通过并联电阻改变接收线圈的增益-开发者社区

利用电位器调整正交线圈增益

增加0.1nF电筒改进测量效果
测量逐飞制作的正交工字型电感
调试逐飞双通道导航模块

01平衡两个线圈增益

一、线圈增益

前几天测试了正交工字型电感在电磁导航中的特性。由于器件参数的误差，往往会使得实际测量两路信号幅度不同。不同的信号增益，将会影响测量角度的数值。下面，对于两路LC回路，通过并联电阻来调整它们各自的增益，最终使得两个LC谐振回路输出的信号幅度达到平衡。只使用一个 200k欧姆的电位器便可以进行调整，这在实际模块制作和调试中也非常方便。下面通过实验测试一下这种调整方式的效果。

二、实验数据

使用双通道信号采集板测量传感器的信号强度。信号放大倍数是固定的。使用QR10 可编程电阻箱测量不同的并联电阻对于采集信号的影响。下面记录并联电阻从 1kΩ 变化到 1MΩ过程中测量所得到的信号幅值。

测量结果应该是一个随着并联电阻增加，数据单调上升的过程，但实际上中间出现了跳跃和反复。测量 200k欧姆范围内，依然出现了一个跳跃。测量 100k欧姆范围内，依然如此。这个跳跃发生在 83k欧姆的地方。重新采集依然如此。这里猜测应该是 QR10出现的问题。具体什么问题，待会儿通过万用表测量矫正一下。

▲ 图1.2.1 测量从 1k欧姆到1M欧姆对应的测量数值
▲ 图1.2.2 测量从 1k欧姆到200k欧姆对应的测量数值

使用数字万用表测量 QR10的电阻，可以看到实际电阻与设置的电阻之间是相同的，这说明QR10没有问题。重新测量它并联在传感器上，仍然出现上面的跳跃部分。对此只能解释，这是因为QR10内部的线路，引入了除电阻之外的电抗部分，因此改变了 LC 谐振回路的谐振频率，从而影响到实际的信号幅度。

▲ 图1.2.3 测量QR10电阻与测量的电阻

三、增加电阻

利用舵机带动传感器旋转，测量两路信号的幅度。现在在两个 LC 回路并联一个 100k 欧姆的可变电阻。可变电阻现在滑动端处在中间，两个 LC 回路并联大约 50k欧姆左右。

第一次测量，可以看到两路信号幅度不太相同。第一路的幅度比其第二路大了 20% 左右。两路增益不同，不影响角度在0点的数值。但是对于大角度会产生比较大的影响。在角度为 45°时，调整电位器，使得两路线圈数值达到一致。看来这一次调整的有点过了。再反向调整一下，现在还没有平衡。再调整一次，这次看来又不够了。最后再调整一次，现在两路信号的幅值基本平衡了。可以看到计算出来的角度在 180度范围内基本上是线性关系。

※总结 ※

本文测试了利用一个电位器来调整正交电感增益平衡。建议使用一个200k欧姆的电位器，并联在两个线圈信号输出端口以及 2.5V的公共端口。对于 LC 并联电阻如果减小，进而减小该 LC 回路的增益。所以依靠电位器左右调整，可以最终使得两路 LC 接收回路的增益达到一致。使得测量出来的角度在整个范围内都是线性关系。

#!/usr/local/bin/python# -*- coding: gbk -*-#============================================================# TEST3.PY -- by Dr. ZhuoQing 2026-01-14## Note:#============================================================fromheadmimport*fromtsmodule.tsvisaimport*fromtsmodule.tsstm32import*importserialfrom_astimportOrfromserial.serialutilimportSerialException#------------------------------------------------------------''' qr10 = serial.Serial() qr10.baudrate = 115200 qr10.timeout = 0.05 try: qr10.port = 'COM10' except: printf('Set qr10 port COM10 error. ') try: qr10.open() except serial.serialutil.SerialException: printf('Open qr10 port COM10 error.') else: printf('Open qr10 port COM10 Ok.') '''#------------------------------------------------------------UDP_HOST='192.168.0.183'UDP_PORT=8899UDP_BUFSIZE=0x1000sv=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)sv.setsockopt(socket.SOL_SOCKET,socket.SO_SNDBUF,UDP_BUFSIZE)sv.settimeout(0.2)defsvsend(data):ADDR=(UDP_HOST,UDP_PORT)iftype(data)!=str:data=str(data)data=bytes(data,'gbk')sv.sendto(data,ADDR)defsvrecv():try:data,ADDR=sv.recvfrom(UDP_BUFSIZE)exceptsocket.timeout:printf('Meter time out.')data=''iflen(data)>0:returndata.decode('utf-8')else:return''defsvval():svsend('MEMOS')splitstr=svrecv().split(' ')data=[]forvalinsplitstr:iflen(val)>0:data.append(eval(val))returndata#------------------------------------------------------------defgetangle():ispclearreceive()ispsend()ispcopyreceive()tspfocuswindow("TEASOFT:3")time.sleep(.1)for_inrange(10):try:s=clipboard.paste().split("\r\n")ss=s[3].split(" ")returnfloat(ss[0]),float(ss[1]),float(ss[2]),float(ss[3])except:pass#------------------------------------------------------------ddim=linspace(0.5,2.5,100)ispsend('angle')svsend('st f %f\r'%ddim[0])time.sleep(1)c1dim=[]c2dim=[]adim=[]#------------------------------------------------------------forid,dinenumerate(ddim):svsend('st f %f\r'%d)time.sleep(.1)svsend('st f %f\r'%d)time.sleep(.2)a,c1,c2,g=getangle()c1dim.append(c1/g)c2dim.append(c2/g)adim.append(a)printff(d,a,c1,c2,g)tspsave("measure4",ddim=ddim,adim=adim,c1dim=c1dim,c2dim=c2dim)#------------------------------------------------------------svsend('st f %f\r'%ddim[0])time.sleep(1)printf("\a")plt.plot(ddim,c1dim,lw=3,label='CH1')plt.plot(ddim,c2dim,lw=3,label='CH2')plt.plot(ddim,adim,lw=3,label='Angle')plt.xlabel("Dudy",color="steelblue",fontsize=24)plt.ylabel("Measure",color="steelblue",fontsize=24)plt.grid(True,which='both',linestyle='--',alpha=0.7)plt.legend(loc="upper right",fontsize=24)plt.tight_layout()plt.show()#------------------------------------------------------------''' rdim = linspace(1e3, 1e5, 100) vdim = [] adim = [] c1dim = [] c2dim = [] gdim = [] for r in rdim: qr10.write(b'AT+USER.SP=%5.1f\n'%r) time.sleep(.1) a,c1,c2,g = getangle() adim.append(a) c1dim.append(c1) c2dim.append(c2) gdim.append(g) printff(r, a,c1,c2,g) v = c2/g vdim.append(v) tspsave("RMeasure", rdim=rdim, vdim=vdim, adim=adim, c1dim=c1dim, c2dim=c2dim, gdim=gdim) plt.plot(rdim, vdim, lw=3) plt.xlabel("R(omega)", color="steelblue", fontsize=24) plt.ylabel("Data", color="steelblue", fontsize=24) plt.grid(True, which='both', linestyle='--', alpha=0.7) plt.tight_layout() plt.show() '''#------------------------------------------------------------if__name__=="__main__":#--------------------------------------------------------''' r = 10e5 qr10.write(b'AT+USER.SP=%5.1f\n'%r) time.sleep(.1) a,c1,c2,g = getangle() printff(a,c1,c2,g) '''#--------------------------------------------------------#------------------------------------------------------------# END OF FILE : TEST3.PY#============================================================

#!/usr/local/bin/python# -*- coding: gbk -*-#============================================================# TEST5.PY -- by Dr. ZhuoQing 2026-01-14## Note:#============================================================fromheadmimport*fromtsmodule.tsvisaimport*fromtsmodule.tsstm32import*importserialfrom_astimportOrfromserial.serialutilimportSerialException#------------------------------------------------------------qr10=serial.Serial()qr10.baudrate=115200qr10.timeout=0.05try:qr10.port='COM10'except:printf('Set qr10 port COM10 error. ')try:qr10.open()exceptserial.serialutil.SerialException:printf('Open qr10 port COM10 error.')else:printf('Open qr10 port COM10 Ok.')#------------------------------------------------------------rdim=linspace(1e3,1e5,100)mdim=[]dm3068open()forrinrdim:qr10.write(b'AT+USER.SP=%5.1f\n'%r)time.sleep(.5)rr=dm3068res()printff(r,rr)mdim.append(rr)tspsave("QR10",rdim=rdim,mdim=mdim)plt.plot(rdim,mdim,lw=3)plt.xlabel("R(omega)",color="steelblue",fontsize=24)plt.ylabel("RM(omega)",color="steelblue",fontsize=24)plt.grid(True,which='both',linestyle='--',alpha=0.7)plt.tight_layout()plt.show()#------------------------------------------------------------# END OF FILE : TEST5.PY#============================================================

ddim=[0.5000,0.5202,0.5404,0.5606,0.5808,0.6010,0.6212,0.6414,0.6616,0.6818,0.7020,0.7222,0.7424,0.7626,0.7828,0.8030,0.8232,0.8434,0.8636,0.8838,0.9040,0.9242,0.9444,0.9646,0.9848,1.0051,1.0253,1.0455,1.0657,1.0859,1.1061,1.1263,1.1465,1.1667,1.1869,1.2071,1.2273,1.2475,1.2677,1.2879,1.3081,1.3283,1.3485,1.3687,1.3889,1.4091,1.4293,1.4495,1.4697,1.4899,1.5101,1.5303,1.5505,1.5707,1.5909,1.6111,1.6313,1.6515,1.6717,1.6919,1.7121,1.7323,1.7525,1.7727,1.7929,1.8131,1.8333,1.8535,1.8737,1.8939,1.9141,1.9343,1.9545,1.9747,1.9949,2.0152,2.0354,2.0556,2.0758,2.0960,2.1162,2.1364,2.1566,2.1768,2.1970,2.2172,2.2374,2.2576,2.2778,2.2980,2.3182,2.3384,2.3586,2.3788,2.3990,2.4192,2.4394,2.4596,2.4798,2.5000]adim=[0.2169,0.1931,0.1356,0.0946,0.0412,0.0127,-0.0488,-0.1081,-0.1551,-0.1992,-0.2429,-0.2943,-0.3512,-0.3931,-0.4354,-0.4895,-0.5411,-0.5879,-0.6338,-0.6766,-0.7278,-0.7697,-0.8185,-0.8660,-0.9098,-0.9599,-1.0021,-1.0521,-1.0992,-1.1440,-1.1962,-1.2380,-1.2754,-1.3215,-1.3733,-1.4284,-1.4671,-1.5206,-1.5549,1.5334,1.4849,1.4464,1.3968,1.3379,1.3028,1.2510,1.2153,1.1696,1.1064,1.0692,1.0194,0.9693,0.9195,0.8754,0.8309,0.7822,0.7362,0.6852,0.6328,0.5957,0.5497,0.5064,0.4456,0.4032,0.3559,0.3006,0.2541,0.2011,0.1537,0.0966,0.0539,-0.0033,-0.0473,-0.0938,-0.1418,-0.1944,-0.2456,-0.2897,-0.3387,-0.3815,-0.4317,-0.4809,-0.5248,-0.5705,-0.6183,-0.6649,-0.7089,-0.7494,-0.7936,-0.8524,-0.8889,-0.9446,-0.9889,-1.0309,-1.0665,-1.1237,-1.1678,-1.2107,-1.2508,-1.2998]c1dim=[1.4889,1.3235,0.9330,0.6514,0.2849,0.0877,0.3375,0.7478,1.0698,1.3749,1.6702,2.0217,2.3921,2.6719,2.9290,3.2842,3.6043,3.8786,4.1476,4.4356,4.6963,4.9208,5.1605,5.3952,5.5775,5.7711,5.9406,6.1227,6.2763,6.4100,6.5582,6.6500,6.7517,6.8292,6.9027,6.9477,7.0002,7.0172,7.0317,7.0104,6.9785,6.9549,6.8831,6.8033,6.7385,6.6132,6.5345,6.4163,6.2254,6.1057,5.9292,5.7527,5.5243,5.3480,5.1565,4.9091,4.6721,4.3981,4.1111,3.8981,3.6138,3.3647,2.9882,2.7164,2.4190,2.0512,1.7425,1.3844,1.0631,0.6710,0.3747,0.0233,0.3294,0.6526,0.9866,1.3473,1.7031,1.9991,2.3350,2.6206,2.9352,3.2546,3.5251,3.8075,4.0907,4.3853,4.6440,4.8416,5.0837,5.3698,5.5164,5.7625,5.9396,6.1019,6.2004,6.4379,6.5587,6.6734,6.7563,6.8422]c2dim=[6.7577,6.7671,6.8364,6.8648,6.9064,6.9247,6.9119,6.8909,6.8422,6.8089,6.7404,6.6701,6.5290,6.4427,6.2965,6.1649,5.9984,5.8194,5.6430,5.5235,5.2705,5.0775,4.8297,4.5890,4.3376,4.0412,3.7967,3.4949,3.2009,2.9150,2.5785,2.2988,2.0542,1.7387,1.3815,0.9963,0.7283,0.3524,0.1117,0.2623,0.6008,0.8696,1.2100,1.6139,1.8504,2.1897,2.4259,2.7222,3.1185,3.3480,3.6469,3.9481,4.2112,4.4626,4.7075,4.9402,5.1555,5.3808,5.6055,5.7507,5.8979,6.0664,6.2565,6.3686,6.5084,6.6162,6.7078,6.7912,6.8635,6.9237,6.9430,6.9615,6.9555,6.9387,6.9132,6.8434,6.7936,6.7077,6.6282,6.5332,6.3716,6.2384,6.0891,5.9333,5.7503,5.5931,5.4149,5.2033,5.0012,4.6942,4.4782,4.1682,3.9076,3.6566,3.4223,3.0867,2.7961,2.5128,2.2387,1.9012]