width Modulation) driving system; the inductors L1 are used for determining a system bandwidth; the first capacitor C1 is used for regulating system damping to prevent resonance; one end of the first capacitor C1 is connected with an output end of one inductor L1; the resistor R1 is used for regulating the system damping to prevent resonance; one end of the resistor R1 is connected with the other end of the first capacitor C1, and the other end of the resistor R1 is connected with an output end of the other inductor L1; the pair of second capacitors C2 are used for establishing system reference ground to adsorb high-frequency noise; the pair of second capacitor C2 is connected in series to form a series circuit, and a series point is grounded; both ends of the series circuit are respectively connected with the output ends of the pair of inductors L1; and both ends of the third capacitor C3 are respectively connected with the output ends of the pair of inductors L1 and a pair of input ends of a motor load. The novel symmetric power filter network structure has the advantages that the symmetric filter network can be equivalent to a second-order filter, and is easy in parameter design; and rapid design can be implemented.

Description

technical field [0001] The invention relates to the technical field of miniature digital servo systems, in particular to a novel symmetrical power filter network structure and a parameter design method thereof. Background technique [0002] Miniaturization is an inevitable trend in the development of servo controllers. Traditional analog servo controllers have been widely used for their high stability. With the continuous improvement of servo control system performance indicators, analog control strategies can no longer meet the precision requirements. Requirements, first of all, it is not conducive to the application of advanced control algorithms, and the size and power consumption of analog components are large, which cannot meet the needs of miniaturization of servo controllers. Based on the above reasons, digital control has become an inevitable trend. [0003] In the digital control system, the pulse width modulation (PWM) driving method has been widely used for its ad...

AI Technical Summary

Problems solved by technology

The patent "A three-phase PWM rectifier three-loop control method with LCL filter" (201110327903.7) proposes an LCL filter, but the application of this filter is a three-phase PWM rectifier, and the power consumption is relatively high

The patent "LC filter based on PWM inverter" (201320709945.1) proposes a multi-stage filter in the form of LC with a relatively complex structure

In the article "Filtering and Control of High Speed ​​Motor Currentin a Flywheel Energy Storage System", scholars from the Glenn Research Institute in the United States proposed a multi-stage filter design scheme, using a multi-stage LCR filter with split inductance method, such as figure 2 As shown, the structure of this scheme is complicated. Although it can obtain a certain suppression effect, its power consumption and size are too large, which does not meet the requirements of miniaturization, and also increases the difficulty of design.

Professor Li Haixia from Tsinghua University proposed a simplified filter network in the article "Design of Low-noise PWM Power Drive Device for High-precision Inertial Navigation Platform", but in practice, the power consumption is relatively large, and the suppression effect on high-frequency noise is poor.

[0011] To sum up, the filters involved in the current bipolar PWM drive system have the disadvantages of complex structure, difficult design, high cost and large size, and cannot be used in a small space, which is not conducive to the development trend of miniaturization of servo controllers.

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