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<span title="关于开关电源的斜坡补偿问题，技术人员经常可以遇到，但是非专业的基本上不接触的，本文意在让用户对这种问题有所了解。">About switching power supply ramp compensation issues, technical personnel can often be encountered, but essentially non-professional contact, this article is intended to allow the user to understand this problem.<br />
</span><span title="斜坡补偿的定义：在电流模式控制下，当电流达到一定大小时（由误差放大器输出设定）开关关断。">Slope compensation definition: In current mode control, when the current reaches a certain size (set by the error amplifier output) switch off. </span><span title="如果占空比超过50%，电感电流的上升时间就大于整个周期的50%，起因：当电流模式控制变换器的占空比超过50%的时候，变换器会在开关频率的次谐波频率">If the duty cycle exceeds 50%, the rise time of the inductor current is greater than 50% of the whole cycle, cause: when the current mode control duty cycle exceeds 50% of the converter when the inverter switching frequency in the harmonic frequencies </span><span title="点出现振荡，准确地说是在一半开关频率的地方，除非采取斜坡补偿措施。">point oscillation occurs, precisely half the switching frequency in place, unless you take the slope compensation measures.<br />
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</span><span title="以下原因,峰值电流控制必须考虑采用斜坡补偿。">For the following reasons, the peak current control slope compensation must be considered.<br />
</span><span title="电路的稳定性、减小尖峰值/平均值误差、抑制次谐波振荡、振铃电感电流那么电流下降时间就小于一个周期的50%'。">Stability of the circuit, reducing the peak value / average error suppression harmonic oscillations, ringing the inductor current then the current fall time is less than 50% of a cycle. ' </span><span title="在较短的时间内，电流还没有来得及回到静态初始值，下一个周期接着又开始了。">In the short period of time, the current has not had time to return to the static initial value, then the next cycle began again. </span><span title="下一个周期的初始电流变大了。">The next cycle of the initial current larger. </span><span title="在接下来的这个周期里，电感电流很快就上升到参考点，使导通时间变短，占空比变得更窄；和上一个周期相比，这个周期的占空比减小到50">In this next cycle, the inductor current is quickly increased to the reference point, the on-time becomes short, the duty cycle becomes narrower; compared to the previous one cycle, the duty cycle is reduced to 50 </span><span title="%以内。">% or less. </span><span title="但是这样又导致关断时间太长，下一个周期电流的初始值太小，又使得占空比再一次超过50%。">But this has led to the off-time is too long, the next cycle of the initial current value is too small, but also makes more than 50% duty cycle once again. </span><span title="如此循环，电流以间隔一个周期过大和过小的方式出现振荡。">This cycle, the current cycle over an interval of a Japanese way too small oscillation occurs.<br />
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</span><span title="操作：针对这个问题，斜坡补偿基本上是在电流上迭加一个固定斜坡的信号。">Operation: For this problem, the slope compensation basically a fixed ramp superimposed on the current signal. </span><span title="由于所迭加的斜坡是一个固定值，电流闭环的影响可以得到较好抑制。">Since the slope of superposition is a fixed value, the impact of the current loop can be better suppressed. </span><span title="事实上，斜坡补偿的真正作用是使控制环更像电压模式控制。">In fact, the true role of slope compensation is more like the control loop voltage mode control. </span><span title="可以这样来理解：电压模式控制是用固定斜坡的锯齿波和误差放大器的输出进行比较，所以当选加的斜坡越来越大的时候，变换器就越来越像电压模式控制，当斜坡补偿的">Can be understood: voltage-mode control with fixed slope ramp and the output of the error amplifier compares the slopes so elected plus more and more time, more and more like the converter voltage mode control, when the slope compensation </span><span title="幅度与电流信号幅度之比趋于无穷大时，就完全变成了电压模式控制。">the magnitude of the current signal amplitude ratio tends to infinity, it turned into a voltage mode control. </span><span title="刚才的说法也同样可以得到解释：电源轻载时电流模式控制就变成了电压模式控制。">I just said they can also be explained: The power light load current mode control becomes a voltage mode control.</span></p>
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