CN104123951A - 具有改进的起转控制的磁盘驱动器 - Google Patents
具有改进的起转控制的磁盘驱动器 Download PDFInfo
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- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
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- G—PHYSICS
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- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
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Abstract
公开的一种磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动磁盘的主轴电机。该主轴电机在主轴电机的单次运转中按照多个电周期操作,其中每个电周期跨越一周期段。多个周期段被测量,至少两个周期段被合并,并且基于合并的周期段测量主轴电机的转速。
Description
背景技术
磁盘驱动器包括磁盘和与驱动器臂的远端连接的磁头,音圈电机(VCM)使驱动器臂围绕枢轴转动以将磁头径向地放置在磁盘上方。磁盘包括用于记录用户数据扇区和伺服扇区的多个径向间隔的同心磁道。伺服扇区包括由磁头读取并由伺服控制系统处理的磁头定位信息(例如,磁道地址),以控制致动器臂在磁道间的搜索。
主轴电机高速转动磁盘(一个或更多个)以使磁头基本上飞越空气轴承上的磁盘表面。当磁盘驱动器上电时,执行起转操作从而在将磁头加载到磁盘表面之前将磁盘起转到运行速度。为了最小化主机可存取磁盘驱动器之前的延迟,期望尽可能快地起转磁盘。并且,可以期望在一组磁盘驱动器间获得大体一致的起转时间,从而磁盘驱动器制造商可以提供准确的起转时间规格,从而能够根据起转规格设计存储系统
附图说明
图1A和1B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图1C为根据一个实施例的流程图,其中测量主轴电机的多个电周期段,合并至少两个周期段,并基于合并的周期段测量主轴电机的转速。
图1D示出了一个实施例,其中使用对主轴电机的N个连续电周期段进行平均的滑动平均滤波器来合并周期段。
图2A和2B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图2C为根据一个实施例的流程图,其中产生作为所测量的主轴电机转速的函数的起转增益,其中该函数包括次数大于1的多项式。
图2D示出了根据一个实施例的基于起转增益起转主轴电机的控制电路。
图2E示出了根据一个实施例的用于产生起转增益的次数大于1的多项式,其中起转增益作为所测量的主轴电机转速的函数。
图3A和3B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图3C为根据一个实施例的流程图,其中基于所测量的主轴电机转速产生前馈起转控制。
图3D示出了根据一个实施例的基于前馈起转控制起转主轴电机的控制电路。
图4A和4B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图4C为根据一个实施例的流程图,其中基于速度命令简档起转主轴电机,速度命令简档保证在最坏情形的环境条件下的最小起转时间和有限的功耗。
图4D根据一个实施例示出了基于速度命令简档起转主轴电机的控制电路。
图4E根据一个实施例示出了速度命令简档的示例。
图5A和5B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图5C为根据一个实施例的流程图,其中基于初始测量的主轴电机转速在起转时间的第二部分上起转主轴电机。
图5D根据一个实施例示出了用于在起转时间的第二部分上起转主轴电机的控制电路。
图5E根据一个实施例示出了如何根据初始测量的主轴电机转速可以确定起转时间的第二部分。
图6A和6B示出了根据一个实施例的磁盘驱动器,其包括在磁盘上方被致动的磁头和转动磁盘的主轴电机。
图6C为根据一个实施例的流程图,其中,在起转主轴电机之后,基于起转控制器的状态初始化定速控制器的积分器。
图6D根据一个实施例示出了使用起转控制器起转主轴电机的控制电路。
图6E根据一个实施例示出了在完成起转操作之后,使用定速控制器旋转磁盘的控制电路。
图7根据一个实施例示出了使用如上描述的方法的组合起转主轴电机的控制电路。
具体实施方式
图1A和1B示出了根据一个实施例的磁盘驱动器,其包括在磁盘4上方被致动的磁头2A和可操作以转动磁盘4的主轴电机6。在主轴电机6的单次运转中,主轴电机6按照多个电周期进行操作,其中每个电周期跨一周期段。磁盘驱动器进一步包括控制电路8,其可操作以执行图1C中的流程图,其中,测量多个周期段(块10),合并至少两个周期段(块12),以及基于合并的周期段测量主轴电机的转速(块14)。
在图1B的实施例中,磁盘表面4A包括多个由伺服扇区180-18N限定的伺服磁道16,其中数据磁道相对于伺服磁道以相同或不同的径向密度而限定。控制电路8处理从磁头2A发出的读信号以解调伺服扇区180-18N并产生表示磁头的实际位置和相对于目标磁道的目标位置之间的误差的位置误差信号(PES)。控制电路8使用合适的补偿滤波器对PES进行滤波以产生施加到音圈电机(VCM)22上的控制信号20,其中音圈电机使致动器臂围绕枢轴转动,从而使得磁头2A在磁盘表面4A上以减小PES的方向径向转动。伺服扇区180-18N可以包括任意合适的磁头位置信息,例如,用于粗定位的磁道地址和用于精细定位的伺服脉冲。伺服脉冲可以包括任意合适的图形,例如,基于幅度的伺服图形或基于相位的伺服图形。
在起转操作过程中,控制电路8测量主轴电机6的转速,其与速度命令简档的目标转速进行比较。基于差值(误差)产生控制信号24以使主轴电机的转速基本上跟随速度命令简档直到达到起转转速。起转操作的性能可以取决于所测量的主轴电机的转速的准确性。
在一个实施例中,主轴电机的转速可以通过评估主轴电机的每个绕组中的反电动势(BEMF)过零点来测量。在单次运转中,主轴电机通常按照多个电周期操作,其中电周期的总数目取决于主轴电机的所采用的极对的数目。例如,6极对的主轴电机在单次运转中将产生6个电周期。因此,在表示电周期结束的每个BEMF过零点处,主轴电机的转速可表示为:
然而,由于极点未对准,基于单个电周期测量主轴电机的转速会产生有噪声的测量,从而降低起转操作的性能。因此,在一个实施例中,通过合并至少两个周期段,然后基于合并的周期段测量主轴电机的转速,减小了由于极点未对准引起的噪声。
图1D示出了根据一个实施例的控制电路,其中主轴电机在单次主轴电机运转中按照N个电周期操作,并通过对N个连续的周期段求和来合并周期段。块26测量主轴电机的电周期段28,例如,通过检测绕组产生的BEMF电压中的过零点。测量的电周期段28被转变到延迟线30中,并且在测量N个电周期段之后,产生作为最后的N个测量的电周期段28的总和的机械周期段32。机械周期段32在块34中被转换为每分钟旋转次数(RPM)的测量的转速36。测量的电周期段被累加38以产生索引速度命令简档(SCP)42的时间索引40,其中速度命令简档在起转间隙上输出目标转速44。目标转速44减去测量的转速36生成控制器48处理的误差信号46。控制器48产生施加到驱动器52上的控制信号50以产生施加到主轴电机6的控制信号24,从而加速主轴电机6,以使转速基本上跟随SCP42输出的目标速度。
在图1D的实施例中,随着每个新的电周期28在块26处被测量,机械周期段32基于运行中的N个连续的电周期段被更新。也就是说,延迟线30、加法器54和标量34实现以下形式的滑动平均滤波器(MAF):
以上公式表示的滑动平均滤波器有效地过滤掉由于极点未对追所导致的测量的主轴电机转速中的噪声。在一个实施例中,可修改上述滑动平均滤波器以在主轴电机运转中对少于或多于N个的电周期段求和。
图2A和2B示出了根据一个实施例的磁盘驱动器,其中控制电路8在起转操作期间可操作以执行图2C中的流程图。测量主轴电机的转速(块56),产生作为所测量的转速的函数的增益(块58),其中该函数包括次数大于1的多项式。基于该增益起转主轴电机(块60)。
图2D根据一个实施例示出了用于起转主轴电机的控制电路,其中块62测量主轴电机6的转速64,例如,如上所述的通过测量电周期段而测量。函数66产生用于起转主轴电机的增益Kfbk68,其中,在图2D的实施例中,增益Kfbk68乘以误差信号46产生控制信号50。也就是说,图2D的实施例中的控制电路至少包括用于起转主轴电机的比例控制器,其中该比例控制器的增益被产生以作为所测量的主轴控制器的转速的函数。
图2E描述了一个实施例,其中用于产生图2D中的增益Kfbk的函数66包括次数大于1的多项式。在图2D的示例中,函数66包括二次多项式;然而,其他实施例可以采用更高次的多项式。在一个实施例中,可针对若干不同的转速基于控制环路的设计带宽使用复杂方程计算增益Kfbk,该复杂方程包括主轴电机6、电机驱动器52的传输函数和测量主轴电机转速的函数(例如,上述的MAF)。在生成用于若干不同转速的增益Kfbk之后,增益值可被拟合为表示次数大于1的多项式的曲线。下面是基于测量的转速和控制环路的带宽导出增益Kfbk的示例:
定义单位:
kRPM:=1000RPM gmf:=10-3kgf
电机参数:
惯性:=44gm·cm2=4.4×10-6m2·kg
Rw:=3.6Ω Ri:=0.124Ω Rd:=0.648Ω
Lw:=0.6mH Ra:=Rw+Ri+Rd=4.372Ω
速度0:=5400RPM
周期:=6
SpClockFreq:=100MHz SpClockDiv:=32
Vsup ply:=5V nBitsKval:=12
裕量LT:=0.8裕量Ke:=0.9
基本计算:
电极点:
等效阻抗:
机械极点:
电机传输函数:
滑动平均滤波器:
开环传输函数:
PI控制器系数:folbw=11.25Hz,
在以上示例中,对于5400RPM的测量的转速,已经计算的增益为Kfbk=25.457。下面的表格显示了针对不同的测量的主轴电机的转速,使用上述推导计算的增益Kfdk。然后,表格中的增益Kfdk值可以被拟合为由如下多项式表示的曲线:
y=0.0041x2+0.5814x+0.924
主轴速度(RPM) | 采样频率(Hz) | 开环带宽(Hz) | Kfbk |
300 | 30 | 0.63 | 1.743 |
400 | 40 | 0.83 | 2.081 |
500 | 50 | 1.04 | 2.448 |
750 | 75 | 1.56 | 3.38 |
1000 | 100 | 2.08 | 4.33 |
1500 | 150 | 3.13 | 6.304 |
1750 | 175 | 3.65 | 7.305 |
2000 | 200 | 4.17 | 8.326 |
2250 | 225 | 4.69 | 9.368 |
2500 | 250 | 5.21 | 10.435 |
3000 | 300 | 6.25 | 12.651 |
3500 | 350 | 7.29 | 14.995 |
4500 | 450 | 9.38 | 20.173 |
5400 | 540 | 11.25 | 25.457 |
图3A和3B示出了根据一个实施例的磁盘驱动器,其中控制电路8可操作以在起转操作期间执行图3C的流程图。测量主轴电机的转速(块70),以及基于测量的转速产生前馈控制(块72)。基于前馈控制起转主轴电机(块74)。
图3D根据一个实施例示出了用于起转主轴电机的控制电路,其中反馈控制器76基于误差信号46产生反馈控制信号78。反馈控制器76可以实现任意合适的反馈算法,例如图2D中的比例控制。反馈控制信号78由前馈控制信号80调整以产生被施加到驱动器52的控制信号50。前馈控制信号80可以补偿注入到控制环路中的一个或更多个干扰,例如主轴电机6的BEMF,或主轴电机6的阻力矩。
在一个实施例中,主轴电机6的BEMF抵消控制信号50的加速转矩,从而为了向主轴电机6施加期望的加速转矩,就需要更高的控制信号(例如,更高的驱动电流)。在一个实施例中,主轴电机6的BEMF随着主轴电机的转速Nm成比例地增加,因此在图3D所示的实施例中,通过将测量的转速64乘以表示主轴电机6的BEMF常数的增益Ke84而生成第一前馈控制信号82。在一个实施例中,主轴电机的BEMF常数根据环境温度而改变,因此在图2D的实施例中,增益Ke84基于测量的磁盘驱动器的环境温度T进行调整。
在一个实施例中,主轴电机6可以呈现抵消阻力矩的性能,其中的抵消阻力矩的性能还可以根据以下公式基于主轴电机6的转速而变化:
其中LT表示负载转矩,其为转速Nm和环境温度T的函数,Rw表示绕组阻抗,其为环境温度T的函数,并且Kt表示主轴电机的转矩常数,其为环境温度T的函数。因此,图3D的控制电路包括表示上述公式的块86和88,用于产生叠加到第一前馈控制信号82上以产生复合前馈控制信号80的第二前馈控制信号90。可以采用任何合适的函数计算负载转矩(LT),其作为转速Nm和环境温度T的函数,其中在一个实施例中,该函数可通过在若干不同环境温度上从主轴电机的典型子集获得的标称负载转矩测量值进行曲线拟合而产生。
图4A和4B示出了根据一个实施例的磁盘驱动器,其中控制电路8可操作以在起转操作期间执行图4C的流程图。测量主轴电机的转速(块92),并基于测量的转速和速度命令简档产生控制信号(块94)。基于该控制信号起转主轴电机(块96)。
图4D根据一个实施例示出了用于起转主轴电机的控制电路,其中,产生速度命令简档42以保证最坏情形的环境条件下的最小起转时间和有限的功耗。控制器98基于测量的主轴电机的转速64与速度命令简档42产生的目标转速之间的差值(误差信号46)产生控制信号50。图4E示出了包括目标速度的速度命令简档42的示例,该目标速度是起转时间的函数。速度命令简档可以以任何合适的方式产生,例如,在最坏情形的环境条件下(例如,最坏情形的环境温度),经验性评估主轴电机的典型子集。在另一个实施例中,速度命令简档可基于主轴电机的标称技术特征和最坏情形的环境条件下主轴电机的标称特征描述进行理论计算。在一个实施例中,速度命令简档可以说明主轴电机的最大电流消耗。通过考虑最坏情形的环境条件以及主轴电机的最大电流消耗,可以产生在所有运行条件下都保证最小(以及一致的)起转时间和有限功耗的速度命令简档42。
图5A和5B示出了根据一个实施例的磁盘驱动器,其中控制电路8可操作以在起转操作期间执行图5C的流程图。测量主轴电机的转速(块106),并基于测量的转速和目标转速之间的差值产生控制信号(块108)。基于所产生的控制信号在起转时间的第二部分上起转主轴电机(块110),其中基于速度命令简档和起转时间的第二部分产生目标转速。在产生控制信号之前,基于初始测量的主轴电机的转速确定起转时间的第二部分(块104)。
在图5C的实施例中,控制电路8在起转时间的第一部分使用开环控制系统开始起转主轴电机(块100)。在起转时间的第一部分之后,测量主轴电机的初始转速(块102)以便可以确定起转时间的第二部分(块104)。在图5E所示的速度命令简档所描述的一个实施例中,主轴电机在起转时间内以随着时间渐增的相应的目标速度起转。在起转时间的第一部分期间,主轴电机被开环控制(独立于控制信号50),其中,在该时间结束时,主轴电机将以未知转速进行转动。在使能图5D的闭环控制电路之前,测量主轴电机的初始转速从而可以确定图5E的速度命令简档上的相应点,并且可以适当地初始化时间索引40。
在图5E所示的实施例中,向初始测量的转速增加一增量(delta)从而在使能图5D的闭环控制电路时初始目标转速高于初始测量的转速。通过这种方式,在使能图5D的控制电路之后,初始目标转速保证主轴电机从初始测量的转速继续加速。在增加增量以产生初始目标转速后,可以确定速度命令简档中相应的时间。图5D中的时间38可被初始化为零,并且偏移量112被加到时间38上,其基于初始测量的主轴电机的转速114。再次参考图5E,将偏移量112加到时间38上后,然后速度命令简档产生起转时间的第二部分上的目标转速,其中基于该目标转速产生图5D的闭环控制电路中的控制信号50。
图6A和6B示出了根据一个实施例的磁盘驱动器,其中控制电路8可操作以在起转操作期间执行图6C的流程图。使用起转控制器将主轴电机起转到目标转速(块116)。在起转主轴电机后,基于起转控制器的状态初始化积分器(块118),然后使用包括该积分器的定速控制器控制主轴电机(块120)。
图6D示出了包括起转控制器122的控制电路,其可操作以使用,例如,上述一种或更多种技术起转主轴电机6。图6E示出了根据一个实施例的控制电路,其中,在起转操作结束时,使用定速控制器124控制主轴电机6的速度。在图6E的实施例中,定速控制器124包括比例/积分(PI)控制器,其包括用于与误差信号46相乘的成比例的增益Kp126和用于对误差信号46进行积分的积分器128。误差信号46可以被产生作为主轴电机6的测量的转速64和与磁盘驱动器正常操作期间的恒定转速对应的目标速度130之间的差值。
在一个实施例中,当控制电路8从图6D所示的起转控制器122转变为图6E所示的定速控制器124时,为了最小化任何下冲或过冲,基于起转控制器122的状态初始化定速控制器124的积分器128。在一个实施例中,当速度命令简档最后达到最终目标速度(在起转间隔结束时),并且误差信号46以慢速变化,保证起转控制器122已经达到稳定状态时,控制电路8将从起转控制器122转变为定速控制器124。因此,当起转控制器122达到稳定状态时,由起转控制器122产生的加速控制信号50成为用于定速控制器124的积分器128的初始状态的良好候选。在一个实施例中,控制电路可操作以根据以下公式初始化积分器128:
Accel-Kp·SpeedErr
其中Accel表示在起转操作结束时起转控制器122的加速控制信号50,Kp表示定速控制器124的增益126,并且SpeedErr表示误差信号46。
图7根据一个实施例示出了控制电路,其可操作以使用上述方法的组合起转主轴电机6。然而,其他实施例可采用更少的上述技术,或结合上述技术中一种或更多种的不同技术。例如,在一些实施例中,如果存在极点的轻微未对准,则为了测量主轴电机6的转速36,可以不必采用滑动平均滤波器。其他实施例可以通过使用或不使用上述技术中的一种或更多种,采用滑动平均滤波器测量转速36。
可采用任意合适的控制电路来实现上述实施例中的流程图,例如任意合适的集成电路(一个或更多个)。举例来说,控制电路可以在功率集成电路(PIC)中,或者在与PIC分离的组件例如磁盘控制器中实现,或者上述某些操作可以由PIC执行而其他操作由磁盘控制器执行。在一个实施例中,PIC和磁盘控制器被实现为分离的集成电路,但在一个替代实施例中,它们可以被制造在单个集成电路或片上系统(SOC)中。
在一个实施例中,控制电路包括执行指令的微处理器,这些指令可操作以使微处理器执行在此描述的流程图。指令可以存储在任意计算机可读介质中。在一个实施例中,它们可存储在位于微处理器外部或与SOC中的微处理器集成的非易失半导体存储器中。在另一个实施例中,指令存储在磁盘上并且当磁盘驱动器上电时其被读入到易失生半导体存储器中。在又一个实施例中,控制电路包括合适的逻辑电路,例如状态机电路。
上述各种特征和过程可以彼此独立使用,或者以各种方式组合。所有可能的组合以及子组合都落入本公开的范围内。此外,在一些实现方式中某些方法、事件或过程块可省略。在此描述的方法和过程也并不局限于任意特定的顺序,并且与其相关的块或状态能够以其他合适的顺序执行。例如,所述任务或事件可以以不同于所具体公开的顺序执行,或者多个可被组合在单个块或状态中。示例任务或事件可以以串行、并行或其他一些方式执行。任务或事件可以加到所公开的示例实施例中,或者将其从所公开的示例性实施例中移除。在此描述的示例系统和组件可以以不同于所描述的方式配置。例如,与所公开的示例实施例相比,可以增加、移除或重新设置元件。
尽管已经描述了一些示例实施例,但这些实施例仅以举例方式呈现,并非意在限制所公开的本发明的范围。因此,前面的描述并非意在暗示任何具体的特征、特性、步骤、模块或块是必需或不可缺少的。实际上,在此描述的新颖方法和系统可以以各种其他形式实施;进一步地,可以以在此描述的方法和系统的形式进行各种省略、替换和改变,而不背离此处所公开的本发明的精神。
Claims (44)
1.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动所述磁盘的主轴电机,其中:
所述主轴电机在所述主轴电机的单次运转中按照多个电周期操作;并且
每个电周期跨越一周期段;和
控制电路,其可操作以:
测量多个所述周期段;
合并至少两个所述周期段;以及
基于所合并的周期段测量所述主轴电机的转速。
2.如权利要求1所述的磁盘驱动器,其中所述主轴电机在单次运转中按照N个电周期操作,并且所述控制电路进一步可操作以通过对N个连续周期段求和,从而产生所述合并的周期段。
3.如权利要求1所述的磁盘驱动器,其中所述控制电路进一步可操作以:
随着每个新的周期段被测量,通过对运行的N个连续周期段求和而更新所述合并的周期段;以及
基于所更新后的合并的周期段而更新所测量的转速。
4.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动所述磁盘的主轴电机;和
控制电路,其可操作以:
测量所述主轴电机的转速;
产生作为所测量的转速的函数的增益,其中所述函数包括次数大于1的多项式;以及
基于所述增益起转所述主轴电机。
5.如权利要求4所述的磁盘驱动器,其中所述增益包括可操作以放大反馈误差信号的反馈增益。
6.如权利要求5所述的磁盘驱动器,其中所述反馈误差信号表示所述测量的转速和目标转速之间的差值。
7.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动磁盘的主轴电机;和
控制电路,其可操作以:
测量所述主轴电机的转速;
基于所测量的转速产生前馈控制;以及
基于所述前馈控制起转所述主轴电机。
8.如权利要求7所述的磁盘驱动器,其中所述控制电路可操作以基于所述测量的转速和所述磁盘驱动器的环境温度而产生所述前馈控制。
9.如权利要求7所述的磁盘驱动器,其中所述控制电路可操作以产生与所述测量的转速成比例的所述前馈控制。
10.如权利要求9所述的磁盘驱动器,其中所述前馈控制补偿所述主轴电机的反电动势。
11.如权利要求7所述的磁盘驱动器,其中所述前馈控制补偿所述主轴电机的阻力矩。
12.如权利要求11所述的磁盘驱动器,其中所述控制电路可操作以基于所述测量的转速和所述磁盘驱动器的环境温度而产生所述前馈控制。
13.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动所述磁盘的主轴电机;和
控制电路,其可操作以:
测量所述主轴电机的转速;
基于所测量的转速和速度命令简档产生控制信号;以及
基于所述控制信号起转所述主轴电机,其中所述速度命令简档保证在最坏情况的环境条件下的最小起转时间和有限的功耗。
14.如权利要求13所述的磁盘驱动器,其中所述环境条件包括所述磁盘驱动器的环境温度。
15.如权利要求13所述的磁盘驱动器,其中所述速度命令简档说明所述主轴电机的最大电流消耗。
16.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动所述磁盘的主轴电机;和
控制电路,其可操作以:
测量所述主轴电机的转速;
基于所测量的转速和目标转速之间的差值产生控制信号;以及
在起转时间的第二部分上基于所产生的所述控制信号起转所述主轴电机;
其中:
所述目标转速基于速度命令简档和所述起转时间的所述第二部分而产生;并且
所述控制电路可操作以在产生所述控制信号之前基于初始测量的所述主轴电机的转速而确定所述起转时间的所述第二部分。
17.如权利要求16所述的磁盘驱动器,其中所述控制电路可操作以初始化所述起转时间的所述第二部分从而使得初始目标转速大于所述初始测量的转速。
18.如权利要求17所述的磁盘驱动器,其中,当产生所述控制信号时,所述初始目标转速保证所述主轴电机从所述初始测量的转速继续加速。
19.如权利要求18所述的磁盘驱动器,其中所述控制电路进一步可操作以:
针对所述起转时间的第一部分,独立于所述控制信号开始控制所述主轴电机;以及
在所述起转时间的所述第一部分之后,针对所述起转时间的所述第二部分,基于所述控制信号控制所述主轴电机。
20.一种磁盘驱动器,包括:
在磁盘上方被致动的磁头;
可操作以转动所述磁盘的主轴电机;和
控制电路,其可操作以:
使用起转控制器将所述主轴电机起转到目标转速;
在起转所述主轴电机之后,基于所述起转控制器的状态初始化积分器;以及
使用包括所述积分器的定速控制器控制所述主轴电机。
21.如权利要求20所述的磁盘驱动器,其中所述起转控制器的所述状态包括施加到所述主轴电机的加速控制信号。
22.如权利要求21所述的磁盘驱动器,其中所述控制电路可操作以根据以下公式初始化所述积分器:
Accel-Kp·SpeedErr
其中:
Accel表示所述加速控制信号;
Kp表示所述定速控制器的增益;以及
SpeedErr表示所述主轴电机的测量的转速和目标转速之间的差值。
23.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动所述磁盘的主轴电机,其中所述主轴电机在所述主轴电机的单次运转中按照多个电周期操作,并且每个电周期跨越一周期段,所述方法包括:
测量多个所述周期段;
合并至少两个所述周期段;以及
基于所合并的周期段测量所述主轴电机的转速。
24.如权利要求23所述的方法,其中所述主轴电机在单次运转中按照N个电周期操作,并且所述方法进一步包括通过对N个连续周期段求和以产生所述合并的周期段。
25.如权利要求23所述的方法,其中所述方法进一步包括:
随着每个新的周期段被测量,通过对运行的N个连续周期段求和以更新所述合并的周期段;以及
基于所述更新后的合并的周期段更新所述测量的转速。
26.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动所述磁盘的主轴电机,所述方法包括:
测量所述主轴电机的转速;
产生作为所测量的转速的函数的增益,其中所述函数包括次数大于1的多项式;以及
基于所述增益起转所述主轴电机。
27.如权利要求26所述的方法,其中所述增益包括可操作以放大反馈误差信号的反馈增益。
28.如权利要求27所述的方法,其中所述反馈误差信号表示所述测量的转速和目标转速之间的差值。
29.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动所述磁盘的主轴电机,所述方法包括:
测量所述主轴电机的转速;
基于所测量的转速产生前馈控制;以及
基于所述前馈控制起转所述主轴电机。
30.如权利要求29所述的方法,进一步包括基于所述测量的转速和所述磁盘驱动器的环境温度而产生所述前馈控制。
31.如权利要求29所述的方法,进一步包括产生与所述测量的转速成比例的所述前馈控制。
32.如权利要求31所述的方法,其中所述前馈控制补偿所述主轴电机的反电动势。
33.如权利要求29所述的方法,其中所述前馈控制补偿所述主轴电机的阻力矩。
34.如权利要求33所述的方法,进一步包括基于所述测量的转速和所述磁盘驱动器的环境温度而产生所述前馈控制。
35.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动所述磁盘的主轴电机,所述方法包括:
测量所述主轴电机的转速;
基于所测量的转速和速度命令简档而产生控制信号;以及
基于所述控制信号起转所述主轴电机,其中所述速度命令简档保证最坏情形的环境条件下的最小起转时间和有限的功耗。
36.如权利要求35所述的方法,其中所述环境条件包括所述磁盘驱动器的环境温度。
37.如权利要求35所述的方法,其中所述速度命令简档说明所述主轴电机的最大电流消耗。
38.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被致动的磁头和可操作以转动所述磁盘的主轴电机,所述方法包括:
测量所述主轴电机的转速;
基于所测量的转速和目标转速之间的差值产生控制信号;以及
在起转时间的第二部分上基于所产生的所述控制信号起转所述主轴电机;
其中:
基于速度命令简档和所述起转时间的所述第二部分而产生所述目标转速;并且
所述方法进一步包括在产生所述控制信号之前,基于所述主轴电机的初始测量的转速确定所述起转时间的所述第二部分。
39.如权利要求38所述的方法,进一步包括初始化所述起转时间的所述第二部分从而使得初始目标转速大于所述初始测量的转速。
40.如权利要求39所述的方法,其中,当所述控制信号产生时,所述初始目标转速保证所述主轴电机从所述初始测量的转速继续加速。
41.如权利要求40所述的方法,进一步包括:
针对所述起转时间的第一部分,独立于所述控制信号,开始控制所述主轴电机;以及
在所述起转时间的所述第一部分之后,针对所述起转时间的所述第二部分,基于所述控制信号控制所述主轴电机。
42.一种操作磁盘驱动器的方法,所述磁盘驱动器包括在磁盘上方被 致动的磁头和可操作以转动所述磁盘的主轴电机,所述方法包括:
使用起转控制器将所述主轴电机起转到目标转速;
在起转所述主轴电机之后,基于所述起转控制器的状态初始化积分器;以及
使用包括所述积分器的定速控制器控制所述主轴电机。
43.如权利要求42所述的方法,其中所述起转控制器的所述状态包括施加到所述主轴电机的加速控制信号。
44.如权利要求43所述的方法,进一步包括根据以下公式初始化所述积分器:
Accel-Kp·SpeedErr
其中:
Accel表示所述加速控制信号;
Kp表示所述定速控制器的增益;并且
SpeedErr表示所述主轴电机的测量的转速和目标转速之间的差值。
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2013
- 2013-04-24 US US13/869,885 patent/US20140320998A1/en not_active Abandoned
-
2014
- 2014-04-24 CN CN201410245490.1A patent/CN104123951A/zh active Pending
- 2014-09-08 US US14/480,566 patent/US9147428B1/en active Active
-
2015
- 2015-03-13 HK HK15102564.5A patent/HK1202182A1/zh unknown
- 2015-09-03 US US14/844,915 patent/US20150380045A1/en not_active Abandoned
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CN1271934A (zh) * | 1999-04-27 | 2000-11-01 | 国际商业机器公司 | 为磁盘驱动器中的磁头提供主轴电动机控制的方法和系统 |
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Also Published As
Publication number | Publication date |
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HK1202182A1 (zh) | 2015-09-18 |
US20150380045A1 (en) | 2015-12-31 |
US20140320998A1 (en) | 2014-10-30 |
US9147428B1 (en) | 2015-09-29 |
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