{"id":112,"date":"2010-01-22T22:58:06","date_gmt":"2010-01-23T03:58:06","guid":{"rendered":"http:\/\/ammonsengineering.com\/blog\/2010\/01\/current-spikes-smaller\/"},"modified":"2010-01-26T12:09:47","modified_gmt":"2010-01-26T17:09:47","slug":"current-spikes-smaller","status":"publish","type":"post","link":"https:\/\/ammonsengineering.com\/blog\/2010\/01\/current-spikes-smaller\/","title":{"rendered":"Current spikes smaller"},"content":{"rendered":"<p>I removed the capacitors from the motor and repeated the test.\u00a0 The current waveform looks better, but it still has spikes.\u00a0 They are much smaller, but they still make it impossible to measure the current at low duty cycles.<\/p>\n<div id=\"attachment_111\" style=\"width: 577px\" class=\"wp-caption alignnone\"><a href=\"http:\/\/ammonsengineering.com\/blog\/wp-content\/uploads\/2010\/01\/Current-waveform-25-percent-duty-cycle-no-caps.png\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-111\" class=\"size-full wp-image-111 \" title=\"Current waveform, 25% duty cycle, no capacitors\" src=\"http:\/\/ammonsengineering.com\/blog\/wp-content\/uploads\/2010\/01\/Current-waveform-25-percent-duty-cycle-no-caps.png\" alt=\"Current waveform, 25 percent duty cycle, no capacitors\" width=\"567\" height=\"308\" srcset=\"https:\/\/ammonsengineering.com\/blog\/wp-content\/uploads\/2010\/01\/Current-waveform-25-percent-duty-cycle-no-caps.png 945w, https:\/\/ammonsengineering.com\/blog\/wp-content\/uploads\/2010\/01\/Current-waveform-25-percent-duty-cycle-no-caps-150x81.png 150w, https:\/\/ammonsengineering.com\/blog\/wp-content\/uploads\/2010\/01\/Current-waveform-25-percent-duty-cycle-no-caps-300x163.png 300w\" sizes=\"auto, (max-width: 567px) 100vw, 567px\" \/><\/a><p id=\"caption-attachment-111\" class=\"wp-caption-text\">Current waveform, 25% duty cycle, no capacitors<\/p><\/div>\n<p>The oscillations are much more visible, even though they are the same magnitude as before.\u00a0 I noticed that the frequency of the oscillations is proportional to the speed of the motor.\u00a0 They don&#8217;t worry me too much at this point.<\/p>\n<p>My big unknown at the moment is how to measure the average current accurately.\u00a0 My whole control strategy is based on adjusting the duty cycle to control the motor current.\u00a0 If I can&#8217;t measure the current, I&#8217;m not sure how I will control the motor.\u00a0 My only thought at the moment is to perhaps add an inductor to the motor circuit to increase the inductance and smooth out the current waveform.\u00a0 I have no idea if that would actually work, though.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I removed the capacitors from the motor and repeated the test.\u00a0 The current waveform looks better, but it still has spikes.\u00a0 They are much smaller, but they still make it impossible to measure the current at low duty cycles. The oscillations are much more visible, even though they are the same magnitude as before.\u00a0 I [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-112","post","type-post","status-publish","format-standard","hentry","category-software"],"_links":{"self":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/112","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/comments?post=112"}],"version-history":[{"count":3,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/112\/revisions"}],"predecessor-version":[{"id":127,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/posts\/112\/revisions\/127"}],"wp:attachment":[{"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/media?parent=112"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/categories?post=112"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ammonsengineering.com\/blog\/wp-json\/wp\/v2\/tags?post=112"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}