>Windows Update で何か問題が起きることで正常に起動しなくなったり再起動を繰り返すなど意図しない動作は起きる場合もあるので、今回も Windows Update が原因で電源が落ちた可能性もありそうですが、明確な原因など判断は難しいですね。。
ReportingEvents.logから事象がWindowsUpdateに起因するか判断できそうでしょうか。再起動(18時頃)前後のログを添付させていただきます。
{84A8C180-1B44-4DBF-91BE-2C913851D0A4} 2019-06-12 15:22:19:416+0900
1 181 [AGENT_INSTALLING_STARTED]
101 {08FF9A94-431D-484F-857F-E9F5326F5F44}
1 0
Acquisition;DSIC Success
Content Install Installation Started: Windows has started installing the following update: 9NCGJX5QLP9M-AppUp.IntelMediaSDKDFP
ftbu832pPk2MQzOR.0.105.1.0.0.2.0
{DFAA747E-F4E2-4056-88C5-63A39436FB18} 2019-06-12 15:22:19:525+0900
1 182 [AGENT_INSTALLING_FAILED]
101 {08FF9A94-431D-484F-857F-E9F5326F5F44}
1 80070057
Acquisition;DSIC Failure
Content Install Installation Failure: Windows failed to install the following update with error 0x80070057: 9NCGJX5QLP9M-AppUp.IntelMediaSDKDFP.
ftbu832pPk2MQzOR.0.105.1.0.0.5.0
{BABC9D26-02C7-404A-9EFD-E694E98BC613} 2019-06-12 15:22:28:990+0900
1 147 [AGENT_DETECTION_FINISHED]
101 {00000000-0000-0000-0000-000000000000}
0 0
Update;ScanForUpdatesForUser Success
Software Synchronization Windows Update Client successfully detected 5 updates.
UsdZKCMXbkWmgzbP.0.3.1.1.0.0.4.0
{2E88679A-5714-44E2-B255-F7F2E55209BA} 2019-06-12 15:22:29:960+0900
1 167 [AGENT_DOWNLOAD_STARTED]
101 {89983B06-E7A0-4685-9A49-C5D7DA646DD1}
1 0
Update;ScanForUpdatesForUser Success
Content Download Download started.
UsdZKCMXbkWmgzbP.0.3.5.2.1.0.0.3.0
{164AC2A3-1A1A-49F2-9C68-04C838690C57} 2019-06-12 15:22:30:549+0900
1 167 [AGENT_DOWNLOAD_STARTED]
101 {3EAADC5B-86E5-4955-9653-D0414A20E188}
1 0
Update;ScanForUpdatesForUser Success
Content Download Download started.
UsdZKCMXbkWmgzbP.0.3.4.2.1.0.0.3.0
{F4370EB0-4D2A-4C27-B0D9-3AC10C2258AC} 2019-06-12 15:22:47:188+0900
1 162 [AGENT_DOWNLOAD_SUCCEEDED]
101 {89983B06-E7A0-4685-9A49-C5D7DA646DD1}
1 0
Update;ScanForUpdatesForUser Success
Content Download Download succeeded.
UsdZKCMXbkWmgzbP.0.3.5.2.1.0.0.115.0
{573B0C88-DD28-4E5D-8357-75B171E51E51} 2019-06-12 15:22:47:236+0900
1 181 [AGENT_INSTALLING_STARTED]
101 {89983B06-E7A0-4685-9A49-C5D7DA646DD1}
1 0
Update;ScanForUpdatesForUser Success
Content Install Installation Started: Windows has started installing the following update: 9N1W692FV4S1-Microsoft.LanguageExperiencePackja-JP
UsdZKCMXbkWmgzbP.0.3.5.3.1.0.0.2.0
{22917770-6815-4CD0-8117-2E7BFE6E3764} 2019-06-12 15:22:47:738+0900
1 183 [AGENT_INSTALLING_SUCCEEDED]
101 {89983B06-E7A0-4685-9A49-C5D7DA646DD1}
1 0
Update;ScanForUpdatesForUser Success
Content Install Installation Successful: Windows successfully installed the following update: 9N1W692FV4S1-Microsoft.LanguageExperiencePackja-JP
UsdZKCMXbkWmgzbP.0.3.5.3.1.0.0.4.0
{A369A970-2C57-4A56-8A94-19F33F0BA5B0} 2019-06-12 15:22:50:692+0900
1 162 [AGENT_DOWNLOAD_SUCCEEDED]
101 {3EAADC5B-86E5-4955-9653-D0414A20E188}
1 0
Update;ScanForUpdatesForUser Success
Content Download Download succeeded.
UsdZKCMXbkWmgzbP.0.3.4.2.1.0.0.126.0
{B0B0B1D7-8FB4-4BD1-B30C-02647943A97D} 2019-06-12 15:22:50:801+0900
1 181 [AGENT_INSTALLING_STARTED]
101 {3EAADC5B-86E5-4955-9653-D0414A20E188}
1 0
Update;ScanForUpdatesForUser Success
Content Install Installation Started: Windows has started installing the following update: 9WZDNCRFHWD2-Microsoft.MicrosoftSolitaireCollection
UsdZKCMXbkWmgzbP.0.3.4.3.1.0.0.2.0
{F158EC5D-AAC3-4D0F-936D-698BE419BC8A} 2019-06-12 15:22:51:258+0900
1 183 [AGENT_INSTALLING_SUCCEEDED]
101 {3EAADC5B-86E5-4955-9653-D0414A20E188}
1 0
Update;ScanForUpdatesForUser Success
Content Install Installation Successful: Windows successfully installed the following update: 9WZDNCRFHWD2-Microsoft.MicrosoftSolitaireCollection
UsdZKCMXbkWmgzbP.0.3.4.3.1.0.0.4.0
{2F4786DB-52F6-4C9C-8A89-1407145CC8DE} 2019-06-13 11:35:15:651+0900
1 183 [AGENT_INSTALLING_SUCCEEDED]
101 {7001A430-AE0D-4403-8C30-919BFED5DA7A}
1 0
UpdateOrchestrator Success
Content Install Installation Successful: Windows successfully installed the following update: 2019-06 x64 ベース システム用 Windows 10 Version 1809 の累積更新プログラム (KB4503327)
E+ePldKJ60e06KYU.1.5.6.1.4.1.0.0.0.0.0.0.0.0
{99E3D82D-A6B5-4278-8885-1E383F9480BD} 2019-06-13 11:35:15:653+0900
1 183 [AGENT_INSTALLING_SUCCEEDED]
101 {906308CD-F0E3-4CA0-B9B1-15B414AF5241}
200 0
UpdateOrchestrator Success
Content Install Installation Successful: Windows successfully installed the following update: 2019-06 x64 ベース システム用 Windows 10 Version 1809 セキュリティ更新プログラム (Adobe Flash Player 対応) (KB4503308)
E+ePldKJ60e06KYU.1.3.6.1.4.1.0.0.0.0.0.0.0.0
{5FA206CF-674E-48B1-8A8A-3FA1265FF41C} 2019-06-13 11:35:15:655+0900
1 183 [AGENT_INSTALLING_SUCCEEDED]
101 {1F595DBA-012D-4237-8D8F-3D110993B8DC}
208 0
UpdateOrchestrator Success
Content Install Installation Successful: Windows successfully installed the following update: 2019-02 x64 ベース システム用 Windows 10 Version 1809 更新プログラム (KB4465065)
E+ePldKJ60e06KYU.1.1.6.1.4.1.0.0.0.0.0.0.0.0
{288018D1-631E-4E2D-A1E6-2591A3997F3B} 2019-06-13 11:40:20:528+0900
1 181 [AGENT_INSTALLING_STARTED]
101 {08FF9A94-431D-484F-857F-E9F5326F5F44}
1 0
Acquisition;DSIC Success
Content Install Installation Started: Windows has started installing the following update: 9NCGJX5QLP9M-AppUp.IntelMediaSDKDFP
ftbu832pPk2MQzOR.0.108.1.0.0.2.0
{A266690C-24CB-4330-9400-5323210260B4} 2019-06-13 11:40:20:675+0900
1 182 [AGENT_INSTALLING_FAILED]
101 {08FF9A94-431D-484F-857F-E9F5326F5F44}
1 80070057
Acquisition;DSIC Failure
Content Install Installation Failure: Windows failed to install the following update with error 0x80070057: 9NCGJX5QLP9M-AppUp.IntelMediaSDKDFP.
ftbu832pPk2MQzOR.0.108.1.0.0.5.0
{34C1504C-00FE-481A-BBF9-017E118A63CB} 2019-06-13 11:40:30:098+0900
1 147 [AGENT_DETECTION_FINISHED]
101 {00000000-0000-0000-0000-000000000000}
0 0
Update;ScanForUpdates Success
Software Synchronization Windows Update Client successfully detected 5 updates.
jsBklyC0v0GxIEna.0.3.1.1.0.0.4.0
{CB1BD16A-55ED-4D61-89DE-7439F75E612C} 2019-06-13 11:40:35:342+0900
1 147 [AGENT_DETECTION_FINISHED]
101 {00000000-0000-0000-0000-000000000000}
0 0
Update;ScanForUpdates Success
Software Synchronization Windows Update Client successfully detected 5 updates.
jsBklyC0v0GxIEna.0.3.1.1.0.0.5.3.0