Composite feedforward control type hysteresis control system

Abstract

The invention relates to a composite feedforward control type hysteresis control system. The composite feedforward control type hysteresis control system comprises input voltage Vi, a main switch tube, a filter circuit and a load Ro all of which are sequentially connected. The main switch tube is connected with a driving circuit. The composite feedforward control type hysteresis control system further comprises a feedback bypass, an adjusting capacitor C, a hysteresis comparison circuit and a feedforward circuit. The feedback bypass is respectively connected with the main switch tube and the load Ro, the adjusting capacitor C is connected with the feedback bypass, the input end of the hysteresis comparison circuit is respectively connected with the adjusting capacitor C, the feedforward circuit and the main switch tube, the output end of the hysteresis comparison circuit is connected with the driving circuit, and the feedforward circuit is connected with the input voltage Vi. Compared with the prior art, the composite feedforward control type hysteresis control system has the advantages of being good in dynamic characteristic, simple in control circuit topology, low in cost, high in efficiency and the like.

Description

technical field [0001] The invention relates to PWM voltage control technology, in particular to a compound feedforward control type hysteresis control system. Background technique [0002] With the rapid development of information technology, the output voltage of the power supply VRM (voltage regulating module) that provides the working voltage of the microprocessor is getting lower and lower, and the output current is getting larger and larger, and the fluctuation of the power supply voltage is required during dynamic changes It must be suppressed in a very small range, which puts forward higher requirements on the dynamic performance of VRM. Usually, the most basic control method of VRM is PWM voltage control, which is a single-loop control strategy with simple working principle and algorithm. However, due to the limitation of bandwidth, its anti-input voltage disturbance capability and dynamic load performance are relatively poor, especially the dynamic response effect...

AI Technical Summary

Problems solved by technology

[0004] 1. In the traditional PWM voltage control method, operational amplifiers, triangular carrier generation circuits and other compensation circuits must be used, which will easily lead to an increase in the manufacturing cost of the DC-DC converter, and it is difficult to achieve miniaturization and light weight

[0005] 2. The error characteristics of the operational amplifier will seriously affect the performance of the control circuit

In this way, the designer must spend a lot of time, manpower and material resources when solving the stability problem of the operational amplifier.

[0006] 3. In the traditional PWM voltage control method, adjusting the phase compensation circuit is to improve the load variation characteristics through the gain and bandwidth of the error amplifier, but this method requires skilled power supply design technology and is not easy to do

[0007] 4. The traditional PWM voltage control is based on the precise mathematical model of the system, which is highly dependent on the model. When the system parameters change greatly, the control effect will deteriorate, and even lose the adjustment function in severe cases.

In practical applications, when a well-tuned parameter controller is applied to a time-varying system with model parameters, the performance of the system will become poor or even unstable

In addition, in the process of parameter tuning, the parameter setting value is an optimal value with a certain locality, rather than a global optimal value, so this control function cannot fundamentally solve the problem of dynamic quality and steady-state accuracy. contradiction

[0008] In view of the above reasons, the traditional PWM voltage control method is difficult to meet the technical indicators of input and output high-speed transient response, miniaturization, light weight, low cost, and high efficiency

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